From SwoDy1 at goshenarc.org Thu May 4 01:02:54 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 03 May 2006 21:02:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040100 SWODY1 SPC AC 040058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT WED MAY 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM PARTS OF THE SRN PLAINS INTO THE OZARK PLATEAU.... CLOSED LOW WILL BEGIN TO GRADUALLY LIFT AWAY FROM THE NORTHERN MINNESOTA BORDER AREA OVERNIGHT...BUT BELT OF STRONG MID/UPPER FLOW WILL PERSIST IN BASE OF BROADER SCALE TROUGH ALONG THE CENTRAL U.S./CANADIAN BORDER. UPSTREAM...ANOTHER CLOSED LOW APPEARS TO BE EVOLVING ACROSS PARTS OF CALIFORNIA/THE INTERMOUNTAIN WEST...IN A MORE SOUTHERN BRANCH OF WESTERLIES...AS A SIGNIFICANT EMBEDDED JET STREAK DIGS OFF THE CALIFORNIA COAST. AHEAD OF THIS FEATURE...A STRONG SUBTROPICAL STREAM IMPULSE/JET STREAK IS NOSING INTO THE SOUTHWESTERN U.S./MEXICO BORDER AREA. ...SOUTHERN PLAINS INTO THE OZARKS... SURFACE RIDGE CONTINUES TO NOSE THROUGH THE CENTRAL PLAINS BENEATH CONFLUENT BELTS OF WESTERLIES. ASSOCIATED SURFACE FRONT IS NOW ADVANCING THROUGH THE OZARKS/NORTHERN OKLAHOMA AND THE TEXAS/OKLAHOMA PANHANDLE REGION...BUT CONVECTIVE DEVELOPMENT HAS BEEN SPARSE IN COVERAGE...LIMITED TO DISTINCT AREAS OF STRONGER MID/UPPER FORCING. ONE OF THESE AREAS IS CURRENTLY OVER THE MISSOURI OZARKS...WHERE WEAK SOUTHERN BRANCH PERTURBATION...PERHAPS CONVECTIVELY INDUCED... HAS AIDED ANOTHER SMALL CONVECTIVE CLUSTER. AS STRONGER MID/UPPER FORCING CONTINUES EASTWARD ACROSS THE MIDDLE MISSISSIPPI VALLEY...INTO ENVIRONMENT SUBSTANTIALLY MODIFIED BY EARLIER CONVECTION...A GRADUAL WEAKENING TREND IS EXPECTED THROUGH LATE EVENING. PRIMARY CONVECTIVE DEVELOPMENT SEEMS LIKELY TO PROCEED ACROSS PARTS OF WEST CENTRAL/NORTHWEST TEXAS INTO THE RED RIVER VALLEY. ONGOING CONVECTIVE CLUSTER EVOLVING NEAR/SOUTHEAST OF LUBBOCK SEEMS LIKELY TO BE SUPPORTED BY MOIST INFLOW OF 40 KT SOUTHERLY LOW-LEVEL JET DEVELOPING ACROSS WESTERN TEXAS. LARGE-SCALE ASCENT WILL BE ENHANCED BY STRENGTHENING DIVERGENCE ASSOCIATED WITH COUPLED SUBTROPICAL AND POLAR JETS...AND SUBSTANTIAL EXPANSION OF CONVECTIVE CLUSTER IS EXPECTED THROUGH 06Z. MID-LEVEL FLOW IS GENERALLY WEAK...BUT LARGE CAPE WILL REMAIN SUPPORTIVE OF HAIL POTENTIAL...AND RELATIVE HUMIDITIES ARE LOW ENOUGH TO SUPPORT ISOLATED DOWNBURSTS...POSSIBLY THE EVOLUTION OF ONE OR MORE COLD POOLS WITH STRONG GUSTY WINDS. ...TENNESSEE VALLEY... WEAK FLOW REGIME AND STABILIZING LOW-LEVEL ENVIRONMENT SUGGEST ANY FURTHER SEVERE THREAT WITH ONGOING CONVECTIVE CLUSTER WILL BE SHORT LIVED. STORMS SHOULD WEAKEN THIS EVENING AS THEY PROGRESS ACROSS MIDDLE TENNESSEE INTO THE SOUTHERN APPALACHIANS. ..KERR.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 05:58:38 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 01:58:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040556 SWODY1 SPC AC 040554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT THU MAY 04 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EVE FROM THE ARKLATEX EASTWARD INTO THE TENNESSEE VALLEY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EVE ACROSS PARTS OF THE SRN PLAINS.... MODELS INDICATE THAT BROAD TROUGHING WILL PERSIST THROUGH THIS FORECAST PERIOD IN THE NORTHERN BRANCH OF THE POLAR WESTERLIES...AND EXPAND EASTWARD FROM THE UPPER MIDWEST/EAST CENTRAL CANADIAN PROVINCES TOWARD THE CANADIAN MARITIMES/NORTH ATLANTIC COAST. AS THIS OCCURS...IMPULSES ARE PROGGED TO CONSOLIDATE IN UPSTREAM SOUTHERN BRANCH TROUGH ACROSS THE INTERMOUNTAIN WEST. EVENTUALLY...A CLOSED MID-LEVEL CIRCULATION IS EXPECTED TO EVOLVE OVER THE GREAT BASIN...AND TROUGHING TO THE SOUTH OF THIS FEATURE WILL COME INCREASINGLY IN PHASE WITH THE SUBTROPICAL STREAM. DOWNSTREAM OF THE SOUTHERN ROCKIES THROUGH THE SOUTH ATLANTIC COAST STATES...MID/UPPER FLOW REGIME WILL REMAIN WEAK...BETWEEN CONFLUENT BELTS OF POLAR WESTERLIES AND THE SUBTROPICAL STREAM. HOWEVER...WITH THE UPPER PATTERN SUPPORTING SOUTHWARD BUILDING SURFACE RIDGE OUT OF CANADA TO THE LEE OF THE ROCKIES... MOIST...POTENTIALLY UNSTABLE AIR WILL BECOME GENERALLY CONFINED TO THIS REGION. FRONT WILL JUST BE ADVANCING INTO THE LOWER OHIO VALLEY AND LOWER GREAT LAKES REGION AT 12Z...BUT SIGNIFICANT MOISTURE RETURN IN WAKE OF PRIOR FRONTAL PASSAGE TO THE LEE OF THE APPALACHIANS AND ASSORTMENT OF OUTFLOW BOUNDARIES ACROSS THE TENNESSEE VALLEY IS NOT ANTICIPATED. ...ARKLATEX THRU NRN GULF STATES/TENNESSEE VALLEY... CONSIDERABLE UNCERTAINTY EXISTS ACROSS THIS AREA CONCERNING DETAILS OF CONVECTIVE DEVELOPMENT. BUT...FRONTAL ZONE ADVANCING SOUTH OF THE LOWER OHIO VALLEY AND OZARK PLATEAU...AND FRONTAL ZONE/OUTFLOW BOUNDARIES EXTENDING ACROSS THE SOUTHERN APPALACHIANS INTO THE TENNESSEE VALLEY...WILL PROVIDE FOCUS FOR INITIATION OF STORMS. THIS SEEMS LIKELY TO OCCUR AS EARLY AS MID DAY AS HEATING ERODES RELATIVELY WEAK INHIBITION. THOUGH SHEAR/FLOW WILL BE WEAK...MIXED LAYER CAPE OF 1500 TO 2000 J/KG BY PEAK HEATING WILL BE SUFFICIENT FOR A FEW VIGOROUS UPDRAFTS WITH DAMAGING WIND GUSTS AND SOME HAIL. A CONVECTIVELY GENERATED MID-LEVEL CYCLONIC VORTICITY CENTER COULD PROVIDE A FOCUS FOR ANOTHER CLUSTER OF STORMS ACROSS THE ARKLATEX INTO THE NORTH CENTRAL GULF STATES THIS EVENING INTO THE OVERNIGHT HOURS. ...SOUTHERN PLAINS... LARGE CONVECTIVE CLUSTER IS EXPECTED TO WEAKEN EARLY IN THE DAY ACROSS THE RED RIVER VALLEY/NORTHERN TEXAS. OUTFLOW BOUNDARY GENERATED BY THIS FEATURE...AND SURFACE FRONT ADVANCING INTO NORTHERN/NORTHWEST TEXAS...ARE THEN EXPECTED TO PROVIDE FOCUS FOR NEW ACTIVITY. THIS MOST LIKELY WILL NOT OCCUR UNTIL VERY LATE IN THE AFTERNOON OR EVENING...AS STABILIZING INFLUENCE OF EARLY ACTIVITY WANES AND LARGE-SCALE ASCENT INCREASES WITH SUBTROPICAL STREAM IMPULSE/JET STREAK. GIVEN CONTINUING PRESENCE OF MOIST BOUNDARY LAYER AND STEEP MID-LEVEL LAPSE RATES...MIXED LAYER CAPE OF 2000 TO 3000 J/KG IS EXPECTED BY PEAK HEATING. THIS ENVIRONMENT WILL BE SUPPORTIVE OF BOTH INTENSE UPDRAFTS AND DOWNDRAFTS...WITH POTENTIAL FOR LARGE HAIL/DAMAGING WIND GUSTS. MODELS SUGGEST A WEAK TO MODERATE SOUTHERLY LOW-LEVEL JET DEVELOPING INTO THE TEXAS HILL COUNTRY BY THIS EVENING...WHICH COULD PROVIDE SUPPORT FOR ANOTHER LARGE MESOSCALE CONVECTIVE SYSTEM. ...OHIO VALLEY INTO THE LOWER GREAT LAKES... MOISTURE RETURN WILL BE LIMITED AHEAD OF FRONT ADVANCING EAST OF THE LOWER GREAT LAKES. THIS IS EXPECTED TO CONFINE CAPE TO VALUES AT OR BELOW 500 J/KG...BUT FORCING ON TAIL END OF FAIRLY VIGOROUS SHORT WAVE TROUGH IS EXPECTED TO BE SUFFICIENT FOR SCATTERED THUNDERSTORMS THIS AFTERNOON ACROSS PARTS OF NEW YORK/ PENNSYLVANIA. THOUGH UPDRAFTS SHOULD BE WEAK...DEEP MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS IN PRESENCE OF WEAK TO MODERATE MEAN FLOW COULD SUPPORT LOCALLY DAMAGING WIND GUSTS. THOUGH FORCING WILL BE WEAKER...WIDELY SCATTERED STORMS COULD DEVELOP WESTWARD ALONG FRONT INTO PARTS OF THE LOWER OHIO VALLEY BY EARLY EVENING...WHERE THERMODYNAMIC ENVIRONMENT MAY BE MORE FAVORABLE FOR HAIL NEAR SEVERE LIMITS. ...GREAT BASIN... FRONTAL ZONE ACROSS SOUTH CENTRAL UTAH INTO WEST CENTRAL COLORADO IS EXPECTED TO AGAIN BE A FOCUS FOR WIDELY SCATTERED LATE AFTERNOON STORMS. MOISTURE IS LIMITED...BUT VERY STEEP LAPSE RATES BENEATH COLD MID-LEVEL TROUGH WILL PROVIDE AT LEAST SOME POTENTIAL FOR HAIL/WIND GUSTS APPROACHING/BRIEFLY EXCEEDING SEVERE LIMITS. ..KERR/GRAMS.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 12:47:13 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 08:47:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041244 SWODY1 SPC AC 041242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT THU MAY 04 2006 VALID 041300Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF SW AND S CNTRL TX... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SRN/CNTRL AND SW TX... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX AND TN VLY TO THE SRN APLCNS... ...SYNOPSIS... WEAK...SLOWLY PROGRESSIVE SPLIT FLOW PATTERN WILL PREVAIL THIS PERIOD ACROSS THE LWR 48. SEVERE TSTM CHANCES SHOULD REMAIN CONFINED TO THE DIFFLUENT SRN BRANCH THAT WILL EXTEND E/NE INTO THE SRN PLNS...DOWNSTREAM FROM CNTRL/SRN CA CLOSED LOW. AT LWR LEVELS...EXPANSIVE SURFACE RIDGE IN WAKE OF NRN STREAM LOW NOW CROSSING ONTARIO WILL CONTINUE TO PRESS S/SE INTO THE SRN PLNS...THE MID/LWR MS VLYS AND THE ERN GRT LKS. EFFECTIVE COLD FRONT MARKING LEADING EDGE OF RIDGE WILL BE SHUNTED S INTO CNTRL TX/SE OK AND CNTRL AR TODAY BY COMPOSITE OUTFLOW FROM OVERNIGHT MCSS. FARTHER E...EXPECT WEAK WARM FRONT THAT HELPED SPAWN STORMS IN MO/AR AND THE LWR TN MS VLY YESTERDAY WILL REDEVELOP E TOWARD THE SRN APLCNS AND WEAKEN. ...S CNTRL TX INTO SE NM... DISSIPATING NRN/CNTRL TX MCS HAS LEFT A WELL-DEFINED OUTFLOW BOUNDARY THAT EXTENDS FROM THE ERN/SRN HILL COUNTRY W ACROSS THE EDWARDS PLATEAU TO NEAR MAF. THE WRN PART OF THE BOUNDARY MAY EDGE A BIT N TODAY BEFORE BEING INTERCEPTED BY SYNOPTIC COLD FRONT NOSING S FROM NEAR LBB. THE COMBINED BOUNDARIES SHOULD MORE OR LESS STALL ALONG ROUGHLY A WNW/ESE AXIS FROM NEAR MAF TO NEAR SJT ...AND LIKELY WILL SERVE AS A FOCUS FOR NEW STORM DEVELOPMENT LATE TODAY. SATELLITE LOOPS SUGGEST PRESENCE OF AN UPR LEVEL IMPULSE NOW OVER SW NM/NRN SONORA THAT SHOULD REACH W CNTRL AND SW TX BY LATE IN THE DAY. SATELLITE ALSO SUGGESTS THAT HEATING WILL BE STRONG IN WAKE OF MCS DEBRIS FROM THE HILL COUNTRY W INTO THE PERMIAN BASIN/SE NM. QUALITY BOUNDARY LAYER MOISTURE IS ALREADY PRESENT AS FAR W AS DRT/SJT...AND SOME WWD ADVECTION OF MOISTURE LIKELY WILL OCCUR INVOF STALLING FRONT/OUTFLOW BOUNDARY THROUGH THE DAY. THUS... EXPECT THAT STRONG INSTABILITY WILL DEVELOP...WITH MLCAPE OF 2000 TO 3000 J/KG LIKELY BY PEAK HEATING. COMBINATION OF STRONG INSTABILITY...WEAK BUT INCREASING LARGE SCALE ASCENT...AND 30+ KT WSWLY MID LEVEL FLOW SHOULD SUPPORT SUPERCELLS WITH BOTH VERY LARGE HAIL AND HIGH WIND. IN ADDITION...ASSUMING THAT THE SURFACE BOUNDARIES DO INDEED BECOME NEARLY STATIONARY...POTENTIAL WILL ALSO EXIST FOR TORNADOES WITH ANY DISCRETE RIGHT-MOVING STORMS THAT MOVE ALONG THE FRONT. GOOD MOISTURE AVAILABILITY...DIURNAL STRENGTHENING OF MODERATE SLY LLJ...AND EWD PROGRESSION OF SAME AS UPR IMPULSE CONTINUES EWD ALL SUGGEST THAT THE TX STORMS WILL EVOLVE INTO A LARGE COMPLEX. THIS SYSTEM SHOULD MOVE E/SE ACROSS S CNTRL AND PERHAPS SE TX THROUGH EARLY FRIDAY. ...ARKLATEX/NRN GULF STATES/TN VLY... MODERATE TO STRONG SURFACE HEATING SHOULD OCCUR FROM THE ARKLATEX E INTO THE PARTS OF MS...AL AND GA TODAY...S AND E OF AFOREMENTIONED MCS OUTFLOW BOUNDARIES. SYNOPTIC SCALE FORCING FOR ASCENT WILL BE WEAK. BUT COMPOSITE RADAR DATA SUGGEST PRESENCE OF SEVERAL MCVS EMBEDDED WITHIN THE ERN OK/N TX CONVECTIVE COMPLEXES THAT LIKELY WILL SERVE TO ENHANCE MESOSCALE ASCENT AS THEY CONTINUE GENERALLY EWD. THIS ENHANCEMENT MAY BE MAXIMIZED FROM CNTRL AR INTO NRN MS/AL...WHERE THE SYSTEMS WILL INTERACT WITH REMNANT WARM FRONT. FOCUSED UPLIFT SHOULD ALSO OCCUR ALONG COLD FRONT SETTLING SE FROM KY INTO TN. MODEST /20-25 KT/ W TO WNWLY MID LEVEL FLOW WILL LIMIT STORM ORGANIZATION AND LONGEVITY. BUT GIVEN EXPECTED DEGREE OF INSTABILITY /SBCAPE OF 1500-2000 J PER KG/ AND FORCING FOR ASCENT PROVIDED BY MCVS...EXPECT INTENSIFICATION OF EXISTING STORMS IN WEAKLY CAPPED ENVIRONMENT BY EARLY AFTERNOON. THIS ACTIVITY COULD YIELD LOCALLY DAMAGING WIND AND MARGINALLY SEVERE HAIL AS STORMS MOVE/DEVELOP E TO THE SRN SLOPES OF THE APLCNS THROUGH THE REMAINDER OF THE DAY. GIVEN LARGELY STATIC PATTERN AND PERSISTENT MOIST INFLOW...THE WIDESPREAD CONVECTION MAY SUPPORT DEVELOPMENT OF AN ADDITIONAL MCV TONIGHT OVER THE LWR TN VLY...WITH AN ATTENDANT THREAT FOR MARGINALLY SEVERE HAIL/WIND AND HEAVY RAIN. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ...GREAT BASIN... COLD FRONT ASSOCIATED WITH CA TROUGH WILL LINGER OVER THE CNTRL GRT BASIN/CNTRL RCKYS TODAY. THE BOUNDARY MAY ONCE AGAIN BE A FOCUS FOR WIDELY SCATTERED LATE AFTERNOON STORMS. MOISTURE WILL BE LIMITED...BUT VERY STEEP LAPSE RATES BENEATH MODERATE SWLY MID LEVEL FLOW ON E SIDE OF TROUGH MAY PROMOTE DEVELOPMENT OF A FEW CELLS WITH HAIL/WIND GUSTS APPROACHING/BRIEFLY EXCEEDING SEVERE LIMITS. ..CORFIDI/GRAMS.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 16:24:20 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 12:24:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041622 SWODY1 SPC AC 041620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES/GUYER.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 17:09:09 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 13:09:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041706 SWODY1 SPC AC 041705 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 1205 PM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... THUNDER GRAPHIC LINES ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 20:01:49 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 16:01:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041959 SWODY1 SPC AC 041958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT THU MAY 04 2006 VALID 042000Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER PARTS OF W-CNTRL AND CNTRL TX... ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN NM TO THE SE TX COAST... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX ACROSS NRN MS... ...ERN NM INTO CNTRL TX... 18Z MESOANALYSIS INDICATES PRESSURE FALLS IN POST-FRONTAL AIR MASS OVER THE TX PNHDL...SUGGESTING THAT FRONT SHOULD DECELERATE THIS AFTERNOON...BECOMING QUASI-STATIONARY FROM SERN NM INTO CNTRL TX. STRONG DAYTIME HEATING COUPLED WITH STEEP LAPSE RATES AND MODEST BOUNDARY-LAYER MOISTURE WILL CONTINUE TO SUPPORT FURTHER DESTABILIZATION INVOF OF THIS BOUNDARY THIS AFTERNOON WITH MLCAPES INCREASING FROM 1000-1500 J/KG OVER SERN NM INTO WRN TX...TO 2000-3000 J/KG INTO CNTRL TX. 18Z MAF SOUNDING INDICATES THAT WIND FIELDS HAVE INCREASED ABOVE 4 KM AGL WITH SUFFICIENT VERTICAL SHEAR /I.E. 30-40 KTS/ PRESENT TO SUPPORT SUPERCELL DEVELOPMENT. VISIBLE SATELLITE AND LATEST RUC GUIDANCE SUGGEST THAT TSTMS WILL DEVELOP BY MID TO LATE AFTERNOON ALONG BOTH: 1) THE IMMEDIATE HIGHER TERRAIN OF CNTRL NM...AND 2) ALONG FRONTAL ZONE ESEWD INTO CNTRL TX WITH STORMS EVENTUALLY MERGING INTO CLUSTERS OR A MCS TONIGHT AND MOVING SEWD THROUGH THE HILL COUNTRY INTO PARTS OF ERN/SERN TX. INITIAL SUPERCELL MODES WILL BE CAPABLE OF LARGE HAIL /SOME SIGNIFICANT/ AND PERHAPS A COUPLE TORNADOES...PRIOR TO EVOLVING INTO MORE OF AN OUTFLOW-DOMINANT CONVECTIVE COMPLEX WITH A THREAT OF HAIL AND HIGH WINDS. ...ARKALTEX INTO NRN MS... WELL-DEFINED MCV CONTINUES TO TRANSLATE EWD THIS AFTERNOON OVER SWRN AR WITH DEQUEEN AR PROFILER INDICATING AN ASSOCIATED NARROW CHANNEL OF 50 KT WLY FLOW AT 6 KM AGL AROUND THE SRN PERIPHERY OF THIS FEATURE. LOW-LEVEL AIR MASS ACROSS NRN LA/SRN AR IS MOIST WITH DEWPOINTS IN THE MID 60S...WHICH ARE CONTRIBUTING TO MODERATE INSTABILITY WITH MLCAPES OF 1000-2000 J/KG. GIVEN THIS MODERATE INSTABILITY AND MESOSCALE ZONE OF MODERATELY STRONG VERTICAL SHEAR...EXPECT THE THREAT OF ORGANIZED SEVERE STORMS INCLUDING SUPERCELLS TO CONTINUE EWD ALONG W-E FRONTAL BOUNDARY INTO THE MS DELTA THIS AFTERNOON INTO TONIGHT. LARGE HAIL AND LOCALLY DAMAGING WINDS APPEAR TO BE THE PRIMARY SEVERE WEATHER THREATS WITH THE MOST INTENSE STORMS. ...SERN TX INTO SRN LA... TSTMS HAVE INTENSIFIED THIS AFTERNOON ACROSS REGION AHEAD OF SECONDARY...WEAKER MCV MOVING MORE SEWD OUT OF THE HILL COUNTRY. AMBIENT AIR MASS REMAINS QUITE MOIST WITH DEWPOINTS OF 65-70 F WHICH ARE LARGELY CONTRIBUTING TO MLCAPES OF 1000-2000 J/KG. MOREOVER...HOUSTON VWP INDICATES RELATIVELY STRONG VEERING WITH HEIGHT WITH 40-45 KTS OF DEEP-LAYER SHEAR. STORMS NEAR CLL HAVE RECENTLY STRENGTHENED...AND GIVEN AMBIENT ENVIRONMENT...FURTHER INTENSIFICATION IS LIKELY THIS AFTERNOON INTO EVENING AS STORMS MOVE SEWD TOWARD THE COAST. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER HAZARDS. ...TN VALLEY SWD INTO NRN PORTIONS OF AL AND GA... REGIONAL RADAR IMAGERY INDICATE TSTMS BECOMING INCREASINGLY NUMEROUS THIS AFTERNOON FROM NEAR CBM EWD ACROSS PARTS OF NRN AL/GA TO NEAR AHN. VISIBLE SATELLITE AND MESOANALYSIS SUGGEST THAT THIS ACTIVITY IS DEVELOPING ALONG AN OUTFLOW BOUNDARY REMNANT FROM EARLIER CONVECTION. WHILE AMBIENT AIR MASS IS MOIST AND MODERATELY UNSTABLE.../MLCAPES OF 1000-1500 J/KG/ AREA VWPS AND RUC OBJECTIVE FIELDS INDICATE THAT VERTICAL SHEAR AND MID-LEVEL LAPSE RATES REMAIN QUITE MARGINAL FOR ORGANIZED...SEVERE STORMS. THUS...CATEGORICAL SLIGHT RISK HAS BEEN REMOVED. NONETHELESS...POTENTIAL WILL EXIST FOR ISOLATED WIND OR HAIL WITH THE MOST INTENSE STORMS INTO THIS EVENING. ...UPPER OH VALLEY INTO WRN/CNTRL PA AND NY... DIABATIC HEATING ALONG WITH SOME INCREASE IN LOW-LEVEL MOISTURE FROM THE SW HAVE RESULTED IN WEAK AIR MASS DESTABILIZATION AHEAD OF SURFACE FRONT THIS AFTERNOON. THUS FAR...MOST INTENSE DEEP CONVECTION HAS REMAINED N OF INTERNATIONAL BORDER OVER FAR SERN ONTARIO IN ASSOCIATION WITH SRN FRINGE OF STRONGER HEIGHT FALLS AHEAD OF UPPER LOW OVER ERN ONTARIO. THIS ACTIVITY MAY MOVE INTO PARTS OF NRN NY LATE THIS AFTERNOON OR EARLY THIS EVENING WITH ADDITIONAL STORM DEVELOPMENT POSSIBLE ALONG COLD FRONT INTO ERN OH OR WRN PA. STEEP LOW-LEVEL LAPSE RATES AND MODEST UNIDIRECTIONAL VERTICAL SHEAR MAY SUPPORT A COUPLE STRONG STORMS CAPABLE OF LOCALLY STRONG WIND GUSTS AND SOME HAIL. ...INTERMOUNTAIN W... STEEP LOW TO MID-LEVEL LAPSE RATES HAVE CONTRIBUTED TO A WEAKLY UNSTABLE ENVIRONMENT THIS AFTERNOON AHEAD OF MID-LEVEL TROUGH SLOWLY TRANSLATING EWD TOWARD THE LOWER CO VALLEY. THESE STEEP LAPSE RATES COUPLED WITH A WELL-MIXED BOUNDARY-LAYER WILL SUPPORT ISOLATED WIND/HAIL WITH THE MOST INTENSE STORMS. ..MEAD.. 05/04/2006  From swody1 at goshenarc.org Thu May 4 17:09:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 13:09:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041706 SWODY1 SPC AC 041705 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 1205 PM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... THUNDER GRAPHIC LINES ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES.. 05/04/2006  From swody1 at goshenarc.org Fri May 5 00:56:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 20:56:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050054 SWODY1 SPC AC 050052 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0752 PM CDT THU MAY 04 2006 VALID 050100Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS PARTS OF THE SRN PLAINS.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF THE CNTRL GULF STATES.... A COLD INTRUSION TO THE LEE OF THE ROCKIES HAS OCCURRED IN ASSOCIATION WITH A BROAD NORTHERN BRANCH TROUGH NOW SLOWLY SHIFTING THROUGH THE EASTERN CANADIAN PROVINCES...AND PARTS OF THE UPPER MIDWEST INTO THE NORTHEAST STATES. SURFACE RIDGE HAS BECOME CENTERED BENEATH CONFLUENCE OF NORTHERN AND SOUTHERN BRANCHES OF WESTERLIES...ACROSS THE NORTHERN/CENTRAL PLAINS...WITH ASSOCIATED FRONTAL ZONE NOW EXTENDING FROM THE LOWER GREAT LAKES THROUGH THE LOWER OHIO VALLEY INTO THE SOUTH CENTRAL HIGH PLAINS. SEVERAL CONVECTIVE OUTFLOWS HAVE SUPPRESSED DEEPER BOUNDARY LAYER MOISTURE TO THE SOUTH OF THIS FRONTAL ZONE...AND WILL REMAIN THE FOCUS FOR THE PRIMARY CONVECTIVE DEVELOPMENT THROUGH THE REMAINDER OF THIS FORECAST PERIOD. ...SOUTHERN PLAINS... OUTFLOW BOUNDARY...EXTENDING ACROSS THE TEXAS HILL COUNTRY AND TRANSPECOS REGION...AND SURFACE FRONTAL ZONE...ACROSS THE TEXAS SOUTH PLAINS INTO EASTERN NEW MEXICO...ARE PROVIDING THE FOCUS FOR ONGOING SCATTERED VIGOROUS THUNDERSTORM ACTIVITY. LOW-LEVEL FLOW ACROSS THIS REGION IS RATHER WEAK...BUT VEERING PROFILES WITH HEIGHT BENEATH MODERATE WESTERLY MID LEVEL FLOW IS CONTRIBUTING TO SUFFICIENT SHEAR FOR ISOLATED SUPERCELLS IN ENVIRONMENT WITH MIXED LAYER CAPE OF 2000 TO 3000 J/KG. THIS ACTIVITY MAY PERSIST THROUGH 02-03Z...BUT WITH ONSET OF SURFACE COOLING...NOCTURNAL SOUTHERLY LOW-LEVEL JET SEEMS LIKELY TO SUPPORT CONSOLIDATING/EXPANDING CONVECTIVE CLUSTER NEAR/EAST OF SAN ANGELO. AS THIS OCCURS...UNSATURATED LOW/MID-LEVELS WILL ENHANCE EVAPORATIVE COOLING NEAR HEAVY PRECIPITATION CORES...AND A DOWNBURST OR TWO MAY OCCUR WITH POTENTIALLY DAMAGING WINDS ON OUTWARD SURGING GUST FRONTS. ...LOWER MISSISSIPPI VALLEY/GULF STATES... CONVECTIVELY GENERATED UPPER IMPULSE/MID-LEVEL CYCLONIC VORTICITY CENTER IS PROVIDING SUPPORT FOR ONGOING CONVECTIVE CLUSTER NOW SPREADING ACROSS THE LOWER MISSISSIPPI VALLEY. THIS IS EMBEDDED WITHIN GENERALLY WEAK FLOW REGIME BETWEEN CONFLUENT BELTS OF POLAR WESTERLIES TO THE NORTH...AND SUBTROPICAL WESTERLIES TO THE SOUTH. HOWEVER...THERMODYNAMIC PROFILES SEEM SUPPORTIVE OF A CONTINUING RISK FOR MARGINALLY SEVERE HAIL/GUSTY WINDS WITH CONVECTIVE SYSTEM AS IT SPREADS ACROSS NORTHERN/CENTRAL MISSISSIPPI THROUGH 03-04Z. THEREAFTER...CONVECTION IS EXPECTED TO WEAKEN IN MORE STABLE/ STABILIZING ENVIRONMENT. ..KERR.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 05:46:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 01:46:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050544 SWODY1 SPC AC 050542 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1242 AM CDT FRI MAY 05 2006 VALID 051200Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE SRN PLAINS.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SOUTH ATLANTIC COAST STATES.... SHORT WAVE IMPULSE ON NOSE OF SEASONABLY STRONG NORTH CENTRAL/NORTHEAST PACIFIC POLAR JET IS ALREADY APPROACHING THE BRITISH COLUMBIA/PACIFIC NORTHWEST COAST. MOST VIGOROUS PORTION OF SYSTEM IS PROGGED TO CONTINUE INLAND ACROSS THE CASCADES AND CANADIAN ROCKIES TODAY...WHILE WEAKER SOUTHERN PORTION DIGS IN SOUTHERN STREAM...TOWARD NORTHERN/CENTRAL CALIFORNIA. IN RESPONSE TO THESE DEVELOPMENTS...SIGNIFICANT SOUTHERN BRANCH TROUGH WILL BE FORCED EASTWARD OUT OF THE GREAT BASIN/SOUTHERN PLATEAU. MODELS SUGGEST THAT THIS WILL OCCUR IN A MORE OR LESS PIECE MEAL FASHION...WITH A SERIES OF SMALLER SCALE IMPULSES PROGRESSING EAST OF THE ROCKIES INTO THE SOUTH CENTRAL STATES. FARTHER DOWNSTREAM...TO THE SOUTH/EAST OF AN AMPLIFYING NORTHERN BRANCH TROUGH...A CONVECTIVELY GENERATED/ENHANCED IMPULSE IN THE WEAKER SOUTHERN STREAM IS FORECAST TO LIFT OUT OF THE TENNESSEE VALLEY. SYSTEM IS EXPECTED TO BECOME INCREASINGLY SHEARED AS IT CROSSES THE CENTRAL/SOUTHERN APPALACHIANS BY MID DAY...BEFORE CONTINUING THROUGH MID/SOUTHERN ATLANTIC COASTAL AREAS LATER TODAY/TONIGHT. ...SOUTHERN PLAINS... CONSIDERABLE STRENGTHENING OF MID-LEVEL FLOW /ON THE ORDER OF 40 TO 50 KT/ IS FORECAST IN A CYCLONIC BELT ACROSS THE SOUTHERN ROCKIES/NORTHERN MEXICAN PLATEAU THROUGH MUCH OF TEXAS TODAY. WHILE THIS WILL CONTRIBUTE TO AN INCREASINGLY FAVORABLE KINEMATIC ENVIRONMENT FOR SUPERCELLS AND SEVERE STORMS AS COMPARED TO RECENT DAYS...CONVECTIVE POTENTIAL THIS PERIOD IS MORE UNCERTAIN DUE TO INFLUENCE OF SEVERAL DAYS OF WIDESPREAD CONVECTION. CONSIDERABLE CONVECTION COULD BE ONGOING EARLY IN THE PERIOD ACROSS PARTS OF SOUTHERN AND EASTERN TEXAS...ASSOCIATED WITH REMNANTS OF WEAKENING CONVECTIVE CLUSTER...WITH NEW DEVELOPMENT POSSIBLE ACROSS THE SOUTH PLAINS IN ASSOCIATION WITH LEAD IMPULSE PROGRESSING EAST OF THE SOUTHERN ROCKIES. STEEP LAPSE RATE ENVIRONMENT AND STRONGER SURFACE HEATING MAY ULTIMATELY BE CONFINED TO THE IMMEDIATE VICINITY OF THE RIO GRANDE AND PECOS VALLEYS. VERY MOIST AIR IS IN PLACE ACROSS THE RIO GRANDE VALLEY WITH 70F DEW POINTS AS FAR NORTH AS DEL RIO. ADVECTION OF THIS MOIST TONGUE WESTWARD THROUGH THE PECOS VALLEY SHOULD OCCUR TODAY...AND WILL CONTRIBUTE TO AT LEAST A NARROW CORRIDOR OF MODERATE TO STRONG INSTABILITY...WITH MIXED LAYER CAPE REACHING 2000-3000 J/KG BY PEAK HEATING. AS NEXT UPPER IMPULSE PROGRESSES EAST OF THE SOUTHERN ROCKIES THIS AFTERNOON...INITIATION OF ADDITIONAL INTENSE CONVECTION IS EXPECTED ALONG OUTFLOW/SURFACE FRONT ADVANCING SOUTHWARD TOWARD THE MIDLAND AREA...AND ALONG DRY LINE NEAR THE PECOS RIVER. ISOLATED SUPERCELLS ARE EXPECTED...WITH POTENTIAL FOR VERY LARGE HAIL AND TORNADOES. THIS ACTIVITY IS EXPECTED TO CONTINUE INTO EARLY EVENING...BEFORE EVOLVING UPSCALE INTO A STRONG/SEVERE MESOSCALE CONVECTIVE SYSTEM AS INFLOW STRENGTHENS ASSOCIATED WITH SOUTHEASTERLY LOW-LEVEL JET THROUGH THE RIO GRANDE VALLEY. ...SOUTH ATLANTIC COAST STATES... MOISTENING BOUNDARY LAYER AND STRONG SURFACE HEATING IS EXPECTED TO CONTRIBUTE TO DESTABILIZING ENVIRONMENT TO THE LEE OF THE SOUTHERN APPALACHIANS TODAY. MODELS SUGGEST MIXED LAYER CAPE WILL REACH 1000-2000 J/KG BY PEAK AFTERNOON HEATING. THIS SHOULD BE SUFFICIENT FOR SCATTERED VIGOROUS CONVECTIVE DEVELOPMENT FROM GEORGIA THROUGH THE CAROLINAS...AIDED BY FORCING ASSOCIATED WITH WEAK SOUTHERN BRANCH IMPULSE. BELT OF 20 TO 30 KT WESTERLY MID-LEVEL FLOW MAY ACCOMPANY THIS FEATURE...CONTRIBUTING TO MODERATE STORM MOTIONS...POSSIBLY ENHANCING RISK FOR DAMAGING WINDS IN STRONGER STORMS. HAIL APPROACHING OR EXCEEDING SEVERE LIMITS MAY ALSO OCCUR. ..KERR/GRAMS.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 12:42:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 08:42:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051239 SWODY1 SPC AC 051238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT FRI MAY 05 2006 VALID 051300Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NM TO THE LOWER MS RIVER VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE SOUTHEAST... ...SRN HIGH PLAINS ACROSS MUCH OF TX... SURFACE PATTERN HAS BEEN MUDDLED ACROSS THIS AREA BY EXTENSIVE CONVECTION/MCS ACTIVITY OVER THE PAST FEW NIGHTS. PRIMARY SURFACE COLD FRONT APPEARS TO EXTEND FROM THE ARKLATEX REGION W-SWWD INTO SERN NM AT 12Z...WITH MARINE AIR /70+F DEW POINTS/ REMAINING CONFINED TO DEEP SOUTH TX AND JUST OFF THE MIDDLE AND UPPER TX COAST. WEAK SURFACE LOW NOW EVIDENT OVER FAR SERN NM WILL BECOME BETTER DEFINED ALONG INTERSECTION OF COLD FRONT AND DRY LINE THROUGH THE DAY AHEAD OF PROMINENT MID/UPPER LEVEL TROUGH NOW MOVING ACROSS THE LOWER CO RIVER VALLEY. ASSOCIATED 40-50 KT WLY MID LEVEL JET WILL OVERSPREAD MUCH OF THE SRN HIGH PLAINS THROUGH THE DAY...AS LARGE SCALE PRESSURE FALLS INCREASE SSELY LOW LEVEL FLOW. THIS WILL PROVIDE A VERY FAVORABLE SETUP FOR SUPERCELLS FROM PORTIONS OF CENTRAL/SERN NM ACROSS MUCH OF WRN TX BY THE MID AFTERNOON WITH EFFECTIVE BULK SHEAR IN EXCESS OF 50 KT...DEPENDING UPON QUALITY OF BOUNDARY LAYER AIR MASS. WEDGE OF MID 60F SURFACE DEW POINTS REMAINS IN PLACE FROM THE TX BIG BEND ACROSS THE TRANS PECOS EARLY THIS MORNING. INCREASING SELY SURFACE WINDS AND LARGE SCALE PRESSURE FALLS WILL LIKELY LIFT WARM FRONT/RICHER GULF MOISTURE NWD ALONG AND WEST OF THE HILL COUNTRY THROUGH THE DAY...WITH NARROW WEDGE OF LOW-MID 50F SURFACE DEW POINTS EXTENDING INTO PORTIONS OF CENTRAL NM LATER TODAY. THIS WILL SUPPORT AN AXIS OF MODERATE TO STRONG INSTABILITY FROM SRN/CENTRAL TX NWWD INTO THE SERN NM BY THE MID TO LATE AFTERNOON. INCREASING LARGE SCALE ASCENT AND CONVERGENCE/UPSLOPE WILL BREAK CAP AND INITIATE SEVERE THUNDERSTORMS NEAR HIGHER TERRAIN AND TRIPLE POINT/DRY LINE OVER SERN NM/SWRN TX BY 22Z. SUPERCELLS WILL BE LIKELY WITHIN THIS ZONE WITH ATTENDANT THREATS OF VERY LARGE HAIL AND PERHAPS A FEW TORNADOES. TORNADO THREAT MAY INCREASE INTO THE EARLY EVENING AS ACTIVITY MOVES INTO RICHER BOUNDARY LAYER MOISTURE AND STRONGER LOW LEVEL SHEAR ACROSS THE EDWARDS PLATEAU REGION. EXPECT ACTIVITY WILL INTENSIFY INTO A SEVERE MCS AND POSSIBLY EVOLVE INTO A BOW ECHO WITH INCREASED WIND DAMAGE THREAT AS ACTIVITY SPREADS EWD ALONG INSTABILITY GRADIENT/SURFACE BOUNDARY WITH ATTENDANT SEVERE REACHING THE TX COASTAL PLAIN OVERNIGHT. ...LOWER MS RIVER VALLEY INTO THE CENTRAL GULF COAST... MCV/VORT MAX ASSOCIATED WITH MCS WHICH TRAVERSED NRN TX OVERNIGHT WAS NOW OVER NERN TX. AHEAD OF THIS FEATURE...AXIS OF RICH GULF MOISTURE IS PERSISTING ALONG THE SABINE RIVER/CENTRAL LA WHERE 12Z LCH SOUNDING INDICATES VERY STEEP LAPSE ARE IN PLACE. LOW LEVEL WINDS AND SUBSEQUENT LOW LEVEL SHEAR REMAIN RATHER WEAK. HOWEVER...20-30 KT EFFECTIVE SHEAR SHOULD SUPPORT ORGANIZED MULTICELL CLUSTERS/LINES WITH THREATS OF LARGE HAIL DAMAGING WINDS AS STORMS INCREASE AND DEVELOP SEWD TODAY. EWD EXTENT OF STRONGER STORMS WILL BE LIMITED BY CONVECTIVELY-STABILIZED AIR NOW IN PLACE OVER CENTRAL MS. ...SOUTHEAST... MODELS IN AGREEMENT IN MOVING VORT MAX/SHORTWAVE TROUGH EWD OUT OF AL AND INTO GA/SC TODAY. AHEAD OF THIS FEATURE ABUNDANT HEATING WILL DEVELOP...ESPECIALLY INTO ERN GA/SC...WHERE LOW LEVEL LAPSE RATES BECOME QUITE STEEP. OVERALL MLCAPES WILL REMAIN MARGINAL WITH SURFACE DEW POINTS IN THE LOWER 60S. HOWEVER...MLCAPE WILL BE SUFFICIENT FOR SCATTERED THUNDERSTORMS AS LARGE SCALE ASCENT SPREADS EWD TOWARDS THE CAROLINAS TODAY. GIVEN MODEST WLY FLOW ALOFT AND STEEP LOW LEVEL LAPSE RATES...ISOLATED WIND DAMAGE AND HAIL ARE EXPECTED TO ACCOMPANY STRONGER CORES/LINES INTO THE EARLY EVENING. ..EVANS.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 16:35:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 12:35:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051629 SWODY1 SPC AC 051628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT FRI MAY 05 2006 VALID 051630Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS SW TX.... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK...FROM ERN NM TO SRN LA.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FOR PARTS OF GA/SC/NC.... ...SW/CENTRAL TX AREA THIS AFTERNOON INTO TONIGHT... THE PRIMARY SURFACE BAROCLINIC ZONE EXTENDS FROM ROUGHLY MAF TO ACT AS OF MID MORNING...WITH A SEPARATE CONVECTIVE OUTFLOW BOUNDARY FARTHER S ACROSS THE MIDDLE TX COAST. LOW-MID 60S BOUNDARY LAYER DEWPOINTS ARE SPREADING NWWD ALONG THE RIO GRANDE VALLEY TOWARD SW TX /S OF THE FRONT/...WHILE A PRONOUNCED MID LEVEL TROUGH IS MOVING EWD FROM SRN AZ TO SRN NM. MID-UPPER LEVEL FLOW WILL INCREASE OVER W TX IN ADVANCE OF THIS SYSTEM THROUGH THE AFTERNOON...WHILE CLOUD BREAKS S OF THE FRONT ALLOW SUBSTANTIAL SURFACE HEATING/DESTABILIZATION. MODIFIED 12Z SOUNDINGS...AND SHORT TERM MODEL FORECASTS...SUGGEST THE LIKELIHOOD OF 2000-3000 J/KG MLCAPE ALONG AND S OF THE FRONT THIS AFTERNOON FROM SW INTO CENTRAL TX. ADDITIONALLY...FORECAST HODOGRAPHS APPEAR SUPPORTIVE OF SUPERCELLS WITH EFFECTIVE SRH AND BULK SHEAR OF 150-250 M2/S2 AND AOA 50 KT...RESPECTIVELY. EXPECT SCATTERED SEVERE STORMS TO DEVELOP BY MID-LATE AFTERNOON INVOF THE SURFACE FRONT ALONG AN AXIS FROM CNM-MAF-SJT...WITH CONVECTION INCREASING IN COVERAGE AND SPREADING EWD/ESEWD INTO CENTRAL TX THIS EVENING. THE STRONG VERTICAL SHEAR AND STEEP MID LEVEL LAPSE RATES WILL SUPPORT A THREAT FOR VERY LARGE HAIL WITH THE SUPERCELLS...ALONG WITH A FEW TORNADOES WHERE LOW-LEVEL MOISTURE/SHEAR ARE MAXIMIZED FOR STORMS MOVING ALONG THE SURFACE BOUNDARY. LATER THIS EVENING...CONVECTION MAY GROW UPSCALE INTO ONE OR MORE MCS/S...WITH AN INCREASING THREAT FOR DAMAGING WINDS. ...SRN LA AREA THIS AFTERNOON... THUNDERSTORMS WILL LIKELY INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON ALONG OUTFLOW BOUNDARIES ACROSS S CENTRAL/SE LA. MLCAPE VALUES NEAR 2000 J/KG WILL SUPPORT A THREAT FOR DAMAGING DOWNBURST WINDS AND LARGE HAIL WITH THE MORE INTENSE STORMS THIS AFTERNOON. ...GA/SC AREA THIS AFTERNOON... AN MCV OVER NRN AL WILL MOVE EWD OVER GA/SC THIS AFTERNOON/EVENING AS A COLD FRONT DRIFTS SEWD ACROSS THIS SAME REGION. THOUGH LOW-LEVEL MOISTURE AND MID LEVEL LAPSE RATES APPEAR MARGINAL FOR SEVERE STORMS ACROSS GA/SC...STEEP LOW-LEVEL LAPSE RATES AND A BELT OF 30-40 KT FLOW S OF THE AL MCV MAY SUPPORT A FEW STRONG/DAMAGING GUSTS WITH MULTICELL CLUSTERS THIS AFTERNOON. A MARGINAL SEVERE HAIL THREAT WILL ALSO ACCOMPANY THE STRONGER STORMS. ..THOMPSON/CROSBIE.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 19:49:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 15:49:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051944 SWODY1 SPC AC 051943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT FRI MAY 05 2006 VALID 052000Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER FAR SERN NM SEWD ACROSS THE TX PERMIAN BASIN AND CONCHO VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT FROM ERN NM EWD INTO CNTRL AND SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER ERN GA AND MUCH OF SC... ...ERN NM AND TX... EARLY AFTERNOON MESOANALYSIS INDICATED PRIMARY SURFACE BOUNDARY FROM SERN NM ESEWD INTO CNTRL TX INTO W-CNTRL LA WITH ATTENDANT DRY LINE BECOMING BETTER DEFINED FROM WEAK TRIPLE POINT LOW NEAR CNM SSEWD INTO THE TX BIG BEND REGION. WHILE LOW CLOUDS HAVE PERSISTED N OF THIS BOUNDARY OVER THE TX S PLAINS...COMPARATIVELY STRONGER DIABATIC HEATING COUPLED WITH DEWPOINTS IN THE UPPER 50S/LOWER 60S AND STEEP LAPSE RATES ARE CONTRIBUTING TO MODERATE INSTABILITY /REF. 18Z MAF SOUNDING/ ALONG AND S OF BOUNDARY WITH MLCAPES OF 1000-2000 J/KG. SATELLITE IMAGERY AND REGIONAL RADAR DATA SHOW TSTMS INCREASING IN COVERAGE AND INTENSITY OVER THE HIGHER TERRAIN OF NERN AND E-CNTRL NM AS LEADING EDGE OF STRONGER FORCING ASSOCIATED WITH SRN ROCKIES MID-LEVEL TROUGH HAS OVERSPREAD WRN EXTENSION OF INSTABILITY AXIS. EXPECT THESE TSTMS TO INCREASE IN COVERAGE THIS AFTERNOON INTO EVENING EWD INTO THE TX PNHDL AND S PLAINS AS THIS FORCING FOR ASCENT CONTINUES TO SHIFT EWD. THE MAJORITY OF THESE STORMS WILL LIKELY REMAIN ELEVATED...THOUGH SUPERCELLS CAPABLE OF LARGE HAIL WILL BE POSSIBLE OWING TO THE STEEP MID-LEVEL LAPSE RATES...MODERATE ELEVATED INSTABILITY AND 40-50 KTS OF EFFECTIVE BULK SHEAR. MORE INTENSE SURFACE-BASED STORM DEVELOPMENT IS ANTICIPATED BY MID TO LATE AFTERNOON NEARER TO SURFACE BOUNDARY OVER SERN NM INTO THE PERMIAN BASIN WHERE SUPERCELLS APPEAR LIKELY. WHILE LARGE HAIL /SOME SIGNIFICANT/ WILL BE THE PRIMARY SEVERE WEATHER THREAT...TORNADOES WILL BE POSSIBLE WITH ANY MATURE SUPERCELLS WHICH CAN FAVORABLY INTERACT WITH SYNOPTIC OR ANY SMALLER-SCALE BOUNDARIES WHERE LOW-LEVEL SHEAR WILL BE ENHANCED. ADDITIONAL STORM DEVELOPMENT POSSIBLE THIS AFTERNOON FARTHER DOWNSTREAM ALONG SYNOPTIC FRONT OVER THE CONCHO VALLEY AND ALONG DRY LINE OR OROGRAPHICALLY FAVORED AREAS OF SWRN TX. SAME GENERAL LARGE-SCALE REGIME WILL SUPPORT SUPERCELLS IN THESE AREAS AS WELL. UPSCALE GROWTH OF ANY MORE DISCRETE STORMS OVER WRN OR SWRN TX INTO A MCS WILL LIKELY OCCUR OVERNIGHT WITH A THREAT OF HIGH WINDS AND HAIL SPREADING EWD INTO CNTRL TX. ...SRN LA... CLUSTERS OF STRONG TSTMS ARE IN PROGRESS THIS AFTERNOON OVER SRN LA IN ADVANCE OF WEAK MID-LEVEL IMPULSE SHIFTING SEWD THROUGH CNTRL LA. AMBIENT AIR MASS REMAINS MOIST AND MODERATELY UNSTABLE...WHICH SHOULD SUPPORT A FEW VIGOROUS UPDRAFTS CAPABLE OF MARGINALLY SEVERE WIND AND HAIL. ...ERN GA INTO CNTRL/ERN NC... REGIONAL RADAR IMAGERY INDICATES A BROKEN ARC OF TSTMS FROM NEAR AHN SWD INTO THE ERN FL PNHDL MOVING EWD AT 20-25 KTS. FORCING FOR ASCENT AHEAD OF CONVECTIVELY-INDUCED VORTICITY MAXIMUM OVER NWRN GA COUPLED WITH A MOIST AND MODERATELY UNSTABLE AIR MASS WILL LIKELY MAINTAIN THESE TSTMS EWD ACROSS THE REMAINDER OF GA INTO SC THIS AFTERNOON AND EVENING. WHILE REGIONAL VWPS INDICATE THAT VERTICAL SHEAR REMAINS QUITE WEAK...DATA NEAR MCV SUGGEST SOME LOCAL INCREASE IN MID AND HIGH-LEVEL WIND FIELDS WHICH MAY SUPPORT SOME STORM ORGANIZATION WITH A THREAT OF LOCALLY DAMAGING WINDS AND SOME SEVERE HAIL. ..MEAD.. 05/05/2006  From swody1 at goshenarc.org Sat May 6 01:03:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 21:03:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060100 SWODY1 SPC AC 060058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT FRI MAY 05 2006 VALID 060100Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF W CNTRL TEXAS.... ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS A LARGE PART OF THE SRN PLAINS.... NORTHERN BRANCH TROUGH OVER EASTERN CANADA AND THE NORTHEASTERN U.S. HAS AMPLIFIED IN RESPONSE TO EMBEDDED DIGGING SHORT WAVE IMPULSE...WHICH WILL TURN EASTWARD ACROSS THE GREAT LAKES REGION OVERNIGHT. AS THIS 0CCURS...AND UPSTREAM SHORT WAVE TROUGH PROGRESSES INTO THE PACIFIC COAST ON NOSE OF SEASONABLY STRONG NORTHERN PACIFIC JET...SOUTHERN BRANCH TROUGH CONTINUES TO BREAK DOWN AND SHIFT EASTWARD OUT OF THE INTERMOUNTAIN WEST. ONE SIGNIFICANT SHORT WAVE IMPULSE ASSOCIATED WITH THE LATTER FEATURE IS ALREADY SUPPORTING WIDESPREAD CONVECTIVE DEVELOPMENT ACROSS THE SOUTH CENTRAL HIGH PLAINS. UPSTREAM IMPULSE IS QUICKLY ON ITS HEELS...AND PROGGED EAST OF THE FOUR CORNERS INTO THE SOUTHERN HIGH PLAINS BY 12Z SATURDAY. THIS WILL CONTRIBUTE TO FURTHER CONVECTIVE DEVELOPMENT ACROSS THE SOUTHERN PLAINS OVERNIGHT. ...SOUTHERN PLAINS... WHILE BAROCLINIC ZONE ASSOCIATED WITH THE SOUTHERN STREAM EXTENDS ACROSS UPPER TEXAS COASTAL AREAS THROUGH THE HILL COUNTRY INTO THE RIO GRANDE VALLEY...INHIBITION HAS LIMITED CONVECTIVE DEVELOPMENT ACROSS THIS REGION SO FAR. THE SAME GENERALLY APPLIES FOR THE DRY LINE EAST OF THE BIG BEND INTO SOUTHEAST NEW MEXICO. THE PRIMARY FORCING FOR CONVECTION HAS BEEN CONFINED TO A WARM ADVECTION REGIME ALONG A BAROCLINIC ZONE ASSOCIATED WITH THE NORTHERN STREAM...ACROSS THE TEXAS SOUTH PLAINS. THIS IS JUST NORTH OF WHERE STRONG HEATING OCCURRED EAST OF DRY LINE...CONTRIBUTING TO MIXED LAYER CAPE AROUND 2000 J/KG IMMEDIATELY NEAR SURFACE FRONT...AND MOST UNSTABLE CAPE IN EXCESS OF 2000 IN A NARROW CORRIDOR TO THE NORTH. MULTIPLE SUPERCELLS ARE ONGOING ALONG THE BOUNDARY ACROSS THE SOUTH PLAINS INTO PARTS OF NORTHWEST TEXAS...AND A CONSOLIDATION INTO A LARGER CONVECTIVE CLUSTER APPEARS UNDERWAY NEAR/WEST OF ABILENE. EASTERLY COMPONENT TO LOW-LEVEL FLOW BENEATH 30 TO 50 KT WESTERLY MID-LEVEL FLOW IS CONTRIBUTING TO VERY STRONG SHEAR SUPPORTIVE OF CONTINUING EVOLUTION OF A SEVERE MESOSCALE CONVECTIVE SYSTEM...WITH POTENTIAL FOR STRONG DAMAGING WINDS. HIGHEST WIND DAMAGE POTENTIAL APPEARS POSSIBLE ACROSS THE ABILENE AREA THROUGH 02-03Z...BEFORE THREAT BEGINS TO DIMINISH IN MORE STABLE OR STABILIZING LOW-LEVEL ENVIRONMENT ALONG FRONT FARTHER TO THE EAST...ACROSS AREAS NEAR/SOUTH OF DALLAS. INITIAL CLUSTER MAY DISSIPATE OVERNIGHT...BUT WITH THE APPROACH OF THE NEXT IMPULSE...INCREASING LOW/MID-LEVEL WARM ADVECTION MAY SUPPORT ADDITIONAL STRONG/SEVERE STORMS WITH PRIMARILY LARGE HAIL POTENTIAL NORTH/WEST OF THE SAN ANTONIO/HOUSTON AREAS RESPECTIVELY. ...SOUTH ATLANTIC COAST STATES... CONVECTION HAS BECOME FAIRLY WIDESPREAD FROM GEORGIA THROUGH THE CAROLINAS...SUPPORTED BY WEAK SOUTHERN BRANCH TROUGH. HOWEVER... INTENSITY OF ACTIVITY SHOULD CONTINUE TO DIMINISH AS ENVIRONMENT STABILIZES WITH LOSS OF DAYTIME HEATING. ..KERR.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 05:58:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 01:58:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060556 SWODY1 SPC AC 060554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT SAT MAY 06 2006 VALID 061200Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE SRN PLAINS INTO THE WRN/CNTRL GULF COAST.... STRONG ZONAL NORTH PACIFIC JET CONTINUES TO PROPAGATE TOWARD THE PACIFIC NORTHWEST COAST. ASSOCIATED SHORT WAVE TROUGH ON NOSE OF THIS FEATURE IS SPLITTING IN DISTINCT NORTHERN/SOUTHERN BRANCHES OF STRONGER FLOW EXTENDING INLAND DOWNSTREAM...WITH STRONGER NORTHERN IMPULSE PROGGED EAST OF THE CANADIAN/NORTHERN U.S. ROCKIES BY 12Z SUNDAY. WEAKER SOUTHERN IMPULSE IS FORECAST TO DIG INTO THE LOWER COLORADO VALLEY/NORTHERN BAJA...AND LAST IN SERIES OF SHORT WAVES...ASSOCIATED WITH WHAT IS LEFT OF LARGER SCALE SOUTHERN BRANCH TROUGH...IS PROGGED TO ACCELERATE EAST NORTHEAST OF THE SOUTHERN HIGH PLAINS AND RED RIVER VALLEY. FARTHER EAST...AS MOST SIGNIFICANT SHORT WAVE EMBEDDED WITHIN NORTHERN BRANCH TROUGH LIFTS FROM THE LOWER LAKES THROUGH THE CANADIAN MARITIMES/NORTH ATLANTIC COAST...WEAK TROUGH IN THE SOUTHERN BRANCH WILL FINALLY PROGRESS EAST OF SOUTH ATLANTIC COASTAL AREAS. FORCING ASSOCIATED WITH VARIOUS SHORT WAVE TROUGHS AND SEASONABLE INSTABILITY WILL SUPPORT SCATTERED THUNDERSTORM ACTIVITY ACROSS THE NATION TODAY. HOWEVER...LOW-LEVEL COOLING/DRYING EAST OF THE ROCKIES...PRIMARILY IN ASSOCIATION WITH AMPLIFIED NORTHERN BRANCH TROUGH...BUT ALSO IN PART DUE TO EXTENSIVE CONVECTIVE DEVELOPMENT ASSOCIATED WITH THE SOUTHERN STREAM...HAS NOW SUPPRESSED SIGNIFICANT MOISTURE TO SOUTHERN/EASTERN TEXAS AND THE CENTRAL GULF COAST. ...SOUTHERN PLAINS/LOWER MISSISSIPPI VALLEY... ONE OR MORE CLUSTERS OF STORMS IS EXPECTED TO BE ONGOING AT THE BEGINNING OF THE FORECAST PERIOD ACROSS PARTS OF SOUTHEAST TEXAS/ LOUISIANA. IT SEEMS MOST PROBABLE THAT CONVECTION NEAR/EAST OF CONVECTIVELY INDUCED/ENHANCED CYCLONIC VORTICITY CENTER WILL BE WEAKENING NEAR THE SABINE RIVER. HOWEVER...VIGOROUS STORMS MAY PERSIST IN ASSOCIATION WITH LOW-LEVEL CONVERGENCE/WARM ADVECTION ALONG OUTFLOW BOUNDARY PROGRESSING TOWARD MID/UPPER TEXAS COASTAL AREAS. THIS MAY PROVIDE THE PRIMARY SEVERE THREAT THIS FORECAST PERIOD AS IT PROGRESSES ACROSS HOUSTON AND ADJACENT AREAS BY MID DAY. REDEVELOPMENT IN WAKE OF THIS ACTIVITY IS UNCERTAIN. SIGNIFICANT STABILIZATION OF LOWER LEVELS MAY OCCUR ACROSS A LARGE PORTION OF CENTRAL/EASTERN TEXAS. ADDITIONALLY...MID-LEVEL SUBSIDENCE/WARMING SOUTH OF 50 KT CYCLONIC 500 MB JET PROGGED ACROSS NORTHERN TEXAS DURING THE DAY WILL BE INHIBITIVE. HOWEVER...BOUNDARY LAYER WILL REMAIN MOIST AND POTENTIALLY MODERATELY UNSTABLE NEAR INTERSECTION OF STALLING OUTFLOW BOUNDARY AND DRY LINE...NEAR/NORTH OF SAN ANTONIO BY LATE AFTERNOON. THIS COULD SERVE AS THE FOCUS FOR AT LEAST ISOLATED NEW CONVECTIVE DEVELOPMENT. IF THIS OCCURS...GENERALLY LIGHT BUT VEERING WINDS WITH HEIGHT BENEATH MODERATE WESTERLY MID-LEVEL FLOW WILL BE SUFFICIENT FOR SUPERCELLS...PRIMARILY WITH LARGE HAIL/GUSTY WINDS. OTHER STORMS COULD DEVELOP OFF THE HIGHER TERRAIN OF MEXICO THROUGH THE LOWER RIO GRANDE VALLEY BY EARLY EVENING. THE GFS...MORE SO THAN THE NAM...SUGGESTS THAT FORCING ASSOCIATED WITH THE SOUTHERN STREAM IMPULSE COULD SUPPORT ADDITIONAL SIGNIFICANT CONVECTIVE DEVELOPMENT NEAR LINGERING SYNOPTIC FRONTAL ZONE ACROSS NORTH CENTRAL/NORTHEAST TEXAS LATE THIS AFTERNOON. BOUNDARY LAYER RECOVERY NORTH OF COMPOSITE CONVECTIVE OUTFLOW IS UNCERTAIN...BUT THIS ACTIVITY COULD AT LEAST POSE A RISK FOR LARGE HAIL BEFORE WEAKENING ACROSS THE LOWER MISSISSIPPI VALLEY THIS EVENING. ..KERR/JEWELL.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 12:41:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 08:41:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061238 SWODY1 SPC AC 061237 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0737 AM CDT SAT MAY 06 2006 VALID 061300Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CENTRAL/SRN TX INTO SRN LA... ...UPPER TX COAST ACROSS SRN LA... LINEAR MCS WAS MOVING INTO THE SABINE RIVER VALLEY WITH MAIN IMPETUS BOWING OFF THE SERN TX COAST AT 12Z. THUS...SLOWER MOVING N-S ORIENTED AXIS OF STRONG STORMS WILL SPREAD EWD ACROSS WRN LA THIS MORNING AS WEAK SHORTWAVE TROUGH SHIFTS TOWARD THE LOWER MS RIVER VALLEY. COMPOSITE OUTFLOW BOUNDARY/COASTAL FRONT EXTENDED FROM THE MS RIVER DELTA WWD INTO LINEAR MCS JUST NORTH OF THE UPPER TX COAST EARLY THIS MORNING. A VERY MOIST BOUNDARY LAYER REMAINS SOUTH OF THIS FRONT WHICH WILL LIKELY LIFT SLOWLY NWD AS PRESSURE FALLS AND SLY LOW LEVEL WINDS INCREASE ACROSS SRN LA TODAY. MID LEVEL LAPSE RATES REMAIN QUITE STEEP AND WILL SUPPORT A VERY UNSTABLE AIR MASS BY THE LATE MORNING FROM PORTIONS OF CENTRAL LA EWD TO JUST OFF THE CENTRAL GULF COAST. MID LEVEL WINDS ASSOCIATED WITH APPROACHING MID/UPPER LEVEL TROUGH WILL REMAIN SUFFICIENT FOR 40-50 KT DEEP LAYER SHEAR ACROSS THIS REGION. THEREFORE...EXPECT AN INCREASE IN SEVERE THREAT DURING THE MID TO LATE MORNING INTO PORTIONS OF CENTRAL LA AS HEATING COMMENCES AND COASTAL FRONT SHIFTS SLOWLY NWD. THOUGH OVERALL MODE MAY REMAIN LINEAR AS N-S ORIENTED OUTFLOW BOUNDARY SURGES EWD TODAY...SHEAR WILL BE SUFFICIENT FOR SUPERCELLS ESPECIALLY IF ACTIVITY DEVELOPS AHEAD OF ONGOING CONVECTIVE LINE OR LINE BECOMES MORE BROKEN. MESO LOW MAY FORM ALONG INTERSECTION OF OUTFLOW BOUNDARY AND E-W ORIENTED COASTAL FRONT SUPPORTING A THREAT OF TORNADOES GIVEN AMOUNT OF SHEAR. EASTERN AND NORTHERN EXTENT OF SUBSEQUENT SEVERE THREAT WILL BE MODULATED BY MORE LIMITED INSTABILITY ACROSS NRN LA AND EAST OF THE MS RIVER. ...SWRN TX TO THE MIDDLE TX COAST/DEEP SOUTH TX... OUTFLOW BOUNDARY WILL LIKELY SLOW ITS SWD MOTION FROM THE MIDDLE TX COAST TOWARDS THE BIG BEND REGION AND LIKELY LIFT SLOWLY NWD OR ERODE THIS AFTERNOON. AIR MASS REMAINS QUITE MOIST AND CONDITIONALLY VERY UNSTABLE FROM DEEP SOUTH TX INTO RIO GRANDE VALLEY SOUTH OF THIS OUTFLOW WITH SFC DEW POINTS IN THE LOWER 70S BELOW 8+ C/KM MID LEVEL LAPSE RATES. IN ADDITION...MODEST WNWLY FLOW ALOFT WILL SUPPORT 45-55 KT EFFECTIVE SHEAR THROUGH THE PERIOD. GIVEN STEEPNESS OF MID LEVEL LAPSE RATES AND AMOUNT OF MUCAPE...ELEVATED SEVERE THUNDERSTORMS INCLUDING SUPERCELLS MAY PERSIST THIS MORNING WITH A THREAT OF LARGE HAIL FROM THE TX HILL COUNTRY INTO THE COASTAL PLAIN. MORE VIGOROUS DEVELOPMENT IN THE FORM OF SUPERCELLS IS EXPECTED TO BE DRIVEN BY STRONG HEATING AND CONVERGENCE ALONG SURFACE OUTFLOW BOUNDARIES/COLD FRONT AND LEE TROUGH/DRY LINE FROM THE EDWARDS PLATEAU/BIG BEND REGION INTO THE LOWER RIO GRANDE VALLEY BY 20Z. GIVEN EXPECTED SHEAR...EXTREME INSTABILITY WILL SUPPORT A FEW INTENSE SUPERCELLS AGAIN LATE TODAY AND THIS EVENING SPREADING ESEWD. AS HAS BEEN THE CASE THE PAST FEW DAYS...VERY LARGE HAIL AND POSSIBLY A FEW TORNADOES WILL BE PRIMARY SEVERE THREATS. HOWEVER...AN INCREASED WIND THREAT MAY PERSIST THROUGH THE EVENING/OVERNIGHT AS ONE OR MORE MCSS EVOLVE. ..EVANS.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 16:36:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 12:36:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061634 SWODY1 SPC AC 061632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT SAT MAY 06 2006 VALID 061630Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS CENTRAL AND S TX.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS SRN LA.... ...TX/LA AREA... THE REMNANTS OF AN OVERNIGHT MCS...WITH A PROBABLE EMBEDDED MCV...ARE MOVING EWD ACROSS SW LA. E OF THE OUTFLOW ASSOCIATED WITH THIS CONVECTION...AN E-W ORIENTED BAROCLINIC ZONE EXTENDS ACROSS SE LA INTO THE EXTREME NE GULF OF MEXICO. THIS BOUNDARY MAY LIFT SLOWLY NWD IN ADVANCE OF THE LA MCS...WHICH WILL ALLOW A VERY MOIST AND MODERATELY UNSTABLE AIR MASS TO SPREAD INLAND ACROSS SRN LA. WHILE VERTICAL SHEAR WILL NOT BE PARTICULARLY STRONG IN THE WARM SECTOR...THERE WILL BE SOME ENHANCEMENT OF THE MID LEVEL FLOW ON THE SRN PERIPHERY OF THE MCV. EXPECT THE THREAT FOR AT LEAST ISOLATED DAMAGING WINDS AND LARGE HAIL TO PERSIST WITH LINE SEGMENTS AND POTENTIALLY SUPERCELLS E OF THE ONGOING ACTIVITY. THE MORE PRONOUNCED SUPERCELL THREAT WILL BE ALONG THE SURFACE BOUNDARY WHERE THE STRONGER LOW-LEVEL SHEAR AND INSTABILITY WILL COINCIDE...AND AN ISOLATED TORNADO OR TWO WILL BE POSSIBLE. ...CENTRAL/S TX AREA... OUTFLOW FROM THE MCS OVER LA/NW GULF CONTINUES TO MOVE SWWD TO S TX AND THE RIO GRANDE VALLEY. RESIDUAL INSTABILITY AND WAA ABOVE THE COLD POOL COULD MAINTAIN THE THREAT FOR STRONG/ISOLATED SEVERE STORMS INTO EARLY AFTERNOON NEAR THE MIDDLE TX COAST. THE MCS HAS STABILIZED MUCH OF E/SE TX...WHICH SHOULD LIMIT THE THREAT FOR ADDITIONAL SEVERE STORMS THIS AFTERNOON ACROSS EXTREME E/SE TX. FARTHER W...SOME LOW-LEVEL DESTABILIZATION WILL TAKE PLACE ACROSS CENTRAL TX WHERE THE CLOUD DEBRIS FROM THE MCS HAS CLEARED. THE MORE PROBABLE AREAS FOR ADDITIONAL DEVELOPMENT THIS AFTERNOON WILL BE ACROSS CENTRAL TX ALONG THE SE MOVING COLD FRONT /NEAR THE SRN FRINGE OF A SHORTWAVE TROUGH MOVING EWD FROM W TX/...AND ALONG THE OUTFLOW BOUNDARY ACROSS DEEP S TX AND THE RIO GRANDE VALLEY WHERE LIFT MAY BE SUFFICIENT TO OVERCOME A SUBSTANTIAL CAP. VERTICAL SHEAR AND INSTABILITY WILL BE SUFFICIENT FOR SUPERCELLS IN BOTH AREAS...WITH LARGE HAIL AND DAMAGING WINDS EXPECTED TO BE THE PRIMARY SEVERE THREATS. ..THOMPSON/CROSBIE.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 19:52:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 15:52:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061950 SWODY1 SPC AC 061949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SAT MAY 06 2006 VALID 062000Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER PORTIONS OF CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER THE CNTRL GULF COAST... ...CNTRL/SRN TX... COMPLEX SURFACE PATTERN EXISTS THIS AFTERNOON OWING TO MULTIPLE MESOSCALE BOUNDARIES REMNANT FROM EARLIER CONVECTION. MESOANALYSIS INDICATES WEAK SURFACE LOW NEAR JCT WITH ATTENDANT COLD FRONT EXTENDING SWWD TO W OF DRT. THIS BOUNDARY THEN STRETCHES NEWD INTO SERN OK...WITH ANOTHER BAROCLINIC ZONE EWD FROM THIS LOW INTO E-CNTRL TX NEAR LFK. HEATING AND FRONTAL CONVERGENCE COUPLED WITH GLANCING INFLUENCE OF VORTICITY/SPEED MAXIMUM TRANSLATING THROUGH NWRN TX ARE CONTRIBUTING TO SURFACE-BASED TSTM DEVELOPMENT ALONG FRONT FROM NEAR JCT SWWD TO NW OF DRT. CURRENT SAN ANTONIO VWP SHOWS SLY SURFACE WINDS VEERING TO WLY AT 50 KTS IN THE 5-6 KM AGL. WHILE MID-LEVEL LAPSE RATES ARE NOT PARTICULARLY STEEP...THE MODERATELY STRONG VERTICAL SHEAR AND MLCAPES OF 1000-2000 J/KG WILL SUPPORT ORGANIZED SEVERE STORMS...INCLUDING SUPERCELLS CAPABLE OF LOCALLY DAMAGING WINDS AND LARGE HAIL. STORMS WILL LIKELY INCREASE IN COVERAGE ALONG FRONT OVER THE EDWARDS PLATEAU INTO THE HILL COUNTRY WITH THE WIND AND HAIL THREAT SPREADING SEWD TOWARD THE COAST OVERNIGHT. ...CNTRL GULF COAST... MCS OVER THE LOWER MS VALLEY CONTINUES TO DECAY THIS AFTERNOON OVER SWRN MS INTO CNTRL LA. HOWEVER...ADDITIONAL STORMS HAVE RECENTLY DEVELOPED FARTHER TO THE E OF FAR SERN MS...NEAR WEAK FRONTAL BOUNDARY RETREATING NWD. VWP FROM THE NEW ORLEANS AREA INDICATES THAT WIND FIELDS ARE NOT PARTICULARLY STRONG...THOUGH THERE IS SOME VEERING WITH HEIGHT WHICH IS CONTRIBUTING TO 40-45 KTS OF DEEP-LAYER SHEAR. REGIONAL RADAR LOOP SHOWS THAT MCV WHICH SUPPORTED THIS MORNING/S MCS ORGANIZATION FARTHER TO THE W OVER THE SABINE VALLEY IS LIFTING MORE NEWD INTO CNTRL MS. THEREFORE...ADDITIONAL STORM DEVELOPMENT WILL HAVE TO BE DRIVEN BY WEAK LOW-LEVEL WAA AND CONVERGENCE ALONG PRE-EXISTING BOUNDARIES. STRONGEST STORMS WILL REMAIN CAPABLE OF LOCALLY DAMAGING WINDS AND PERHAPS AN ISOLATED TORNADO OR TWO INTO THIS EVENING. ..MEAD.. 05/06/2006  From swody1 at goshenarc.org Sun May 7 01:06:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 21:06:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070104 SWODY1 SPC AC 070102 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0802 PM CDT SAT MAY 06 2006 VALID 070100Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE HILL COUNTRY AND SEWD TOWARD THE MIDDLE TX COAST... ...CENTRAL AND ERN TX ACROSS THE GULF COAST... LIMITED SEVERE THREAT WILL PERSIST FROM TX ACROSS THE GULF COAST REGION OVERNIGHT...WHERE SUFFICIENT INSTABILITY AND MARGINAL SHEAR IS EVIDENT. GREATEST THREAT APPEARS TO EXIST FROM THE TX HILL COUNTRY ESEWD TOWARD THE COAST...WHERE 1000 T0 2000 J/KG MEAN-LAYER CAPE IS INDICATED. WITH LOW-LEVEL ESELYS BENEATH MODERATE MID-LEVEL WNWLYS...SHEAR SUFFICIENT FOR ORGANIZED/SUPERCELL STORMS EXISTS. THOUGH ALL MODEL GUIDANCE SUGGESTS A WEAKENING TREND WITH TIME ACROSS THIS REGION AS UPPER SUPPORT SLIDES BY TO THE N...WILL CONTINUE A SLIGHT RISK FORECAST -- AT LEAST INTO THIS EVENING. FURTHER E...STORMS ACROSS SRN MS/SRN AL ASSOCIATED WITH MCV REMNANTS HAVE SHOWN A WEAKENING TREND WITH TIME. THOUGH SOME THREAT EXISTS FOR A STRONGER STORM OR TWO TO PERSIST THROUGH THIS EVENING...OVERALL THREAT SHOULD CONTINUE TO WANE. ..GOSS.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 06:05:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 02:05:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070602 SWODY1 SPC AC 070600 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT SUN MAY 07 2006 VALID 071200Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL AND SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SERN CONUS... ...SYNOPSIS... LOW-AMPLITUDE MID-LEVEL SHORT-WAVE TROUGH IS FORECAST TO MOVE ACROSS THE SOUTHEAST THIS PERIOD...WHILE A SECOND TROUGH -- EXTENDING SWD ACROSS THE ERN ROCKIES -- MOVES EWD ACROSS THE PLAINS. AT THE SURFACE...W-E FRONT IS RETREATING NWD ACROSS THE CENTRAL GULF COAST STATES AHEAD OF UPPER TROUGH. A WEAK LOW SHOULD EVOLVE ALONG THIS BOUNDARY OVER NRN AL EARLY IN THE PERIOD...WITH A WEAK TRAILING COLD FRONT EXPECTED MOVE ACROSS THE SOUTHEAST THROUGH THE PERIOD. A WEAK COLD FRONT WILL ALSO MOVE ACROSS THE DAKOTAS...WHILE FURTHER S A LEE TROUGH MOVES ACROSS THE CENTRAL/SRN HIGH PLAINS. ...THE PLAINS... SHORT-WAVE RIDGING AND ASSOCIATED CAPPING INVERSION IS INITIALLY EXPECTED ACROSS THE PLAINS...WHICH SHOULD SUPPRESS ANY POTENTIAL FOR CONVECTION INTO THE AFTERNOON. NONETHELESS...LIMITED MOISTURE COMBINED WITH DAYTIME HEATING WILL ALLOW SOME DESTABILIZATION /1000 TO 1500 J/KG MEAN-LAYER CAPE/ TO OCCUR. AS UPPER TROUGH AND ASSOCIATED LOW-LEVEL FRONT/TROUGH MOVE INTO THE PLAINS...EXPECT ISOLATED STORMS TO DEVELOP BY LATE AFTERNOON -- FROM ND SWD INTO NERN NM/THE TX PANHANDLE. DEEP-LAYER WIND FIELD IS FORECAST TO BE SOMEWHAT WEAK FROM KS NWD...BUT SHEAR MAY BE SUFFICIENT FOR SOME MID-LEVEL ROTATION WITH STRONGER STORMS. WILL MAINTAIN THE SLIGHT RISK AREA OVER THE CENTRAL AND SRN HIGH PLAINS -- AS MODELS ARE IN GENERAL AGREEMENT THAT GREATEST CONVECTIVE COVERAGE -- AND THUS A RELATIVELY HIGHER COVERAGE OF SEVERE WEATHER -- SHOULD OCCUR OVER THIS REGION. FURTHER S INTO TX...SHEAR AND INSTABILITY ARE BOTH FORECAST TO BE STRONGER...BUT MORE PERSISTENT SHORT-WAVE RIDGING/LOW-LEVEL CAPPING SHOULD LIMIT STORM COVERAGE WITH SWD EXTENT. OVERNIGHT...40 KT SLY LOW-LEVEL JET IS FORECAST TO DEVELOP OVER CENTRAL TX/CENTRAL OK. THIS SHOULD SUPPORT AN INCREASE IN CONVECTION...WITH THE POTENTIAL FOR ONE OR MORE MCS TO EVOLVE AND MOVE SEWD ACROSS PARTS OF OK/TX. THOUGH LOSS OF HEATING/DECREASING INSTABILITY SUGGESTS A SLOW DECREASE IN SEVERE THREAT...LOCALLY-DAMAGING WINDS/HAIL COULD PERSIST INTO THE OVERNIGHT HOURS SHOULD MESOSCALE CONVECTIVE ORGANIZATION OCCUR. ...THE SOUTHEAST... SCATTERED SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING ACROSS MUCH OF THE REGION AT THE START OF THE PERIOD...AHEAD OF COLD FRONT AND ASSOCIATED SHORT-WAVE TROUGH. THE ONGOING/PERSISTENT PRECIPITATION SHOULD LIMIT POTENTIAL FOR DESTABILIZATION ACROSS MUCH OF THE REGION. ADDITIONALLY...VEERED/WLY LOW-LEVEL FLOW IS ANTICIPATED AHEAD OF FRONT...WHICH SHOULD LIMIT CONVERGENCE ALONG BOUNDARY. NONETHELESS...FAIRLY STRONG /AROUND 50 KT/ WLY MID-LEVEL JET IS FORECAST ALONG SRN FRINGE OF TROUGH...WHICH WILL CONTRIBUTE TO DEEP-LAYER SHEAR SUFFICIENT FOR ORGANIZED STORMS. THEREFORE...WILL MAINTAIN A LARGE SLIGHT RISK AREA OVER THE SERN CONUS -- MAINLY FOR ISOLATED STRONGER STORMS DEVELOPING WITHIN POCKETS OF LOCALLY GREATER INSTABILITY. ..GOSS.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 12:52:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 08:52:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071250 SWODY1 SPC AC 071248 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 AM CDT SUN MAY 07 2006 VALID 071300Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL GULF COAST AND SOUTHEAST... ...THERE IS A SLGT RISK OF SVR TSTMS INTO THE CENTRAL AND SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER SWRN TX... ...LOWER MS RIVER VALLEY ACROSS THE SOUTHEAST... BOUNDARY LAYER REMAINS QUITE MOIST AHEAD OF SHORTWAVE TROUGH NOW PROGRESSING EWD ACROSS THE CENTRAL GULF COAST STATES THIS MORNING WITH SURFACE DEW POINTS IN THE MID/UPPER 60S. WITH HEATING THIS SHOULD BE SUFFICIENT FOR MODERATE INSTABILITY EAST OF WEAK SURFACE LOW AND ASSOCIATED COLD FRONT FORECAST TO SHIFT EWD FROM CENTRAL AL INTO GA/SC TODAY. CONVERGENCE AND DEEP ASCENT ARE EXPECTED TO SUPPORT WIDESPREAD THUNDERSTORMS ACROSS THIS REGION THROUGH THE DAY...WITH SEVERE THREAT INCREASING IN BOTH INTENSITY AND COVERAGE WITH HEATING THIS MORNING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR WILL BE SUFFICIENT /I.E. EFFECTIVE SHEAR AROUND 40 KT/ FOR SUPERCELLS AND SMALL LINES...WITH PRIMARY SEVERE THREATS OF DAMAGING WINDS AND LARGE HAIL. ...PLAINS STATES... NARROW AXIS OF SURFACE-BASED INSTABILITY WILL DEVELOP TODAY OVER THE PLAINS ALONG WRN PERIPHERY OF LARGE SURFACE ANTICYCLONE CENTERED OVER THE NORTHEAST. FROM PORTIONS OF WRN TX INTO THE CENTRAL/ERN DAKOTAS...SLY LOW LEVEL FLOW WILL BECOME FOCUSED AHEAD OF A SURFACE TROUGH/COLD FRONT ADVANCING EWD OUT OF THE WRN PLAINS. MODELS HAVE BEEN CONSISTENT FOR SEVERAL RUNS IN INITIATING THUNDERSTORMS ALONG THIS FEATURE FROM CENTRAL/ERN ND INTO FAR ERN CO/WRN KS AND THE OK/TX PANHANDLES BY THE LATE AFTERNOON. ACTIVITY WILL INCREASE AHEAD OF A FAST MOVING SHORTWAVE TROUGH NOW SPREADING ACROSS THE NRN/CENTRAL ROCKIES WITH ASSOCIATED 25-35 KT WLY H5 FLOW INCREASING DEEP LAYER SHEAR AND SUPPORTING ORGANIZED CONVECTION. THOUGH AIR MASS IS NOT FORECAST TO DESTABILIZE SIGNIFICANTLY...BOUNDARY LAYER MOISTURE IS EXPECTED TO BE SUFFICIENT FOR MODEST MLCAPE NWD INTO PORTIONS OF WRN KS/NEB...WITH WEAKER INSTABILITY AND A DIMINISHED SEVERE THREAT NWD INTO THE DAKOTAS. SUPERCELLS AND MULTICELL CLUSTERS/LINES WILL EVOLVE EWD OUT OF THE CENTRAL/SRN HIGH PLAINS WITH THREATS OF ISOLATED LARGE HAIL/DAMAGING WINDS. SEVERE THREAT EXPECTED TO DIMINISH AFTER DARK...THOUGH THUNDERSTORM CLUSTERS WILL CONTINUE EWD FOR MUCH OF THE NIGHT. EXCEPTION MAY BE INTO PORTIONS OF WRN OK/NWRN TX ALONG NOSE OF 40 KT SLY LLJ WHICH IS FORECAST TO DEVELOP THIS EVENING. INTENSE STORMS/CLUSTERS OVER THE OK/TX PANHANDLE REGION AND SWRN KS/SERN CO MAY EVOLVE INTO A MCS WITH A MORE PERSISTENT SEVERE THREAT LINGERING SEWD INTO THE RED RIVER VALLEY THROUGH THE LATE EVENING. ...SWRN TX... STRONG HEATING WILL PROVIDE A VERY WEAK CAP ALONG NWRN EDGE OF RICH GULF MOISTURE EXPECTED TO NOSE INTO SWRN TX THIS AFTERNOON. 12Z SOUNDING AT DRT INDICATED ABUNDANT LOW LEVEL MOISTURE ALONG WITH A WEAK CAP. THOUGH CAPPING SHOULD INCREASE UNDER WLY FLOW ALOFT AS EVIDENCED BY 20C H85 TEMPS AT ELP THIS MORNING...SURFACE HEATING THROUGH THE 80S SHOULD WEAKEN CAP SUFFICIENTLY FOR A THREAT OF VIGOROUS UPDRAFTS LATER TODAY. SHEAR WILL REMAIN STRONG UNDER 40+ KT WLY MID LEVEL FLOW WITH FORECAST SOUNDINGS MAINTAINING EFFECTIVE SHEAR IN EXCESS OF 50 KT. THOUGH SEVERE THREAT IS MORE CONDITIONAL ACROSS THIS REGION GIVEN LACK OF LARGE SCALE ASCENT UNDER RIDGING ALOFT...FORECAST SOUNDINGS SUGGEST SUPERCELLS WOULD BE LIKELY SHOULD INITIATION OCCUR ALONG DRY LINE/WEAK LOW CENTER EXPECTED TO FORM OVER SWRN TX. LARGE HAIL WILL BE PRIMARY SEVERE THREAT...ALONG WITH ISOLATED DAMAGING WINDS. TORNADO POTENTIAL MAY BE MODULATED BY WEAK LOW LEVEL SHEAR FORECAST ACROSS THE AREA. ..EVANS/JEWELL.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 16:35:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 12:35:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071632 SWODY1 SPC AC 071631 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1131 AM CDT SUN MAY 07 2006 VALID 071630Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FROM SE AL TO SRN SC.... ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM W TX TO CENTRAL NEB.... ...SE STATES TODAY... CONVECTION IS ONGOING IN A BROKEN BAND ALONG THE SURFACE COLD FRONT FROM SE LA ACROSS SRN MS/AL INTO GA...AND IN ASSOCIATION WITH A MID LEVEL SHORTWAVE TROUGH MOVING EWD OVER NRN MS/AL. SURFACE HEATING/ DESTABILIZATION SHOULD ALLOW SOME OF THESE STORMS TO INTENSIFY DURING THE AFTERNOON ACROSS SE AL AND CENTRAL/S GA AND SRN SC. EXPECT THE THREAT FOR DAMAGING WINDS AND ISOLATED LARGE HAIL TO INCREASE GRADUALLY THROUGH EARLY-MID AFTERNOON...IN AN ENVIRONMENT OF MODERATE INSTABILITY /MLCAPE VALUES OF 1000-1500 J/KG/ AND MODEST DEEP LAYER VERTICAL SHEAR /0-6 KM SHEAR OF 35-40 KT/. ...W TX TO THE DAKOTAS THIS AFTERNOON INTO EARLY TONIGHT... MORNING UPPER AIR ANALYSES AND WATER VAPOR IMAGERY SHOW AN ELONGATED MID LEVEL TROUGH FROM NW NM/CO TO MT THAT IS MOVING EWD TOWARD THE HIGH PLAINS. THIS MID LEVEL TROUGH WILL BE ACCOMPANIED BY A WEAK COLD FRONT ACROSS THE DAKOTAS...AND A DEVELOPING LEE TROUGH FARTHER S FROM WRN NEB ACROSS ERN CO TO ERN NM. BOUNDARY LAYER DEWPOINTS ARE EXPECTED TO RANGE FROM THE UPPER 40S ACROSS THE CENTRAL/ERN DAKOTAS TO THE MID 50S INTO THE TX PANHANDLE THIS AFTERNOON E OF THE SURFACE BOUNDARIES...WHILE SURFACE TEMPERATURES WARM INTO THE 70S W OF THE MORNING STRATUS. THE NET RESULT WILL BE MLCAPE VALUES OF 500-1000 J/KG IN A NARROW CORRIDOR ACROSS THE WRN PLAINS. THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID-LATE AFTERNOON ALONG THE COLD FRONT AND LEE TROUGH...WITH THE STRONGER INSTABILITY AND VERTICAL SHEAR FROM NEB SWD SUPPORTING A SOMEWHAT GREATER THREAT FOR LARGE HAIL/DAMAGING WINDS COMPARED TO THE DAKOTAS. MUCH OF THIS ACTIVITY SHOULD BE DIURNAL WITH A DECREASING SEVERE THREAT BY LATE EVENING. HOWEVER...INCREASING MOISTURE FROM THE S AND THE DEVELOPMENT OF A 30-35 KT LLJ MAY ALLOW A CONVECTIVE CLUSTER TO PERSIST OVERNIGHT INVOF THE RED RIVER VALLEY OF SW OK/NW TX. ...SW TX THIS AFTERNOON/EARLY TONIGHT... A SRN STREAM SHORTWAVE TROUGH IS LOCATED OVER NRN BAJA...THOUGH THIS TROUGH SHOULD DRIFT SEWD THROUGH TONIGHT AND REMAIN W OF TX. STILL...L0W-LEVEL MOISTURE /DEWPOINTS OF 60-68/ IS SPREADING NWWD ALONG THE MIDDLE RIO GRANDE AND LOWER PECOS VALLEYS...AND THE 12Z DRT/MAF SOUNDINGS INDICATE THAT CONVECTIVE INHIBITION WILL BECOME WEAK ONCE SURFACE TEMPERATURES REACH THE LOW-MID 80S. A FEW STORMS MAY FORM OVER THE HIGHER TERRAIN OF SW TX AND W/SW OF DRT...AND THIS CONVECTION SHOULD THEN MOVE GENERALLY EWD. THOUGH MID LEVEL LAPSE RATES ARE NOT AS STEEP AS PREVIOUS DAYS OVER THIS AREA...MLCAPE OF 1000-2000 J/KG IS STILL EXPECTED IN COMBINATION WITH VERTICAL SHEAR SUPPORTIVE OF SUPERCELLS. LARGE HAIL SHOULD BE THE PRIMARY SEVERE THREAT...WITH ISOLATED VERY LARGE HAIL POSSIBLE WITH ANY SUPERCELLS. ..THOMPSON/TAYLOR.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 19:36:51 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 15:36:51 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071934 SWODY1 SPC AC 071932 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0232 PM CDT SUN MAY 07 2006 VALID 072000Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SERN ATLANTIC COAST INTO THE ERN FL PNHDL... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL AND SRN HIGH PLAINS... ...SC SWWD INTO SRN GA/NRN FL... MESOANALYSIS INDICATES SURFACE LOW OVER CNTRL SC AS OF 18Z WITH TRAILING COLD FRONT EXTENDING WSWWD THROUGH CNTRL PORTIONS OF GA AND AL INTO SERN MS. A MOIST AND MODERATELY UNSTABLE AIR MASS /MLCAPES OF 1000-1500 J/KG/...COUPLED WITH FORCING FOR ASCENT AHEAD OF SHORT WAVE TROUGH MOVING THROUGH THE TN VALLEY INTO THE SRN APPALACHIANS...HAS MAINTAINED STRONG/SEVERE CLUSTERS OF STORMS OVER CNTRL/SRN SC AND SWRN GA INTO THE FL PNHDL AND N-CNTRL FL. REGIONAL VWPS INDICATE LARGELY UNDIRECTIONAL 45-55 KT VERTICAL SHEAR...THOUGH LOW-LEVEL SHEAR IS LOCALLY STRONGER NEAR SC SURFACE LOW. EXPECT THE POTENTIAL FOR PRIMARILY DAMAGING WINDS AND LARGE HAIL TO CONTINUE THIS AFTERNOON INTO TONIGHT IN ASSOCIATION WITH BOWING LINE SEGMENTS AND EMBEDDED SUPERCELLS ACROSS SRN GA AND NRN FL. SOME THREAT OF ISOLATED TORNADOES WILL EXIST THROUGH THE AFTERNOON ALONG THE SC COAST WHERE LOW-LEVEL HODOGRAPHS WILL REMAIN MORE STRONGLY CURVED. ...SWRN TX... WRN EXTENSION OF SYNOPTIC FRONT HAS STARTED TO RETREAT NWD THROUGH WRN TX THIS AFTERNOON WITH MESOANALYSIS DEPICTING THIS BOUNDARY FROM FAR SERN NM SEWD TO NEAR SAT AS OF 18Z. AIR MASS S OF FRONT REMAINS RELATIVELY MOIST AND MODERATELY UNSTABLE WITH DEWPOINTS IN THE UPPER 50S TO MID 60S...CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. VISIBLE SATELLITE IMAGERY INDICATES THAT CUMULUS DEVELOPMENT IS DEEPENING ALONG THE HIGHER TERRAIN OF SWRN TX /GLASS AND DAVIS MOUNTAINS/ ALONG WRN EDGE OF INSTABILITY AXIS. CONTINUED HEATING AND OROGRAPHIC FORCING SHOULD SUPPORT ISOLATED TO WIDELY SCATTERED STORM DEVELOPMENT BY MID TO LATE AFTERNOON WITH STORMS MOVING OFF THE HIGH TERRAIN INTO A PROGRESSIVELY MORE UNSTABLE ENVIRONMENT. SELY SURFACE WINDS BENEATH 40-50 KTS AT 6 KM AND 90-100 KTS AT 9 KM AGL /PER WHITE SANDS NM PROFILER/ WILL SUPPORT SUPERCELLS CAPABLE OF PRIMARILY LARGE HAIL. THOUGH NOT AS LIKELY...ADDITIONAL ISOLATED STORM DEVELOPMENT MAY ALSO OCCUR ALONG RETREATING WARM FRONT OVER THE NRN/CNTRL PERMIAN BASIN INTO SERN NM...PERHAPS SEWD INTO THE CONCHO VALLEY WHERE ENVIRONMENT WOULD ALSO BE SUPPORTIVE OF SUPERCELLS. ...SWRN NEB INTO THE TX PNHDL... AFTERNOON WATER VAPOR IMAGERY SHOWS SHORT WAVE TROUGH TRANSLATING EWD INTO THE CNTRL HIGH PLAINS...WHICH COUPLED WITH RATHER STEEP LOW AND MID-LEVEL LAPSE RATES...IS SUPPORTING CONVECTIVE DEVELOPMENT NEAR GLD. DESPITE MODEST SURFACE DEWPOINTS IN THE UPPER 40S TO LOWER 50S...CONTINUED DAYTIME HEATING AND THESE LAPSE RATES SHOULD CONTRIBUTE TO MLCAPES OF 500-1000 J/KG BY LATE AFTERNOON. TSTMS ARE EXPECTED TO INCREASE IN COVERAGE ALONG LEE TROUGH OR WEAK DRY LINE FROM SWRN NEB INTO THE TX PNHDL THIS AFTERNOON AND EVENING. TUCUMCARI NM AND GRENADA CO PROFILERS BOTH INDICATE ROUGHLY 30-35 KT MID-LEVEL FLOW WITH A NOTICEABLY STRONGER INCREASE AT HIGH-LEVELS /100-110 KTS/ FARTHER S ACROSS NERN NM AND THE TX PNHDL. MARGINAL SHEAR ACROSS NRN PORTION OF SLIGHT RISK AREA WILL LARGELY SUPPORT MULTICELLULAR CONVECTION CAPABLE OF GUSTY WINDS AND LARGE HAIL. HOWEVER...FARTHER S FROM SWRN KS INTO THE TX PNHDL...SUPERCELLS APPEAR MORE LIKELY WITH A THREAT OF PRIMARILY LARGE HAIL. ...WRN AND CNTRL DAKOTAS... RADAR IMAGERY SHOWS TSTMS INCREASING IN COVERAGE THIS AFTERNOON ALONG COLD FRONT FROM THE BLACK HILLS NEWD INTO CNTRL ND WITHIN ENVIRONMENT CHARACTERIZED BY STEEP LOW AND MID-LEVEL LAPSE RATES AND MLCAPES OF 500 J/KG. VERTICAL SHEAR REMAINS RELATIVELY WEAK...THOUGH THE PRESENCE OF THE STEEP LAPSE RATES MAY PROMOTE LOCALLY STRONG WIND GUSTS AND MARGINAL HAIL WITH THE STRONGEST STORMS. ..MEAD.. 05/07/2006  From swody1 at goshenarc.org Mon May 8 01:03:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 21:03:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080101 SWODY1 SPC AC 080059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT SUN MAY 07 2006 VALID 080100Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SWRN KS SWD ACROSS TX... ...CENTRAL HIGH PLAINS SWD TO THE RIO GRANDE... THUNDERSTORMS CONTINUE TO INCREASE IN COVERAGE OVER SWRN KS AND THE TX/OK PANHANDLES...WHILE OTHER STORMS PERSIST ACROSS PARTS OF THE TRANSPECOS AND INTO THE TX BIG BEND/RIO GRANDE VALLEY. EVENING MAF RAOB REVEALS FAVORABLE KINEMATIC AND THERMODYNAMIC ENVIRONMENT FOR SEVERE/SUPERCELL STORMS. THREAT FOR LARGE HAIL AND DAMAGING WINDS -- AND PERHAPS AN ISOLATED TORNADO -- SHOULD CONTINUE THIS EVENING...WHILE SPREADING EWD TOWARD CENTRAL TX AS LOW-LEVEL JET/WARM ADVECTION INCREASES AHEAD OF APPROACHING UPPER TROUGH. THOUGH CONDITIONS ARE SLIGHTLY LESS FAVORABLE NWD INTO SWRN KS...DEVELOPING LOW-LEVEL JET SHOULD ALLOW CONVECTION TO PERSIST/INCREASE WHILE MOVING SEWD ACROSS THE HIGH PLAINS AND INTO PARTS OF OK/N TX. PRIMARY THREAT WILL BE HAIL AND LOCALLY DAMAGING GUSTS...WITH STORMS ACROSS THIS AREA LIKELY CONTINUING THROUGH THE PERIOD. ...THE SOUTHEAST... CLUSTER OF SEVERE STORMS HAS MOVED OFF THE SC COAST...THOUGH NEW STORMS CONTINUE TO DEVELOP ACROSS CENTRAL GA NEAR INTERSECTION OF WEDGE FRONT AND COLD FRONT...AND SWWD INTO SRN AL ALONG COLD FRONT. HOWEVER...DESPITE SUFFICIENT WIND FIELD...EVENING SOUNDINGS REVEAL WEAK LAPSE RATES/LIMITED INSTABILITY...AND THEREFORE EXPECT SEVERE THREAT ACROSS THIS REGION TO REMAIN LIMITED AS WELL. THOUGH A FEW MARGINAL SEVERE REPORTS WILL BE POSSIBLE THROUGH THIS EVENING...SLOW STABILIZATION OF AIRMASS SHOULD RESULT IN A CONTINUED DECREASE IN THREAT...AND THUS WILL DROP THE SLIGHT RISK AND CARRY ONLY LOW SEVERE PROBABILITIES THROUGH THE REMAINDER OF THE PERIOD. ...NRN PLAINS... THUNDERSTORMS CONTINUE ACROSS THE DAKOTAS AND INTO NEB AHEAD OF COLD FRONT...WHERE 1000 TO 1500 J/KG MEAN-LAYER CAPE PERSISTS. HOWEVER...DEEP-LAYER SHEAR AHEAD OF FRONT -- PARTICULARLY ACROSS THE DAKOTAS -- REMAINS WEAK. THIS COMBINED WITH BOUNDARY LAYER STABILIZATION OVERNIGHT SUGGESTS THAT ANY REMAINING SEVERE THREAT SHOULD WANE THROUGH THE EVENING. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 13:02:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 09:02:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081259 SWODY1 SPC AC 081257 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 AM CDT MON MAY 08 2006 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL/ERN TX INTO NRN FL... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN/CENTRAL PLAINS... ...LA EWD ACROSS THE CENTRAL GULF COAST/NRN FL... BOUNDARY LAYER AIR MASS IS VERY MOIST ALONG AND SOUTH OF STALLED SURFACE FRONT EXTENDING FROM FAR SRN GA/NRN FL WWD INTO SERN TX THIS MORNING. SURFACE DEW POINTS IN THE LOW TO MID 70S WERE OBSERVED ALONG AND JUST OFF THE GULF COAST. THIS BOUNDARY WILL MOVE LITTLE THROUGH THE DAY WHILE MODERATE TO STRONG WLY MID LEVEL FLOW PERSISTS FROM THE SRN PLAINS INTO NRN FL...WITH H5 WINDS FROM 40-50 KT. THOUGH MID LEVEL LAPSE RATES REMAIN MODEST...ABUNDANT MOISTURE WILL SUPPORT STRONG INSTABILITY BY THE EARLY AFTERNOON ACROSS THE CENTRAL GULF COAST WITH LESSER INSTABILITY FORECAST INTO NRN FL. DESPITE ILL-DEFINED FOCUSING MECHANISMS ALOFT ON MORNING WV IMAGERY... HEATING AND CONVERGENCE INVOF SURFACE FRONT AND SEA-BREEZES SHOULD SUPPORT WIDESPREAD STRONG TO SEVERE THUNDERSTORMS ACROSS THIS REGION BY THE LATE MORNING/EARLY AFTERNOON. EFFECTIVE SHEAR WILL REMAIN SUPPORTIVE OF SUPERCELLS AND ORGANIZED MULTICELL CLUSTERS/LINES AS ACTIVITY INCREASES THROUGH THE DAY BOTH IN COVERAGE AND INTENSITY. DAMAGING WINDS AND LARGE HAIL ARE EXPECTED TO BE PRIMARY SEVERE THREATS...THOUGH FORECAST STORM MOTIONS ALONG STALLED SURFACE BOUNDARY MAY SUPPORT A TORNADO OR TWO WHERE LOW LEVEL SHEAR CAN BE MAXIMIZED JUST NORTH OF THE FRONT. ...CENTRAL/ERN TX INTO WRN LA... STRONG HEATING WILL DEVELOP ACROSS WRN AND CENTRAL TX TODAY AND ALLOW DRY LINE TO MIX WELL EWD...POSSIBLY INTO THE I-35 CORRIDOR BY LATE IN THE DAY. LARGE SCALE ASCENT WILL REMAIN WEAK ACROSS THE REGION THOUGH STRONG HEATING AND CONVERGENCE ALONG DRY LINE AND PERSISTENT OUTFLOW BOUNDARIES SHOULD SUPPORT RAPID THUNDERSTORM DEVELOPMENT AS CAP WEAKENS LATE THIS AFTERNOON AND EVENING. FORECAST SOUNDINGS INDICATE AN EXTREMELY UNSTABLE WARM SECTOR GIVEN UPPER 60F/LOWER 70F SURFACE DEW POINTS EXPECTED TO SPREAD NWD TODAY...WITH MLCAPE IN EXCESS OF 3000 J/KG BY 21Z. IN ADDITION... 45+ KT OF DEEP LAYER SHEAR WILL REMAIN MORE THAN ADEQUATE FOR SUPERCELLS PRODUCING VERY LARGE HAIL...ALONG WITH DAMAGING WINDS AND POSSIBLY ISOLATED TORNADOES. ...NRN MS RIVER VALLEY ACROSS THE CENTRAL PLAINS... SURFACE COLD FRONT WILL ADVANCE EWD ACROSS THE NRN PLAINS AND SEWD INTO THE CENTRAL PLAINS TODAY AHEAD OF NEXT IN A SERIES OF FAST MOVING SHORTWAVE TROUGHS MOVING ACROSS THE CENTRAL/NRN ROCKIES. THOUGH LOW LEVEL MOISTURE WILL REMAIN MODEST...50+ F SURFACE DEW POINTS WILL BE SUFFICIENT FOR NARROW AXIS OF MARGINAL TO MODERATE INSTABILITY ALONG AND AHEAD OF THIS FRONT GIVEN STEEP LAPSE RATES. EXPECT SEVERAL CLUSTERS/LINES AND SUPERCELLS WILL DEVELOP LATER TODAY...WITH MORE CONCENTRATED/INTENSE DEVELOPMENT EXPECTED ACROSS THE MID MO RIVER VALLEY INTO CENTRAL KS WHERE MLCAPE AND CONVERGENCE ALONG WEAK SURFACE LOW WILL BE GREATER. LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE THREATS. FORECAST SOUNDINGS AND SUB-60F SURFACE DEW POINTS SUGGEST TORNADO THREAT MAY BE MITIGATED A BIT BY RELATIVELY HIGH LCLS THIS AFTERNOON. HOWEVER...PRESENCE OF SURFACE LOW AND MODEST SLY LLJ WILL SUPPORT SUFFICIENT LOW LEVEL SHEAR FOR INCLUSION OF TORNADO PROBABILITIES INTO THE CENTRAL PLAINS. ACTIVITY OVER SERN NEB/KS SHOULD EVOLVE INTO ONE OR MORE MCS/S AND SHIFT SEWD OVERNIGHT ALONG NOSE OF INCREASING SWLY LLJ ACROSS THE OZARK PLATEAU/NERN OK WITH ATTENDANT THREAT OF LARGE HAIL AND ISOLATED DAMAGING WINDS. ..EVANS/JEWELL.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 16:38:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 12:38:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081633 SWODY1 SPC AC 081632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT MON MAY 08 2006 VALID 081630Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS THE GULF COAST INTO CENTRAL TX.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO TONIGHT ACROSS THE CENTRAL PLAINS.... ...CENTRAL KS TO ERN NEB THIS AFTERNOON/EVENING... A SURFACE LEE TROUGH/DRYLINE WILL BECOME BETTER DEFINED THIS AFTERNOON FROM ERN NEB TO CENTRAL KS...S OF A WEAK TRIPLE POINT LOW INVOF NE NEB. STEEP MID LEVEL LAPSE RATES OVER THE HIGH PLAINS THIS MORNING WILL SPREAD EWD OVER THE CENTRAL PLAINS BY AFTERNOON...ABOVE A WARMING AND GRADUALLY MOISTENING BOUNDARY LAYER WITH AFTERNOON TEMPERATURES OF 75-80 F AND DEWPOINTS RANGING FROM THE UPPER 50S IN ERN NEB TO LOWER 60S IN KS. THIS WILL RESULT IN AFTERNOON MLCAPE VALUES OF 1500-2500 J/KG ALONG AND E OF THE SURFACE TROUGH. THUNDERSTORM INITIATION IS ANTICIPATED IN THE 21-23Z TIME FRAME ALONG THE SURFACE TROUGH FROM SE NEB INTO CENTRAL KS...AS A SUBTLE MID LEVEL WAVE PROGRESSES EWD OVER THE CENTRAL/NRN PLAINS IN ADVANCE OF THE PRIMARY TROUGH OVER THE NRN ROCKIES. VERTICAL SHEAR/ INSTABILITY AND SHEAR VECTOR/BOUNDARY ORIENTATIONS APPEAR SUFFICIENT FOR DISCRETE SUPERCELLS THE FIRST FEW HOURS AFTER INITIATION. LATER IN THE EVENING...CONVECTION MAY GROW UPSCALE INTO ONE OR MORE MCS/S AND MOVE ESEWD TOWARD WRN MO AND N/NE OK. VERY LARGE HAIL AND A COUPLE OF TORNADOES WILL BE POSSIBLE WITH THE AFTERNOON/EVENING SUPERCELLS...WHILE WIND DAMAGE AND LARGE HAIL SHOULD BECOME THE MAIN THREATS BY TONIGHT...PRIMARILY ALONG THE SRN FLANK OF ANY CONVECTIVE CLUSTERS. ...GULF COAST THIS AFTERNOON... A STALLED BAROCLINIC ZONE NEAR THE I-10 CORRIDOR WILL SERVE AS A FOCUS FOR THUNDERSTORM DEVELOPMENT THROUGH THE AFTERNOON FROM SRN LA EWD TO N FL/EXTREME S GA. MORNING SOUNDINGS ACROSS THIS AREA SHOW THE POTENTIAL FOR MLCAPE VALUES OF 1500-2000 J/KG WITH DAYTIME HEATING...AND RELATIVELY WEAK CONVECTIVE INHIBITION. GIVEN THE MODERATE INSTABILITY AND STRONGER MID-UPPER LEVEL FLOW...STORMS WITH SOME SUPERCELL CHARACTERISTICS WILL BE POSSIBLE. HOWEVER...MID LEVEL LAPSE RATES ARE RATHER MODEST /6.5 C/KM/ AND LOW-LEVEL FLOW/SHEAR IS ALSO RELATIVELY WEAK...AND BOTH OF THESE FACTORS MAY TEND TO LIMIT THE SEVERE THREAT SOMEWHAT. ISOLATED/MARGINAL DAMAGING WINDS AND HAIL ARE EXPECTED TO BE THE MAIN THREATS THROUGH THE AFTERNOON. ...TX AREA THIS AFTERNOON/EVENING... SUBSTANTIAL UNCERTAINTY EXISTS REGARDING CONVECTIVE INITIATION THIS AFTERNOON ACROSS TX. THE OUTFLOW FROM AN EARLIER CONVECTIVE CLUSTER IS NOW BECOMING DIFFUSE FROM N CENTRAL INTO E CENTRAL TX...AND THIS RESIDUAL OUTFLOW IS MASKING THE LOCATION OF THE WEAKENING BAROCLINIC ZONE ACROSS TX. MODIFIED MORNING SOUNDINGS /AS WELL AS SHORT TERM MODEL FORECASTS/ SHOW THE POTENTIAL FOR MLCAPE OF 3000-4000 J/KG THIS AFTERNOON ACROSS CENTRAL TX...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. ISOLATED THUNDERSTORMS MAY DEVELOP ALONG THE RESIDUAL OUTFLOW...AND PERHAPS OVER CENTRAL TX NEAR THE OUTFLOW/DRYLINE MERGER AND SWD ALONG THE DRYLINE. IF STORMS DO FORM...VERY LARGE HAIL WILL BE POSSIBLE. ..THOMPSON/TAYLOR.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 20:15:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 16:15:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 082011 SWODY1 SPC AC 082010 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0310 PM CDT MON MAY 08 2006 VALID 082000Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN FL WWD ALONG THE GULF COAST AND ACROSS PARTS OF THE LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL AND SRN PLAINS... ...GULF COAST... STORMS WERE CONSOLIDATING ALONG STALLED FRONTAL ZONE FROM SRN GA/NERN FL WWD ACROSS THE FL PNHDL. ADDITIONAL ACTIVITY MAY FORM INVOF THIS BOUNDARY OVER THE NEXT SEVERAL HOURS FROM MOBILE AREA WWD/NWWD INTO LA. HOWEVER...STORM COVERAGE WITH WWD EXTENT MAY BE SOMEWHAT MORE LIMITED BY LACK OF STRONGER LARGE SCALE FORCING FOR UPWARD VERTICAL MOTION. MOIST AND VERY UNSTABLE AIR MASS ALONG THE BOUNDARY WILL CONTINUE TO FUEL STOUT UPDRAFTS. WHILE LOW LEVEL FLOW/SHEAR REMAINS SOMEWHAT WEAK...DEEP LAYER SHEAR IS MORE THAN ADEQUATE FOR UPDRAFT PERSISTENCE GIVEN 50KT MID LEVEL FLOW. STRONG CELLS/MULTICELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND SOME HAIL. GIVEN GENERALLY WEAK LARGE SCALE FORCING...DIURNAL WEAKENING SHOULD COMMENCE WITHIN A FEW HOUR AFTER SUNSET. ...CNTRL/SRN PLAINS... COLD FRONT CURRENTLY SITUATED FROM ERN SD SWWD ACROSS CNTRL NEB INTO NWRN KS IS EXPECTED TO BECOME A FOCUS FOR TSTM DEVELOPMENT BY LATE AFTERNOON. DRYLINE EXTENDS SWWD FROM THE COLD FRONT...FROM WRN KS TO TX BIG BEND AREA. WATER VAPOR IMAGERY LOOP DEPICTS A NUMBER OF SHORT WAVE FEATURES SPREADING ESEWD FROM THE ROCKIES TOWARD THE PLAINS AND LIFT ASSOCIATED WITH THESE IMPULSES SHOULD FURTHER AID STORM DEVELOPMENT NEAR THE FRONT AND DRYLINE THROUGH THIS EVENING. AT PRESENT...WARM SECTOR OVER TX REMAINS CAPPED. HOWEVER...VERY STRONG HEATING AHEAD OF THE DRYLINE SHOULD PROMOTE AT LEAST ISOLATED STORM INITIATION ACROSS WRN/NWRN TX. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS ACTIVITY WILL REMAIN ISOLATED THROUGH THIS PERIOD AS STRONGER LARGE SCALE FORCING REMAINS TO THE NORTH NEAR THE COLD FRONT. AS THE COLD FRONT DEVELOPS EAST ACROSS KS/NEB AREA THROUGH THIS EVENING...RESULTING LIFT WILL ACT ON INCREASINGLY MOIST AND UNSTABLE AIR MASS. STORMS...IN CLUSTERS AND LINE SEGMENTS...WITH SOME SUPERCELL POTENTIAL...WILL DEVELOP EAST ACROSS ERN NEB AND CNTRL AND ERN KS. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. WEAK WAVE ALONG THE FRONT OVER NEB...AND GREATER INSTABILITY AHEAD OF THE FRONT OVER KS... MAY FOSTER GREATER LOW LEVEL SHEAR/STRETCHING WITH AN ENHANCED TORNADO THREAT POSSIBLY EVOLVING IN THESE AREAS. CONVECTION SHOULD MERGE INTO AN MCS OR TWO FROM ERN KS INTO WRN IA THROUGH LATE EVENING WITH SOME SEVERE HAIL/WIND THREAT CONTINUING. SEVERE POTENTIAL MAY PERSIST WITH THE MCS FORECAST TO DEVELOP INTO SERN KS/NERN OK AND WRN MO/AR THROUGH EARLY TUESDAY WHERE GREATER INSTABILITY AND FORCING WILL EXIST ON THE NOSE OF INTENSIFYING LOW LEVEL JET. ...MN... ISOLATED STRONG STORMS WERE DEVELOPING WITHIN WEAK INSTABILITY AXIS AHEAD OF THE COLD FRONT OVER WRN/NCNTRL MN. WHILE LOW STATIC STABILITY AND MODEST FORCING SHOULD MAINTAIN CONVECTION...MID LEVEL FLOW IS FORECAST TO WEAKEN WITHIN MID LEVEL TROUGH AXIS THROUGH THE EVENING. HAIL APPEARS TO BE THE MAIN SEVERE WEATHER THREAT WITH THIS ACTIVITY OVER THE NEXT FEW HOURS. ..CARBIN.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 21:16:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 17:16:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 082111 SWODY1 SPC AC 082109 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0409 PM CDT MON MAY 08 2006 VALID 082000Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN FL WWD ALONG THE GULF COAST AND ACROSS PARTS OF THE LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL AND SRN PLAINS... CORRECTED FOR NDFD GRID POINTS PRODUCT ...GULF COAST... STORMS WERE CONSOLIDATING ALONG STALLED FRONTAL ZONE FROM SRN GA/NERN FL WWD ACROSS THE FL PNHDL. ADDITIONAL ACTIVITY MAY FORM INVOF THIS BOUNDARY OVER THE NEXT SEVERAL HOURS FROM MOBILE AREA WWD/NWWD INTO LA. HOWEVER...STORM COVERAGE WITH WWD EXTENT MAY BE SOMEWHAT MORE LIMITED BY LACK OF STRONGER LARGE SCALE FORCING FOR UPWARD VERTICAL MOTION. MOIST AND VERY UNSTABLE AIR MASS ALONG THE BOUNDARY WILL CONTINUE TO FUEL STOUT UPDRAFTS. WHILE LOW LEVEL FLOW/SHEAR REMAINS SOMEWHAT WEAK...DEEP LAYER SHEAR IS MORE THAN ADEQUATE FOR UPDRAFT PERSISTENCE GIVEN 50KT MID LEVEL FLOW. STRONG CELLS/MULTICELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND SOME HAIL. GIVEN GENERALLY WEAK LARGE SCALE FORCING...DIURNAL WEAKENING SHOULD COMMENCE WITHIN A FEW HOUR AFTER SUNSET. ...CNTRL/SRN PLAINS... COLD FRONT CURRENTLY SITUATED FROM ERN SD SWWD ACROSS CNTRL NEB INTO NWRN KS IS EXPECTED TO BECOME A FOCUS FOR TSTM DEVELOPMENT BY LATE AFTERNOON. DRYLINE EXTENDS SWWD FROM THE COLD FRONT...FROM WRN KS TO TX BIG BEND AREA. WATER VAPOR IMAGERY LOOP DEPICTS A NUMBER OF SHORT WAVE FEATURES SPREADING ESEWD FROM THE ROCKIES TOWARD THE PLAINS AND LIFT ASSOCIATED WITH THESE IMPULSES SHOULD FURTHER AID STORM DEVELOPMENT NEAR THE FRONT AND DRYLINE THROUGH THIS EVENING. AT PRESENT...WARM SECTOR OVER TX REMAINS CAPPED. HOWEVER...VERY STRONG HEATING AHEAD OF THE DRYLINE SHOULD PROMOTE AT LEAST ISOLATED STORM INITIATION ACROSS WRN/NWRN TX. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS ACTIVITY WILL REMAIN ISOLATED THROUGH THIS PERIOD AS STRONGER LARGE SCALE FORCING REMAINS TO THE NORTH NEAR THE COLD FRONT. AS THE COLD FRONT DEVELOPS EAST ACROSS KS/NEB AREA THROUGH THIS EVENING...RESULTING LIFT WILL ACT ON INCREASINGLY MOIST AND UNSTABLE AIR MASS. STORMS...IN CLUSTERS AND LINE SEGMENTS...WITH SOME SUPERCELL POTENTIAL...WILL DEVELOP EAST ACROSS ERN NEB AND CNTRL AND ERN KS. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. WEAK WAVE ALONG THE FRONT OVER NEB...AND GREATER INSTABILITY AHEAD OF THE FRONT OVER KS... MAY FOSTER GREATER LOW LEVEL SHEAR/STRETCHING WITH AN ENHANCED TORNADO THREAT POSSIBLY EVOLVING IN THESE AREAS. CONVECTION SHOULD MERGE INTO AN MCS OR TWO FROM ERN KS INTO WRN IA THROUGH LATE EVENING WITH SOME SEVERE HAIL/WIND THREAT CONTINUING. SEVERE POTENTIAL MAY PERSIST WITH THE MCS FORECAST TO DEVELOP INTO SERN KS/NERN OK AND WRN MO/AR THROUGH EARLY TUESDAY WHERE GREATER INSTABILITY AND FORCING WILL EXIST ON THE NOSE OF INTENSIFYING LOW LEVEL JET. ...MN... ISOLATED STRONG STORMS WERE DEVELOPING WITHIN WEAK INSTABILITY AXIS AHEAD OF THE COLD FRONT OVER WRN/NCNTRL MN. WHILE LOW STATIC STABILITY AND MODEST FORCING SHOULD MAINTAIN CONVECTION...MID LEVEL FLOW IS FORECAST TO WEAKEN WITHIN MID LEVEL TROUGH AXIS THROUGH THE EVENING. HAIL APPEARS TO BE THE MAIN SEVERE WEATHER THREAT WITH THIS ACTIVITY OVER THE NEXT FEW HOURS. ..CARBIN.. 05/08/2006  From swody1 at goshenarc.org Tue May 9 01:09:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 21:09:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 090107 SWODY1 SPC AC 090106 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT MON MAY 08 2006 VALID 090100Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDDLE MO VALLEY SWWD INTO OK/NWRN AR... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL GULF COAST REGION... ...MID MO VALLEY SWWWD INTO KS/NRN OK/ERN MO/NWRN AR... LINE OF STORMS HAS EVOLVED FROM ERN NEB SWWD INTO SWRN KS...WITH EMBEDDED LEWP/BOW-TYPE STRUCTURES. STORMS SHOULD CONTINUE/INCREASE OVERNIGHT AS LOW-LEVEL JET STRENGTHENS...AND SPREAD ESEWD INTO WRN MO/NRN OK/NWRN AR. THOUGH DEEP-LAYER WIND FIELD IS NOT OVERLY STRONG...SHEAR IS SUFFICIENT FOR A CONTINUATION OF ORGANIZED STORMS AND A THREAT FOR MAINLY HAIL/DAMAGING WINDS THROUGH THE END OF THE PERIOD. ...CENTRAL GULF COAST REGION... THUNDERSTORMS -- INCLUDING A FEW SUPERCELLS -- HAVE INCREASED RECENTLY ACROSS ERN LA/SRN MS/SRN AL WITHIN MOIST/MODERATELY UNSTABLE AIRMASS. EVENING LIX /SLIDELL LA/ RAOB INDICATED 60 KT WNWLY MID-LEVEL FLOW...CONTRIBUTING TO DEEP-LAYER SHEAR VERY FAVORABLE FOR SUPERCELLS. EXPECT POTENTIAL FOR LARGE HAIL AND LOCALLY DAMAGING WINDS -- AND ISOLATED TORNADOES -- THROUGH THIS EVENING...THOUGH SEVERE THREAT SHOULD EXHIBIT A DIURNALLY-DRIVEN DECREASE LATE THIS EVENING/OVERNIGHT. ..GOSS.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 12:40:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 08:40:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 091237 SWODY1 SPC AC 091235 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0735 AM CDT TUE MAY 09 2006 VALID 091300Z - 101200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF ERN OK AND NWRN AR... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OK/TX PANHANDLE REGION TO THE CENTRAL GULF COAST... ...SYNOPSIS... A SERIES OF FAST MOVING SHORTWAVE TROUGHS ARE EVIDENT ON WV IMAGERY THIS MORNING EJECTING AWAY FROM BROADER MID/UPPER LEVEL TROUGH OVER THE ROCKIES. ONE SYSTEM IS NOW MOVING ACROSS CENTRAL TX AND WILL OVERSPREAD THE LOWER MS RIVER VALLEY/CENTRAL GULF COAST REGION TODAY. ANOTHER APPEARS TO BE MOVING INTO THE CENTRAL ROCKIES WHICH IS FORECAST TO BECOME BETTER DEFINED AS IT SHIFTS ACROSS THE SRN HIGH PLAINS AND OVER OK/KS LATER TONIGHT. AT THE SURFACE...PRIMARY COLD FRONT NOW EXTENDS FROM CENTRAL IA INTO W-CENTRAL TX WHICH HAS BEEN CONVECTIVELY-REINFORCED ACROSS NERN/CENTRAL OK FROM ONGOING MCS NOW MOVING INTO THE OZARK REGION. IN ADDITION...WEAK LOW CENTER WAS ANALYZED OVER SWRN OK ALONG COLD FRONT/DRY LINE TRIPLE POINT...WITH WARM FRONT DELINEATING VERY MOIST/MARINE AIR EXTENDING FROM SRN LA INTO CENTRAL OK. ...SRN HIGH PLAINS INTO THE LOWER MS RIVER VALLEY/MID SOUTH... FORECAST REMAINS COMPLEX THIS MORNING DUE TO UNCERTAINTY ABOUT EFFECTS OF ONGOING MCS. 09Z RUC MAINTAINS SSWLY LLJ INTO NRN AR THROUGH THE MORNING AND SHOULD SUPPORT CONTINUED STRONG/SEVERE THUNDERSTORMS ACROSS THE OZARK PLATEAU AND NRN AR WITH THREATS OF LARGE HAIL AND DAMAGING WINDS. ACTIVITY MAY INTENSIFY INTO THE BOOTHEEL REGION OF MO/MID SOUTH LATER THIS MORNING/EARLY THIS AFTERNOON ALONG NOSE OF THIS JET AS MODERATE INSTABILITY DEVELOPS. VERTICAL MOTION SHOULD BECOME QUITE WEAK ACROSS THE REGION FOR MUCH OF THE DAY...THOUGH ABUNDANT MOISTURE WITH SURFACE DEW POINTS IN THE LOWER TO MID 70S AND VERY STEEP LAPSE RATES WILL SUPPORT EXTREMELY UNSTABLE AIR MASS. HOWEVER...AREA WILL BE STRONGLY CAPPED UNDER 10-12C H7 TEMPERATURES. ISOLATED DIURNAL THUNDERSTORMS MAY DEVELOP IF CAP CAN BE BREACHED LATER TODAY ALONG THE NUMEROUS SURFACE BOUNDARIES WHERE HEATING/CONVERGENCE WILL BECOME MAXIMIZED. MORE LIKELY REGION FOR DIURNAL DEVELOPMENT MAY BE ALONG DRY LINE INTO CENTRAL TX WHERE CLEAR SKIES WILL SUPPORT UNSEASONABLY WARM TEMPERATURES APPROACHING 100F AND ELIMINATE CAP BY 22Z. GIVEN VERY STRONG INSTABILITY AND 40-50 KT EFFECTIVE SHEAR...ANY STORM/S WHICH CAN ERUPT THIS AFTERNOON WILL BECOME SUPERCELLS QUICKLY WITH ENHANCED THREAT OF VERY LARGE HAIL AND ISOLATED TORNADOES. HOWEVER...LACK OF A LOW LEVEL JET OVER THE REGION MAY LIMIT ANY SUSTAINED TORNADO THREAT FOR MUCH OF THE DAY. APPEARS MOST LIKELY SCENARIO FOR WIDESPREAD SEVERE THUNDERSTORMS MAY EVOLVE OUT OF THE HIGH PLAINS AHEAD OF SHORTWAVE TROUGH NOW MOVING INTO THE CENTRAL ROCKIES. BOTH RUC AND GFS INDUCE WEAK PRESSURE FALLS AND SUBSEQUENT VEERING RESPONSE TO THE SURFACE WINDS OVER THE OK/TX PANHANDLES AND FAR SWRN KS. FORECAST SOUNDINGS INDICATE MODEST SURFACE-BASED INSTABILITY BY 00Z ACROSS THIS REGION ALONG WRN EDGE OF H7 THERMAL RIDGE...EVEN BEHIND CURRENT COLD FRONT...WITH 40+ KT EFFECTIVE SHEAR SUPPORTING HIGH-BASED SUPERCELLS. THIS ACTIVITY WILL LIKELY BECOME MORE INTENSE AS IT SPREADS INTO RICHER MOISTURE ACROSS WRN OK/ERN TX PANHANDLE WRAPPING AROUND LOW CENTER ALONG THE RED RIVER. STORMS SHOULD EVOLVE INTO A LARGE COMPLEX WITH VERY LARGE HAIL AND DAMAGING WINDS EWD ACROSS MUCH OF OK THROUGH THE EVENING. SHOULD ERN OK REMAIN CONVECTIVE-FREE...A VERY MOIST AIR MASS WILL SUPPORT EXTREME INSTABILITY THROUGH THE NIGHT INTO WRN AR. GFS DEEPENS A LOW CENTER FROM SOUTH OF ADM BY 03Z AND LIFTS IT NEWD INTO NWRN AR OVERNIGHT WITH SUBSEQUENT INCREASE IN SLY LLJ INTO ERN OK. THIS MAY SUPPORT A WIDESPREAD SEVERE THREAT FROM S-CENTRAL/SERN OK INTO THE OZARK REGION LATER TONIGHT INCLUDING AN INCREASED TORNADO THREAT SHOULD PRESSURE FALLS/CONVERGENCE TAP INTO RICH MARINE AIR. ...LA ACROSS THE CENTRAL GULF COAST STATES... INCREASING SLY LOW LEVEL WINDS ACROSS THE CENTRAL GULF COAST ARE EXPECTED TO LIFT WARM FRONT SLOWLY NWD TODAY AHEAD OF SHORTWAVE TROUGH NOW MOVING ACROSS TX. IN ADDITION...MODELS MAINTAIN 40-50 KT WLY MID LEVEL FLOW ATOP A VERY MOIST BOUNDARY LAYER WITH SURFACE DEW POINTS IN THE LOWER TO MID 70S. THIS SHOULD SUPPORT INCREASE IN CONVECTION THROUGH THE LATE MORNING/AFTERNOON AS HEATING PRODUCES A VERY UNSTABLE AIR MASS. RUC FORECAST SOUNDINGS BECOME VERY FAVORABLE FOR INTENSE SUPERCELLS BY LATE THIS AFTERNOON...THOUGH NAM AND GFS PRODUCE WEAKER H85 WINDS AND LESS SHEAR TODAY. REGARDLESS...EXPECT THREATS FOR SUPERCELLS AND MULTICELL CLUSTERS WILL INCREASE ACROSS THE LOWER MS RIVER VALLEY AND SPREAD/DEVELOP EWD ALONG AND NORTH OF WARM FRONT ACROSS SRN/CENTRAL MS AND SRN/WRN AL TODAY. LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE THREATS...WITH TORNADO POTENTIAL BEING STRONGER SHOULD RUC FORECASTS VERIFY. ..EVANS/JEWELL.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 16:47:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 12:47:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 091645 SWODY1 SPC AC 091643 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1143 AM CDT TUE MAY 09 2006 VALID 091630Z - 101200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS TO THE LOWER MS VALLEY.... ...SRN/CENTRAL MS AND SW AL AREA TODAY... ELEVATED THUNDERSTORMS ARE FORMING THIS MORNING ALONG A NW-SE ORIENTED BAROCLINIC ZONE ACROSS SE MS AND SW AL. LOW-LEVEL WAA...A FEED OF STEEP MID LEVEL LAPSE RATES...AND MUCAPE IN EXCESS OF 2000 J/KG FROM THE SW IS SUPPORTING THIS CONVECTION. THE STORMS MAY GRADUALLY BECOME SURFACE BASED AS THE BOUNDARY LAYER WARMS INTO THE 80S...AND STORM COVERAGE WILL LIKELY INCREASE WITH THE APPROACH OF A MIDLEVEL SHORTWAVE TROUGH MOVING EWD FROM NRN LA TO MS. VERTICAL SHEAR AND INSTABILITY ALONG THE SURFACE BOUNDARY WILL SUPPORT SUPERCELLS WITH A THREAT FOR LARGE HAIL AND DAMAGING WINDS...AND PERHAPS AN ISOLATED TORNADO OR TWO. ...AR/WRN TN/NW MS AREA THIS AFTERNOON... AN MCS CONTINUES TO MOVE ESEWD OVER NRN AR AND SE MO...AND THIS CONVECTION IS ASSOCIATED WITH A WELL-DEVELOPED COLD POOL AND MCV. LOW-LEVEL DESTABILIZATION IN ADVANCE OF THE ONGOING CONVECTION SHOULD ALLOW FOR ADDITIONAL SEVERE STORM DEVELOPMENT THROUGH THE AFTERNOON ALONG THE LEADING EDGE OF THE COLD POOL...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE ACROSS CENTRAL/ERN AR INTO WRN TN AND NW MS THROUGH LATE AFTERNOON. ...CENTRAL/ERN OK AND NE TX THIS AFTERNOON/EVENING... AN OUTFLOW BOUNDARY /TRAILING SWWD FROM THE ONGOING AR STORMS/ IS MOVING SEWD ACROSS SE OK. THIS BOUNDARY WILL LIKELY CONTINUE SEWD ACROSS THE ARKLATEX REGION THIS AFTERNOON...WHILE THE WRN PORTION OF THE OUTFLOW SHOULD STALL ACROSS CENTRAL OK...JUST NE OF A TRIPLE POINT LOW BETWEEN FSI AND OUN. S OF THE LOW...A DRYLINE WILL BECOME BETTER DEFINED ACROSS SRN OK/N TX. THE 12Z SOUNDINGS FROM OUN/FWD SHOW VERY STEEP MID LEVEL LAPSE RATES ABOVE A MOIST BOUNDARY LAYER...AS WELL AS A STRONG CAP WITH CONVECTIVE TEMPERATURES IN THE 90S. WITH LITTLE LARGE SCALE FORCING FOR ASCENT...CONVECTIVE INITIATION WILL RELY ALMOST SOLELY ON THE COMBINED IMPACTS OF DAYTIME HEATING AND MESOSCALE LIFT ALONG THE OUTFLOW AND NEAR THE TRIPLE POINT LOW. IF STORMS CAN FORM...EXTREME INSTABILITY /MLCAPE NEAR 4000 J/KG/ AND MODEST VERTICAL SHEAR WILL SUPPORT A THREAT FOR SUPERCELLS WITH VERY LARGE HAIL...DAMAGING WINDS...AND A COUPLE OF TORNADOES. ...TX PANHANDLE/SW KS/WRN OK OVERNIGHT... A SHORTWAVE TROUGH OVER UT THIS MORNING IS FORECAST TO REACH THE SRN HIGH PLAINS TONIGHT. A MOIST UPSLOPE FLOW REGIME MAY SUPPORT THUNDERSTORM DEVELOPMENT BY LATE EVENING/EARLY TONIGHT OVER THE TX/OK PANHANDLES INTO SW KS...WITH CONVECTION EXPECTED TO GROW INTO A LARGER MCS ACROSS WRN/NWRN OK BY EARLY WEDNESDAY. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THIS ACTIVITY...ESPECIALLY AS THE STORMS ENCOUNTER GREATER INSTABILITY LATE TONIGHT ACROSS OK. ...SE FL THIS AFTERNOON... THE REMNANTS OF OVERNIGHT CONVECTION ARE MOVING SEWD FROM CENTRAL TOWARD SE FL. SOME DAYTIME HEATING PRIOR TO THE ARRIVAL OF ANVIL DEBRIS CLOUDS AND BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S TO NEAR 70 F WILL RESULT IN SUFFICIENT INSTABILITY FOR A FEW STRONG/MARGINALLY SEVERE STORMS THIS AFTERNOON. THE MORE PROBABLE AREAS FOR DEVELOPMENT WILL BE ALONG THE SE MOVING OUTFLOW BOUNDARY...AND WHERE THIS BOUNDARY INTERSECTS THE E COAST SEA BREEZE. ISOLATED DOWNBURST WINDS AND SMALL HAIL WILL BE THE MAIN THREATS. ..THOMPSON/TAYLOR.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 20:10:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 16:10:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 092008 SWODY1 SPC AC 092006 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0306 PM CDT TUE MAY 09 2006 VALID 092000Z - 101200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS OK/TX AND THE LOWER MS VALLEY/TN VALLEY AND PARTS OF THE DEEP SOUTH... ...TN/MS/AL... ARC OF DEEP CONVECTION FROM SWRN KY TO NRN MS CONTINUES EAST TOWARD MIDDLE TN AND TRAILS SWWD OVER NRN MS. AIR MASS IMMEDIATELY AHEAD OF THE LINE HAS BECOME MARGINALLY UNSTABLE WITH DAYTIME HEATING. RADAR SUGGESTS THAT STORM INTENSITY ALONG THE LEADING EDGE OF THE CONVECTIVE LINE HAS CHANGED LITTLE BUT STORM MOTION WAS ONLY ABOUT 25-30KT. THERMODYNAMIC AND KINEMATIC ENVIRONMENT SHOULD CONTINUE TO SUPPORT MARGINALLY SEVERE HAIL/WIND THREAT FOR A COUPLE MORE HOURS BEFORE STORMS ENCOUNTER GREATER STABILITY SITUATED OVER ERN TN. FARTHER SOUTH...BAND OF WEAKLY ORGANIZED STORMS PERSISTS WITHIN SWATH OF LOW LEVEL WARM AIR ADVECTION FROM SRN MS TO ERN AL. THIS ACTIVITY ALSO APPEARS TO BE ENHANCED BY WEAK SRN STREAM IMPULSE DEVELOPING EWD FROM THE LOWER MS VALLEY. SUFFICIENT SPEED AND DIRECTIONAL SHEAR EXIST IN THIS REGION FOR SUPERCELLS WITH ATTENDANT THREAT FOR LARGE HAIL AND POSSIBLY ISOLATED WIND DAMAGE. SEVERE POTENTIAL SHOULD DECREASE AS ACTIVITY SPREADS EAST INTO DRIER MORE STABLE AIR MASS ACROSS ERN AL THIS EVENING. ...ERN OK/AR THIS EVENING THROUGH TONIGHT... SUBSTANTIAL CAP/INHIBITION PERSISTS FROM TX NWD ACROSS THE RED RIVER VALLEY THIS AFTERNOON BASED ON LATEST ANALYSIS AND RAOB FROM DFW. EXPECT THAT THE WARM TEMPERATURES ALOFT...COUPLED WITH LACK OF STRONGER DEEP LAYER ASCENT OVER THE REGION...MAY DELAY ONSET OF SURFACE-BASED TSTM DEVELOPMENT FROM NEAR TRIPLE-POINT LOW AND DRYLINE...EWD ALONG DECAYING OUTFLOW BOUNDARY FROM SERN OK INTO SWRN/SCNTRL AR. HOWEVER...SURFACE TEMPERATURES MAY WARM SUFFICIENTLY NEAR THESE FEATURES TO FOSTER AT LEAST ISOLATED STORM DEVELOPMENT INTO THE EARLY EVENING. STRONGEST SIGNAL FOR CONVECTIVE DEVELOPMENT FROM SHORT-TERM MODEL DATA APPEARS NEAR THE OUTFLOW/WARM FRONT OVER ERN OK/SCNTRL AR THROUGH THIS EVENING. ADDITIONAL DEVELOPMENT APPEARS POSSIBLE NEAR WEAK FRACTURED COLD FRONT OVER SWRN MO/NWRN AR. MORE UNCERTAINTY REGARDING DEVELOPMENT EXISTS SWD ALONG THE DRYLINE WHERE STRONG CAPPING SHOULD PERSIST. ANY ACTIVITY DEVELOPING ACROSS THE REGION WILL OCCUR WITHIN EXTREMELY UNSTABLE AIR MASS. WHILE DEEP LAYER SHEAR REMAINS SOMEWHAT MARGINAL BETWEEN FASTER MID LEVEL FLOW NORTH AND SOUTH...SUFFICIENT LOW LEVEL TURNING NEAR THE BOUNDARIES...IN ADDITION TO POTENTIAL FOR STRONG STRETCHING DUE TO HIGH INSTABILITY...SHOULD PROMOTE SUPERCELL STRUCTURE WITH VERY LARGE HAIL LIKELY. TORNADO AND DAMAGING WIND POTENTIAL WILL ALSO EXIST WITH ANY SUPERCELL TRACKING NEAR/ALONG OUTFLOW/WARM FRONT FEATURE FROM ERN OK INTO WRN AR THIS EVENING. STORM COVERAGE MAY INCREASE ALONG AND NORTH OF THE WARM FRONT OVER ERN OK AND AR THROUGH LATE EVENING AS LOW LEVEL JET DIRECTED INTO THESE AREAS STRENGTHENS. WIND/HAIL AND ISOLATED TORNADO POTENTIAL SHOULD SPREAD GENERALLY EWD/SEWD ACROSS AR...AND PERHAPS INTO NRN LA AND NRN MS THROUGH EARLY WEDNESDAY MORNING. ...SRN HIGH PLAINS TO OK TONIGHT... WATER VAPOR AND LATEST RUC FIELDS CONTINUE TO DEPICT A WELL-DEFINED SHORT WAVE TRACKING EAST ACROSS THE FOUR CORNERS AREA THIS AFTERNOON. THIS FEATURE...COUPLED WITH MOIST POST-FRONTAL UPSLOPE FLOW INTO THE NERN NM/SERN CO HIGH PLAINS...WILL ENHANCE HIGH PLAINS MCS DEVELOPMENT THROUGH THE EVENING. THIS SYSTEM WILL DEVELOP EWD/SEWD INTO INCREASINGLY FAVORABLE ENVIRONMENT FROM THE ERN TX PNHDL EAST ACROSS WRN OK TONIGHT. LOW LEVEL WARM AIR AND MOISTURE ADVECTION...AND DEEP LOW LEVEL ELY INFLOW TO THE NORTH OF RED RIVER TRIPLE-POINT LOW...SHOULD SUSTAIN THE CONVECTIVE COMPLEX. OVERALL PATTERN APPEARS TO SUGGEST A SEVERE MCS WITH DAMAGING WINDS AND HAIL SPREADING EAST INTO CNTRL OK THROUGH EARLY WEDNESDAY MORNING. ..CARBIN.. 05/09/2006  From swody1 at goshenarc.org Wed May 10 01:13:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 21:13:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100109 SWODY1 SPC AC 100107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT TUE MAY 09 2006 VALID 100100Z - 101200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS SERN OK...WRN AND INTO CENTRAL AR...AND NERN TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS AND INTO THE CENTRAL GULF COAST REGION... ...SRN PLAINS... TWO SEPARATE CLUSTERS OF SEVERE/SUPERCELL STORMS ARE ONGOING ATTM...ONE ACROSS ERN PORTIONS OF THE TX PANHANDLE AHEAD OF UPPER TROUGH AND THE OTHER OVER SERN OK AND NNEWD INTO SRN MO/NRN AR ALONG COLD FRONT. VERY UNSTABLE AIRMASS IS IN PLACE ACROSS SERN OK AND ADJACENT N CENTRAL AND NERN TX/WRN AR...WHERE 4000 TO 5000 J/KG MEAN-LAYER CAPE IS INDICATED. WITH 40 TO 45 KT WLY MID-LEVEL FLOW ABOVE INCREASING/VEERING LOW-LEVEL WINDS...SHEAR IS SUPPORTIVE OF SUPERCELLS -- AND ATTENDANT THREAT FOR VERY LARGE HAIL AND DAMAGING WINDS ALONG WITH ISOLATED TORNADOES. EXPECT STORMS TO INCREASE AS LOW-LEVEL JET DEVELOPS...AND WILL SPREAD EWD/SEWD ACROSS AR/NERN TX AND LIKELY INTO PARTS OF LA/MS BY THE END OF THE PERIOD -- ACCOMPANIED BY A CONTINUED THREAT FOR SEVERE WEATHER. MEANWHILE...EXPECT STORMS OVER THE TX PANHANDLE TO CONTINUE SPREADING EWD INTO WRN OK/N TX OVER THE NEXT SEVERAL HOURS. THOUGH STORMS ARE MAINLY N OF THE COLD FRONT...SUFFICIENT HEATING N OF BOUNDARY HAS RESULTED IN SURFACE-BASED CAPE 1500 TO 3000 J/KG. WITH SUFFICIENTLY STRONG/FAVORABLY-VEERING DEEP-LAYER WIND FIELD...EXPECT THREAT FOR LARGE HAIL AND LOCALLY-DAMAGING WINDS ALONG WITH AN ISOLATED TORNADO TO CONTINUE AS STORMS ENCOUNTER MORE STABLE AIR WITH EWD EXTENT. STORMS WILL LIKELY ROLL THROUGH THE OVERNIGHT HOURS...ALONG WITH A CONTINUED SEVERE THREAT. ...CENTRAL GULF COAST REGION... THUNDERSTORMS HAVE WEAKENED ACROSS NRN AL AS THEY HAVE ENCOUNTERED MUCH MORE STABLE AIRMASS. HOWEVER...STRONG/SEVERE STORMS CONTINUE OVER SERN MS/SRN AL WHERE MOIST/MODERATELY-UNSTABLE BOUNDARY LAYER REMAINS. EVENING LIX /SLIDELL LA/ RAOB INDICATES DEEP-LAYER WIND PROFILE SUPPORTIVE OF SEVERE STORMS...WHICH COMBINED WITH FAVORABLE AIRMASS SUGGESTS THAT THREAT FOR HAIL AND LOCALLY DAMAGING WINDS WILL PERSIST/SPREAD SEWD INTO THE FL PANHANDLE OVER THE NEXT SEVERAL HOURS. ...MID/UPPER MS VALLEY... LIMITED/LINGERING SEVERE THREAT SHOULD WANE THROUGH THIS EVENING AS BOUNDARY LAYER SLOWLY STABILIZES. A FEW STRONGER STORMS MAY STILL PRODUCE BRIEF GUSTY WINDS OR MARGINAL HAIL FOR THE NEXT COUPLE OF HOURS. ..GOSS.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 06:11:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 02:11:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100608 SWODY1 SPC AC 100607 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0107 AM CDT WED MAY 10 2006 VALID 101200Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS WRN KY...WRN AND MIDDLE TN...ERN AR...NERN LA...MUCH OF MS...AND NRN AND WRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDWEST STATES SWD ACROSS THE OH/TN /MS VALLEYS TO THE GULF COAST... ...SYNOPSIS... MID-LEVEL SHORT-WAVE TROUGH MOVING ACROSS KS/OK/TX AT THE START OF THE PERIOD WILL MOVE RAPIDLY EWD ACROSS MO/AR THROUGH THE DAY. THIS FEATURE WILL EVENTUALLY BECOME ABSORBED BY LARGER TROUGH DIGGING SWD INTO THE PLAINS. BY THE END OF THE PERIOD...A LARGE CLOSED LOW IS FORECAST ACROSS THE MID MS/LOWER OH VALLEY REGION -- WITHIN LARGE TROUGH COVERING THE ENTIRE CENTRAL CONUS. AT THE SURFACE...COLD FRONT IS INITIALLY FORECAST TO EXTEND FROM ERN WI SWD ACROSS IL...AND THEN SWWD ACROSS SERN MO/NWRN AR AND INTO NRN AND WRN TX. A LOW FORECAST ALONG THIS FRONT OVER NERN TX AT THE START OF THE PERIOD SHOULD DEEPEN AND MOVE NEWD TO THE MID MS/LOWER OH VALLEY BY LATE AFTERNOON/EARLY EVENING...WITH THE COLD FRONT EXTENDING SWWD ACROSS WRN TN/NWRN MS/LA AND INTO THE TX COASTAL REGION. OVERNIGHT...THIS LOW SHOULD DEEPEN RAPIDLY AND MOVE NWD INTO NRN INDIANA/LOWER MI BY THE END OF THE PERIOD...WITH COLD FRONT ARCING SEWD ACROSS OH...SWD ALONG THE SRN APPALACHIANS...AND THEN SWWD INTO THE CENTRAL GULF OF MEXICO. ...ERN TX EWD ACROSS THE MS/OH/TN VALLEYS AND GULF COAST REGION... VERY COMPLEX BUT POTENTIALLY SIGNIFICANT SEVERE WEATHER EVENT IS ANTICIPATED THIS PERIOD...WITH WIDESPREAD ONGOING CONVECTION ACROSS MUCH OF THE RISK AREA COMPLICATING THE SCENARIO. DEGREE OF DESTABILIZATION OVER THE NRN HALF OF THE OUTLOOK AREA -- I.E. ACROSS THE TN AND OH VALLEY REGION -- IS DIFFICULT TO DISCERN AS A RESULT OF THE ONGOING CLOUDS/PRECIPITATION. FROM A LARGE-SCALE PERSPECTIVE...A STRENGTHENING MID-LEVEL TROUGH -- ACCOMPANIED BY A STRONG /70 TO 90 KT/ MID-LEVEL JET STREAK -- WILL SPREAD EWD ALONG WITH INTENSIFYING ATTENDANT COLD FRONT. WARM SECTOR AIRMASS FEATURING LOW TO MID 60S DEWPOINTS N OF THE TN VALLEY AND LOW TO MID 70S ACROSS THE GULF COAST STATES WILL BE IN PLACE AHEAD OF COLD FRONT -- THOUGH AGAIN...THE DEGREE OF DESTABILIZATION FROM THE MID MS/TN VALLEYS NWD REMAINS IN QUESTION. NONETHELESS...STRENGTH OF UPPER SYSTEM AND ASSOCIATED WIND FIELD SPREADING ACROSS MOIST BOUNDARY LAYER SUGGESTS THE POTENTIAL FOR A WIDESPREAD SIGNIFICIANT SEVERE WEATHER EPISODE. AS FRONT MOVES EWD...EXPECT STORMS TO CONTINUE/SPREAD EWD THROUGH THE AFTERNOON ACROSS THE MID MS/TN VALLEYS. NEW STORM DEVELOPMENT SHOULD OCCUR SWD ALONG FRONT ACROSS LA AND INTO ERN/SERN TX. STRONG WIND FIELD WILL YIELD SHEAR FAVORABLE FOR SEVERE/SUPERCELL STORMS...WITH STORMS EXPECTED TO RAPIDLY BECOME SEVERE. FURTHER N...ONGOING CONVECTION SHOULD INTENSIFY AS UPPER SYSTEM AND ASSOCIATED SURFACE FRONT STRENGTHEN. STORMS SHOULD ALSO DEVELOP NWD ALONG FRONT ACROSS IL INTO THE GREAT LAKES REGION...THOUGH LESS UNSTABLE AIRMASS AND SOMEWHAT WEAKER WIND FIELD SUGGESTS A LESS SIGNIFICANT SEVERE THREAT. GIVEN DEGREE OF INSTABILITY EXPECTED ACROSS SRN PORTIONS OF THE OUTLOOK -- ...EXPECT VERY LARGE HAIL TO BE THE MAIN SEVERE THREAT...ALONG WITH DAMAGING WINDS AND ISOLATED TORNADOES. GREATEST TORNADO THREAT -- INCLUDING THE POTENTIAL FOR A COUPLE STRONG/DAMAGING TORNADOES -- APPEARS TO EXIST ACROSS THE NRN HALF OF MS AND INTO WRN AND MIDDLE TN. DEPENDING UPON DEGREE OF HEATING/DESTABILIZATION WHICH CAN OCCUR NWD INTO THE OH VALLEY...THREAT MAY EXTEND FURTHER N THAN CURRENTLY ANTICIPATED. STORMS WILL CONTINUE EWD OVERNIGHT...CROSSING THE OH/TN VALLEYS AND MOVING INTO THE APPALACHIANS. ATTM...IT APPEARS THAT SEVERE THREAT SHOULD DIMINISH WITH TIME DURING THE OVERNIGHT HOURS...AND SHOULD NOT EXTEND E OF THE MOUNTAINS. HOWEVER...LIMITED THREAT MAY SPREAD EWD ACROSS GA...AND POSSIBLY INTO SC BY THE END OF THE PERIOD. ..GOSS.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 12:34:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 08:34:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101231 SWODY1 SPC AC 101230 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0730 AM CDT WED MAY 10 2006 VALID 101300Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS FROM LA/MS INTO SWRN KY... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM THE UPPER TX COAST INTO THE OH VALLEY... ...TORNADOES...A FEW STRONG ARE POSSIBLE ACROSS PORTIONS OF THE GULF STATES INTO THE TN VALLEY... A SIGNIFICANT SEVERE WEATHER EVENT IS EXPECTED TO EVOLVE ACROSS THE LOWER MS VALLEY AND CNTRL GULF STATES...NWD ACROSS PORTIONS OF THE TN VALLEY TODAY. TORNADOES...POTENTIALLY STRONG...DAMAGING WINDS AND VERY LARGE HAIL ARE ALSO POSSIBLE PRIOR TO COLD FRONTAL PASSAGE. THREE MCS CLUSTERS ARE ONGOING EARLY THIS MORNING FROM THE RED RIVER REGION OF SRN OK/NCNTRL TX...EAST ACROSS AR...AND ANOTHER INTO CNTRL AL. THIS EARLY ACTIVITY WILL PLAY AN IMPORTANT ROLE IN FUTURE DEVELOPMENT/STORM MODE AS BOUNDARY LAYER WARMS TO THE SOUTH OF CONVECTIVE OUTFLOWS. OVERNIGHT TRENDS REMAIN SUPPORTIVE OF EARLIER OUTLOOK...ALTHOUGH CONFIDENCE IN TORNADIC SUPERCELLS HAS RISEN ACROSS MS INTO NRN AL. THIS ZONE OF HEIGHTENED INTEREST IS PARTIALLY DUE TO THE INFLUENCE OF OVERNIGHT MCS THAT HAS BACKED LOW LEVEL FLOW TO THE NORTH OF ASSOCIATED OUTFLOW BOUNDARY. THIS WILL MAINTAIN HIGH HELICITY ENVIRONMENT WITHIN STRONGEST ZONE OF LOW LEVEL WARM ADVECTION WHERE SUPERCELL THUNDERSTORM DEVELOPMENT IS EXPECTED BY EARLY AFTERNOON. THERE IS SOME CONCERN THAT AFOREMENTIONED MCS CLUSTERS COULD HINDER DISCRETE DEVELOPMENT ACROSS FAR NRN PORTIONS OF MODERATE RISK...HOWEVER SIGNIFICANT CAP ACROSS SERN TX/LA WILL PREVENT SWD DEVELOPMENT THROUGH MID-LATE MORNING. AS A RESULT...VERY UNSTABLE AIR MASS WILL SPREAD NEWD...RETURNING ATOP STRONGLY SHEARED BUT LESS CAPPED REGION OF THE NCNTRL GULF STATES. CURRENT THINKING IS STRONGEST FORCED CONVECTION ALONG COLD FRONT WILL MAINTAIN N-S LINEAR STRUCTURE AS IT ADVANCES EWD ALONG THE RED RIVER OF SRN OK/NERN TX. THIS ACTIVITY SHOULD GRADUALLY EXPAND IN AREAL COVERAGE...POSSIBLY OVERTAKING DOWNSTREAM CONVECTION OVER AR BY MID-LATE MORNING. AN EVER EXPANDING MCS MAY EVOLVE FROM THIS INTERACTION WITH NEWD DEVELOPMENT INTO THE WRN PORTIONS OF THE TN VALLEY AS SFC LOW LIFTS NEWD. DOWNSTREAM...BOUNDARY LAYER HEATING/MOISTENING ATOP MODIFYING OUTFLOW AIR MASS OVER MS/AL SHOULD ALLOW FOR MORE DISCRETE SUPERCELL STRUCTURES TO DEVELOP. FORECAST SOUNDINGS FOR THIS REGION...PARTICULARLY FROM THE 09Z RUC...STRONGLY FAVOR TORNADIC DEVELOPMENT AS CELL MOTION UTILIZES HIGHER HELICITY ENVIRONMENT. OTHER STORMS WILL ALSO DEVELOP ACROSS THE WARM SECTOR AHEAD OF THE COLD FRONT AS IT ADVANCES EWD INTO LA. VERY STEEP LAPSE RATES AND EXTREME SBCAPE...IN EXCESS OF 5000 J/KG...WILL AID IN VERY LARGE HAIL DEVELOPMENT...AS WELL AS ENHANCE DAMAGING WIND POTENTIAL. MULTIPLE STORM MODES APPEAR LIKELY ACROSS THE MODERATE RISK REGION...WITH WIDESPREAD SEVERE CONSISTING OF TORNADOES...DAMAGING HAIL...AND INTENSE WIND. FRONTAL PASSAGE LATE TONIGHT WILL END SEVERE THREAT FROM WEST TO EAST. ..DARROW/LEVIT.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 16:36:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 12:36:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101634 SWODY1 SPC AC 101632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT WED MAY 10 2006 VALID 101630Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF EXTREME SERN AR...NERN LA...CENTRAL AND SRN MS...CENTRAL AND SRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GULF COASTAL STATES NWD ACROSS THE MS/TN AND OH VALLEY REGION... ...TORNADOES...A FEW STRONG..ARE POSSIBLE ACROSS PORTIONS OF THE CENTRAL GULF STATES THIS AFTERNOON AND EVENING ACROSS THE SOUTH CENTRAL GULF COAST STATES... UPPER TROUGH OVER THE CENTRAL PLAINS WILL DEEPEN AND SHIFT EWD INTO MID MS/OH VALLEYS TONIGHT. A COLD FRONT WILL SWEEP RAPIDLY THROUGH THE MS VALLEY REGION TODAY AND INTO THE OH/TN VALLEYS AND CENTRAL GULF REGION TONIGHT. A WEAK LOW ALONG THE FRONT IS FORECAST TO DEEPEN OVER THE OHIO VALLEY TONIGHT. LOWER/MID MS VALLEY EWD THROUGH THE CENTRAL GULF COASTAL STATES AND TN VALLEY... THREE MCS CLUSTERS WERE LOCATED FROM AL TO AR THIS MORNING. THE LEADING CLUSTER WAS WEAKENING IN SRN AL...THE SECOND ONE WAS MOVING THROUGH NRN MS INTO NWRN AL...AND THE THIRD AND MOST INTENSE CLUSTER WAS MOVING THROUGH SRN/CENTRAL AR. A BOUNDARY... SEPARATING RAIN COOLED AIR TO THE NORTH AND A WARM SECTOR TO THE SOUTH WITH MLCAPES IN EXCESS OF 3000 J/KG...EXTENDED FROM SERN AR ESEWD ACROSS CENTRAL MS INTO SWRN AL. ALTHOUGH THE AIR MASS ACROSS THE WARM SECTOR IS CURRENTLY CAPPED...STRONG FORCING AND 50-60 KT DEEP LAYER SHEAR HAS RESULTED IN INTENSE STORMS/SUPERCELLS WITHIN THE AR THUNDERSTORM LINE. WITH ADDITIONAL HEATING AND INCREASING LARGE SCALE LIFT...IN RESPONSE TO SHORTWAVE TROUGH MOVING EWD OUT OF OK...STORMS ARE LIKELY TO BECOME ROOTED IN THE BOUNDARY LAYER AND TAP INTO THE STRONG INSTABILITY. THE DEGREE OF INSTABILITY... DEEP LAYER SHEAR AND 30-40 KT 1 KM SHEAR...WILL FAVOR INTENSE SUPERCELLS WITH THE POTENTIAL FOR VERY DAMAGING WINDS...LARGE HAIL AND STRONG TORNADOES ACROSS THE MODERATE RISK AREA THIS AFTERNOON/EVENING. THE MORNING MCS CLUSTERS RESULTED IN EXTENSIVE CLOUDS AND A RAIN COOLED BOUNDARY LAYER SURROUNDING THE TN VALLEY. THIS WILL LIMIT THE NWD EXTENT OF THE STRONGER INSTABILITY ACROSS PORTIONS OF NRN MS/AL NWD INTO SRN KY. THOUGH SCATTERED SEVERE STORMS ARE EXPECTED TO DEVELOP ACROSS THESE AREAS THIS AFTERNOON AS THE UPPER TROUGH AND ASSOCIATED COLD FRONT APPROACHES FROM THE WEST...THE COOL BOUNDARY LAYER SHOULD RESULT IN MOSTLY ELEVATED STORMS WITH MAINLY A SEVERE HAIL AND WIND THREAT. ...OH VALLEY... A LARGE CLOUD SHIELD AND SOME PRECIPITATION WILL SPREAD NWD ACROSS THE REGION THROUGHOUT THE AFTERNOON AND INHIBIT STRONG STORM DEVELOPMENT THROUGH MOST OF THE DAY. HOWEVER...AS THE UPPER TROUGH APPROACHES ALONG WITH A 70 KT MID LEVEL WIND MAX...SURFACE LOW IS FORECAST TO MOVE FROM SRN INDIANA NWD INTO WRN OH AND DEEPEN. ALTHOUGH INSTABILITY WILL BE WEAK DUE TO DEEP MOIST VERTICAL PROFILES...BACKING BOUNDARY LAYER WINDS AND STRENGTHENING WINDS ALOFT WILL BECOME MORE FAVORABLE FOR SUPERCELLS AND TORNADOES. THE BIGGEST CONCERN ABOUT A HIGHER RISK ATTM IS THE CURRENT FORECAST OF POOR LAPSE RATES. HOWEVER...THE WIND PROFILES AND PRESSURE FALLS MAY SUPPORT A TORNADO TREAT ACROSS PORTIONS OF INDIANA AND OH OVERNIGHT. ...SERN MO AND SRN IL... AS ONE SHORTWAVE TROUGH LIFTS NEWD ACROSS THE REGION THIS AFTERNOON...SOME HEATING MAY AID IN THE DEVELOPMENT OF STRONGER STORMS ALONG AND AHEAD OF THE COLD FRONT. THE BOUNDARY LAYER SHOULD REMAIN RELATIVELY COOL...BUT 30-40 KT DEEP LAYER SHEAR AND MLCAPES UP TO 1000 J/KG WILL SUPPORT SOME STORMS WITH SEVERE HAIL/WIND. ..IMY.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 20:08:15 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 16:08:15 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 102003 SWODY1 SPC AC 102001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT WED MAY 10 2006 VALID 102000Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER MS VALLEY FROM NERN LA...OVER SCNTRL MS AND SWRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE TX GULF COAST ACROSS THE LOWER OH VALLEY TO LOWER MI... ...SYNOPSIS... COMPLEX AND POTENTIALLY VOLATILE SEVERE WEATHER SITUATION NOW UNFOLDING ACROSS THE LOWER MS VALLEY AND DEEP SOUTH. ADDITIONALLY...SEVERE STORM POTENTIAL IS EXPECTED TO INCREASE ACROSS PARTS OF THE LOWER OH VALLEY AND MIDWEST FROM LATE THIS AFTERNOON INTO THE EVENING. STRONG DYNAMIC FORCING ASSOCIATED WITH A POTENT SHORT WAVE TROUGH AND 70KT MID LEVEL WIND MAX WILL CONTINUE TO OVERSPREAD VERY UNSTABLE AIR MASS ACROSS PARTS OF LA...MS...AL...AND THE FL PANHANDLE OVER THE NEXT FEW HOURS. AS THE MID/UPPER LEVEL SYSTEM SWINGS EWD/NEWD ACROSS THESE AREAS...RAPID SURFACE CYCLOGENESIS WILL OCCUR ALONG A STRENGTHENING FRONTAL ZONE SITUATED FROM LAKE MI SWD TO THE CONFLUENCE OF THE OH/MS RIVERS. THE SURFACE LOW WILL DEEPEN RAPIDLY TONIGHT WHILE TRACKING INTO SRN LOWER MI. THE COLD FRONT ASSOCIATED WITH THIS CYCLONE WILL ACCELERATE ESEWD ACROSS THE MID/LOWER MS VALLEY THROUGH LATE THIS EVENING. ...LA...SRN MS/AL...WRN FL PNHDL... OUTFLOW FROM A PAIR OF MATURE MESOSCALE CONVECTIVE SYSTEMS CROSSING NRN MS/AL HAS STRONGLY REINFORCED FRONTAL ZONE/WARM FRONT SITUATED FROM NERN LA EWD TO SWRN AL. MEANWHILE...COLD FRONT WAS ADVANCING EAST AND INTERSECTS THE WRN EXTENSION OF THE WARM FRONT ACROSS NRN LA. AIR MASS AHEAD OF AND ALONG THESE BOUNDARIES HAS BECOME EXTREMELY UNSTABLE WITH LATEST DIAGNOSTIC DATA INDICATING MLCAPE AROUND 3000 J/KG. MESOSCALE FORCING/ASCENT NEAR THE FRONTS...IN COMBINATION WITH DIURNAL HEATING...WILL CONTINUE TO PROMOTE SURFACE-BASED TSTM DEVELOP ACROSS THE WARM SECTOR THROUGH THIS EVENING. THIS ACTIVITY WILL OCCUR ALONG THE SRN EDGE OF THE FASTER MID LEVEL TROPOSPHERIC FLOW...AND WITHIN A KINEMATIC ENVIRONMENT CHARACTERIZED BY PRIMARILY UNIDIRECTIONAL SHEAR SUPPORTIVE OF SUPERCELLS. IN ADDITION TO VERY LARGE HAIL AND HIGH WINDS WITH THIS CONVECTION...A FEW TORNADOES WILL ALSO BE POSSIBLE...ESPECIALLY FROM DISCRETE CELLS TRACKING NEAR/ALONG THE OUTFLOW-REINFORCED BOUNDARY FROM ERN LA ACROSS SCNTRL MS AND INTO SWRN AL OVER THE NEXT SEVERAL HOURS. ...TX GULF COAST... COLD FRONT WILL CONTINUE TO DEVELOP SEWD INTO STRONG TO EXTREME INSTABILITY ALONG THE TX COAST FROM BRO THROUGH HOU. ALTHOUGH LACK OF STRONGER LARGE SCALE FORCING AND STRONG CAP MAY INHIBIT CONVECTIVE DEVELOPMENT WITH SWD/SWWD EXTENT ALONG THE FRONT... LATEST SHORT-TERM GUIDANCE INDICATES AT LEAST SCATTERED STRONG TO SEVERE STORM DEVELOPMENT COULD OCCUR AS THE BOUNDARY MOVES ACROSS THE COASTAL PLAIN...AND EVEN INTO DEEP SOUTH TX...THROUGH THE EVENING. VERY LARGE HAIL...WIND DAMAGE...AND A COUPLE OF TORNADOES APPEAR POSSIBLE WITH THIS ACTIVITY GIVEN MORE THAN ADEQUATE DEEP LAYER SHEAR FOR UPDRAFT ROTATION/ORGANIZATION. ...NERN AR/SERN MO NEWD ACROSS THE MIDWEST TO LOWER MI... VERY COMPLICATED FORECAST SCENARIO ACROSS THESE AREAS THROUGH THIS EVENING. AIR MASS DESTABILIZATION HAS BEEN STRONGLY HINDERED BY THE PASSAGE OF A SERIES OF STORM COMPLEXES FARTHER SOUTH AND EAST. WEAK AIR MASS RECOVERY WAS NOW UNDERWAY ACROSS AR/SERN MO AND GRADUAL DESTABILIZATION MAY OCCUR COINCIDENT WITH CYCLOGENESIS OVER THE LOWER OH VALLEY THROUGH LATE AFTERNOON. ANOTHER POCKET OF WEAK INSTABILITY EXISTS ACROSS NRN IL/IND AND INTO LOWER MI WHERE MARGINAL HEATING HAS CONTRIBUTED TO WEAKLY CAPPED MLCAPE AROUND 500 J/KG. TSTMS WERE DEVELOPING ACROSS THESE AREAS AS STRENGTHENING LARGE SCALE FORCING FOR ASCENT BEGINS TO ACT ON THE MARGINALLY UNSTABLE AIR MASS. STRONG DYNAMICS ASSOCIATED WITH RAPID HEIGHT FALLS AND INTENSIFYING MID LEVEL WINDS WILL LIKELY RESULT IN AN INCREASINGLY FAVORABLE ENVIRONMENT FOR ROTATING STORMS THROUGH THIS EVENING. ENHANCED LOW LEVEL SHEAR AND HIGH BOUNDARY LAYER RH NEAR THE DEEPENING SURFACE LOW COULD LEAD TO AN INCREASING POSSIBILITY OF TORNADOES IF SUFFICIENT INSTABILITY CAN DEVELOP TO MAINTAIN MODEST TO STRONG STORM UPDRAFTS. AREAS FROM THE LOWER OH RIVER VALLEY... NWD INTO LOWER MI...WILL NEED TO BE MONITORED CLOSELY FOR STORM EVOLUTION THROUGH THE EVENING. CURRENTLY...LIMITED INSTABILITY AND UNCERTAINTIES REGARDING AIR MASS RECOVERY SUGGEST MAINTAINING RELATIVELY LOW SEVERE WEATHER/TORNADO PROBABILITIES OVER THE REGION. ..CARBIN.. 05/10/2006  From swody1 at goshenarc.org Fri May 12 00:34:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 11 May 2006 20:34:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 120031 SWODY1 SPC AC 120029 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 PM CDT THU MAY 11 2006 VALID 120100Z - 121200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN NC THROUGH EARN PARTS OF THE MID ATLANTIC AREA... ...ERN NC THROUGH ERN VA...MD AND SERN PA... EARLY THIS EVENING A COLD FRONT EXTENDS FROM SERN GA NWD THROUGH CNTRL NC TO A SURFACE LOW IN N CNTRL VA. THIS BOUNDARY THEN EXTENDS NWWD AS AN OCCLUDED FRONT THROUGH PA AND NWWD INTO THE GREAT LAKES. THE PRE-FRONTAL WARM SECTOR IS ONLY MARGINALLY UNSTABLE WITH MLCAPE FROM 500 TO 1000 J/KG OWING TO WIDESPREAD CLOUDS AND MODEST LAPSE RATES. THIS CONTINUES TO BE THE MAIN LIMITING FACTOR FOR A MORE ROBUST SEVERE THREAT. BAND OF PRE-FRONTAL STORMS EXTENDS FROM NERN NC THROUGH ERN VA...N CNTRL MD AND INTO SERN PA. A 40+ KT LOW LEVEL JET EXISTS OVER ERN VA INTO ERN PA WITHIN ZONE OF LARGE SCALE ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH EJECTING NEWD THROUGH THE MID ATLANTIC. THE STRONG LOW LEVEL JET AND MID-UPPER LEVEL WIND FIELDS ACCOMPANYING THE SHORTWAVE TROUGH ARE RESULTING IN FAVORABLE SHEAR PROFILES FOR A FEW EMBEDDED SUPERCELLS WITHIN THE CONVECTIVE BAND. THREATS FOR ISOLATED TORNADOES AS WELL AS DAMAGING WIND ARE EXPECTED TO PERSIST INTO THE MID EVENING FROM EXTREME ERN VA INTO MD AND POSSIBLY DEL AS ACTIVITY SHIFTS EWD. THREAT SHOULD DIMINISH LATER THIS EVENING AS BOUNDARY LAYER COOLS AND AS ONGOING ACTIVITY MOVES OFFSHORE. THE STRONGER LOW LEVEL JET WILL GRADUALLY SHIFT NWD INTO THE NERN STATES AWAY FROM THE WARM SECTOR. LIMITED INSTABILITY IN THIS REGION SHOULD PRECLUDE ANY ADDITIONAL SEVERE THREAT. ..DIAL.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 05:17:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 01:17:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 120514 SWODY1 SPC AC 120512 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1212 AM CDT FRI MAY 12 2006 VALID 121200Z - 131200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THIS PERIOD WITH A LARGE UPPER LOW CENTERED OVER THE GREAT LAKES REGION ALONG WITH SHORTWAVE RIDGING OVER THE ROCKIES. A SERIES OF SHORTWAVE TROUGHS WILL MOVE ALONG THE NWRN PERIPHERY OF THE UPPER RIDGE AND THROUGH THE PACIFIC NW. ...MID ATLANTIC THROUGH NERN STATES... A SERIES OF VORTICITY MAXIMA ROTATING THROUGH UPPER LOW AND STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH COLD AIR ALOFT WILL MAINTAIN A THREAT FOR ISOLATED THUNDERSTORMS FROM PARTS OF VA NWD INTO THE MID ATLANTIC. THUNDERSTORMS WILL BE MOST LIKELY DURING AFTERNOON AS HEATING DESTABILIZES THE BOUNDARY LAYER. LIMITED INSTABILITY AND LOW LEVEL MOISTURE SUGGEST LIGHTNING ACTIVITY SHOULD REMAIN ISOLATED AND WILL DIMINISH WITH LOSS OF HEATING. ...LOWER MS VALLEY AREA... SWLY LOW LEVEL JET WILL STRENGTHEN OVERNIGHT INTO THE LOWER MS VALLEY AS SURFACE RIDGE AXIS SHIFTS EWD. LIMITED BOUNDARY LAYER MOISTURE WILL EXIST ABOVE A PLUME OF STEEP MID LEVEL LAPSE RATES...RESULTING IN MUCAPE GENERALLY BELOW 500 J/KG. A FEW STORMS MAY DEVELOP WITHIN THE WARM ADVECTION REGIME FRIDAY NIGHT...BUT EXPECTED WEAK INSTABILITY WILL LIMIT ANY POTENTIAL SEVERE THREAT. ...SRN FL... A FEW STORMS WILL REMAIN POSSIBLE ALONG AND S OF COLD FRONT INTO THE EARLY AFTERNOON ACROSS PARTS OF SRN FL. AN ISOLATED STORM OR TWO COULD PRODUCE STRONG GUSTY WINDS. WEAK MID LEVEL LAPSE RATES AND MODEST VERTICAL SHEAR SUGGEST OVERALL SEVERE POTENTIAL WILL REMAIN LIMITED. ...MT... A COLD FRONT WILL MOVE EWD THROUGH MT DURING THE DAY AS A SHORTWAVE TROUGH ADVANCES EWD THROUGH SWRN CANADA. VERY MARGINAL INSTABILITY WILL BE POSSIBLE IN ADVANCE OF EWD MOVING COLD FRONT. A FEW HIGH BASED STORMS MAY DEVELOP BY LATE AFTERNOON INTO THE EARLY EVENING OVER THE HIGHER TERRAIN OF MT AS WELL AS ALONG AND AHEAD OF EWD ADVANCING COLD FRONT. ACTIVITY SHOULD DIMINISH BY EARLY EVENING AS THE BOUNDARY LAYER COOLS. ..DIAL/BRIGHT.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 12:49:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 08:49:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121246 SWODY1 SPC AC 121244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT FRI MAY 12 2006 VALID 121300Z - 131200Z ...NO SVR TSTM AREAS FORECAST... LARGE CLOSED UPPER LOW OVER THE GREAT LAKES REGION WILL MAINTAIN RELATIVELY DRY/STABLE CONDITIONS ACROSS THE PLAINS AND GULF COAST STATES TODAY. A FEW SMALL REGIONS WILL MAINTAIN A RISK OF THUNDERSTORMS TODAY...BUT WEAK CAPE VALUES WILL LIMIT THE POTENTIAL OF SEVERE STORMS. ...SOUTH FL... SURFACE COLD FRONT IS SAGGING SOUTHWARD ACROSS THE FL PENINSULA TODAY...WITH A LINE OF SCATTERED THUNDERSTORMS CURRENTLY OVER SOUTH FL. THIS ACTIVITY IS EXPECTED TO CONTINUE TRACKING SOUTHWARD AND OFFSHORE BY MIDDAY. VERTICAL SHEAR PROFILES ARE FAVORABLE FOR ORGANIZED/SEVERE STORMS...BUT WEAK CAPE AND UNFAVORABLE TIMING SUGGEST THREAT DOES NOT WARRANT SEVERE PROBABILITIES. ...NY... RELATIVELY COLD TEMPERATURES ALOFT ARE EXPECTED TODAY ACROSS PARTS OF NY AND SOUTHERN NEW ENGLAND. FORECAST SOUNDINGS AND VISIBLE SATELLITE TRENDS IN THIS AREA SUGGEST SUBSTANTIAL DAYTIME HEATING WILL OCCUR THIS AFTERNOON. HOWEVER...LIMITED MOISTURE CONTENT OF AIR MASS SHOULD PRECLUDE THE DEVELOPMENT OF STRONG/SEVERE STORMS. ...MT... MORNING WATER VAPOR IMAGERY SHOWS SHORTWAVE TROUGH OVER WESTERN MT. THIS FEATURE WILL TRACK EASTWARD INTO THE ADJACENT HIGH PLAINS THIS AFTERNOON AND EVENING. STEEP LAPSE RATES AND MARGINAL INSTABILITY ARE EXPECTED TO DEVELOP OVER CENTRAL MT. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BY LATE AFTERNOON AND EARLY EVENING. NO SEVERE STORMS ARE FORECAST AT THIS TIME. ...OK/AR/MS.. MODELS TAKE SHORTWAVE TROUGH NOW OVER NM/WEST TX EASTWARD AND DE-AMPLIFY IT OVER TX THIS EVENING. MEANWHILE...WESTERLY/NORTHERLY SURFACE WINDS WILL PERSIST IN THIS REGION. LITTLE IN THE WAY OF LOW LEVEL MOISTENING IS EXPECTED...LIMITING DESTABILIZATION AND OVERALL SEVERE THREAT. ISOLATED THUNDERSTORMS ARE POSSIBLE AFTER DARK IN THIS AREA...BUT THREAT OF SEVERE STORMS IS RATHER LOW. ..HART.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 16:20:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 12:20:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121610 SWODY1 SPC AC 121608 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1108 AM CDT FRI MAY 12 2006 VALID 121630Z - 131200Z ...NO SVR TSTM AREAS FORECAST... LARGE AND UNSEASONABLY COOL SURFACE AND UPPER AIR CYCLONE WESTERN GREAT LAKES CONTINUES TO DOMINATE THE EASTERN TWO-THIRDS OF THE CONUS. COLD FRONT CURRENTLY PASSING THRU S FL WITH A RELATIVELY STABLE AIR MASS IN ITS WAKE OVER MUCH OF THE COUNTRY E OF ROCKIES. A WEAK TROUGH IN THE WSWLY FLOW ACROSS PAC NW AND NRN ROCKIES WILL PROVIDE SOME SUPPORT FOR HIGH BASED CONVECTION THIS AFTERNOON AND EVENING NRN ROCKIES. WHILE MOISTURE IS LIMITED THE STEEP LAPSE RATES IN PLACE AND STRONG HEATING WILL BE SUFFICIENT FOR A FEW THUNDERSTORMS ACROSS CENTRAL/ERN MT. AS PRESSURES FALL SRN HIGH PLAINS AND LOW LEVEL FLOW BACKS TO SLY ACROSS TX...SOME LOW LEVEL MOISTURE WILL BEGIN RETURNING...PARTICULARLY TONIGHT. WARM ADVECTION IN CONJUNCTION WITH EXPECTED STEEP LAPSE RATES COULD LEAD TO A FEW THUNDERSTORMS DEVELOPING MAINLY AFTER 06Z PARTS OF THE LOWER MS VALLEY. ..HALES/GRAMS.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 19:58:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 15:58:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121956 SWODY1 SPC AC 121954 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0254 PM CDT FRI MAY 12 2006 VALID 122000Z - 131200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... DRY/STABLE AIR MASS ACROSS MUCH OF THE CONUS IS EXPECTED TO PRECLUDE ANY SEVERE THREAT THIS FORECAST PERIOD. A FEW REGIONS WILL... HOWEVER...HAVE SOME THUNDERSTORM ACTIVITY THIS AFTERNOON/EVENING AND/OR OVERNIGHT WITH THE GREATEST POTENTIAL ACROSS PARTS OF THE SOUTH CENTRAL STATES AND NRN ROCKIES. ...SW TX... A FEW THUNDERSTORMS HAVE ALREADY DEVELOPED OVER THE HIGHER TERRAIN OF SW TX /25 NE MRF/...WITH VISIBLE IMAGERY INDICATING ADDITIONAL CU/TCU DEVELOPING ALONG THE MOUNTAINS OF SW TX. STEEP LAPSE RATES AND SOME LARGE SCALE ASCENT WITH WEAK SHORT WAVE TROUGH...CURRENTLY MOVING SEWD ACROSS CENTRAL/SW TX...SHOULD ALLOW FOR A FEW ADDITIONAL DIURNAL STORMS ALONG THE HIGHER TERRAIN INTO THE EARLY EVENING. WEAK INSTABILITY WILL PRECLUDE A SEVERE WEATHER THREAT...THOUGH LARGE SURFACE DEWPOINT DEPRESSIONS MAY ALLOW FOR ISOLATED NON-SEVERE WIND GUSTS WITH ANY OF THE THUNDERSTORMS. ...NERN WA/FAR NRN ID INTO MT... SATELLITE IMAGERY/LIGHTNING DATA INDICATED THUNDERSTORMS HAD ALREADY DEVELOPED MAINLY ACROSS SERN BC. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE INTO THE EVENING SEWD ACROSS CENTRAL/ERN MT AS A SHORT WAVE TROUGH TRACKS EWD OVER THE NRN ROCKIES/SWRN CANADA. DESPITE MEAGER LOW-LEVEL MOISTURE...SURFACE HEATING AND STEEP LAPSE RATES WILL AID IN THE DEVELOPMENT OF HIGH BASED THUNDERSTORMS. ...ERN OK TO LOWER MS VALLEY... SLY LOW LEVEL FLOW DEVELOPING THIS FORECAST PERIOD ACROSS TX WILL ALLOW MOISTURE TO BEGIN RETURNING NWD...ESPECIALLY LATER TONIGHT. WAA...STEEP LAPSE RATES AND SOME LARGE SCALE ASCENT SPREADING SEWD ACROSS THIS REGION IN ASSOCIATION WITH A WEAK SHORT WAVE TROUGH EMBEDDED WITHIN NWLY FLOW ALOFT SHOULD ALLOW FOR ELEVATED TSTMS LATER THIS EVENING/OVERNIGHT ACROSS ERN OK INTO AR/NRN MS. ..PETERS.. 05/12/2006  From swody1 at goshenarc.org Sat May 13 05:15:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 01:15:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130513 SWODY1 SPC AC 130511 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1211 AM CDT SAT MAY 13 2006 VALID 131200Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CNTRL AND SRN AL THROUGH CNTRL AND SRN GA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN TX THROUGH THE LOWER MS VALLEY... ...SYNOPSIS... STAGNANT UPPER PATTERN WILL PERSIST THROUGH SATURDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND SHORTWAVE RIDGING OVER THE ROCKIES. SERIES OF VORTICITY MAXIMA WILL CONTINUE TO ROTATE THROUGH THE UPPER LOW. ONE SUCH FEATURE WILL MOVE SEWD INTO THE SERN STATES DURING THE DAY. A COLD FRONT WILL MOVE PROGRESSIVELY SWD AND BY LATE AFTERNOON SHOULD EXTEND FROM A SURFACE LOW OVER THE OH VALLEY SWWD INTO THE TN VALLEY...THEN WNWWD INTO SRN KS. ...CNTRL AL THROUGH CNTRL AND SRN GA... LOW LEVEL MOISTURE WILL REMAIN SOMEWHAT LIMITED THROUGH SATURDAY OVER THE SERN STATES...AND THIS WILL LIKELY SERVE AS AN OVERALL LIMITING FACTOR FOR A MORE ROBUST SEVERE WEATHER THREAT. CURRENT OBSERVATIONS SHOW SURFACE DEWPOINTS GENERALLY IN THE UPPER 40S TO LOWER 50S AND MUCH OF THIS MOISTURE IS CONFINED TO NEAR THE SURFACE. RICHER LOW LEVEL MOISTURE IS WELL SW OF THIS AREA IN SRN TX. WITH LITTLE IN THE WAY OF SIGNIFICANT MOISTURE ADVECTION...BOUNDARY LAYER MIXING SHOULD RESULT IN DEWPOINTS REMAINING IN THE UPPER 40S TO NEAR 50 DURING THE DAY. DESPITE THE LIMITED LOW LEVEL MOISTURE...STEEP LAPSE RATES AND SURFACE HEATING WILL RESULT IN SOME DESTABILIZATION WITH MLCAPE AOB 500 J/KG. A FEW ELEVATED STORMS MAY BE ONGOING WITHIN ZONE OF WARM ADVECTION AND ASCENT ASSOCIATED WITH A WLY LOW LEVEL JET AND SEWD ADVANCING SHORTWAVE TROUGH. POTENTIAL WILL EXIST FOR SOME OF THIS ACTIVITY TO INTENSIFY AND BECOME SURFACE BASED AS THE DOWNSTREAM ATMOSPHERE DESTABILIZES. THERMODYNAMIC PROFILES WILL LIKELY BE CHARACTERIZED BY INVERTED-V BOUNDARY LAYERS WITH UPDRAFTS HAVING RELATIVELY HIGH BASES. PRIMARY THREAT WILL BE ISOLATED DAMAGING WIND AND MARGINALLY SEVERE HAIL AS ACTIVITY SPREADS ESEWD. THREAT SHOULD DIMINISH BY EARLY EVENING. ...NERN TX...EXTREME SERN OK THROUGH THE LOWER MS VALLEY... PARTIALLY MODIFIED GULF AIR WITH DEWPOINTS IN THE LOWER 60S SHOULD BEGIN RETURNING NWD THROUGH TX BENEATH STEEP MID LEVEL LAPSE RATES BY SATURDAY NIGHT AS THE NOCTURNAL LOW LEVEL JET INCREASES. STORMS ARE EXPECTED TO DEVELOP WITHIN ZONE OF INCREASING WARM ADVECTION AND LIFT FROM NERN TX SPREADING EWD INTO THE LOWER MS VALLEY REGION. ACTIVITY WILL LIKELY BE ELEVATED...BUT THERMODYNAMIC PROFILES APPEAR SUFFICIENT FOR A THREAT FOR HAIL WITHIN THE STRONGER STORMS. ..DIAL/CROSBY.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 12:33:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 08:33:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131231 SWODY1 SPC AC 131229 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 AM CDT SAT MAY 13 2006 VALID 131300Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE GULF COAST REGION... ...AL/GA... MORNING WATER VAPOR IMAGERY SHOWS A LARGE UPPER LOW OVER THE EASTERN STATES...WITH SEVERAL WEAK DISTURBANCES ROTATING AROUND BASE OF LOW AND ACROSS THE MS VALLEY AND GULF COAST REGION. ONE SUCH FEATURE IS EVIDENT THIS MORNING OVER MO/AR. THIS TROUGH IS EXPECTED TO TRACK EAST-SOUTHEASTWARD ACROSS PARTS OF AL/MS/GA BY EVENING. AIR MASS AHEAD OF THIS FEATURE WILL BECOME MODERATELY UNSTABLE THIS AFTERNOON AS STRONG DAYTIME HEATING AND VERTICAL MIXING OCCUR. VERTICAL SHEAR WILL ALSO BE QUITE FAVORABLE FOR ORGANIZED/SUPERCELL STORMS. PRESENT INDICATIONS ARE THAT MORNING STORMS WILL PERSIST FOR SEVERAL MORE HOURS...EVENTUALLY TRACKING INTO WESTERN GA BEFORE WEAKENING. HAIL WILL REMAIN THE PRIMARY THREAT WITH THIS ISOLATED ACTIVITY THROUGH MIDDAY. MODELS GENERALLY AGREE ON THE REDEVELOPMENT OF STRONG/SEVERE STORMS OVER MIDDLE TN/NORTHERN AL NEAR/AFTER SUNSET AS NOCTURNAL LOW LEVEL JET STRENGTHENS. THESE STORMS WILL LIKELY BE CAPABLE OF LARGE NAIL AND DAMAGING WINDS FOR A FEW HOURS DURING THE EVENING. ...TX/LA/MS.... FARTHER WEST ACROSS PORTIONS OF MS AND THE ARKLATEX...CONVECTIVE INITIATION WILL BE LATER TONIGHT. STEEP LOW/MID LEVEL LAPSE RATES ARE LIKELY TO DEVELOP ALONG AND SOUTH OF SURFACE FRONT EXTENDING FROM NORTH TX INTO CENTRAL MS. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER DARK ALONG FRONT...SAGGING SLOWLY SOUTHWARD OVERNIGHT. A FEW SEVERE STORMS WILL BE POSSIBLE...CAPABLE OF HAIL AND DAMAGING WINDS. ..HART/CROSBIE.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 16:36:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 12:36:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131628 SWODY1 SPC AC 131627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT SAT MAY 13 2006 VALID 131630Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN TX EWD ACROSS LOWER MS VALLEY INTO GA... ...SYNOPSIS... AS UPPER LOW NOW OVER SRN WI DROPS SEWD INTO OH VALLEY STRONG WIND MAX CURRENTLY VICINITY MKC WILL MOVE ACROSS LOWER MO VALLEY INTO TN VALLEY BY THIS EVENING. COLD FRONT FROM SRN WI SURFACE LOW TRAILS SWWD ACROSS MO INTO NERN OK AND THEN WWD ACROSS TX PANHANDLE. FRONT WILL MOVE SLOWLY SWD EXTENDING FROM TN/AR BORDER WSWWD TO VICINITY NRN TX/OK BORDER BY THIS EVENING. STEEP MID LEVEL LAPSE RATES HAVE SPREAD EWD ACROSS SRN STATES AHEAD OF COLD FRONT WHICH ALONG WITH THE STRONG VEERING SHEAR PROFILES IS PROVIDING A SET UP FOR POTENTIALLY AN ACTIVE SEVERE THUNDERSTORM PERIOD. THE ONE CAVEAT WILL BE QUALITY OF LOW LEVEL MOISTURE WHICH IS RETURNING NEWD FROM WRN GULF ACROSS TX INTO LOWER MS VALLEY ATTM. ...GULF STATES... STRONG HEATING WILL PUSH SURFACE TEMPERATURES TO 80F OR ABOVE ACROSS MUCH OF GULF STATES THIS AFTERNOON. WITH LAPSE RATES IN EXCESS OF 7C/KM COUPLED WITH 40-50KT OF DEEP LAYER SHEAR THE INHIBITION WILL WEAKEN SUFFICIENTLY FOR THUNDERSTORMS TO DEVELOP BY MID AFTERNOON. THIS MORNINGS ELEVATED ACTIVITY SHOULD RESULT IN PROVIDING SURFACE BOUNDARIES TO FOCUS INITIATION THIS AFTERNOON FROM NRN MS INTO CENTRAL AL/GA. WITH STILL LIMITED LOW LEVEL MOISTURE...MLCAPES TO 1000 J/KG ARE ALL THAT ARE EXPECTED IN THIS REGION...WHICH WILL LIMIT THE INTENSITY OF STORMS. HOWEVER HAIL...SOME SEVERE...IS LIKELY WITH MANY OF THE STORMS CONSIDERING THE COOL...STEEP LAPSE RATES AND STRONG SHEAR. ADDITIONALLY STEEP LOW LEVEL LAPSE RATES WILL ENHANCE LOCAL DAMAGING WIND POTENTIAL. ...LOWER MS VALLEY INTO NRN TX... HAVE EXPANDED AND INCREASED THE THREAT OF SEVERE THUNDERSTORMS...PARTICULARLY OF LARGE HAIL...FOR LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS FROM NRN TX EWD TO MS. MODELS APPEAR TO BE HAVING CONSIDERABLE DIFFICULTY HANDLING THE ONGOING SHALLOW MOISTURE RETURN ACROSS TX. NAM AND EVEN THE 12Z GFS RUNS SEEMS TO EXCESSIVELY INCREASE BOUNDARY LAYER MOISTURE AHEAD OF COLD FRONT ACROSS NERN TX WITH FORECASTS OF NEAR 70F DEWPOINT LATE THIS AFTERNOON. OBSERVED MOISTURE SUGGEST POSSIBLE LOW/MID 60S CAN BE EXPECTED WHICH COUPLED WITH STRONG HEATING...INCREASINGLY FAVORABLE DEEP LAYER SHEAR AS WIND MAX ROTATES SEWD TOWARD WRN TN VALLEY...STILL SUPPORT SEVERE THUNDERSTORMS. WITH MLCAPES LIKELY BETWEEN 2000-2500 J/KG BY LATER THIS AFTERNOON AND LITTLE CIN AS TEMPERATURES HEAT THRU THE 80S...STORMS SHOULD INITIATE...MOST LIKELY BY EVENING ALONG/AHEAD OF COLD FRONT DROPPING SWD ACROSS SRN AR INTO NRN TX. SUPERCELLS WILL DEVELOP WHICH WILL ENHANCE POTENTIAL FOR VERY LARGE HAIL BY LATE AFTERNOON INTO OVERNIGHT HOURS ACROSS NRN TX EWD INTO MS. TORNADO POTENTIAL WILL BE LIMITED BY EXPECTED HIGH LCLS AND WEAKER SHEAR IN AREA OF BEST INSTABILITY ACROSS ERN TX AND WEAKER INSTABILITY FURTHER E WHERE THE SHEAR WILL BE STRONGER. POTENTIAL FOR SEVERE STORMS WILL CONTINUE WELL AFTER DARK AS ACTIVITY GRADUALLY SHIFTS S/SEWD ACROSS ERN TX AND LOWER MS VALLEY AS SHEAR WILL REMAIN QUITE FAVORABLE WITH PROXIMITY OF UPPER LOW AND WIND MAX TO THE N. WILL MONITOR THE MOISTURE FOR POSSIBLE UPGRADE FOR PORTIONS OF THE SLIGHT RISK IF INSTABILITY CAN INCREASE TO A GREATER DEGREE THAN NOW EXPECTED. ..HALES/GRAMS.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 20:04:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 16:04:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 132000 SWODY1 SPC AC 131959 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0259 PM CDT SAT MAY 13 2006 VALID 132000Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN TX EWD ACROSS LOWER MS VALLEY INTO GA... ...GULF STATES... SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING FROM WRN TN SWWD INTO CENTRAL AR AND THEN WWD THROUGH CENTRAL OK TO THE TX PANHANDLE. AN OUTFLOW BOUNDARY FROM EARLIER CONVECTION ACROSS AL/GA EXTENDED FROM SWRN GA/SERN AL WNWWD ACROSS SRN TO WRN AL TO NRN MS. MOISTURE RETURN ACROSS THE GULF COAST STATES HAS BEEN SOMEWHAT LIMITED THUS FAR PRIMARILY TO THE SURFACE/NEAR SURFACE LAYER. HOWEVER...PRESENCE OF STEEP MID LEVEL LAPSE RATES IS CONTRIBUTING TO SBCAPE VALUES AROUND 1500 J/KG OVER SRN AL TO 2000 J/KG IN NRN MS WHERE SURFACE DEWPOINTS WERE HIGHER. INCREASING LARGE SCALE ASCENT SPREADING SEWD ACROSS TN VALLEY AND GULF COAST STATES THIS AFTERNOON/EVENING WITH THE APPROACH OF SRN MO/NRN AR SHORT WAVE TROUGH/MID LEVEL SPEED MAX EXPECTED TO AID IN THUNDERSTORM DEVELOPMENT. HAIL WILL BE LIKELY WITH MANY OF THE STORMS GIVEN STRONG DEEP LAYER SHEAR AND STEEP LAPSE RATES...WHILE INDICATION OF LOW RH VALUES/DRY AIR IN LOW LEVELS PER 1730Z ACARS DATA AT MEM SHOULD PROMOTE POTENTIAL FOR STRONG WIND GUSTS. ALTHOUGH ERN PARTS OF AL/CENTRAL GA ARE RATHER STABLE PER CLOUDINESS LEFT OVER FROM EARLIER CONVECTION...SLIGHT RISK WILL BE MAINTAINED ACROSS THIS REGION GIVEN POTENTIAL FOR UPSTREAM STORMS...ONCE THEY DEVELOP...TO TRACK INTO THIS AREA LATER THIS EVENING. ...LOWER MS VALLEY INTO NRN TX... NWD MOISTURE RETURN IS ONGOING FROM THE TX COAST TO CENTRAL/ERN PARTS OF THE RED RIVER VALLEY. SURFACE TEMPERATURES RISING THROUGH THE 80S BENEATH A PLUME OF STEEP LAPSE RATES WERE CONTRIBUTING TO INCREASING INSTABILITY AS EXPECTED PER EARLIER OUTLOOK. HOWEVER... THESE STEEP LAPSE RATES WERE ALSO RESULTING IN A STRONG CAP THAT IS EXPECTED TO PRECLUDE SURFACE BASED DEVELOPMENT ALONG THE SWD MOVING COLD FRONT UNTIL THIS EVENING ACROSS NRN TX INTO SRN AR. MOISTURE ADVECTION THROUGH THE FORECAST PERIOD SHOULD RESULT IN MLCAPE VALUES UP TO 2500 ACROSS ERN TX LATE THIS AFTERNOON. INSTABILITY EXPECTED TO REMAIN STRONG INTO THE OVERNIGHT PERIOD AS STRENGTHENING SSWLY LLJ AIDS IN NWD MOISTURE TRANSPORT AND INCREASING WAA. ONCE STORMS DEVELOP...STRONG DEEP LAYER SHEAR...PER PROXIMITY OF MID LEVEL WIND MAX EXTENDING FROM ERN KS TO TN VALLEY...AND STRONG INSTABILITY WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS. AS COLD FRONT MOVES SWD ACROSS ERN TX/LOWER MS VALLEY TONIGHT...SEVERE THREAT EXPECTED TO PERSIST WELL AFTER DARK GIVEN PROGGED MAGNITUDE OF ELEVATED INSTABILITY/BULK SHEAR. ...ERN PA INTO PARTS OF CENTRAL/WRN NY... AFTERNOON WATER VAPOR IMAGERY INDICATED SEVERAL VORTICITY MAXIMA ROTATING AROUND THE ERN PERIPHERY OF THE LARGE ERN STATES UPPER CYCLONE. ONE SUCH MID LEVEL IMPULSE WAS LOCATED OVER NERN PA/ CENTRAL NY AND AIDING WITH ONGOING THUNDERSTORMS ACROSS ERN PA NNWWD INTO CENTRAL/WRN NY. ADDITIONAL LARGE SCALE ASCENT IS EXPECTED TO SPREAD NWD ACROSS THIS SAME REGION LATER THIS AFTERNOON/EVENING AS A PAIR OF UPSTREAM IMPULSES LOCATED OVER SERN VA AND CENTRAL NC AT 18Z ROTATE NWD. WEAK LOW-LEVEL CONVERGENCE ALONG SURFACE TROUGH AND ASCENT WITH VORTICITY MAXIMA EXPECTED TO SUPPORT ADDITIONAL THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING. WEAK INSTABILITY /MLCAPE 500-800 J/KG/ AND MODEST DEEP LAYER SHEAR /20-25 KT/ SHOULD LIMIT STORM ORGANIZATION...THOUGH A FEW STORMS MAY BECOME STRONG ENOUGH TO PRODUCE MARGINALLY SEVERE HAIL AND/OR STRONG WIND GUSTS. ..PETERS.. 05/13/2006  From swody1 at goshenarc.org Sun May 14 01:06:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 21:06:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140101 SWODY1 SPC AC 140100 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0800 PM CDT SAT MAY 13 2006 VALID 140100Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF NERN TX INTO EXTREME SERN OK...THE LOWER MS VALLEY AND PARTS OF THE SERN STATES... ...SRN PORTIONS OF TN VALLEY THROUGH PORTIONS OF THE SERN STATES... ZONE OF LARGE SCALE ASCENT ASSOCIATED WITH EXIT REGION OF A SEWD MOVING JET STREAK IS CONTRIBUTING TO THE DEVELOPMENT OF SCATTERED THUNDERSTORMS FROM CNTRL AND NRN AL THROUGH PART OF NRN GA AND SRN TN. INSTABILITY IS SOMEWHAT LIMITED WITH BOUNDARY LAYER DEWPOINTS GENERALLY IN THE 50S...BUT STEEP LAPSE RATES AND BOUNDARY LAYER WARMING HAVE RESULTED IN MLCAPE ON THE ORDER OF 500 TO 1000 J/KG. STRONG DEEP LAYER SHEAR OF 50+ KT ENHANCED BY THE UPPER JET AND CHARACTERIZED BY SSWLY LOW LEVEL FLOW VEERING TO NWLY AT 6 KM IS RESULTING IN A FAVORABLE KINEMATIC ENVIRONMENT FOR STORMS TO ROTATE. STEEP MID LEVEL LAPSE RATES AND COOL THERMODYNAMIC PROFILES AS WELL AS POTENTIAL FOR MID LEVEL UPDRAFT ROTATION ARE CONTRIBUTING TO A THREAT FOR LARGE HAIL WITHIN THE STRONGER STORMS. ISOLATED DAMAGING WIND IS ALSO POSSIBLE GIVEN THE RELATIVELY DRY BOUNDARY LAYERS. SEVERE THREAT IS EXPECTED TO PERSIST AT LEAST INTO THE MID EVENING AS THE ATMOSPHERE DESTABILIZES EWD INTO GA AND WRN PARTS OF THE CAROLINAS. ...NERN TX...EXTREME SERN OK THROUGH THE LOWER MS VALLEY... A SURFACE FRONT EXTENDS FROM CNTRL AR WWD INTO SRN OK. THIS BOUNDARY WILL LIKELY SHIFT SWD INTO NRN TX AND SRN AR OVERNIGHT AS AN UPPER LEVEL JET SHIFTS SEWD THROUGH THE TN VALLEY. THE ATMOSPHERE S OF THIS BOUNDARY HAS BECOME QUITE UNSTABLE WITH STEEP MID LEVEL LAPSE RATES AND COOL MID LEVEL TEMPERATURES ABOVE BOUNDARY LAYER DEWPOINTS IN THE 60S. THE 00Z FORT WORTH RAOB SHOWS 3000 J/KG OF MLCAPE AND 8.9 C/KM LAPSE RATES BETWEEN 700 AND 500 MB. HOWEVER...IT ALSO SHOWS A RATHER PRONOUNCED CAP. A SLY LOW LEVEL JET WILL INCREASE TONIGHT ACROSS TX AND IMPINGE ON THE SWD MOVING BOUNDARY. LIFT ASSOCIATED WITH WARM ADVECTION AND INCREASING FRONTOGENETIC FORCING IN THE VICINITY OF THE BOUNDARY SHOULD EVENTUALLY WEAKEN THE CAP AND CONTRIBUTE TO THUNDERSTORM INITIATION LATER THIS EVENING FROM NERN TX INTO THE LOWER MS VALLEY. GIVEN THE VERY STEEP MID LEVEL LAPSE RATES AND SUPERCELL WIND PROFILES...VERY LARGE HAIL COULD ACCOMPANY THE STRONGER STORMS. ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE. ..DIAL.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 06:01:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 02:01:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140557 SWODY1 SPC AC 140555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN NM THROUGH CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS VA THROUGH THE CNTRL AND ERN CAROLINAS...SRN GA AND THE FL PANHANDLE... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THROUGH SUNDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND UPPER RIDGING OVER THE ROCKIES. A STRONG MID LEVEL JET WILL CONTINUE TO ROTATE SEWD THROUGH THE BASE OF THE UPPER TROUGH INTO THE SERN U.S. AND CAROLINAS. AS THIS OCCURS THE COLD FRONT CURRENTLY FROM THE TN VALLEY WWD THROUGH NRN TX WILL CONTINUE TO PUSH SWD DURING THE DAY. ...SERN NM THROUGH CNTRL AND SRN TX... LOW LEVEL DEWPOINTS IN THE UPPER 60S TO NEAR 70 WILL PERSIST OVER S CNTRL THROUGH S TX IN THE PRE-FRONTAL WARM SECTOR BENEATH STEEP MID LEVEL LAPSE RATES. THIS WILL RESULT IN STRONG INSTABILITY BY SUNDAY AFTERNOON AS THE BOUNDARY LAYER WARMS WITH MLCAPE FROM 2500 TO 3000 J/KG. STORMS MAY BE ONGOING SUNDAY MORNING OVER PARTS OF CNTRL TX. ACTIVITY SHOULD REDEVELOP AND INTENSIFY DURING THE AFTERNOON WITHIN ZONE OF FRONTOGENETIC FORCING ALONG SWD ADVANCING FRONT. ENELY BOUNDARY LAYER FLOW VEERING TO NWLY AT 6 KM WILL RESULT IN FAVORABLE VERTICAL SHEAR FOR ORGANIZED STORMS INCLUDING SUPERCELLS. THERMODYNAMIC PROFILES APPEAR SUPPORTIVE OF VERY LARGE HAIL...ESPECIALLY WITH ANY DISCRETE SUPERCELL STRUCTURES. ISOLATED DAMAGING WIND MAY ALSO BE POSSIBLE...ESPECIALLY WITH ANY STORMS THAT MANAGE TO EVOLVE INTO LINES OR CLUSTERS. OTHER STORMS MAY DEVELOP OVER THE HIGHER TERRAIN OF SERN NM WHERE SURFACE HEATING AND EVOLVING UPSLOPE REGIME SHOULD SUPPORT INITIATION BY MID AFTERNOON. LOW LEVEL MOISTURE WILL BE MORE LIMITED IN THIS REGION WITH MLCAPE BELOW 1000 J/KG. SUPERCELLS WITH LARGE HAIL WILL BE THE PRIMARY THREAT. ...VA THROUGH THE CNTRL AND ERN CAROLINAS INTO SRN GA AND THE FL PANHANDLE... FORCING FOR ASCENT ASSOCIATED WITH EXIT REGION OF MID LEVEL JET WILL SPREAD EWD INTO THE CAROLINAS AND MID ATLANTIC DURING THE DAY. CONVECTION CURRENTLY MOVING EWD THROUGH THE CAROLINAS WILL LIKELY WEAKEN OWING TO LIMITED INSTABILITY. HOWEVER...SOME RESIDUAL CLOUDS AND THUNDERSTORMS MAY STILL BE IN PROGRESS EARLY SUNDAY MORNING. LOW LEVEL MOISTURE WILL REMAIN MORE LIMITED FROM THE CAROLINAS INTO VA. HOWEVER...COLD MID LEVEL TEMPERATURES WITH -18 TO -20 AT 500 MB WILL CONTRIBUTE TO STEEP MID LEVEL LAPSE RATES. WHERE SURFACE HEATING DEVELOPS...THE ATMOSPHERE WILL DESTABILIZE WITH MLCAPE FROM 500 TO 1000 J/KG. FARTHER S OVER S GA INTO THE FL PANHANDLE...RICHER LOW LEVEL MOISTURE WILL EXIST...BUT THIS WILL BE OFFSET SOMEWHAT BY WARMER MID LEVEL TEMPERATURES S OF UPPER JET. STORMS SHOULD REDEVELOP AND INTENSIFY BY EARLY AFTERNOON AS THE ATMOSPHERE DESTABILIZES WITHIN ZONE OF ASCENT ASSOCIATED WITH JET EXIT REGION FROM ERN GA THROUGH THE CAROLINAS INTO VA. STRONG VERTICAL SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING POTENTIAL FOR SUPERCELLS AS WELL AS LINES WITH DAMAGING WIND AND LARGE HAIL THE PRIMARY THREATS THROUGH EARLY EVENING. OTHER ACTIVITY MAY DEVELOP SWWD INTO SRN GA AND THE FL PANHANDLE ALONG SURFACE BOUNDARY AND WITHIN JET ENTRANCE REGION BY LATE AFTERNOON INTO THE EVENING. ..DIAL/CROSBY.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 06:01:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 02:01:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140557 SWODY1 SPC AC 140555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN NM THROUGH CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS VA THROUGH THE CNTRL AND ERN CAROLINAS...SRN GA AND THE FL PANHANDLE... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THROUGH SUNDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND UPPER RIDGING OVER THE ROCKIES. A STRONG MID LEVEL JET WILL CONTINUE TO ROTATE SEWD THROUGH THE BASE OF THE UPPER TROUGH INTO THE SERN U.S. AND CAROLINAS. AS THIS OCCURS THE COLD FRONT CURRENTLY FROM THE TN VALLEY WWD THROUGH NRN TX WILL CONTINUE TO PUSH SWD DURING THE DAY. ...SERN NM THROUGH CNTRL AND SRN TX... LOW LEVEL DEWPOINTS IN THE UPPER 60S TO NEAR 70 WILL PERSIST OVER S CNTRL THROUGH S TX IN THE PRE-FRONTAL WARM SECTOR BENEATH STEEP MID LEVEL LAPSE RATES. THIS WILL RESULT IN STRONG INSTABILITY BY SUNDAY AFTERNOON AS THE BOUNDARY LAYER WARMS WITH MLCAPE FROM 2500 TO 3000 J/KG. STORMS MAY BE ONGOING SUNDAY MORNING OVER PARTS OF CNTRL TX. ACTIVITY SHOULD REDEVELOP AND INTENSIFY DURING THE AFTERNOON WITHIN ZONE OF FRONTOGENETIC FORCING ALONG SWD ADVANCING FRONT. ENELY BOUNDARY LAYER FLOW VEERING TO NWLY AT 6 KM WILL RESULT IN FAVORABLE VERTICAL SHEAR FOR ORGANIZED STORMS INCLUDING SUPERCELLS. THERMODYNAMIC PROFILES APPEAR SUPPORTIVE OF VERY LARGE HAIL...ESPECIALLY WITH ANY DISCRETE SUPERCELL STRUCTURES. ISOLATED DAMAGING WIND MAY ALSO BE POSSIBLE...ESPECIALLY WITH ANY STORMS THAT MANAGE TO EVOLVE INTO LINES OR CLUSTERS. OTHER STORMS MAY DEVELOP OVER THE HIGHER TERRAIN OF SERN NM WHERE SURFACE HEATING AND EVOLVING UPSLOPE REGIME SHOULD SUPPORT INITIATION BY MID AFTERNOON. LOW LEVEL MOISTURE WILL BE MORE LIMITED IN THIS REGION WITH MLCAPE BELOW 1000 J/KG. SUPERCELLS WITH LARGE HAIL WILL BE THE PRIMARY THREAT. ...VA THROUGH THE CNTRL AND ERN CAROLINAS INTO SRN GA AND THE FL PANHANDLE... FORCING FOR ASCENT ASSOCIATED WITH EXIT REGION OF MID LEVEL JET WILL SPREAD EWD INTO THE CAROLINAS AND MID ATLANTIC DURING THE DAY. CONVECTION CURRENTLY MOVING EWD THROUGH THE CAROLINAS WILL LIKELY WEAKEN OWING TO LIMITED INSTABILITY. HOWEVER...SOME RESIDUAL CLOUDS AND THUNDERSTORMS MAY STILL BE IN PROGRESS EARLY SUNDAY MORNING. LOW LEVEL MOISTURE WILL REMAIN MORE LIMITED FROM THE CAROLINAS INTO VA. HOWEVER...COLD MID LEVEL TEMPERATURES WITH -18 TO -20 AT 500 MB WILL CONTRIBUTE TO STEEP MID LEVEL LAPSE RATES. WHERE SURFACE HEATING DEVELOPS...THE ATMOSPHERE WILL DESTABILIZE WITH MLCAPE FROM 500 TO 1000 J/KG. FARTHER S OVER S GA INTO THE FL PANHANDLE...RICHER LOW LEVEL MOISTURE WILL EXIST...BUT THIS WILL BE OFFSET SOMEWHAT BY WARMER MID LEVEL TEMPERATURES S OF UPPER JET. STORMS SHOULD REDEVELOP AND INTENSIFY BY EARLY AFTERNOON AS THE ATMOSPHERE DESTABILIZES WITHIN ZONE OF ASCENT ASSOCIATED WITH JET EXIT REGION FROM ERN GA THROUGH THE CAROLINAS INTO VA. STRONG VERTICAL SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING POTENTIAL FOR SUPERCELLS AS WELL AS LINES WITH DAMAGING WIND AND LARGE HAIL THE PRIMARY THREATS THROUGH EARLY EVENING. OTHER ACTIVITY MAY DEVELOP SWWD INTO SRN GA AND THE FL PANHANDLE ALONG SURFACE BOUNDARY AND WITHIN JET ENTRANCE REGION BY LATE AFTERNOON INTO THE EVENING. ..DIAL/CROSBY.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 12:23:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 08:23:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141220 SWODY1 SPC AC 141219 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0719 AM CDT SUN MAY 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SOUTHERN PLAINS AND LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC REGION INTO THE SOUTHEAST STATES... ...LA/TX... MORNING WATER VAPOR IMAGERY SHOWS LARGE UPPER LOW OVER THE EASTERN STATES...WITH BAND OF STRONG NORTHWEST FLOW ALOFT EXTENDING FROM THE CENTRAL PLAINS INTO THE CENTRAL GULF COAST REGION. CLUSTER OF SEVERE STORMS IS ONGOING THIS MORNING OVER EAST TX. THESE STORMS APPEAR TO BE IN RIGHT ENTRANCE REGION OF CYCLONIC UPPER JET MAX OVER THE MS VALLEY...AND WILL LIKELY CONTINUE THROUGH THE MORNING HOURS. PRESENT INDICATIONS ARE THAT ACTIVITY WILL SPREAD SOUTHWARD TOWARD THE UPPER TX GULF COAST BY MIDDAY WITH THE POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS. OTHER STORMS ARE LIKELY TO DEVELOP WESTWARD FROM THIS ACTIVITY BY MID/LATE AFTERNOON ACROSS CENTRAL TX. HIGH CAPE VALUES EXCEEDING 4000 J/KG AND BACKED LOW LEVEL WINDS WILL ENHANCE THE RISK OF SUPERCELLS CAPABLE OF VERY LARGE HAIL. THESE STORMS MAY DEVELOP INTO SOUTH TX TONIGHT BEFORE WEAKENING. FINALLY...ISOLATED SEVERE STORMS WILL BE POSSIBLE OVER SOUTHEAST NM AND WEST TX IN LOW LEVEL UPSLOPE FLOW REGIME. PRESENT INDICATIONS ARE THAT WEAK INSTABILITY WILL LIMIT AREAL COVERAGE OF SEVERE STORMS IN THAT REGION. ...MID ATLANTIC INTO SOUTHEAST STATES... MID/UPPER LEVEL SPEED MAX WILL ROTATE FROM THE MS/TN VALLEY INTO THE MID ATLANTIC REGION BY THIS AFTERNOON. THIS WILL RESULT IN INCREASING FORCING FOR UPWARD VERTICAL MOTION FROM CENTRAL VA ACROSS THE CAROLINAS BY EARLY AFTERNOON. LOW LEVEL MOISTURE VALUES ARE ONLY MARGINAL WITH SURFACE DEWPOINTS GENERALLY IN THE LOW/MID 50S. HOWEVER...COLD TEMPERATURES ALOFT /500MB TEMPERATURES OF -18 TO -20C/ AND STEEP LAPSE RATES WILL PROMOTE RAPID DESTABILIZATION WITH A FEW HOURS OF HEATING...AND THE RISK OF HAIL IN STRONGER CELLS. VERTICAL SHEAR PROFILES WILL ALSO BE FAVORABLE FOR SUPERCELLS AND ISOLATED TORNADOES. ACTIVITY IS EXPECTED TO SPREAD OFF THE VA/CAROLINA COAST BY EARLY EVENING...ENDING THE THREAT OF SEVERE STORMS. ISOLATED STRONG/SEVERE STORMS MAY ALSO EXTEND SOUTHWESTWARD FROM PRIMARY ACTIVITY...INTO PARTS OF GA/AL/FL THIS AFTERNOON IN MOIST/UNSTABLE AIR MASS. ..HART.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 16:27:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 12:27:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141612 SWODY1 SPC AC 141610 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1110 AM CDT SUN MAY 14 2006 VALID 141630Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS THE GULF STATES TO THE MID ATLANTIC COAST... ...SYNOPSIS... LARGE UPPER COLD LOW MOVES SLOWLY EWD ACROSS OH VALLEY THRU TONIGHT AS A STRONG MID LEVEL WIND MAX NOW ACROSS TN VALLEY CONTINUES ROTATING EWD TO ACROSS CAROLINAS BY THIS EVENING. SLOWLY DEVELOPING SURFACE LOW FAR WRN VA WILL MOVE EWD VICINITY VA/NC BORDER THIS AFTERNOON IN CONCERT WITH THE PRONOUNCED EXIT REGION OF THE STRONG MID LEVEL JET. COLD FRONT TRAILS WSWWD ACROSS NRN GA TO SRN AR AND THEN INTO FAR SWRN TX. ...MID ATLANTIC REGION... STEEP MID LEVEL LAPSE RATES HAVE SPREAD EWD ACROSS THE MID ATLANTIC STATES AHEAD OF APPROACHING UPPER LEVEL LOW AND WIND MAX. AS THE SURFACE LOW WRN VA MOVES EWD...LOW LEVEL WINDS ACROSS SERN VA INTO NERN NC WILL BACK AND GRADUALLY INCREASE THRU THE AFTERNOON...PROVIDING A FAVORABLE SUPERCELL ENVIRONMENT. LOW LEVEL MOISTURE SUFFICIENT GIVEN COOL...STEEP LAPSE RATES FOR MLCAPES RISING TO 1000 J/KG WHERE SURFACE TEMPERATURES CAN HEAT INTO THE LOW/MID 70S. WHILE HAIL WILL BE PRIMARY THREAT AS STORMS DEVELOP BY EARLY THIS AFTERNOON GIVEN THE FAVORABLE FREEZING LEVELS...THERE WILL BE SUFFICIENT SPEED AND DIRECTIONAL SHEAR FOR SUPERCELL FORMATION. MOST FAVORABLE SUPERCELL AREA ALONG WITH ISOLATED TORNADO POTENTIAL WILL BE IN ADVANCE OF SURFACE LOW UNDER APPROACHING STRONG MID LEVEL JET. STORMS ALSO COULD EVOLVE INTO SHORT LINES/BOWS UNDER THE STRONG UPPER JET FOR A MORE ORGANIZED WIND THREAT. ...TX TO LOWER MS VALLEY... A MUCH MORE UNSTABLE AIR MASS IS IN PLACE ACROSS CENTRAL/SRN TX TO S OF FRONTAL ZONE. ONGOING STRONG/SEVERE THUNDERSTORMS EXPECTED WITH AFTERNOON HEATING TO INCREASE IN NUMBER AND INTENSITY AS THE STORMS CONTINUE DEVELOPING S/SEWD THRU MUCH OF TX BY LATER TONIGHT. GIVEN MLCAPES RISING TO ABOVE 3000 J/KG AND 40-45 KT OF DEEP LAYER SHEAR...VERY LARGE HAIL WILL BE THE DOMINANT THREAT. THERMODYNAMIC PARAMETERS GIVEN THE DEEP LAYER SHEAR ALSO SUPPORT SUPERCELL POTENTIAL. LARGEST HAIL ALONG WITH ISOLATED TORNADOES WOULD BE ASSOCIATED WITH ANY SUPERCELL THAT DEVELOPS. SEVERE STORMS WILL PROPAGATE INTO THE VERY UNSTABLE AIR MASS ACROSS S TX AND LIKELY CONTINUE AFTER DARK. FURTHER E ALONG GULF COAST...WHILE LAPSE RATES FAVOR A FEW SEVERE STORMS...INSTABILITY AND SHEAR WILL BE A LITTLE LESS THAN THE AFOREMENTION AREAS. SEVERE POTENTIAL THUS WOULD BE MORE WIDELY SCATTERED WITH LARGE HAIL THE DOMINANT THREAT. ...SRN HIGH PLAINS... UPSLOPE FLOW HAS SPREAD WWD INTO ERN NM AND W OF PECOS VALLEY IN FAR SWRN TX ALONG WITH LOW LEVEL MOISTURE. VERY STEEP LAPSE RATES ABOVE SHALLOW SURFACE MOISTURE PERSIST THIS REGION. STRONG HEATING COUPLED WITH 40-50 KT OF DEEP LAYER SHEAR WILL BE ADEQUATE FOR A FEW SEVERE THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN ERN NM/SWRN TX. IN THE NWLY FLOW...STORMS WOULD THEN DEVELOP S/SEWD THRU THE HIGH PLAINS DURING EVENING WITH LARGE HAIL AND LOCAL DOWNBURSTS THE PRIMARY CONCERN. ..HALES/GRAM.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 20:09:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 16:09:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 142006 SWODY1 SPC AC 142004 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0304 PM CDT SUN MAY 14 2006 VALID 142000Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS THE GULF COAST STATES TO THE MID ATLANTIC REGION... ...MID ATLANTIC REGION... SC/NC/VA WILL REMAIN WITHIN EXIT REGION OF STRONG /70-80 KT/ MID LEVEL JET ROUNDING BASE OF LARGE UPPER CYCLONE NOW CENTERED OVER THE LOWER OH VALLEY. THIS WILL MAINTAIN FORCING FOR UPWARD VERTICAL MOTION AND ASSOCIATED SURFACE PRESSURE FALLS ACROSS THIS REGION FOR ADDITIONAL THUNDERSTORMS THROUGH THE REMAINDER OF THE AFTERNOON INTO THIS EVENING. STRONG FORCING AND KINEMATICS ASSOCIATED WITH SHORT WAVE TROUGH ROTATING NEWD ACROSS CAROLINAS/ MID ATLANTIC REGION WILL SUPPORT CONTINUED POTENTIAL FOR SUPERCELLS WITH HAIL/DAMAGING WINDS. BACKED LOW-LEVEL WINDS VICINITY DIFFERENTIAL HEATING BOUNDARY IN NRN/NERN NC AND SERN VA WILL BE MAINTAINED GIVEN AREA OF PRESSURE FALLS LOCATED EAST OF WRN NC SURFACE LOW AND SUPPORT GREATEST THREAT FOR TORNADOES. THIS TORNADO THREAT WILL CONTINUE INTO THE EVENING ALONG TRACK OF SURFACE LOW THROUGH MUCH OF NC AND POTENTIALLY SRN VA. ...TX TO GULF COAST STATES... SEVERE STORMS TO CONTINUE ACROSS CENTRAL/SE TX THIS AFTERNOON/ EVENING WITHIN CLUSTER OF STORMS ACROSS THIS REGION. VERY UNSTABLE AIR MASS /MLCAPE UP TO 3000 J/KG/ LOCATED OVER CENTRAL/SRN TX WILL SUPPORT ADDITIONAL SEVERE THUNDERSTORM DEVELOPMENT AS ADDITIONAL SURFACE HEATING WEAKENS INHIBITION AHEAD OF SWD MOVING COLD FRONT/OUTFLOW BOUNDARIES. NEW STORMS SHOULD CONTINUE TO DEVELOP WWD AS WELL INTO SW TX AS HEATING WEAKENS CINH FOR SURFACE BASED STORMS. STRONG DEEP LAYER SHEAR WILL CONTINUE TO SUPPORT SUPERCELLS WITH VERY LARGE HAIL LIKELY GIVEN THE MAGNITUDE OF AVAILABLE INSTABILITY/ STEEP LAPSE RATES. VERY UNSTABLE AIR MASS OVER DEEP S TX IS EXPECTED TO SUPPORT SEVERE POTENTIAL WELL AFTER DARK AS ONGOING ACTIVITY MOVES SWD LATER IN PERIOD. FARTHER E ACROSS LA TO CENTRAL GULF COAST STATES...AIR MASS ACROSS MUCH OF LA HAS BEEN STABILIZED BY EARLIER MCS...BUT AREAS OF SURFACE HEATING EWD ALONG GULF COAST REGION INTO SRN GA/NW FL EXPECTED TO MAINTAIN MODERATELY UNSTABLE AIR MASS. SURFACE FRONT EXTENDED FROM CENTRAL GA SWWD THROUGH SRN AL/MS WITH A WEAK SURFACE TROUGH EXTENDING FROM SRN GA TO THE ERN FL PANHANDLE. STRONG DEEP LAYER SHEAR ACROSS THIS AREA WILL PROMOTE THREAT FOR ORGANIZED STORMS THAT DEVELOP ALONG/S OF SWD MOVING SURFACE BOUNDARIES...WITH HAIL/ DAMAGING WIND GUSTS THE PRIMARY THREATS. ...SRN HIGH PLAINS... DESPITE RATHER DRY SUB-CLOUD LAYER/LOW SURFACE DEWPOINTS ACROSS CENTRAL ROCKIES INTO NRN NM...FORCING FOR LARGE SCALE ASCENT ASSOCIATED WITH SHORT WAVE TROUGH MOVING ESE OVER FOUR CORNERS REGION AND STEEP LAPSE RATES/SURFACE HEATING PROMOTING TSTMS. STRONG DEEP LAYER SHEAR ACROSS NRN NM MAY SUPPORT A SEVERE THREAT INTO THE EVENING...BUT WEAK INSTABILITY SHOULD LIMIT THE COVERAGE. GREATER SEVERE THREAT IS EXPECTED FARTHER S ACROSS SERN NM/SW TX LATER THIS AFTERNOON/EVENING AS WWD TRANSPORT OF LOW-LEVEL MOISTURE CONTINUES WITH ADDITIONAL SURFACE HEATING FURTHER DESTABILIZING THE AIR MASS WITH MLCAPES 1000-2000 J/KG. STRONG DEEP LAYER SHEAR ACROSS THIS REGION WILL SUPPORT SUPERCELLS WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY THREATS. ..PETERS.. 05/14/2006  From swody1 at goshenarc.org Mon May 15 01:01:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 21:01:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150058 SWODY1 SPC AC 150056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT SUN MAY 14 2006 VALID 150100Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM ERN VA/SRN CHESAPEAKE BAY SWD TO SRN GA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CNTRL AND ERN NM SEWD TO S TX... ...ERN VA TO SRN GA... LATEST MESOANALYSIS INDICATED SURFACE LOW OVER CNTRL NC WHICH IS FORECAST TO DEVELOP NWD ALONG BAROCLINIC ZONE TOWARD THE DELMARVA OVERNIGHT. TRAILING COLD FRONT EXTENDING SWWD FROM THIS SURFACE LOW TO THE CNTRL GULF COAST WILL CONTINUE TO PUSH SEWD THROUGH MUCH OF THE SERN U.S. EXCEPT FL. REGIONAL VWPS AND 15/00Z SOUNDINGS INDICATE RELATIVELY STRONG LOW AND DEEP-LAYER SHEAR ACROSS THE PIEDMONT AND COASTAL PLAIN THIS EVENING OWING TO COUPLING OF WSWLY 60-70 KT MID-LEVEL JET STREAK AND 30-40 KT SWLY LLJ. SEVERAL CLUSTERS OF STRONG TO SEVERE STORMS /SOME OF WHICH EXHIBITING SUPERCELL STRUCTURES/ ARE ONGOING FROM VICINITY OF THE SURFACE LOW OVER CNTRL/ERN NC SWD INTO ERN SC AND SRN GA. OBSERVATIONAL DATA INDICATE THAT AIR MASS IS ONLY WEAKLY UNSTABLE WITH MLCAPES OF 500-800 J/KG...HOWEVER THE STRONG VERTICAL SHEAR SHOULD MAINTAIN THE THREAT OF LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES FOR THE NEXT SEVERAL HOURS. ...S TX... SURFACE AND SOUNDING DATA INDICATE THE PRESENCE OF A MOIST...HOT AND STRONGLY UNSTABLE / MLCAPES OF 2000-3000 J/KG / AIR MASS IN PLACE AHEAD OF MCS PROPAGATING SWD THROUGH THE REGION. PRESENCE OF STRONG DIRECTIONAL SHEAR AND RESULTANT 40-50 KTS OF EFFECTIVE SHEAR SHOULD SUPPORT EMBEDDED SUPERCELL STRUCTURES CAPABLE OF LARGE...DAMAGING HAIL AND PERHAPS A COUPLE BRIEF TORNADOES. OTHERWISE...STEEP LOW LEVEL LAPSE RATES AND DCAPES AOA 1500 J/KG SHOULD SUPPORT FURTHER ORGANIZATION OF MCS COLD POOL WITH A CONTINUING THREAT OF DAMAGING WINDS. ...ERN NM INTO FAR WRN AND SWRN TX... TSTMS HAVE DEVELOPED LATE THIS AFTERNOON AND EVENING OVER PARTS OF CNTRL INTO S-CNTRL NM AHEAD OF WEAK IMPULSE MOVING THROUGH ERN AZ. 15/00Z ELP SOUNDING INDICATES THAT THIS ACTIVITY IS DEVELOPING WITHIN A DEEPLY MIXED BOUNDARY-LAYER WITH MLCAPES OF 300-500 J/KG. THE PRESENCE OF STEEP LOW AND MID-LEVEL LAPSE RATES COUPLED WITH MODESTLY STRONG DEEP-LAYER VERTICAL SHEAR /35-45 KTS/ SHOULD SUPPORT A FEW ORGANIZED STORMS CAPABLE OF SOME SEVERE HAIL AND MORE SO LOCALLY DAMAGING WINDS. ONGOING STORMS OVER S-CNTRL NM MAY ATTEMPT TO ORGANIZE A COLD POOL TONIGHT...WITH A THREAT OF DAMAGING WINDS SPREADING SWD INTO FAR WRN TX. OTHER MORE ISOLATED STORMS CAPABLE OF LOCALLY HIGH WINDS AND HAIL WILL BE POSSIBLE ALONG THE HIGHER TERRAIN OF SWRN TX. ..MEAD.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 05:18:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 01:18:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150515 SWODY1 SPC AC 150513 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1213 AM CDT MON MAY 15 2006 VALID 151200Z - 161200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... AMPLIFIED LONG WAVE PATTERN WILL PERSIST THROUGH THE DAY ONE PERIOD...CHARACTERIZED BY TROUGHING IN THE E AND RIDGING IN THE W. MORE SPECIFICALLY...UPPER LOW NOW OVER THE MIDDLE OH VALLEY IS FORECAST TO SHIFT NEWD TOWARD THE MIDDLE ATLANTIC COAST AS VORTICITY MAXIMUM NOW OVER THE MID MS VALLEY ROTATES THROUGH MEAN TROUGH BASE AND THEN NEWD ALONG THE ATLANTIC COAST. MEANWHILE...ANOTHER VORTICITY MAXIMUM OVER THE WRN GREAT LAKES WILL PIVOT SWWD AND THEN SWD INTO THE LOWER MS VALLEY BY TUESDAY MORNING. IN THE W...SHORT WAVE TROUGH NOW OFF THE CNTRL CA COAST WILL LIFT NEWD ALONG THE PACIFIC NW COAST LATER TODAY INTO TONIGHT. IN THE LOW-LEVELS...PRIMARY SURFACE FRONT WILL EXTEND FROM LOW PRESSURE OVER THE DELMARVA SWD ALONG THE CNTRL/SRN ATLANTIC COASTAL PLAIN AND THEN MORE SWWD ACROSS NRN FL. THIS FRONT MAY REMAIN QUASI-STATIONARY OR WILL ONLY SLOWLY SHIFT EWD AND SEWD THROUGH THE DAY...PRIOR TO ACCELERATING TONIGHT WITH THE PASSAGE OF AFOREMENTIONED VORTICITY MAXIMUM AROUND UPPER LOW. ...SRN GA/FL... CONVERGENCE ALONG FRONT COUPLED WITH INCREASED FORCING FOR ASCENT AHEAD OF APPROACHING VORTICITY MAXIMUM ARE EXPECTED TO CONTRIBUTE TO AN INCREASE IN STORM COVERAGE AND INTENSITY BY AFTERNOON ACROSS NRN FL AND SRN GA. RELATIVELY WEAK MID-LEVEL LAPSE RATES SHOULD TEND TO LIMIT DESTABILIZATION PROCESS WITH MLCAPES OF 500-1000 J/KG. HOWEVER...RATHER STRONG VERTICAL SPEED SHEAR MAY SUPPORT A FEW ORGANIZED STORMS CAPABLE OF LOCALLY STRONG WIND GUSTS AND SOME SEVERE HAIL. THIS ISOLATED SEVERE THREAT IS EXPECTED TO DEVELOP SWD ALONG ERN FL SEA BREEZE BOUNDARY THIS AFTERNOON AS LOW-LEVEL CONVERGENCE IS ENHANCED BY THE AMBIENT WSWLY LOW-LEVEL FLOW. IN ADDITION TO ISOLATED HIGH WINDS/HAIL...A BRIEF TORNADO OR TWO WILL BE POSSIBLE WITH THE MORE INTENSE STORMS. ...ERN AZ/WRN NM... OROGRAPHIC FORCING COUPLED WITH LOW-LEVEL MASS CONVERGENCE ALONG WRN EXTENSION OF LOW-LEVEL BAROCLINIC ZONE ARE EXPECTED TO PROVIDE A FOCUS FOR DIURNAL TSTM DEVELOPMENT THIS AFTERNOON INTO EVENING. THE COMBINATION OF RELATIVELY STEEP LOW AND MID-LEVEL LAPSE RATES...STRONG LOW-LEVEL HODOGRAPH CURVATURE AND MODEST DEEP-LAYER SHEAR SHOULD SUPPORT A FEW ORGANIZED STORMS CAPABLE OF LOCALLY STRONG DOWNDRAFTS AND MARGINALLY SEVERE HAIL. ...PACIFIC NW... ISOLATED TO SCATTERED TSTM DEVELOPMENT WILL BE POSSIBLE ALONG THE CASCADES THIS AFTERNOON INTO TONIGHT IN ASSOCIATION WITH IMPULSE SHIFTING NNEWD ALONG THE PACIFIC COAST. HOWEVER...NAM BOUNDARY-LAYER MOISTURE FORECASTS ARE TOO HIGH WHICH IS RESULTING IN EXCESSIVE INSTABILITY. NO SEVERE WEATHER IS FORECAST. ..MEAD/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 12:51:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 08:51:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151248 SWODY1 SPC AC 151245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT MON MAY 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE EASTERN FL PENINSULA... ...EASTERN FL PENINSULA... PERSISTENT UPPER LOW OVER THE EASTERN STATES WILL REMAIN IN PLACE THROUGH TODAY...WITH MAIN SURFACE BAROCLINIC ZONE STRETCHING ACROSS SOUTHERN GA/NORTH FL AND ALONG THE CAROLINA COAST. AIR MASS ALONG AND SOUTH OF FRONT WILL BE MOIST AND MODERATELY UNSTABLE WITH AFTERNOON MLCAPE VALUES OVER 1500 J/KG. DEEP WESTERLY FLOW ACROSS THE FL PENINSULA SHOULD LIMIT INLAND PROGRESS OF EAST COAST SEA BREEZE...PROVIDING A FOCUS FOR AFTERNOON THUNDERSTORM DEVELOPMENT ALONG THE IMMEDIATE COAST. FAVORABLE DEEP LAYER VERTICAL SHEAR WILL BE PRESENT FOR UPDRAFT ROTATION AND THE POSSIBILITY OF HAIL/DAMAGING WINDS IN STRONGER CELLS. AN ISOLATED TORNADO ALSO CANNOT BE RULED OUT DUE TO BOUNDARY INTERACTIONS. ACTIVITY SHOULD DIMINISH IN INTENSITY SHORTLY AFTER 00Z. ...AZ/NM... WESTERN PERIPHERY OF NORTHERN MID LEVEL WINDS EXTENDS ALONG THE ROCKIES INTO EASTERN AZ/WESTERN NM. SUFFICIENT LOW/MID LEVEL MOISTURE AND STEEP LAPSE RATES WILL LIKELY BE PRESENT IN THIS REGION FOR SCATTERED AFTERNOON/EVENING THUNDERSTORMS. DESPITE WEAK VERTICAL SHEAR...ISOLATED STRONG CELLS CAPABLE OF GUSTY WINDS AND HAIL ARE POSSIBLE. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED IN THIS REGION TODAY. ...EASTERN NC... MORNING CLOUDINESS OVER EASTERN NC WILL LIKELY ERODE THIS AFTERNOON...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE AHEAD OF SURFACE COLD FRONT. SCATTERED THUNDERSTORMS MAY DEVELOP AFTER 18Z OVER EASTERN NC...MOVING OFFSHORE BEFORE 00Z. THIS REGION WILL BE BENEATH 70 KNOT MID LEVEL JET MAX...WITH MORE THAN SUFFICIENT VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS. AREAL COVERAGE MAY BE LIMITED...BUT GUSTY WINDS AND HAIL ARE POSSIBLE FROM ANY SUSTAINED STORM IN THIS REGION TODAY. ..HART/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 12:51:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 08:51:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151248 SWODY1 SPC AC 151245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT MON MAY 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE EASTERN FL PENINSULA... ...EASTERN FL PENINSULA... PERSISTENT UPPER LOW OVER THE EASTERN STATES WILL REMAIN IN PLACE THROUGH TODAY...WITH MAIN SURFACE BAROCLINIC ZONE STRETCHING ACROSS SOUTHERN GA/NORTH FL AND ALONG THE CAROLINA COAST. AIR MASS ALONG AND SOUTH OF FRONT WILL BE MOIST AND MODERATELY UNSTABLE WITH AFTERNOON MLCAPE VALUES OVER 1500 J/KG. DEEP WESTERLY FLOW ACROSS THE FL PENINSULA SHOULD LIMIT INLAND PROGRESS OF EAST COAST SEA BREEZE...PROVIDING A FOCUS FOR AFTERNOON THUNDERSTORM DEVELOPMENT ALONG THE IMMEDIATE COAST. FAVORABLE DEEP LAYER VERTICAL SHEAR WILL BE PRESENT FOR UPDRAFT ROTATION AND THE POSSIBILITY OF HAIL/DAMAGING WINDS IN STRONGER CELLS. AN ISOLATED TORNADO ALSO CANNOT BE RULED OUT DUE TO BOUNDARY INTERACTIONS. ACTIVITY SHOULD DIMINISH IN INTENSITY SHORTLY AFTER 00Z. ...AZ/NM... WESTERN PERIPHERY OF NORTHERN MID LEVEL WINDS EXTENDS ALONG THE ROCKIES INTO EASTERN AZ/WESTERN NM. SUFFICIENT LOW/MID LEVEL MOISTURE AND STEEP LAPSE RATES WILL LIKELY BE PRESENT IN THIS REGION FOR SCATTERED AFTERNOON/EVENING THUNDERSTORMS. DESPITE WEAK VERTICAL SHEAR...ISOLATED STRONG CELLS CAPABLE OF GUSTY WINDS AND HAIL ARE POSSIBLE. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED IN THIS REGION TODAY. ...EASTERN NC... MORNING CLOUDINESS OVER EASTERN NC WILL LIKELY ERODE THIS AFTERNOON...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE AHEAD OF SURFACE COLD FRONT. SCATTERED THUNDERSTORMS MAY DEVELOP AFTER 18Z OVER EASTERN NC...MOVING OFFSHORE BEFORE 00Z. THIS REGION WILL BE BENEATH 70 KNOT MID LEVEL JET MAX...WITH MORE THAN SUFFICIENT VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS. AREAL COVERAGE MAY BE LIMITED...BUT GUSTY WINDS AND HAIL ARE POSSIBLE FROM ANY SUSTAINED STORM IN THIS REGION TODAY. ..HART/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 16:33:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 12:33:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151630 SWODY1 SPC AC 151628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT MON MAY 15 2006 VALID 151630Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF FL PENINSULA... ...THERE IS A SLGT RISK OF SVR TSTMS EASTERN NORTH CAROLINA... ...FL/SERN GA... WITH UPPER LOW SLOWLY MOVING EWD THRU OH VALLEY...MDT/STG WESTERLIES REMAIN SERN U.S. FRONTAL ZONE EXTENDS FROM ERN NC SWWD THRU SRN GA TO OFFSHORE MOBILE BAY. WITH STRONG HEATING AND INCREASING LOW LEVEL MOISTURE...AIR MASS S OF FRONT IS BECOMING MODERATELY UNSTABLE WITH MLCAPES TO 1500 J/KG OVER MUCH OF FL PENINSULA THIS AFTERNOON. GREATEST INSTABILITY WILL BE S FL WHERE DEWPOINTS AROUND 70F COUPLED WITH TEMPERATURES TO NEAR 90F RESULT IN MLCAPES TO 2500 J/KG. WITH 30-40KT OF DEEP LAYER SHEAR TYPICAL ACROSS FL THIS AFTERNOON...STORMS THAT ARE ABLE TO DEVELOP WILL HAVE SEVERE POTENTIAL. WLY COMPONENT WILL HOLD E COAST SEA BREEZE TO JUST INLAND WHICH WILL FOCUS BEST AREA OF STORM INITIATION BY MID AFTERNOON ERN FL PENINSULA. PRIMARY THREAT WILL BE LARGE HAIL GIVEN THE RELATIVELY STEEP LAPSE RATES OF 7C/KM...HOWEVER ISOLATED WIND DAMAGE/TORNADOES ARE ALSO POSSIBLE WHERE LOCALLY SURFACE CONVERGENCE IS ENHANCED ALONG SEA BREEZE FRONT AND CONVECTIVE BOUNDARIES. STORMS SHOULD WEAKEN/MOVE OFFSHORE BY 00Z ENDING SEVERE THREAT. ...NC COAST... SUFFICIENT LOW LEVEL MOISTURE EXPECTED TO REMAIN COASTAL COUNTIES THRU THE AFTERNOON TO MAINTAIN POTENTIAL FOR ISOLATED SEVERE THUNDERSTORM DEVELOPMENT. STRONG DEEP LAYER SHEAR AS 70KT MID LEVEL JET ROTATES ACROSS ERN CAROLINAS TO SUPPORT POTENTIAL FOR ROTATION OF STRONGEST STORMS. AGAIN THE STEEP LAPSE RATES AND RELATIVELY COOL AIR AT MID LEVELS WILL RESULT IN POSSIBLE SEVERE HAIL AND BRIEF DAMAGING WIND GUSTS THRU THE AFTERNOON. AS A RESULT HAVE UPGRADED THIS AREA TO A SLIGHT RISK. ...ERN AZ/WRN NM... SURFACE RIDGE PLAIN STATES WILL MAINTAIN ELY LOW LEVEL FLOW WRN NM INTO ERN AZ. MOISTURE ACCORDINGLY HAS SPREAD AS FAR W AS MOGOLLON RIM SWD IN AZ. THE STRONG HEATING AND STEEP LAPSE RATES IN PLACE ACROSS AZ COUPLED WITH INFLUX OF MOISTURE EXPECTED TO DEVELOP RELATIVELY HIGH BASED THUNDERSTORMS BY MID AFTERNOON OVER HIGHER TERRAIN OF ERN AZ/WRN NM. GUSTY WINDS WILL BE ASSOCIATED WITH THESE STORMS...PARTICULARLY AS THEY PROPAGATE INTO ADJACENT DESERTS VALLEYS BY LATE AFTERNOON. ..HALES/GRAMS.. 05/15/2006  From swody1 at goshenarc.org Tue May 16 00:44:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 20:44:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160041 SWODY1 SPC AC 160039 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 PM CDT MON MAY 15 2006 VALID 160100Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM FAR SERN VA INTO SERN GA/NRN FL... ...ERN NC TO ERN GA... WATER VAPOR IMAGERY AND PLAN VIEW PROFILER/VWP DATA INDICATE A SHORT WAVE TROUGH AND ASSOCIATED 70 KT MID-LEVEL JET STREAK ROTATING NEWD THROUGH MEAN LONG WAVE TROUGH BASE INTO THE SERN STATES THIS EVENING. DEEP-LAYER FORCING FOR ASCENT IN LEFT EXIT REGION OF THIS JET STREAK HAS MAINTAINED A SURFACE LOW OVER E-CNTRL NC...WHICH IS FORECAST TO DEVELOP NEWD ALONG THE MIDDLE ATLANTIC COAST OVERNIGHT. AS A RESULT...COLD FRONT HAS EFFECTIVELY STALLED ACROSS S-CNTRL NC/N-CNTRL SC...WITH SOME EWD MOVEMENT NOTED FARTHER TO THE S OVER ERN GA. DESPITE RELATIVELY WEAK INSTABILITY OBSERVED ON THE 16/00Z MHX/CHS SOUNDINGS / I.E. SBCAPE OF 500-800 J/KG / AND THE ONSET OF NOCTURNAL COOLING...STRONG DEEP-LAYER SPEED SHEAR AND INCREASED DYNAMIC FORCING SHOULD MAINTAIN AN ENVIRONMENT SUPPORTIVE OF SEVERE STORMS FOR THE NEXT FEW HOURS FROM NERN SC INTO FAR SERN VA. WHILE LOCALLY DAMAGING WINDS AND SEVERE HAIL WILL BE THE PRIMARY SEVERE THREATS...A BRIEF TORNADO OR TWO WILL BE POSSIBLE WITH ANY EMBEDDED SUPERCELL STRUCTURES. FARTHER S...ISOLATED SEVERE STORMS WILL REMAIN POSSIBLE OVERNIGHT ALONG COLD FRONT MOVING THROUGH NRN FL...AS WELL AS WITH ANY CONVECTIVE CLUSTERS MOVING ONTO THE FL PENINSULA FROM THE ERN GULF OF MEXICO. ...SWRN NM... CLUSTERS OF TSTMS HAVE DEVELOPED LATE THIS AFTERNOON AND EARLY EVENING OVER PORTIONS OF W-CNTRL INTO SWRN NM...PERHAPS IN ASSOCIATION WITH A WEAK IMPULSE SHIFTING SEWD FROM THE 4-CORNERS REGION. 16/00Z ELP SOUNDING INDICATED THE PRESENCE OF STEEP LOW AND MID-LEVEL LAPSE RATES WHICH WERE CONTRIBUTING TO WEAK CONVECTIVE INSTABILITY WITH SBCAPES OF 200-300 J/KG. GIVEN THE STEEP LAPSE RATES AND DEEPLY MIXED BOUNDARY LAYER...SOME THREAT WILL EXIST FOR ISOLATED STRONG WIND GUSTS AND/OR SEVERE HAIL THROUGH THE REMAINDER OF THE EVENING. ..MEAD.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 05:57:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 01:57:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160554 SWODY1 SPC AC 160552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1252 AM CDT TUE MAY 16 2006 VALID 161200Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN FL PENINSULA... ...SYNOPSIS... AMPLIFIED LARGE-SCALE PATTERN WILL CONTINUE THROUGH THE DAY ONE PERIOD WITH LONG WAVE TROUGHING IN THE E AND A RIDGE INTO THE W. UPPER LOW NOW OVER THE CNTRL APPALACHIANS WILL LIFT NEWD TOWARD THE ST. LAWRENCE VALLEY WITH LONG WAVE TROUGH BECOMING MORE ELONGATED AS SHORT WAVE TROUGH DIGS SEWD ACROSS THE NRN GULF OF MEXICO. SEVERAL OTHER WEAK PERTURBATIONS ARE FORECAST TO ROTATE THROUGH THE LARGER-SCALE TROUGH FROM THE GREAT LAKES THROUGH THE MS RIVER VALLEY. IN THE LOW-LEVELS...SURFACE CYCLONE ATTENDANT TO UPPER LOW WILL DEVELOP NEWD THROUGH ERN NEW ENGLAND INTO THE ST. LAWRENCE VALLEY. TRAILING COLD FRONT WILL CONTINUE TO PUSH EWD INTO THE ATLANTIC WITH SWRN EXTENSION SLOWLY SAGGING SWD THROUGH THE CNTRL AND SRN FL PENINSULA. AN ADDITIONAL COLD FRONTAL SURGE IS FORECAST TO MOVE SWD THROUGH THE MID MS/LOWER OH VALLEYS SWD THROUGH THE MID SOUTH AND TN/LOWER MS VALLEYS. ...S FL... REGIONAL RADAR AND LIGHTNING DATA INDICATE ACTIVE CONVECTION ACROSS THE CNTRL AND ERN GULF BASIN...SUGGESTING THAT STORMS WILL LIKELY BE ONGOING AT 16/12Z WITHIN PRE-FRONTAL AIR MASS OVER THE CNTRL/SRN PENINSULA. LARGE-SCALE FORCING AHEAD OF MCV SHIFTING EWD THROUGH THE CNTRL GULF COUPLED WITH HEIGHT FALLS ASSOCIATED WITH SHORT WAVE TROUGH DIVING SEWD TOWARD THE NRN GULF SHOULD MAINTAIN CLUSTERS OF TSTMS THROUGH THE FORECAST PERIOD ALONG AND S OF FRONTAL ZONE. CONSIDERABLE CLOUDS AND PRECIPITATION WILL TEND TO LIMIT DESTABILIZATION...THOUGH THE PRESENCE OF A MOIST LOW-LEVEL AIR MASS /I.E. DEWPOINTS IN THE 60S TO LOWER 70S/ SHOULD CONTRIBUTE TO MLCAPES OF AROUND 1000 J/KG. MODESTLY STRONG DEEP-LAYER SPEED SHEAR WILL BE SUPPORTIVE OF A FEW SEVERE STORMS CAPABLE OF MAINLY LARGE HAIL AND DAMAGING WINDS. BEST POTENTIAL FOR SUPERCELLS AND A COUPLE OF TORNADOES WILL EXIST AHEAD OF SURFACE LOW WHICH IS FORECAST TO SHIFT EWD ACROSS THE SRN PENINSULA THIS EVENING OWING TO LOCALLY ENHANCED LOW-LEVEL SHEAR. ...MID SOUTH INTO LOWER MS VALLEY... COLD MID-LEVEL TEMPERATURES /I.E. -20 C AT 500 MB/ COUPLED WITH DIABATIC HEATING ARE EXPECTED TO CONTRIBUTE TO THE DEVELOPMENT OF STEEP LOW TO MID-LEVEL LAPSE RATES AND WEAK CONVECTIVE INSTABILITY AHEAD OF SECONDARY FRONTAL SURGE THIS AFTERNOON. A FEW OF THE STRONGER STORMS WILL BE CAPABLE OF HAIL /SOME APPROACHING SEVERE LEVELS/ AND GUSTY WINDS INTO THE EVENING HOURS. ...MIDWEST... A SECONDARY REGION OF TSTMS WILL BE POSSIBLE TODAY AHEAD OF VORTICITY LOBE ROTATING SEWD OUT OF THE GREAT LAKES. IT APPEARS THAT CLOUD COVER WILL BE MORE WIDESPREAD THAN POINTS TO THE S...EFFECTIVELY LIMITING LAPSE RATES AND RESULTANT DEGREE OF DESTABILIZATION. NONETHELESS...SOME SMALL HAIL WILL BE POSSIBLE WITH THE MORE INTENSE STORMS. ...ERN NEW ENGLAND... DEEP-LAYER FORCING WILL INCREASE ACROSS THE REGION TODAY WITH APPROACH OF SURFACE AND UPPER-LEVEL LOWS. TSTMS ARE EXPECTED TO BECOME INCREASINGLY LIKELY BY AFTERNOON FROM VICINITY OF LOW SWD ALONG COLD FRONT. CURRENTLY...IT APPEARS THAT INSTABILITY WILL REMAIN QUITE WEAK...THOUGH THE STRONG FORCING FOR ASCENT AND INCREASING VERTICAL SHEAR MAY SUPPORT A FEW VIGOROUS STORMS CAPABLE OF GUSTY WINDS AND SMALL HAIL. ..MEAD/TAYLOR.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 12:31:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 08:31:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161228 SWODY1 SPC AC 161227 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0727 AM CDT TUE MAY 16 2006 VALID 161300Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN FL PENINSULA... ...FL... UPPER TROUGH WILL REMAIN OVER THE EASTERN STATES TODAY...ALTHOUGH PRIMARY UPPER LOW CENTER WILL BEGIN SHIFTING NORTHEASTWARD INTO NEW ENGLAND. MORNING SATELLITE AND RADAR IMAGERY SHOW WIDESPREAD CONVECTION OVER THE EASTERN GULF OF MEXICO AND THE FL PENINSULA. THIS ACTIVITY WILL LIKELY CONTINUE TO AFFECT FL FOR MUCH OF THE DAY. LOW AND MID LEVEL WINDS STRENGTHEN SLIGHTLY DURING THE DAY...MAINTAINING VERTICAL SHEAR PARAMETERS FAVORABLE FOR ORGANIZED AND ISOLATED SEVERE STORMS. THE MAIN FORECAST QUESTION INVOLVES THE AMOUNT OF INSTABILITY THAT WILL DEVELOP ACROSS THIS REGION TODAY. WIDESPREAD CLOUDINESS AND SCATTERED PRECIP WILL LIMIT DIURNAL HEATING...WITH POCKETS OF AFTERNOON MLCAPE VALUES AROUND 1500 J/KG. ISOLATED STORMS IN THIS REGION WILL BE CAPABLE OF WET MICROBURSTS AND HAIL. ...MS/TN VALLEY... LATEST WATER VAPOR IMAGERY SHOWS WELL-DEFINED UPPER SHORTWAVE TROUGH ROTATING AROUND UPPER LOW ACROSS IL/MO. THIS FEATURE IS EXPECTED TO MOVE SOUTHWARD INTO THE TN AND MIDDLE MS VALLEYS BY THIS AFTERNOON. COOL MID LEVEL TEMPERATURES AND RELATIVELY STEEP LOW/MID LEVEL LAPSE RATES WILL HELP DESTABILIZE AIR MASS...ALTHOUGH SURFACE DEWPOINTS ARE LIKELY TO REMAIN BELOW 50F. AFTERNOON CAPE VALUES OF UP TO 1000 J/KG WILL AID IN THE DEVELOPMENT OF ISOLATED TO SCATTERED THUNDERSTORMS. THERMODYNAMIC PROFILES SUGGEST HAIL WILL BE POSSIBLE IN STRONGER CELLS. ORGANIZED SEVERE STORMS DO NOT APPEAR LIKELY AT THIS TIME. ..HART/TAYLOR.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 16:11:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 12:11:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161602 SWODY1 SPC AC 161601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1101 AM CDT TUE MAY 16 2006 VALID 161630Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS SOUTHERN FL... ...SRN FL... LARGE TROUGH IN E AND RIDGE IN THE W WITH UNSEASONABLY STRONG WESTERLIES ACROSS FL PENINSULA. COLD FRONTAL ZONE CENTRAL FL IS MOVING ONLY VERY SLOWLY SWD. SATELLITE AND RADAR INDICATE EXTENSIVE CLOUDINESS AND CONVECTION CONTINUING EXTREME S FL SWD TO WRN CUBA AHEAD OF A WEAK S/WV TROUGH CURRENTLY CENTRAL GULF OF MEXICO. WHILE DEEP LAYER SHEAR REMAINS SUPPORTIVE OF ORGANIZED THUNDERSTORMS S FL TO S OF COLD FRONT...THE SEVERE THREAT WILL BE DEPENDENT ON AMOUNT OF INSTABILITY THAT CAN DEVELOP THIS AFTERNOON. HIGHER THREAT FOR SEVERE STORMS APPEARS TO BE PRIMARILY ERN PORTION OF S FL WHERE INSTABILITY AND LOW LEVEL MOISTURE IS GREATEST. MLCAPES COULD CLIMB TO NEAR 2000 J/KG SE COASTAL AREA WHICH COUPLED WITH CONVERGENCE ALONG THE SEA BREEZE FRONT WOULD ENHANCE POTENTIAL FOR SEVERE STORMS BY MID AFTERNOON. ADDITIONALLY DEEPER TROPICAL MOISTURE ACROSS KEYS WILL CONTINUE TO SUPPORT PRIMARILY MULTICELL STORMS ALONG WITH DAMAGING WIND POTENTIAL. ...MS/TN VALLEY REGION... S/WV IMPULSE ROTATING SWD THRU LOWER MO VALLEY AROUND ERN U.S. TROUGH WILL AID IN CONVECTIVE DEVELOPMENT THIS AFTERNOON. HEATING AND STEEP LOW/MID LEVEL LAPSE RATES WILL DESTABILIZE AIR MASS TN VALLEY AREA WWD TO MS VALLEY. THUNDERSTORMS WILL INCREASE THRU THE AFTERNOON WITH HEATING...HOWEVER THE RELATIVE WEAK SHEAR WILL LIMIT SEVERE THREAT TO A FEW HAIL EVENTS. ..HALES/CARBIN.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 19:58:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 15:58:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161953 SWODY1 SPC AC 161952 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0252 PM CDT TUE MAY 16 2006 VALID 162000Z - 171200Z ...NO SVR TSTM AREAS FORECAST... ...LOWER MS/TN VALLEYS... COLDEST MID LEVEL TEMPERATURES ARE SETTLING INTO THE BASE OF THE TROUGH OVER THE LOWER MS VALLEY WHERE H5 READINGS ARE ROUGHLY -20C. RESULTANT THERMODYNAMIC PROFILES ARE QUITE STEEP GIVEN STRONG BOUNDARY LAYER HEATING...LOWEST 3KM LAPSE RATES ON THE ORDER OF 8-8.5C/KM FROM MIDDLE TN...SWWD INTO NRN LA. NUMEROUS SHOWERS AND THUNDERSTORMS HAVE DEVELOPED BENEATH THIS COLD POCKET...IMMEDIATELY AHEAD OF UPPER VORT ROTATING SEWD ACROSS MO...WHERE INCREASING NWLY FLOW IS SUFFICIENTLY STRONG ENOUGH TO MAINTAIN MOVEMENT OF PULSE-MULTI CELL UPDRAFTS. FORECAST SOUNDINGS ACROSS THE LOWER MS/TN VALLEYS SUGGEST SOME HAIL WILL DEVELOP WITHIN THE STRONGEST UPDRAFTS BUT MUCH OF THIS ACTIVITY SHOULD REMAIN AOB ORGANIZED SEVERE LEVELS. ...IA... LATEST WV IMAGERY DEPICTS A FAIRLY WELL DEFINED UPPER VORT ALONG THE IL/IA BORDER...ROTATING SSWWD ALONG THE MS RIVER. THIS FEATURE APPEARS PARTLY RESPONSIBLE FOR RECENT INCREASE IN CONVECTION FROM NEAR LSE TO OTM. SUFFICIENT INSTABILITY EXISTS ACROSS THIS REGION FOR MARGINALLY SEVERE HAIL WITH THE STRONGEST UPDRAFTS THROUGH EARLY EVENING. ...SWRN U.S... CONSIDERABLE AMOUNT OF CONVECTION HAS RECENTLY DEVELOPED WITHIN MOIST HIGH LEVEL DEFORMATION ZONE FROM NWRN AZ INTO SWRN NM. STRONG HEATING OVER THE HIGHER TERRAIN HAS CERTAINLY AIDED RECENT UPDRAFT DEVELOPMENT WHICH APPEARS TO BE DRIFTING SWWD TOWARD THE LOWER ELEVATIONS. MUCH OF THIS ACTIVITY SHOULD HOWEVER STRUGGLE TO GENERATE SIGNIFICANT PRECIPITATION WHICH MAY ULTIMATELY LIMIT STRONGEST STORMS TO BRIEF BOUTS OF GUSTY WINDS OR SOME HAIL. ..DARROW.. 05/16/2006  From swody1 at goshenarc.org Wed May 17 01:02:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 21:02:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170058 SWODY1 SPC AC 170056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT TUE MAY 16 2006 VALID 170100Z - 171200Z ...NO SVR TSTM AREAS FORECAST... ...SIERRA NEVADAS... MOST VIGOROUS CONVECTION AS OF 0030Z WAS OCCURRING NW OF RNO ALONG WRN EDGE OF MID-LEVEL MOISTURE PLUME PER WATER VAPOR IMAGERY. THIS MOISTURE COUPLED WITH A DEEP AND WELL-MIXED BOUNDARY LAYER WAS CONTRIBUTING TO SBCAPES OF AROUND 600 J/KG BASED ON 17/00Z RNO SOUNDING. SOME MARGINALLY SEVERE HAIL AND/OR LOCALLY STRONG WIND GUSTS WILL BE POSSIBLE THROUGH 03Z GIVEN THE RELATIVELY STEEP LOW AND MID-LEVEL LAPSE RATES AND STRONG EVAPORATIVE COOLING POTENTIAL IN THE SUB-CLOUD LAYER. ...AZ... REGIONAL RADAR IMAGERY INDICATES THAT TSTMS WHICH DEVELOPED EARLIER THIS AFTERNOON ALONG THE MOGOLLON RIM HAVE RECENTLY WEAKENED WITH A CONVECTIVE OUTFLOW BOUNDARY PUSHING SEWD INTO THE LOWER DESERT FLOOR. 17/00Z TUS SOUNDING INDICATED A DEEPLY MIXED AND QUITE DRY BOUNDARY LAYER WITH MARGINAL CONVECTIVE INSTABILITY. SOME POTENTIAL FOR STORM RE-DEVELOPMENT WILL EXIST ALONG THIS BOUNDARY INTO THE EVENING WITH LOCALLY GUSTY WINDS POSSIBLE. ...TN/MS/AL... LOW TOPPED CONVECTIVE LINE IS IN PROGRESS THIS EVENING ALONG PRESSURE TROUGH/WEAK COLD FRONT FROM W OF CSV TO N OF GWO WITHIN ENVIRONMENT OF MODEST LAPSE RATES AND WEAK INSTABILITY. FORCING FOR ASCENT AHEAD OF VORTICITY MAXIMUM TRANSLATING SEWD INTO THE CNTRL GULF STATES SHOULD MAINTAIN AT LEAST SOME OF THIS ACTIVE CONVECTION FOR THE NEXT SEVERAL HOURS. THE LOSS OF DAYTIME HEATING AND FURTHER WEAKENING OF ALREADY MARGINAL INSTABILITY SHOULD PRECLUDE ANY SEVERE THREAT...THOUGH GUSTY WINDS AND SMALL HAIL WILL REMAIN POSSIBLE WITH THE STRONGEST STORMS. ...MIDWEST... A COUPLE OF N-S ORIENTED TSTM BANDS ARE OCCURRING THIS EVENING FROM ERN IA INTO CNTRL MO AND FROM SRN WI INTO WRN AND CNTRL PARTS OF IL AHEAD OF MID-LEVEL IMPULSE DIVING SWD THROUGH THE REGION. HERE TOO...17/00Z SOUNDINGS INDICATED MODEST LAPSE RATES AND WEAK INSTABILITY WHICH WILL SUPPORT ONGOING STORMS INTO THE EVENING. SMALL HAIL AND LOCALLY GUSTY WINDS WILL REMAIN POSSIBLE FOR THE NEXT FEW HOURS....PRIOR TO STORMS WEAKENING WITH THE ONSET OF NOCTURNAL COOLING. ..MEAD.. 05/17/2006  From swody1 at goshenarc.org Fri May 19 05:41:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 01:41:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190539 SWODY1 SPC AC 190537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1237 AM CDT FRI MAY 19 2006 VALID 191200Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS OZARKS REGION TO TN VALLEY.... ...SYNOPSIS... VERY STABLE LARGE SCALE PATTERN WILL FEATURE SYNOPTIC RIDGE OVER WRN NORTH AMERICA AND TROUGH IN ERN PORTIONS CONUS/CANADA. SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN SASK -- SHOULD AMPLIFY AND DIG SEWD WHILE LEAVING MEAN RIDGE POSITION. AS THIS OCCURS...PRONOUNCED MIDDLE-UPPER LEVEL LOW PRESENTLY OVER LE REGION IS FCST TO MOVE EWD THEN NNEWD ACROSS NY AND SRN QUE. WEAK PERTURBATION OVER NRN HIGH PLAINS IS FCST TO MOVE SEWD ACROSS CENTRAL PLAINS AND OZARKS. ASSOCIATED FRONTAL-WAVE LOW -- NOW WEAKLY EVIDENT OVER ND -- IS EXPECTED TO STRENGTHEN SOMEWHAT AS IT PROPAGATES SEWD ALONG CURRENTLY QUASISTATIONARY BAROCLINIC ZONE. THIS LOW SHOULD CROSS OZARKS REGION DURING LATE AFTERNOON/EARLY EVENING. ...OZARKS REGION TO TN VALLEY... WEAKENING CINH AND LIFT NEAR FRONT WILL SUPPORT TSTM DEVELOPMENT DURING AFTERNOON...SHIFTING SEWD AND PERHAPS EXPANDING IN COVERAGE THROUGH LATE EVENING BEFORE DIMINISHING. DAMAGING GUSTS AND LARGE HAIL ARE ANTICIPATED. TORNADO POTENTIAL IS MORE MRGL...UNCERTAIN AND STRONGLY CONDITIONAL ON MESOSCALE TO STORM SCALE PROCESSES. ETA INITIALIZED TOO HIGH ON SFC MOISTURE IN THIS AREA AND UPSTREAM...AND ITS PROGGED DEW POINT AND CAPE VALUES APPEAR TOO LARGE. HOWEVER...WITH EVAPOTRANSPIRATIVE SUPPORT...SFC DEW POINTS MAINLY FROM UPPER 50S TO MID 60S F ARE POSSIBLE ACROSS THIS AREA...PER WRF SOUNDINGS. LOW-MIDLEVEL LAPSE RATES SHOULD BE STEEPEST OVER MO/AR AT 8-9 DEG C/KM...WEAKENING WITH SEWD EXTENT ALONG FRONTAL ZONE. THIS COMBINED WITH DIABATIC HEATING WILL SUPPORT AFTERNOON MLCAPES NEAR 3000 J/KG...ALSO DIMINISHING WITH SEWD EXTENT...BUT SUPPORTING SEVERE POTENTIAL THROUGH NEAR-FRONTAL CORRIDOR FROM OZARKS SEWD ACROSS WRN/MID TN GIVEN FAVORABLE VERTICAL SHEAR PROFILES EXPECTED. SFC WINDS SHOULD RANGE FROM SWLY IN WARM SECTOR TO LIGHT/VARIABLE IN FRONTAL ZONE...AND PERHAPS SLY-SELY JUST SE OF SFC LOW. THIS WILL SUPPORT LARGE VARIATION IN LOW LEVEL SHEAR PROFILES...WITH 0-3 KM SRH 100-400 J/KG WHERE THERE IS SFC-BASED BUOYANCY...AND EFFECTIVE BULK VALUES 35-55 KT OVER MUCH OF OUTLOOK AREA. SOME SUPERCELLS AND BOW ECHOES ARE POSSIBLE. ...ERN NJ TO SRN/CENTRAL NEW ENGLAND AREA... AIR MASS MAY HEAT/RECOVER SUFFICIENTLY AFTER MORNING CLOUDS/PRECIP TO PERMIT ADDITIONAL TSTMS DURING AFTERNOON...SOME OF WHICH MAY PRODUCE HAIL. AS MID/UPPER LEVEL LOW APCHS...MIDLEVEL ASCENT/COOLING SHOULD CONTRIBUTE TO STEEPENED LAPSE RATES. CINH SHOULD BE SMALL...REQUIRING ONLY WEAK SFC HEATING TO CONVECT IN FCST SOUNDINGS WITH MLCAPES UP TO ABOUT 500 J/KG. UNCERTAINTIES ABOUT SPEED/STRENGTH OF DIURNAL DESTABILIZATION PRECLUDE CATEGORICAL OUTLOOK ATTM. STRONG-SVR TSTM POTENTIAL SHOULD DIMINISH MARKEDLY WITH LOSS OF AFTERNOON INSOLATION. ...NWRN CONUS... WIDELY SCATTERED AFTERNOON TSTMS AGAIN ARE EXPECTED TO FORM...INITIALLY OVER HEATED HIGHER TERRAIN WITH DEVELOPMENT/PROPAGATION INTO VALLEYS AND BASINS. STRONGEST SFC HEATING/MIXING AND AT LEAST MRGLLY FAVORABLE SFC MOISTURE IS EXPECTED OVER THIS AREA...AIDED BY EVAPOTRANSPIRATION OF SOME PRECIP THAT FELL ON THURSDAY. LOW-MIDLEVEL LAPSE RATES APCHG DRY ADIABATIC WILL FURTHER CONTRIBUTE TO MLCAPES GENERALLY 300-800 J/KG. ..EDWARDS.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 12:58:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 08:58:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191254 SWODY1 SPC AC 191253 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 AM CDT FRI MAY 19 2006 VALID 191300Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LWR MO VLY INTO THE TN VLY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER INTERIOR PARTS OF THE PAC NW... ...SYNOPSIS... AMPLIFIED PATTERN WILL CONTINUE OVER THE LWR 48 THIS PERIOD...WITH A RIDGE OVER THE WRN SLOPES OF THE RCKYS AND A TROUGH FROM WRN HUDSON BAY TO THE MID ATLANTIC CST. LEAD IMPULSE ASSOCIATED WITH E PACIFIC TROUGH...NOW OFF THE NRN CA CST...SHOULD EJECT NNE INTO THE LWR COLUMBIA BASIN BY 12Z SATURDAY AS UPSTREAM DISTURBANCE NOW NEAR 40N/135W DROPS SSE TO REPLACE IT. FARTHER E...SHORTWAVE IMPULSES ARE SOMEWHAT HARDER TO DISCERN IN THE NW FLOW ACROSS THE PLAINS. SATELLITE SUGGESTS THAT ONE DISTURBANCE ATTM IS OVER NW MO...WITH ANOTHER OVER CNTRL ND. BOTH SHOULD SHEAR SEWD TODAY AS WRN PA UPR LOW LIFTS NE INTO THE ADIRONDACKS. ...LWR MO VLY INTO TN VLY... STATIONARY FRONTAL ZONE EXTENDING SEWD FROM THE LWR MO VLY INTO TN AND THE SRN APLCNS WILL BE THE FOCUS FOR SCATTERED STORMS THIS PERIOD. WHILE TIMING WITH RESPECT TO SHORTWAVE FEATURES DOES NOT APPEAR TO BE FAVORABLE...WEAKENING CINH PROVIDED BY SURFACE HEATING AND LIFT NEAR BOUNDARY SHOULD SUPPORT DEVELOPMENT OVER MO/AR AND W TN DURING THE AFTERNOON. THIS ACTIVITY SHOULD MOVE/DEVELOP ESE AND MAY EXPAND IN COVERAGE THROUGH LATE EVENING BEFORE DIMINISHING. HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE...BUT TORNADO THREAT APPEARS MARGINAL GIVEN LIMITED MOISTURE AVAILABILITY. CURRENT SURFACE OBSERVATIONS...GOES MICROWAVE SOUNDER PWS...AND AIR MASS MOVEMENTS IN RECENT DAYS SUGGEST THAT THE MODELS ARE OVER-FORECASTING BOUNDARY LAYER MOISTURE INVOF AFOREMENTIONED FRONT. EVEN ACCOUNTING FOR MID-MAY EVAPOTRANSPIRATION...EXPECT THAT SURFACE DEWPOINTS IN WELL MIXED ENVIRONMENT WILL AT BEST REMAIN LIMITED TO THE LOW TO MID 50S FROM MO INTO NRN AR...WITH LESSER VALUES EXTENDING E/SE INTO THE TN VLY. NEVERTHELESS...RELATIVELY COOL MID LEVEL TEMPERATURES AND STRONG SURFACE HEATING WILL CONTRIBUTE TO AN ENVIRONMENT OF STEEP /8-9 DEG C PER KM/ LOW-MID LEVEL LAPSE RATES OVER MO/AR. COUPLED WITH EVEN MODEST MOISTURE...THIS SHOULD YIELD MUCAPE OF 1000-1500 J/KG. GIVEN EXPECTED FAVORABLE VERTICAL SHEAR PROFILES ASSOCIATED WITH NWLY MID/UPR LEVEL FLOW...AND POSSIBLE INCREASE IN LARGE SCALE ASCENT TO BE PROVIDED LATER TODAY BY UPR IMPULSE NOW IN ND...SETUP COULD SUPPORT A FEW ROTATING STORMS WITH HAIL/HIGH WIND. SFC WINDS WILL BE VARIABLE...RANGING FROM SWLY IN WARM SECTOR TO SLY-SELY JUST E OF FRONT...RESULTING IN A LARGE VARIATION IN LOW LEVEL SHEAR PROFILES. BUT BOWING STRUCTURES WILL BE POSSIBLE WITH ANY STORMS THAT DO FORM GIVEN MODERATE MEAN FLOW AND LIKELY 20 DEG F TEMPERATURE-DEWPOINT SPREADS. ...INTERIOR PAC NW... WIND PROFILES WILL STRENGTHEN RELATIVE TO RECENT DAYS OVER INTERIOR PORTIONS OF ORE/WA AND WRN ID LATER TODAY AS E PACIFIC SHORTWAVE IMPULSE LIFTS NNE TOWARD REGION. SURFACE HEATING... POSSIBLY AIDED BY LARGE SCALE ASCENT FROM SHORTWAVE...LIKELY WILL YIELD SCATTERED AFTERNOON/EVENING STORMS OVER CNTRL/ERN ORE/WA AND POSSIBLY WRN ID....INITIALLY OVER THE HIGHER TERRAIN. THE MODERATE...LARGELY UNIDIRECTIONAL SSWLY CLOUD LAYER FLOW MAY SUPPORT DEVELOPMENT OF ONE OR MORE BANDS OF STORMS. COUPLED WITH LARGE TEMPERATURE-DEWPOINT SPREADS/STEEP LOW TO MID LEVEL LAPSE RATES...SOME OF THESE MAY CONTAINING BOWING SEGMENTS WITH HIGH WIND/MARGINALLY SEVERE HAIL. LOW LEVEL MOISTURE IN SOME SPOTS WILL BE AUGMENTED BY RECYCLING OF MOISTURE FROM OVERNIGHT CONVECTION...AND COULD LOCALLY BOOST AFTERNOON MUCAPE TO 1000 J/KG. ...NRN NJ TO SRN/CNTRL NEW ENGLAND... LINGERING AXIS OF LOW LEVEL CONFLUENCE IN SW QUADRANT OF RI/ERN MA SURFACE LOW MAY BE A FOCUS FOR TSTM DEVELOPMENT LATER TODAY AS MODEST AIR MASS RECOVERY OCCURS IN WAKE OF DENSE MORNING CLOUDS/PRECIP. GIVEN COLD MID LEVEL TEMPERATURES /BLO MINUS 20C AT 500 MB/... SOME OF THESE MAY PRODUCE HAIL AS MLCAPE CLIMBS TO AROUND 500 J/KG. STRONG-SVR TSTM POTENTIAL SHOULD DIMINISH WITH ONSET OF DIURNAL COOLING. ..CORFIDI/TAYLOR.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 16:45:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 12:45:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191633 SWODY1 SPC AC 191632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT FRI MAY 19 2006 VALID 191630Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE LOWER MO RIVER VALLEY INTO THE TN RIVER VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN INTERMOUNTAIN WEST... ...LOWER MO RIVER VALLEY INTO THE TN VALLEY... SURFACE ANALYSES INDICATE OUTFLOW BOUNDARY/STATIONARY FRONT EXTENDING SE-NW FROM THE MID SOUTH INTO CENTRAL/ERN MO. MORNING CONVECTION APPEARS TO BE TIED TO WEAK SHORTWAVE TROUGH NOW MOVING ACROSS THE LOWER OH RIVER VALLEY. WITH PERSISTENT SURFACE HEATING AHEAD OF THESE STORMS...ACTIVITY MAY INCREASE AND BECOME MARGINALLY SEVERE INTO WRN TN/NERN MS/NRN AL THIS AFTERNOON ONCE CAP WEAKENS. HOWEVER...MORE VIGOROUS ACTIVITY SHOULD DEVELOP AHEAD OF UPSTREAM SHORTWAVE TROUGH NOW MOVING SEWD ACROSS THE DAKOTAS. MODELS CONTINUE TO DRASTICALLY INCREASE SURFACE DEW POINTS AHEAD OF ADVANCING SURFACE COLD FRONT ASSOCIATED WITH APPROACHING SYSTEM. EXPECT NON-ADVECTIVE PROCESSES WILL ALLOW SOME INCREASE IN SURFACE DEW POINTS THROUGH THE AFTERNOON INTO SRN MO/NRN AR WITH DEW POINTS AROUND 60F POSSIBLE ACROSS THIS REGION. MODIFIED FORECAST SOUNDINGS INDICATE HEATING WILL SUPPORT MARGINAL TO MODERATE INSTABILITY WITH MLCAPES AROUND 1O00 J/KG LATE TODAY...WITH RATHER STRONG DEEP LAYER SHEAR UNDER NWLY FLOW ALOFT. EXPECT DEVELOPMENT WILL OCCUR BETWEEN 21-00Z NEAR TRIPLE POINT SURFACE LOW OVER MO AND POSSIBLY ALONG OUTFLOW BOUNDARY/WARM FRONT INTO THE LOWER OH RIVER VALLEY. WLY LLJ WILL BE SUSTAINED/INCREASE ACROSS THE MID SOUTH LATER TODAY AND THIS EVENING SUGGESTING ACTIVITY WILL INCREASE/SPREAD ESEWD INTO THE EARLY NIGHTTIME HOURS. DAMAGING WINDS AND LARGE HAIL WILL BE PRIMARY SEVERE THREATS. ...NRN INTERMOUNTAIN REGION INTO PORTIONS OF THE PAC NW... SLY FLOW ALOFT WILL STRENGTHEN ACROSS THIS REGION AHEAD OF SHORTWAVE TROUGH NOW APPROACHING THE PAC NW COAST. SURFACE DEW POINTS REMAIN IN THE LOWER 50S ALONG AND EAST OF THE CASCADES...SUGGESTING MODERATE INSTABILITY WILL DEVELOP OVER LOWER ELEVATIONS TODAY GIVEN RELATIVELY STEEP LAPSE RATES IN PLACE. DEVELOPMENT SHOULD INCREASE ALONG AND NEAR HIGHER TERRAIN FROM FAR NRN CA INTO CENTRAL ORE/WA BY 21Z...WITH STORMS PERSISTING AND STRENGTHENING AS THEY ENCOUNTER MODERATE INSTABILITY THROUGH THE EARLY EVENING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR SUFFICIENT FOR ORGANIZED LINES/SUPERCELLS WHICH WILL INCREASE THE THREAT OF LARGE HAIL/DAMAGING WINDS. TORNADO THREAT SHOULD BE MITIGATED BY RELATIVELY WEAK LOW LEVEL SHEAR FORECAST. ...COASTAL NEW ENGLAND... DEEP UPPER LOW IS SUSTAINING STRONG...FAST MOVING STORMS NOW APPROACHING THE ME COAST ALONG NWRN EDGE OF MARGINAL SBCAPE AXIS. SHEAR AND DEEP ASCENT REMAIN QUITE STRONG AND MAY ALLOW BRIEF SEVERE WIND GUSTS WITH THESE LINES AS THEY MOVE INLAND. FURTHER DEVELOPMENT MAY OCCUR DURING THE AFTERNOON AND ALSO LIFT QUICKLY NWD ALONG THE NEW ENGLAND COAST. FROM THE LOWER HUDSON INTO THE CT RIVER VALLEYS...ISOLATED HAIL...SOME NEAR SEVERE LIMITS...MAY ACCOMPANY STRONGER CELLS DEVELOPING IN CLOSER PROXIMITY TO UPPER LEVEL LOW/MID LEVEL COLD POCKET NOW MOVING INTO THE NERN U.S. ..EVANS/GUYER.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 20:01:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 16:01:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191958 SWODY1 SPC AC 191957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT FRI MAY 19 2006 VALID 192000Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID MS VALLEY AND TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE PACIFIC NORTHWEST... ...MID MS VALLEY/TN VALLEY... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BELT OF NWLY FLOW ACROSS THE MID MS AND TN VALLEYS. AT THE SFC..A STRONG MOISTURE GRADIENT EXISTS FROM ERN MO EXTENDING SEWD INTO WRN TN AND WRN AL. OBJECTIVE ANALYSIS HAS THE MAIN INSTABILITY AXIS FROM NWRN AR ACROSS SCNTRL MO. ALTHOUGH THIS AREA IS CURRENTLY CAPPED...LOW-LEVEL CONVERGENCE SHOULD INCREASE AS A COLD FRONT MOVES SWD ACROSS MO THIS AFTERNOON. THIS SHOULD BE ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG AND SOUTHEAST OF THE BOUNDARY LATE THIS AFTERNOON. OTHER STORMS WILL CONTINUE TO INITIATE IN WRN KY AND WRN TN. MODEL FORECASTS ARE GENERALLY CONSISTENT...DEVELOPING AN MCS IN SERN MO AND MOVING THE MCS SEWD ACROSS WRN KY AND TN THIS EVENING. FORECAST SOUNDINGS THIS EVENING ACROSS THE SLIGHT RISK AREA SHOW STRONG VERTICAL SHEAR PROFILES. THIS SHOULD BE FAVORABLE FOR SUPERCELLS ESPECIALLY EARLY IN THE DEVELOPMENT OF THE MCS OVER SERN MO WHERE INSTABILITY IS MAXIMIZED. DUE TO STEEP LAPSE RATES ACROSS MO AND AR...THIS AREA WILL HAVE THE GREATEST POTENTIAL FOR LARGE HAIL. AS THE MCS ORGANIZES AND MOVES SEWD INTO WRN KY AND WRN TN...A WIND DAMAGE THREAT WILL ALSO BE LIKELY WITH THE STRONGER MULTICELL CLUSTERS. THE SEVERE THREAT SHOULD GRADUALLY LESSEN AS THE MCS TRACKS SEWD ACROSS THE TN VALLEY DURING THE OVERNIGHT PERIOD. ...PACIFIC NORTHWEST... WATER VAPOR IMAGERY CURRENTLY SHOWS A HIGHLY AMPLIFIED UPPER-LEVEL TROUGH JUST OFF THE WEST COAST. AS THIS TROUGH MOVES SLOWLY TOWARD THE COAST THIS AFTERNOON...LARGE-SCALE ASCENT WILL INCREASE ACROSS THE PACIFIC NORTHWEST. THIS SHOULD CONTINUE TO SUPPORT THUNDERSTORM DEVELOPMENT ACROSS THE SLIGHT RISK AREA THIS AFTERNOON. OBJECTIVE ANALYSIS CURRENTLY SHOWS AN AXIS OF MODERATE INSTABILITY FROM WRN ID EXTENDING NWD INTO NRN ORE. THIS COMBINED WITH MODERATE VERTICAL SHEAR SHOWN ON REGIONAL WSR-88D VWPS SHOULD BE FAVORABLE FOR A FEW SUPERCELL STORMS IN ERN ORE...WRN ID AND SERN WA THIS AFTERNOON. THE INSTABILITY AND STEEP LAPSE RATES SHOWN ON OBJECTIVE ANALYSIS SUGGEST HAIL AND WIND DAMAGE WILL BE POSSIBLE WITH THE STRONGER STORMS. ...NEW ENGLAND STATES... WATER VAPOR IMAGERY CURRENTLY SHOWS THE CENTER OF AN UPPER-LOW OVER SERN NY ATTM. THUNDERSTORMS ARE DEVELOPING JUST AHEAD OF THE TRACK OF THE UPPER-LOW. COLD AIR ALOFT...STEEP LAPSE RATES AND STRONG LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-LOW WILL BE FAVORABLE FOR STRONG WIND GUSTS AND HAIL WITH THE STRONGER CELLS LATE THIS AFTERNOON. ..BROYLES.. 05/19/2006  From swody1 at goshenarc.org Sat May 20 01:12:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 21:12:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200108 SWODY1 SPC AC 200107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT FRI MAY 19 2006 VALID 200100Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS NERN ORE...SERN WA...NRN ID...EXTREME WRN MT... ...THERE IS A SLGT RISK OF SVR TSTMS ERN MO/SRN IL TO NRN AL/SWRN TN... ...SYNOPSIS... STABLE LONGWAVE PATTERN WILL SUPPORT CONTINUANCE OF WRN MEAN RIDGE AND ERN TROUGH. AS STRONG SHORTWAVE TROUGH DIGS SEWD FROM NRN MB TO NWRN ONT...UPPER LOW NOW OVER NEW ENGLAND WILL EJECT NNEWD OVER ST LAWRENCE RIVER VALLEY OF QUE. SUBTLE SHORTWAVE TROUGH AND ASSOCIATED MID-UPPER SPEED MAX WILL CONTINUE MOVING SEWD ACROSS LOWER MO VALLEY REGION TOWARD TN VALLEY OVERNIGHT...AS WILL ASSOCIATED SFC FRONTAL-WAVE LOW...ALONG NW-SE ALIGNED AND QUASISTATIONARY BAROCLINIC ZONE. MEANWHILE....DEEP-LAYER SSWLY FLOW WILL CONTINUE OVER PACIFIC NW AND NRN ROCKIES...WITH WEAK/EMBEDDED PERTURBATIONS MOVING INTO MEAN RIDGE POSITION. ...NWRN CONUS... SERN WA MCS WILL REMAIN PRIMARY FOCUS FOR SVR POTENTIAL AS IT MOVES NEWD WITH DAMAGING GUSTS AND OCCASIONAL HAIL POSSIBLE. ADDITIONAL SVR WIND/HAIL POTENTIAL REMAINS EWD TOWARD ID/MT BORDER REGION. REF WW 364 AND RELATED MESOSCALE DISCUSSIONS FOR NEAR-TERM THREATS. GEG SOUNDING REMAINS MISSING BECAUSE OF RAOB EQUIPMENT UPGRADES...HOWEVER MODIFIED BOI RAOB AND RUC FCST SOUNDINGS SUGGEST POCKETS OF 500-1000 J/KG MLCAPES WILL SUPPORT ACTIVITY AMIDST LOW-MIDLEVEL LAPSE RATES APCHG 9 DEG C/KM...WITH 40S-50S F SFC DEW POINTS. SVR RISK IS STRONGLY TIED TO PRESENCE OF DEEPLY HEATED/WELL-MIXED BOUNDARY LAYER IN INFLOW REGION OF TSTMS...AS WELL AS LIFT GENERATED ALONG LEADING EDGES OF COLD POOLS FROM MCS...AND SHOULD DIMINISH MARKEDLY AFTER SUNSET WHEN DIABATIC SFC COOLING WILL BE STRONGEST. ...LOWER MO VALLEY...OZARKS TO TN VALLEY REGION... CHANCE STILL EXISTS FOR SFC-BASED DEVELOPMENT OF SVR TSTMS INVOF SFC LOW AND FRONTAL ZONE OVER ERN MO FOR ANOTHER 1-2 HOURS...SUPPORTED BY FRONTAL LIFT...50-60 KT EFFECTIVE SHEAR...200-300 J/KG OF 0-3 KM SRH ALONG FRONT...AND MLCAPES APPROXIMATELY 1500 J/KG. SPECIFIC MORPHOLOGY AND TRACK OF ANY OVERNIGHT MCS WILL DEPEND ON RELATIVE INFLUENCE OF ANY SFC-FORCED STORMS THAT DEVELOP IN ANOTHER 1-2 HOURS VERSUS MORE ELEVATED DEVELOPMENT LATER TONIGHT...FARTHER SE ACROSS SERN MO/WRN KY/WRN TN REGION WHERE 30-40 KT WLY LLJ IS PROGGED. MOST CONCENTRATED ACTIVITY SHOULD MOVE PARALLEL AND CLOSE TO INSTABILITY GRADIENT ASSOCIATED WITH FRONTAL ZONE IN SFC-850 MB LAYER. MAIN CONCERN WILL BE DAMAGING GUSTS...THOUGH LAPSE RATES AND DEEP-LAYER SHEAR PROFILES SUPPORTING SUPERCELLS SUGGEST HAIL THREAT CONTINUES AS WELL. ..EDWARDS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 06:08:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 02:08:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200605 SWODY1 SPC AC 200603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT SAT MAY 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN KS TO COASTAL CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF WI... ...SYNOPSIS... SYNOPTIC PATTERN WILL CONTINUE TO FEATURE WRN CONUS RIDGE AND ERN TROUGH. STRONG SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN MB -- IS FCST TO AMPLIFY AS IT MOVES SEWD TOWARD MEAN TROUGH POSITION. THIS SHOULD RESULT IN SMALL...CLOSED...TIGHTLY DEFINED...MIDDLE-UPPER LEVEL LOW MOVING SEWD ACROSS LS AND LH THROUGH PERIOD. ASSOCIATED SFC COLD FRONT -- NOW PASSING SRN TIP OF LAKE MANITOBA AND MOVING SWWD ACROSS SRN SASK -- IS FCST BY 21/00Z TO EXTEND FROM SSM AREA SWWD ACROSS IL/WI BORDER REGION...THEN WWD ACROSS IA AND SRN SD...BECOMING QUASISTATIONARY OVER SERN-N-CENTRAL MT. FARTHER S...PERSISTENT/QUASISTATIONARY FRONTAL ZONE WILL EXTEND FROM CAROLINAS GENERALLY WWD ACROSS OZARKS TO SWRN KS/SERN CO. MEANWHILE...AS MID/UPPER LEVEL CYCLONE SLOWLY PIVOTS EWD OFFSHORE NRN CA/ORE...PERTURBATION NOW OVER CENTRAL/NRN CA WILL MOVE THROUGH MEAN RIDGE POSITION ACROSS NRN ROCKIES. ...SERN KS TO TN VALLEY... STRONG CAPPING SHOULD PRECLUDE DEVELOPMENT OVER MOST OR ALL OF WARM SECTOR S OF FRONT...WITH POSSIBLE EXCEPTION OF INTENSELY HEATED/MIXED BUT RELATIVELY DRY AIR MASS OVER SRN HIGH PLAINS. LARGEST PROBABILITIES FOR SVR WILL BE WITH LATE AFTERNOON THROUGH EVENING DEVELOPMENT ALONG AND N OF SFC FRONT FROM SERN KS THROUGH TN VALLEY REGION...MOVING SEWD THROUGH OVERNIGHT HOURS. RELATIVE TO AREAS FARTHER E...STEEPEST MIDLEVEL LAPSE RATES AND GREATEST CONDITIONAL POTENTIAL FOR LARGE HAIL WILL BE ACROSS THIS REGION...HOWEVER STRONGER CINH MAY LIMIT CONVECTIVE COVERAGE. LOW LEVEL VERTICAL SHEAR AND HODOGRAPH SIZE WILL BE MAXIMIZED INVOF FRONT WHERE SFC WINDS SHOULD BE WEAK AND BACKED DIRECTIONALLY...COMPARED TO WARM SECTOR. 0-3 KM SRH 200-500 J/KG ARE POSSIBLE ALONG AND WITHIN 50-100 NM N OF FRONT...WHERE EFFECTIVE LIFTED PARCELS STILL ARE ROOTED AT SFC IN FCST SOUNDINGS VALID LATE AFTERNOON/EVENING. THEREAFTER...ACTIVITY SHOULD BE MORE ELEVATED BUT ALSO GREATER IN COVERAGE...WITH LARGE HAIL AND OCCASIONAL DAMAGING GUSTS POSSIBLE. ...SRN APPALACHIANS TO COASTAL CAROLINAS... TWO ROUNDS OF SEVERE POTENTIAL POSSIBLE OVER THIS REGION...MORNING THEN AFTERNOON. SHORT PERIOD OF FAVORABLE SFC HEATING IS POSSIBLE AFTER 12Z...AHEAD OF CONVECTIVE COMPLEX NOW TAKING SHAPE OVER KY...NERN TN AMD FAR SWRN VA. GUSTS/HAIL NEAR SVR LEVELS ARE POSSIBLE WITH THIS ACTIVITY BEFORE IT MOVES OFFSHORE...LEAVING BEHIND REINFORCED/DISPLACED FRONTAL ZONE ACROSS PORTIONS SRN NC AND SC...WNWWD ACROSS NRN GA. THIS BOUNDARY AND ASSOCIATED INSTABILITY GRADIENT SHOULD SERVE AS PRIMARY FOCUS FOR SUBSEQUENT CONVECTIVE DEVELOPMENT/MOTION. AIR MASS RECOVERY IS EXPECTED ALONG BOUNDARY THROUGH LATE MORNING INTO LATE AFTERNOON...WITH ADDITIONAL DEVELOPMENT POSSIBLE AS SFC DIABATICALLY WARMS. WELL-MIXED BOUNDARY LAYERS ARE EXPECTED WITH DEW POINT DEPRESSIONS AROUND 30 DEG F...LEADING TO INVERTED-V THERMODYNAMIC PROFILES BELOW LCL AND SUPPORTING MAINTENANCE TO SFC OF ANY HAIL OR STRONG-SEVERE GUSTS GENERATED ALOFT. DEEP-LAYER VERTICAL SHEAR PROFILES WILL SUPPORT BOTH SUPERCELLULAR AND BOW MODES FOR CONVECTION. ...MT... SCATTERED TSTMS ARE EXPECTED TO DEVELOP OVER HIGHER TERRAIN OF WRN MT DURING DAY...MOVING EWD ACROSS HIGH PLAINS AND POSSIBLY CONGEALING INTO ORGANIZED LINE/CLUSTER OF TSTMS. DAMAGING WIND SHOULD BE MAIN THREAT WITH OCCASIONAL HAIL ALSO PSBL...AS ACTIVITY MOVES INTO DEEPLY HEATED/MIXED AIR MASS WITH STEEP LOW-MIDLEVEL LAPSE RATES ALONG AND W OF SFC FRONT. APCHG SHORTWAVE TROUGH SHOULD ENHANCE CONVECTIVE ENVIRONMENT THROUGH COMBINATION OF INCREASING LARGE SCALE ASCENT/COOLING ALOFT AND LEE-SIDE ISALLOBARIC/ISALLOHYPSIC FORCING IN LOW LEVELS ACROSS MT. LATTER WILL HELP TO MAINTAIN BACKED/ENHANCED SFC WINDS INVOF BAROCLINIC ZONE...AS WELL AS LOW LEVEL WAA AFTER DARK THAT MAY COMBINE WITH FRONTAL LIFT TO SUSTAIN SOME CONVECTION INTO EVENING OR EARLY OVERNIGHT HOURS AS FAR E AS WRN DAKOTAS/NERN WY. ...WI... CONDITIONAL SVR RISK EXISTS OVER THIS REGION...WITH ONLY MINOR ADJUSTMENTS IN INFLOW-LAYER DEW POINTS NEEDED TO SHIFT CONVECTIVE POTENTIAL FROM BAND OF WEAK SHOWERS TO SEVERE SQUALL LINE. STRONG DEEP-LAYER FORCING AND WEAK CINH SHOULD COUNTERACT WEAK MOISTURE ENOUGH TO RESULT IN POTENTIAL FOR FAST MOVING CONVECTION THIS AFTERNOON...WITH THREAT FOR HAIL AND DAMAGING GUSTS. AS SHORTWAVE TROUGH DIGS SEWD TOWARD LS...VERY STRONG LARGE SCALE DPVA/ASCENT WILL BE CONCENTRATED JUST TO ITS SE. MUCH OF THIS REGIME WILL OCCUR BENEATH LEFT EXIT REGION OF STRENGTHENING AND CYCLONICALLY CURVED...115-130 KT JET MAX AT 250 MB...AND ALSO...INVOF VIGOROUS LOW LEVEL FRONTOGENETIC FORCING. ALTHOUGH BOUNDARY LAYER MOISTURE WILL BE MRGL WITH SFC DEW POINTS 40S TO LOW 50S F...SFC HEATING COMBINED WITH COOLING ALOFT SHOULD CONTRIBUTE TO DEEP ENOUGH BUOYANCY PROFILE FOR DEEP CONVECTION. SVR THREAT WILL DIMINISH EWD THIS EVENING ACROSS LM AND LOWER MI WHERE LOW LEVEL AIR MASS SHOULD BE MORE STABLE. ..EDWARDS/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 06:23:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 02:23:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200620 SWODY1 SPC AC 200618 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0118 AM CDT SAT MAY 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN KS TO COASTAL CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF WI... ...SYNOPSIS... SYNOPTIC PATTERN WILL CONTINUE TO FEATURE WRN CONUS RIDGE AND ERN TROUGH. STRONG SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN MB -- IS FCST TO AMPLIFY AS IT MOVES SEWD TOWARD MEAN TROUGH POSITION. THIS SHOULD RESULT IN SMALL...CLOSED...TIGHTLY DEFINED...MIDDLE-UPPER LEVEL LOW MOVING SEWD ACROSS LS AND LH THROUGH PERIOD. ASSOCIATED SFC COLD FRONT -- NOW PASSING SRN TIP OF LAKE MANITOBA AND MOVING SWWD ACROSS SRN SASK -- IS FCST BY 21/00Z TO EXTEND FROM SSM AREA SWWD ACROSS IL/WI BORDER REGION...THEN WWD ACROSS IA AND SRN SD...BECOMING QUASISTATIONARY OVER SERN-N-CENTRAL MT. FARTHER S...PERSISTENT/QUASISTATIONARY FRONTAL ZONE WILL EXTEND FROM CAROLINAS GENERALLY WWD ACROSS OZARKS TO SWRN KS/SERN CO. MEANWHILE...AS MID/UPPER LEVEL CYCLONE SLOWLY PIVOTS EWD OFFSHORE NRN CA/ORE...PERTURBATION NOW OVER CENTRAL/NRN CA WILL MOVE THROUGH MEAN RIDGE POSITION ACROSS NRN ROCKIES. ...SERN KS TO TN VALLEY... STRONG CAPPING SHOULD PRECLUDE DEVELOPMENT OVER MOST OR ALL OF WARM SECTOR S OF FRONT...WITH POSSIBLE EXCEPTION OF INTENSELY HEATED/MIXED BUT RELATIVELY DRY AIR MASS OVER SRN HIGH PLAINS. LARGEST PROBABILITIES FOR SVR WILL BE WITH LATE AFTERNOON THROUGH EVENING DEVELOPMENT ALONG AND N OF SFC FRONT FROM SERN KS THROUGH TN VALLEY REGION...MOVING SEWD THROUGH OVERNIGHT HOURS. RELATIVE TO AREAS FARTHER E...STEEPEST MIDLEVEL LAPSE RATES AND GREATEST CONDITIONAL POTENTIAL FOR LARGE HAIL WILL BE ACROSS THIS REGION...HOWEVER STRONGER CINH MAY LIMIT CONVECTIVE COVERAGE. LOW LEVEL VERTICAL SHEAR AND HODOGRAPH SIZE WILL BE MAXIMIZED INVOF FRONT WHERE SFC WINDS SHOULD BE WEAK AND BACKED DIRECTIONALLY...COMPARED TO WARM SECTOR. 0-3 KM SRH 200-500 J/KG ARE POSSIBLE ALONG AND WITHIN 50-100 NM N OF FRONT...WHERE EFFECTIVE LIFTED PARCELS STILL ARE ROOTED AT SFC IN FCST SOUNDINGS VALID LATE AFTERNOON/EVENING. THEREAFTER...ACTIVITY SHOULD BE MORE ELEVATED BUT ALSO GREATER IN COVERAGE...WITH LARGE HAIL AND OCCASIONAL DAMAGING GUSTS POSSIBLE. ...SRN APPALACHIANS TO COASTAL CAROLINAS... TWO ROUNDS OF SEVERE POTENTIAL POSSIBLE OVER THIS REGION...MORNING THEN AFTERNOON. SHORT PERIOD OF FAVORABLE SFC HEATING IS POSSIBLE AFTER 12Z...AHEAD OF CONVECTIVE COMPLEX NOW TAKING SHAPE OVER KY...NERN TN AMD FAR SWRN VA. GUSTS/HAIL NEAR SVR LEVELS ARE POSSIBLE WITH THIS ACTIVITY BEFORE IT MOVES OFFSHORE...LEAVING BEHIND REINFORCED/DISPLACED FRONTAL ZONE ACROSS PORTIONS SRN NC AND SC...WNWWD ACROSS NRN GA. THIS BOUNDARY AND ASSOCIATED INSTABILITY GRADIENT SHOULD SERVE AS PRIMARY FOCUS FOR SUBSEQUENT CONVECTIVE DEVELOPMENT/MOTION. AIR MASS RECOVERY IS EXPECTED ALONG BOUNDARY THROUGH LATE MORNING INTO LATE AFTERNOON...WITH ADDITIONAL DEVELOPMENT POSSIBLE AS SFC DIABATICALLY WARMS. WELL-MIXED BOUNDARY LAYERS ARE EXPECTED WITH DEW POINT DEPRESSIONS AROUND 30 DEG F...LEADING TO INVERTED-V THERMODYNAMIC PROFILES BELOW LCL AND SUPPORTING MAINTENANCE TO SFC OF ANY HAIL OR STRONG-SEVERE GUSTS GENERATED ALOFT. DEEP-LAYER VERTICAL SHEAR PROFILES WILL SUPPORT BOTH SUPERCELLULAR AND BOW MODES FOR CONVECTION. ...MT... SCATTERED TSTMS ARE EXPECTED TO DEVELOP OVER HIGHER TERRAIN OF WRN MT DURING DAY...MOVING EWD ACROSS HIGH PLAINS AND POSSIBLY CONGEALING INTO ORGANIZED LINE/CLUSTER OF TSTMS. DAMAGING WIND SHOULD BE MAIN THREAT WITH OCCASIONAL HAIL ALSO PSBL...AS ACTIVITY MOVES INTO DEEPLY HEATED/MIXED AIR MASS WITH STEEP LOW-MIDLEVEL LAPSE RATES ALONG AND W OF SFC FRONT. APCHG SHORTWAVE TROUGH SHOULD ENHANCE CONVECTIVE ENVIRONMENT THROUGH COMBINATION OF INCREASING LARGE SCALE ASCENT/COOLING ALOFT AND LEE-SIDE ISALLOBARIC/ISALLOHYPSIC FORCING IN LOW LEVELS ACROSS MT. LATTER WILL HELP TO MAINTAIN BACKED/ENHANCED SFC WINDS INVOF BAROCLINIC ZONE...AS WELL AS LOW LEVEL WAA AFTER DARK THAT MAY COMBINE WITH FRONTAL LIFT TO SUSTAIN SOME CONVECTION INTO EVENING OR EARLY OVERNIGHT HOURS AS FAR E AS WRN DAKOTAS/NERN WY. ...WI... CONDITIONAL SVR RISK EXISTS OVER THIS REGION...WITH ONLY MINOR ADJUSTMENTS IN INFLOW-LAYER DEW POINTS NEEDED TO SHIFT CONVECTIVE POTENTIAL FROM BAND OF WEAK SHOWERS TO SEVERE SQUALL LINE. STRONG DEEP-LAYER FORCING AND WEAK CINH SHOULD COUNTERACT WEAK MOISTURE ENOUGH TO RESULT IN POTENTIAL FOR FAST MOVING CONVECTION THIS AFTERNOON...WITH THREAT FOR HAIL AND DAMAGING GUSTS. AS SHORTWAVE TROUGH DIGS SEWD TOWARD LS...VERY STRONG LARGE SCALE DPVA/ASCENT WILL BE CONCENTRATED JUST TO ITS SE. MUCH OF THIS REGIME WILL OCCUR BENEATH LEFT EXIT REGION OF STRENGTHENING AND CYCLONICALLY CURVED...115-130 KT JET MAX AT 250 MB...AND ALSO...INVOF VIGOROUS LOW LEVEL FRONTOGENETIC FORCING. ALTHOUGH BOUNDARY LAYER MOISTURE WILL BE MRGL WITH SFC DEW POINTS 40S TO LOW 50S F...SFC HEATING COMBINED WITH COOLING ALOFT SHOULD CONTRIBUTE TO DEEP ENOUGH BUOYANCY PROFILE FOR DEEP CONVECTION. SVR THREAT WILL DIMINISH EWD THIS EVENING ACROSS LM AND LOWER MI WHERE LOW LEVEL AIR MASS SHOULD BE MORE STABLE. ..EDWARDS/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 12:46:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 08:46:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201243 SWODY1 SPC AC 201242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT SAT MAY 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SE KS/THE OZARKS TO THE TN VLY...N GA...SC... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF WI AND MI... ...SYNOPSIS... AMPLIFIED PATTERN WILL PREVAIL AGAIN TODAY ACROSS THE CONUS. THE MAIN LARGE SCALE FEATURES WILL CONTINUE TO BE RIDGE ALONG THE RCKYS... BROAD TROUGH OVER ONTARIO/QUEBEC...AND MORE ELONGATED TROUGH OFF THE W CST. SEVERAL SHORTWAVE IMPULSES LIKELY WILL MODULATE TSTM DEVELOPMENT TODAY. THE FIRST OF THESE...NOW OVER ERN ORE...SHOULD CONTINUE NNE INTO SE AB BY THIS EVENING. FARTHER DOWNSTREAM IN SAME BAND OF FLOW...SATELLITE AND RUC ANALYSES DEPICT A SERIES OF WEAKER DISTURBANCES SHEARING SEWD FROM THE DAKOTAS THROUGH THE LWR MO VLY INTO TN AND THE CAROLINAS. IN THE NRN STREAM...A MUCH STRONGER IMPULSE NOW IN FAR WRN ONTARIO SHOULD REACH LK SUPERIOR/UPR MI BY TONIGHT...AND LK HURON EARLY SUNDAY. ...SE KS/OZARKS INTO TN/N GA/SC... WEAK FRONT NOW IN PLACE FROM SRN KS/SRN MO INTO MIDDLE TN AND SRN NC SHOULD REMAIN MORE OR LESS STATIONARY OR SETTLE JUST SLIGHTLY S TODAY. THE BOUNDARY LIKELY WILL SERVE AS A FOCUS FOR DIURNAL STORM DEVELOPMENT...ESPECIALLY FROM N GA WNW INTO NRN AL AND MIDDLE/WRN TN...WHERE HEATING SHOULD BE STRONGEST AND CINH RELATIVELY WEAK. TRUE/DEEPLY MIXED BOUNDARY LAYER DEWPOINTS SHOULD REMAIN IN THE UPR 50S TO LOW 60S. BUT GIVEN STRONG HEATING AND STEEP MID LEVEL LAPSE RATES ON SWRN FRINGE OF GRT LKS TROUGH...AFTERNOON SBCAPE SHOULD RANGE FROM 1500-2000 J/KG. A BIT LATER IN THE DAY...STORMS MAY ALSO FORM WWD ALONG FRONT INTO NRN AR/SRN MO. 30 KT WNWLY MID LEVEL FLOW AND WEAK IMPULSES ALOFT SHOULD SUPPORT ORGANIZED STORMS/STORM CLUSTERS WITH HAIL AND HIGH WIND. WHILE A FEW ROTATING STORMS MAY OCCUR...FAIRLY LARGE TEMP-DEWPOINT SPREADS AND FOCUSED LOW LEVEL FORCING SUGGEST PREFERRED EVOLUTION TOWARD COLD-POOL DRIVEN CLUSTERS WITH BOWING SEGMENTS/HIGH WIND. FARTHER W/SW...SUBSTANTIAL CAP EXPECTED TO PROHIBIT WARM SECTOR DEVELOPMENT...EXCEPT PERHAPS FOR A BRIEF PERIOD LATE THIS AFTERNOON/EARLY THIS EVENING INVOF LEE TROUGH OVER WRN OK AND THE TX PANHANDLE. LATER TONIGHT/EARLY SUNDAY...ADDITIONAL STORMS MAY FORM IN WAA AREA ALONG AND N OF STALLED FRONT IN SE KS AND SRN/CNTRL MO. IT APPEARS THAT LLJ WILL STRENGTHEN AS A RESULT OF BOTH DIURNAL INFLUENCES...AND THE CONTINUED SE MOTION OF WRN ONTARIO DISTURBANCE. SUFFICIENT SHEAR/INSTABILITY MAY BE PRESENT FOR ELEVATED STORMS WITH HAIL AND POSSIBLY HIGH WIND. ...MT/NRN PLNS... SCATTERED TSTMS SHOULD FORM OVER THE MOUNTAINS OF WRN MT TODAY ...WITH MOVEMENT/DEVELOPMENT EXPECTED TO SPREAD E/NE INTO THE NRN HI PLAINS AS ORE UPR IMPULSE CONTINUES NNEWD. SUSTAINED FORCING FOR ASCENT AND MODERATE TEMP-DEWPOINT SPREADS SHOULD FAVOR EVOLUTION INTO A LINE/CLUSTER MODE WITH DAMAGING WIND AND MARGINALLY SEVERE HAIL. BACKED/SLIGHTLY UPSLOPE FLOW ALONG LEE TROUGH OVER THE CNTRL PART OF THE STATE SHOULD ENHANCE LOW LEVEL CONVERGENCE...AND FORWARD PROPAGATION OF STORMS INTO ERN MT BY MID TO LATE EVENING. LATER TONIGHT...WAA MAY INCREASE OVER THE WRN DAKOTAS ON BACK SIDE OF SURFACE RIDGE BUILDING SWD IN WAKE OF ONTARIO DISTURBANCE. ENHANCED FRONTAL UPLIFT AND LARGE SCALE ASCENT IN ENTRANCE REGION OF ASSOCIATED UPR LEVEL JET STREAK MAY SUSTAIN SOME OF THE STORMS INTO EARLY SUNDAY OVER THE WRN DAKOTAS/NE WY. ...WI/MI... LARGE SCALE FORCING FOR ASCENT WILL INCREASE SUBSTANTIALLY ACROSS THE UPR GRT LKS REGION TODAY AS POTENT WRN ONTARIO TROUGH DROPS SE TOWARD LK SUPERIOR. BOUNDARY LAYER MOISTURE WILL BE LIMITED... WITH AVERAGE SURFACE DEWPOINTS LIKELY REMAINING IN THE MID 40S ACROSS WI AND MI. BUT COINCIDENTAL ARRIVAL OF STRONG FRONTOGENETIC FORCING WITH DAYTIME HEATING/STEEPENING LOW LEVEL LAPSE RATES...AND STRENGTHENING OF MEAN WNWLY FLOW TO AOA 40 KTS...ALL SUGGEST POTENTIAL FOR A STRONGLY FORCED LINE OF LOW-TOPPED/ LOW-REFLECTIVITY STORMS WITH DAMAGING WIND. THIS ACTIVITY MAY REACH AS FAR S AS THE MKE/GRR/MBS AREAS BEFORE WEAKENING OVER SERN LWR MI LATER TONIGHT. ..CORFIDI/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 16:25:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 12:25:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201618 SWODY1 SPC AC 201616 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1116 AM CDT SAT MAY 20 2006 VALID 201630Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OZARKS TO THE CAROLINA COAST... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE CENTRAL GREAT LAKES... ...MID SOUTH ACROSS SRN APPALACHIANS INTO THE COASTAL CAROLINAS... QUASI-STATIONARY FRONT EXTENDING FROM FAR SRN MO ESEWD INTO MIDDLE TN AND EWD INTO THE PIEDMONT OF NC/VA THIS MORNING WILL PROVIDE PRIMARY FOCUS FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON/EVENING. SURFACE OUTFLOW BOUNDARY ACROSS SERN SC INTO NRN GA MAY PROVIDE ADDITIONAL FOCUS. THOUGH MID/UPPER LEVEL PATTERN REMAINS MORE LIKE MID-SUMMER...WARM SECTOR MOISTURE IS NOT OVERLY IMPRESSIVE WITH SURFACE DEW POINTS IN THE LOWER TO MID 60S. LIMITED LARGE SCALE ASCENT AND RISING HEIGHTS AT H5 INDICATE DEVELOPMENT WILL BE DRIVEN BY HEATING TODAY. LACK OF LARGE SCALE FOCUS AND LIMITED LLJ DEVELOPMENT SUGGEST THUNDERSTORMS COULD INITIATE ANYWHERE ALONG THE FRONT/OUTFLOW BOUNDARY THIS AFTERNOON...WHERE POCKETS OF WEAK CINH DEVELOP. HOWEVER...SATELLITE IMAGERY AND RECENT CONVECTIVE TRENDS MAY SUPPORT WEAK IMPULSE NOW MOVING ESEWD ACROSS MIDDLE TN WHICH COULD FOCUS INITIAL DEVELOPMENT ACROSS THE SRN APPALACHIANS EARLY THIS AFTERNOON. MODELS ARE AGAIN FAR TOO MOIST NEAR THE SURFACE AND APPEAR TO BE OVER FORECASTING EXPECTED SBCAPE/MLCAPE TODAY. HOWEVER...MLCAPE MAY STILL APPROACH 2000 J/KG ACROSS THE UPPER SOUTH /SOUTH OF SURFACE BOUNDARY/ WHERE AFTERNOON TEMPS APPROACH/EXCEED 90F. MODEST WLY FLOW ALOFT WILL ALSO SUSTAIN 35-45 KT EFFECTIVE SHEAR...SUPPORTIVE OF SUPERCELLS AND ORGANIZATION INTO SMALL LINES/BOW ECHOES MOVING SEWD LATER TODAY AND THIS EVENING. STEEP SUB-CLOUD LAPSE RATES AND NEAR UNIDIRECTIONAL FLOW ALOFT WILL SUPPORT PRIMARY THREAT OF DAMAGING WINDS. THOUGH PRESENCE OF SURFACE BOUNDARY MAY ENHANCE LOW LEVEL SHEAR ENOUGH FOR A TORNADO OR TWO...WHILE MLCAPE AND STEEP LAPSE RATES ALSO SUPPORT LARGE HAIL. ...SRN HIGH PLAINS INTO THE OZARKS... BOUNDARY WILL REMAIN STALLED NEAR THE MO/AR BORDER INTO FAR SRN KS/NWRN OK TODAY...AS WEAK LOW CENTER PERSISTS ALONG TRIPLE POINT OF FRONT AND DRY LINE NEAR THE TX/OK PANHANDLES. STRONG HEATING AND INFLUX OF ASCENT AHEAD OF WEAK SHORTWAVE TROUGH NOW SHIFTING SEWD ACROSS NEB SHOULD SUPPORT A FEW THUNDERSTORMS NEAR THIS BOUNDARY LATER TODAY. WRN END OF FRONT ACROSS NRN EXTENT OF SRN PLAINS REMAINS UNDER MID LEVEL RIDGE AND ASSOCIATED WEAK MID LEVEL FLOW... SUGGESTING STORMS ACROSS THIS AREA WILL BE MORE PULSE IN NATURE WITH BRIEF DAMAGING WINDS/HAIL. STORMS WHICH CAN DEVELOP AHEAD OF WEAK MID LEVEL SYSTEM INTO SRN MO/FAR SERN KS WILL HAVE MODEST SHEAR AND LIKELY ORGANIZE INTO MULTICELL CLUSTERS/LINES WITH THREATS OF LARGE HAIL/DAMAGING WINDS LATE TODAY AND THIS EVENING. ...MT INTO FAR NERN WY... WELL DEFINED SHORTWAVE TROUGH NOW LIFTING ACROSS THE NRN INTERMOUNTAIN REGION WILL INCREASE MOIST CONVECTION ACROSS THE NRN ROCKIES TODAY...WHERE MODEST LAPSE RATES AND SURFACE DEW POINTS AROUND 50F WILL SUPPORT MARGINAL TO MODERATE INSTABILITY TODAY. ASSOCIATED 40-50 KT SWLY MID LEVEL SPEED MAX WILL ALSO INCREASE DEEP LAYER SHEAR ACROSS MUCH OF WRN/CENTRAL MT AND NRN WY THIS AFTERNOON...WHERE FORECAST SOUNDINGS YIELD SUFFICIENT DEEP LAYER SHEAR FOR A FEW SUPERCELLS AND ORGANIZED CLUSTERS/LINES. SURFACE COLD FRONT NOW MOVING SWD INTO THE NRN PLAINS HAS PUSHED WWD INTO ERN MT THIS MORNING AND MAY LIMIT EWD EXTENT OF ANY SEVERE THREAT LATER THIS EVENING. HOWEVER...ACTIVITY INCREASING ACROSS WRN MT INTO NRN WY WILL LIKELY BECOME SEVERE OVER LOWER ELEVATIONS GIVEN STRONG HEATING AND SHIFT ENEWD THROUGH THE EVENING. ...CENTRAL GREAT LAKES... SEVERE THREAT APPEARS CONDITIONAL ACROSS THIS REGION AS PRE-FRONTAL BOUNDARY LAYER MOISTURE AND MID LEVEL LAPSE RATES REMAIN WEAK THIS MORNING. HOWEVER...STRONG COLD FRONT ASSOCIATED WITH DEEPENING SHORTWAVE TROUGH NOW SHIFTING SSEWD INTO THE NRN GREAT LAKES WILL SUPPORT STRONG LARGE SCALE ASCENT ACROSS THE CENTRAL GREAT LAKES TODAY. MODELS CONTINUE TO INCREASE SURFACE DEW POINTS INTO THE LOWER 50S IMMEDIATELY AHEAD OF APPROACHING COLD FRONT. HOWEVER...LATEST OBSERVATIONAL DATA SUGGESTS THIS MAY BE OVERDONE AND CASTS SOME DOUBT AS TO WHETHER OR NOT SUFFICIENT INSTABILITY WILL DEVELOP FOR SURFACE-BASED CONVECTION ALONG THE FRONT. SHOULD THUNDERSTORMS FORM WITHIN NARROW AXIS OF MARGINAL INSTABILITY TODAY...VERY STRONG WINDS ALOFT AND INCREASING LARGE SCALE ASCENT COULD SUPPORT DAMAGING WINDS AS STEEP SUB-CLOUD LAPSE RATES DEVELOP FROM SURFACE TEMPERATURES APPROACHING 70F. ..EVANS/GUYER.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 20:06:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 16:06:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 202002 SWODY1 SPC AC 202001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT SAT MAY 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF MT AND WY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID MS VALLEY...TN VALLEY AND CAROLINAS... ...CAROLINAS/TN VALLEY/OZARK PLATAEA... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BAND OF NORTHWEST FLOW ACROSS THE MID-MS AND TN VALLEYS. AT THE SFC...A NEARLY STATIONARY FRONT EXTENDS EWD ACROSS NRN TN INTO NC. SOUTH OF THE BOUNDARY...SFC DEWPOINTS ARE IN THE 60S F AND MODERATE INSTABILITY EXISTS. AN MCS IS CURRENTLY DEVELOPING ALONG THE NRN EDGE OF THE INSTABILITY AXIS AHEAD OF A SUBTLE SHORTWAVE TROUGH IN THE SRN APPALACHIAN MTNS. THIS STORM COMPLEX WILL CONTINUE TO EXPAND AND SPREAD ESEWD ACROSS NRN GA AND WRN SC LATE THIS AFTERNOON INTO THE EARLY EVENING. FORECAST SOUNDINGS LATE THIS AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ALONG THE FRONTAL BOUNDARY IN THE TN VALLEY AND CAROLINAS SUGGESTING SUPERCELLS WILL BE LIKELY ESPECIALLY EARLY IN THE DEVELOPMENT OF THE MCS. THE TORNADO THREAT SHOULD BE ENHANCED OVER NRN GA AND WRN SC WHERE THE LOW-LEVEL SHEAR ENVIRONMENT APPEARS MORE FAVORABLE DUE TO A 30-40 KT LOW-LEVEL JET. IN ADDITION...OBJECTIVE ANALYSIS SHOWS A PLUME OF STEEP MID-LEVEL LAPSE RATES EXTENDING EWD ACROSS MS...AL AND NRN GA SUGGESTING SUPERCELLS WITH VERY LARGE HAIL WILL ALSO BE POSSIBLE. AS THE MCS MATURES THIS EVENING...THE UNIDIRECTIONAL WIND ENVIRONMENT SUGGESTS THE WIND DAMAGE THREAT MAY ALSO BECOME ENHANCED. FURTHER WEST ACROSS THE OZARK PLATEAU...CONVECTIVE INITIATION WILL LIKELY HOLD OFF DUE TO A CAPPING INVERSION UNTIL THE LATE AFTERNOON AND/OR EARLY EVENING. FORECAST SOUNDINGS IN THIS AREA FOR EARLY THIS EVENING SHOW STEEP LAPSE RATES AND MODERATE VERTICAL SHEAR PROFILES SUGGESTING LARGE HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE. THE SEVERE THREAT MAY PERSIST THROUGH THE EVENING WITH ANY MCS CLUSTER THAN DEVELOPS AND MOVES ESEWD ACROSS THE REGION. ...MT/WY... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL RIDGE IN PLACE ACROSS THE ROCKIES WITH A SHORTWAVE TROUGH TOPPING THE RIDGE. AT THE SFC...A TROUGH CURRENTLY EXTENDS NNWD INTO NRN WY AND WCNTRL MT. SFC DEWPOINTS EAST OF THE SFC TROUGH RANGE FROM THE MID 40S TO MID 50S F WHERE POCKETS OF MODERATE INSTABILITY ARE PRESENT ACCORDING TO OBJECTIVE ANALYSIS. A LINE OF STRONG THUNDERSTORMS IS ORGANIZING IN THE FOOTHILLS AND WILL INCREASE IN COVERAGE...MOVING INTO THE PLAINS THIS AFTERNOON. FORECAST SOUNDINGS THIS AFTERNOON SHOW MODERATE VERTICAL SHEAR PROFILES SUGGESTING ISOLATED SUPERCELLS WITH LARGE HAIL WILL BE POSSIBLE WHERE THE INSTABILITY IS LOCALLY MAXIMIZED. IF LINEAR MCS DEVELOPMENT CONTINUES...BOW ECHOES EMBEDDED WITH THE LINE WOULD ALSO BE LIKELY WITH A THREAT FOR WIND DAMAGE THROUGH EARLY EVENING. ...UPPER GREAT LAKES... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BAND OF NWLY FLOW ACROSS THE UPPER MIDWEST. AN 80 KT MID-LEVEL JET EMBEDDED IN THE FLOW IS PUNCHING SEWD ACROSS THE REGION WHICH IS ENHANCING VERTICAL SHEAR PROFILES. MODEL FORECASTS SHOW LINEAR CONVECTIVE DEVELOPMENT MOVING SEWD ACROSS THE REGION LATE THIS AFTERNOON. ALTHOUGH INSTABILITY IS WEAK...THE STRONG SHEAR ENVIRONMENT SUGGESTS A MARGINAL WIND DAMAGE AND/OR HAIL THREAT MAY EXIST WITH THIS CONVECTION FOR A FEW HOURS THIS AFTERNOON. ..BROYLES.. 05/20/2006  From swody1 at goshenarc.org Sun May 21 01:12:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 21:12:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210109 SWODY1 SPC AC 210107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT SAT MAY 20 2006 VALID 210100Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SE KS TO SC COAST... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS ERN MT...NERN WY...EXTREME WRN SD... ...SYNOPSIS... LARGE SCALE PATTERN CONTINUES TO FEATURE ERN CONUS MEAN TROUGH AND RIDGE FROM N-CENTRAL MEX ACROSS CENTRAL ROCKIES TO CANADIAN NW TERRITORIES. EMBEDDED IN PREVAILING NW FLOW...WEAK SHORTWAVE TROUGH IS EVIDENT IN MOISTURE CHANNEL IMAGERY AND VWP/PROFILER DATA OVER PORTIONS IL/MO. THIS FEATURE IS FCST TO TURN ESEWD THEN EWD ACROSS SRN APPALACHIANS AS IT MOVES THROUGH MEAN TROUGH POSITION...REACHING INVOF TIDEWATER REGION OF ATLANTIC COAST BY END OF PERIOD. AT SFC...QUASISTATIONARY BAROCLINIC ZONE -- MODULATED/SHIFTED ON MESOBETA SCALE BY CONVECTIVE OUTFLOWS TO ITS S -- IS ANALYZED FROM ERN VA WSWWD ACROSS TN...AR/MO BORDER REGION AND KS/OK BORDER REGION...BECOMING DIFFUSE WWD INTO S-CENTRAL ROCKIES. SECONDARY/REINFORCING FRONTAL SURGE -- ASSOCIATED WITH GREAT LAKES MID/UPPER TROUGH -- IS ANALYZED FROM LH WSWWD ACROSS NRN/WRN LOWER MI...NRN IA...WRN SD...E-CENTRAL MT. THIS FRONT SHOULD CONTINUE TO MOVE SEWD THROUGH REMAINDER LM/LH AND ADJOINING PARTS MI/WI...SWD ACROSS N-CENTRAL PLAINS AND SLOWLY WWD OVER NRN HIGH PLAINS. ...OZARK REGION TO CAROLINAS COAST... REF SPC WWS 368...370...371 AND RELATED MESOSCALE DISCUSSIONS FOR NOWCAST SCENARIO ACROSS THIS REGION. LARGE SCALE ASCENT AHEAD OF MIDLEVEL PERTURBATION...30-40 KT LLJ AND NARROW PLUME OF AT LEAST MRGL 925-850 MB LAYER MOISTURE WILL SUPPORT CLUSTERS OF TSTMS THROUGH MUCH OF THIS SWATH...WITH EPISODIC POTENTIAL FOR SVR HAIL AND DAMAGING GUSTS. LATE THIS EVENING INTO OVERNIGHT HOURS...CORRIDOR OF MOST FAVORABLE SEVERE POTENTIAL WILL BE NARROWED FROM N-S AND RENDERED MORE ELEVATED/MRGL. THIS WILL OCCUR AS 1. COLLECTIVE CONVECTIVE OUTFLOWS EFFECTIVELY SHUNT FRONTAL ZONE SWD...AND AS 2. POCKETS OF RELATIVELY DRY AND WELL MIXED BOUNDARY LAYER AIR -- NOW ANALYZED IN SFC CHARTS FROM CENTRAL MS TO CENTRAL GA -- ADVECT ENEWD WHILE DIABATICALLY COOLING AND DESTABILIZING. ...NRN HIGH PLAINS... AREA OF OPTIMAL SEVERE POTENTIAL IS SHRINKING AS PRIMARY CENTRAL MT MCS MOVES INTO SUBSTANTIALLY MORE STABLE AIR MASS ALONG AND E OF SFC FRONT...REPRESENTED BY 00Z GGW RAOB. REF WW 367 AND LATEST ACCOMPANYING MESOSCALE DISCUSSION FOR MORE DETAILS. OVERALL SEVERE POTENTIAL SHOULD DIMINISH AFTER DARK AS BOUNDARY LAYER COOLS BETWEEN FRONT AND CONVECTIVE FORCING BOUNDARIES. WAA AND WEAK MOIST ADVECTION -- ASSOCIATED WITH SELY-SSELY LLJ OF 30-40 KT -- MAY HELP TO SUSTAIN SOME OF THIS CONVECTION AFTER 6Z...WITH HAIL/GUSTS TO NEAR SVR LEVELS POSSIBLE. ..EDWARDS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 06:05:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 02:05:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210601 SWODY1 SPC AC 210559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT SUN MAY 21 2006 VALID 211200Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS ERN ORE...SERN WA...WRN ID... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS MT...EXTREME N-CENTRAL WY... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL KS TO WRN KY AND NWRN TN... ...SYNOPSIS... STABLE LARGE SCALE PATTERN WITH MEAN WRN RIDGE AND ERN TROUGH WILL CONTINUE...BUT WITH SOME IMPORTANT SHORTWAVE CHANGES DURING DAY-1. STRONG MID/UPPER LEVEL LOW INITIALLY OVER UPPER GREAT LAKES IS FCST TO TURN EWD THEN NEWD PAST MEAN TROUGH POSITION...THEN PRONOUNCED MID/UPPER LEVEL LOW -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY INVOF 35N130W...HAS BEGUN SLGT SEWD TURN AND SHOULD CONTINUE THIS TREND THROUGH PERIOD. LOW SHOULD BE LOCATED JUST OFFSHORE SRN CA/NRN BAJA BY 22/12Z...WITH ASSOCIATED LOW LEVEL BAROCLINIC ZONE INCREASING CONVECTIVE POTENTIAL ACROSS MUCH OF CENTRAL/SRN CA WITH TIME THROUGH DAY-1. HEIGHTS ALSO SHOULD FALL ACROSS PACIFIC NW MID-LATE PERIOD IN RESPONSE TO SPEED MAX NOW DIGGING SEWD ACROSS GULF OF AK. AT SFC...RAGGED BAROCLINIC ZONE WITH MESOBETA SCALE OUTFLOW ENHANCEMENTS WILL PERSIST FROM SC COAST WNWWD OVER OZARKS REGION AND SRN KS...BECOMING DIFFUSE FARTHER WNW INTO ERN CO. SECONDARY/REINFORCING FRONT NOW EVIDENT FROM ERN MT SEWD ACROSS NERN NEB SHOULD BECOME NEARLY STATIONARY OVER NRN HIGH PLAINS THROUGH MOST OF PERIOD...AND NEARLY COLOCATED WITH LEE TROUGH IN MT. ...INTERIOR NWRN CONUS... AS HEIGHTS FALL AND GRADIENTS TIGHTEN ACROSS THIS REGION...DEEP-LAYER VERTICAL SHEAR PROFILES ARE EXPECTED TO BECOME FAVORABLE FOR SEVERE DURING AFTERNOON IN TANDEM WITH PEAK SFC WARMTH. NEARLY STRAIGHT LOW-MIDDLE LEVEL HODOGRAPHS ARE PROGGED...RESULTING FROM LOW LEVEL FLOW WITH WEAK SPEEDS BUT PRONOUNCED VEERING THAT TRANSITIONS TO 50-60 KT SSWLY FLOW IN 400-600 MB LAYER...YIELDING ABOUT 50 KT EFFECTIVE SHEAR. MODIFIED ETA/WRF SOUNDINGS SUGGEST SFC TEMPS LOW 70S AND DEW POINTS LOW 50S F WILL RESULT IN WELL MIXED BOUNDARY LAYERS WITH LITTLE OR NO CINH...INVERTED-V THERMODYNAMIC PROFILES IN SUBCLOUD LAYER...AND 600-1200 J/KG MLCAPE. THESE FACTORS SUPPORT BOTH BOW AND SUPERCELL POTENTIAL...WITH DAMAGING GUSTS AND LARGE HAIL. MAIN CONCERN FOR CONVECTIVE COVERAGE AND ORGANIZATION IS STRENGTH OF AFTERNOON HEATING GIVEN POTENTIAL FOR MID/HIGH LEVEL CLOUDS STREAMING NWD FROM VICINITY OF LOW APCHG CA. SVR THREAT SHOULD DIMINISH ONCE EVENING COOLING BEGINS TO STABILIZE PRECONVECTIVE BOUNDARY LAYER...AND AS ACTIVITY MOVES INTO MORE STABLE AMBIENT AIR MASS FARTHER NE. ...MT... ANOTHER EPISODE OF STRONG-SEVERE TSTMS IS POSSIBLE DURING AFTERNOON INTO EARLY EVENING...RESULTING FROM ACTIVITY INITIATING INVOF HIGHER TERRAIN OF SRN/WRN MT MID-LATE AFTERNOON. TSTMS MAY ORGANIZE INTO ONE OR MORE OUTFLOW-DOMINANT BANDS OR CLUSTERS...FORWARD PROPAGATING WITH MAIN THREAT BEING DAMAGING WIND. ALTHOUGH HEIGHTS ARE EXPECTED TO RISE GRADUALLY THROUGHOUT PERIOD OVER THIS REGION AS MEAN RIDGE AMPLIFIES...STRONG SFC HEATING AND WEAKENING CINH SHOULD SUPPORT AFTERNOON TSTM DEVELOPMENT. FAVORABLE DEEP-LAYER SHEAR PROFILES ARE EXPECTED WITH 40-50 KT OVER NRN PORTION OUTLOOK AREA...TRENDING TO ABOUT 35 KT AND LESS S OF MT/WY BORDER. SVR POTENTIAL IS EXPECTED TO DIMINISH MARKEDLY DURING EVENING AS FOREGOING BOUNDARY LAYER DIABATICALLY COOLS...AND AS ACTIVITY MOVES INTO PROGRESSIVELY LESS BUOYANT AIR MASS E OF SFC FRONT. ...CENTRAL PLAINS TO SC COAST... AS GREAT LAKES UPPER LOW EJECTS...HEIGHTS ARE FCST TO RISE ACROSS MOST OF CENTRAL/SERN CONUS THROUGHOUT PERIOD. CORRESPONDING DECREASE IN HEIGHT GRADIENT ALOFT...AND RELATED WEAKENING OF BOTH LARGE SCALE SUPPORT AND DEEP-LAYER KINEMATIC FIELDS WITH TIME -- INDICATE MORE CONDITIONAL/DISORGANIZED SEVERE POTENTIAL THIS PERIOD OVER MOST OF THIS CORRIDOR. HOWEVER...WILL MAINTAIN MRGL THRESHOLD PROBABILITIES FOR CATEGORICAL SLGT RISK ACROSS SUBSET OF THIS CORRIDOR...FROM S-CENTRAL KS TO NWRN TN -- COMBINING 1. CONDITIONAL DIURNAL RISK OF WIND AND HAIL INVOF FRONT WITH 2. SOMEWHAT HIGHER CONFIDENCE BUT LOWER MAGNITUDE HAIL THREAT AFTER DARK N OF FRONT. VEERING WIND PROFILES WITH HEIGHT WILL CONTINUE DESPITE WEAKENING LOW-MIDLEVEL SPEEDS...SUPPORTING POTENTIAL FOR STORM ORGANIZATION WITH ANY ACTIVITY THAT DEVELOPS. MIDLEVEL LAPSE RATES ACROSS THIS REGION SHOULD REMAIN RELATIVELY STEEP -- 7.5-8.5 DEG C/KM -- IN SUPPORT OF FAVORABLE BUOYANCY. AFTERNOON MLCAPES ALONG FRONT...AND LATE EVENING ELEVATED MUCAPES FARTHER N...SHOULD BE ENHANCED BY LOW LEVEL MOIST AXIS WITH VALUES OF EACH AROUND 1000-1500 J/KG. ...CENTRAL HIGH PLAINS... WIDELY SCATTERED TSTMS IN LOOSELY ORGANIZED CLUSTERS MAY EVOLVE DURING LATE AFTERNOON AND EVENING ACROSS HIGH PLAINS FROM NERN WY TO ERN CO/WRN KS...SOME OF WHICH MAY PRODUCE GUSTS NEAR SEVERE LIMITS. AFTERNOON INITIATION WILL BE AIDED BY ELY/UPSLOPE COMPONENT OF SFC FLOW...AMIDST WEAK CINH CAUSED BY AT LEAST MRGL SFC MOISTURE AND STRONG HEATING OF ELEVATED TERRAIN. VERY WEAK LOW/MIDLEVEL FLOWS AND DEEP-LAYER SHEAR PROFILES ARE EXPECTED TO LIMIT POTENTIAL FOR SUSTAINED/WELL-ORGANIZED SVR...THOUGH DEEPLY MIXED BOUNDARY LAYERS WILL SUPPORT STRONG/POSSIBLY SVR OUTFLOW WINDS IN SOME LOCALES. ..EDWARDS/GRAMS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 12:56:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 08:56:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211253 SWODY1 SPC AC 211251 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 AM CDT SUN MAY 21 2006 VALID 211300Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SE KS INTO THE TN VLY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL HI PLNS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER INTERIOR PARTS OF THE PAC NW/MT... ...SYNOPSIS... RCKYS RIDGE EXPECTED TO AMPLIFY SLIGHTLY AS IT SHIFTS E INTO THE HI PLNS BETWEEN NOW AND MONDAY...LARGELY IN RESPONSE TO DEEPENING OF UPR LOW W OF BC. DEEPENING OF BC LOW SHOULD DRIVE UPR SYSTEM NOW OFF THE CNTRL CA CST SE TOWARD SAN DIEGO BY EARLY MONDAY...AND MAINTAIN DEEP SSWLY FLOW OVER THE FAR WEST. AT THE SAME TIME... SYSTEM THAT CROSSED THE UPR GRT LKS YESTERDAY WILL REINFORCE EXISTING TROUGH OVER THE NORTHEAST. ASSOCIATED COLD FRONT SHOULD CONTINUE SW INTO THE LWR MO/MID MS VLYS...AND S/SE ACROSS THE OH VLY AND MID ATLANTIC STATES. THE FRONT SHOULD EVENTUALLY MERGE WITH WEAKER ONE NOW EXTENDING FROM CNTRL KS ESE INTO THE TN VLY. ...KS/MO E/SE INTO TN VLY... WHILE UPR RIDGE WILL AMPLIFY SOMEWHAT OVER THE HI PLNS...GLANCING INFLUENCE OF GRT LKS SPEED MAX WILL MAINTAIN 25-30 KT MID LEVEL WNWLY FLOW ABOVE WEAK FRONT STALLED FROM KS/SRN MO ESE INTO THE TN VLY. MODERATE SURFACE HEATING...RELATIVELY STEEP MID LEVEL LAPSE RATES /7.5-8.5 DEG C PER KM/...FAIRLY MOIST AIR /WARM SECTOR DEWPOINTS IN THE LOW 60S/ AND FRONTAL CONVERGENCE TOGETHER SHOULD SUPPORT RENEWED STORM DEVELOPMENT ALONG THE BOUNDARY BY MID TO LATE AFTERNOON. THIS POTENTIAL APPEARS MOST LIKELY FROM SE KS INTO SW MO...WHERE A RELATIVE MAXIMUM IN LOW LEVEL INFLOW SHOULD EXIST INVOF OUTFLOW BOUNDARIES LEFT BY OVERNIGHT STORMS. MORE WIDELY SCATTERED/ LESS SUSTAINED ACTIVITY SHOULD PREVAIL FARTHER E/SE ALONG FRONT... FROM THE TN VLY TO THE SC CST. 30-35 KT DEEP NWLY SHEAR SHOULD BE SUFFICIENT FOR ORGANIZED/ SUSTAINED STORMS AND POSSIBLE SUPERCELLS WITH HAIL/HIGH WIND... ESPECIALLY GIVEN ENHANCED DIRECTIONAL COMPONENT INVOF FRONT. ADDITIONAL STORMS MAY FORM N OF BOUNDARY IN MO TONIGHT/EARLY MONDAY AS NOCTURNAL STRENGTHENING/VEERING OF LLJ...AND AFOREMENTIONED MERGING OF FRONTS...ENHANCE WAA ACROSS THE REGION. ...CNTRL HI PLNS... WIDELY SCATTERED TSTMS THAT EVOLVE INTO LOOSELY ORGANIZED CLUSTERS WITH A THREAT FOR HIGH WIND MAY FORM LATE THIS AFTERNOON/EARLY TONIGHT FROM NE CO INTO ERN WY/THE NEB PANHANDLE. INITIATION WILL BE SUPPORTED BY ELY/UPSLOPE SFC FLOW...DUE LARGELY TO STRONG HEATING OF ELEVATED TERRAIN. SLOWLY RISING HEIGHTS ALOFT AND WEAK LOW LEVEL WINDS SHOULD LIMIT OVERALL STORM STRENGTH. BUT 25+ KT MID LEVEL WNW FLOW AND VERY DEEPLY MIXED BOUNDARY LAYER ENVIRONMENT WILL SUPPORT STRONG STORM OUTFLOW AND UPSCALE GROWTH INTO CLUSTERS. ...INTERIOR PAC NW INTO MT... WATER VAPOR IMAGERY AND RUC 500 MB VORT ANALYSIS SHOW A WEAK IMPULSE OVER NE NV THAT SHOULD CONTINUE NNE ACROSS SRN/ERN ID THROUGH MIDDAY...AND INTO N CNTRL MT BY THIS LATE AFTERNOON. THIS FEATURE...COUPLED WITH SURFACE HEATING...OROGRAPHIC ASCENT AND WEAKLY CONVERGENT LOW LEVEL FLOW...MAY SUPPORT ANOTHER ROUND OF STRONG TO SEVERE STORMS IN CNTRL MT. LARGE TEMP-DEWPOINT SPREADS AND MODERATE UNIDIRECTIONAL CLOUD LAYER FLOW SUGGEST MAIN SEVERE THREATS WILL BE WIND AND MARGINALLY SEVERE HAIL. FARTHER W...A CONDITIONAL RISK FOR STRONG/POSSIBLY SEVERE DIURNAL STORMS WILL EXIST IN MORE STRONGLY SHEARED UNIDIRECTIONAL WIND ENVIRONMENT OVER ERN/NRN ORE AND SE WA/WRN ID. MODIFIED ETA/WRF SOUNDINGS WITH SFC TEMPS IN THE LOW 70S AND DEWPOINTS IN THE LOW 50S F YIELD WELL-MIXED BOUNDARY LAYERS WITH LITTLE OR NO CINH...INVERTED-VEE SUBCLOUD LAYER THERMODYNAMIC PROFILES...AND ABOUT 1000 J/KG MLCAPE. COUPLED WITH 40+ KT DEEP SLY FLOW ON ERN FRINGE OF OFFSHORE TROUGH...SUCH A SETUP WOULD SUPPORT SUSTAINED STORMS AND POSSIBLE SUPERCELLS. ASSOCIATED EMBEDDED BOWS WOULD HAVE THE POTENTIAL FOR BOTH HIGH WIND AND HAIL. A MAJOR UNCERTAINTY REMAINS...HOWEVER...REGARDING CONVECTIVE COVERAGE AS LARGE SCALE FORCING FOR ASCENT SHOULD REMAIN WEAK...AND MID/HIGH LEVEL CLOUDS WILL LIMIT LOW LEVEL HEATING. SEEMS PRUDENT ATTM TO MAINTAIN A LOW PROBABILITY RISK FOR SEVERE IN THIS AREA UNTIL IT IS CLEAR THAT STORMS WILL INDEED NOT FORM. ..CORFIDI/GRAMS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 16:29:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 12:29:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211614 SWODY1 SPC AC 211613 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1113 AM CDT SUN MAY 21 2006 VALID 211630Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN KS/NERN OK TO THE SC COAST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL HIGH PLAINS... ...TN VALLEY TO THE SOUTHEASTERN U.S. COAST... SURFACE FRONT REMAINS IN PLACE FROM THE SERN NC COAST WNWWD INTO THE MO BOOTHEEL REGION TODAY...WITH MODERATE TO STRONG WNWLY FLOW ALOFT PERSISTING ALONG THIS BOUNDARY. AIR MASS HAS BEEN OVERTURNED THE PAST COUPLE DAYS AND INSTABILITY WILL NOT BE AS STRONG AS YESTERDAY...THOUGH STRONG HEATING WILL AGAIN OCCUR WITHIN THE WARM SECTOR. AFTERNOON TEMPERATURES RISING THROUGH THE 80S AND SURFACE DEW POINTS HOLDING IN THE LOWER 60S ARE EXPECTED TO SUPPORT MODEST CAPE WITH MLCAPE FROM 1000-1500 J/KG. IN ADDITION...WEAK IMPULSE AIDING CONVECTIVE CLUSTER NOW MOVING INTO SERN TN WILL CONTINUE SEWD INTO SC AGAIN TODAY. GIVEN 40-50 KT EFFECTIVE SHEAR STILL IN PLACE...ACTIVITY MAY INCREASE IN COVERAGE AND INTENSITY AS STORMS SPREAD SEWD ACROSS THE SRN APPALACHIANS THIS AFTERNOON. SEVERITY WILL LIKELY NOT BE AS ROBUST AS YESTERDAY. HOWEVER...ENVIRONMENT STILL APPEARS SUPPORTIVE OF A FEW ORGANIZED CLUSTERS/SUPERCELLS SHOULD STORMS ROOT INTO MODEST MIXED-LAYER CAPE DURING THIS AFTERNOON. ...SERN KS ACROSS THE OZARK REGION INTO THE MID SOUTH... MCV FROM SMALL MCS WHICH ERODED ACROSS SWRN KS OVERNIGHT WAS EVIDENT ON SATELLITE IMAGERY OVER S-CENTRAL KS THIS MORNING. SMALL SCALE ENHANCEMENT OF LOW TO MID TROPOSPHERIC WINDS AND DEEP ASCENT SHOULD SUPPORT INCREASED CLUSTER OF STRONG TO SEVERE THUNDERSTORMS INTO SERN KS/FAR NERN OK AND SWRN MO AS CAP BREAKS THIS AFTERNOON. AIR MASS WILL LIKELY BECOME MODERATE TO STRONGLY UNSTABLE WITH STRONG HEATING ALONG AND SOUTH OF EFFECTIVE SURFACE FRONT NOW EXTENDING FROM SWRN MO WWD INTO FAR S-CENTRAL KS AND WSWWD ACROSS NWRN OK THIS MORNING. GIVEN LOCAL ENHANCEMENT OF DEEP LAYER SHEAR...STORMS MAY DEVELOP INTO SUPERCELLS THOUGH ITS MORE LIKELY STORMS WILL INCREASE INTO A CLUSTER/MCS WITH THREATS OF LARGE HAIL AND DAMAGING WINDS AS ACTIVITY MOVES SLOWLY SEWD THROUGH THE EVENING. ...CENTRAL HIGH PLAINS... RIDGING ALOFT WILL BUILD ACROSS THE CENTRAL ROCKIES TODAY. HOWEVER...SUFFICIENT WLY FLOW WILL PERSIST ACROSS NRN CO INTO ERN WY FOR MODEST DEEP LAYER SHEAR...WHERE FORECAST SOUNDINGS MAINTAIN 35-40 KT EFFECTIVE SHEAR. SURFACE WINDS ARE FORECAST BY ALL THE SHORT-TERM MODELS TO BACK TO SELY ACROSS THE CENTRAL HIGH PLAINS WITH WEAK LOW CENTER/TROUGH DEVELOPING INTO CENTRAL WY. THIS SHOULD SUSTAIN LOW 50F SURFACE DEW POINTS ALONG AND JUST EAST OF THE HIGHER TERRAIN FROM NRN CO INTO MUCH OF ERN WY. GIVEN STRONG HEATING...AIR MASS SHOULD BECOME MODERATELY UNSTABLE BY MID TO LATE AFTERNOON WITH INCREASING CONVECTION OVER HIGHER TERRAIN AND/OR INVOF LEE TROUGH. ACTIVITY WILL LIKELY PERSIST FOR SEVERAL HOURS WITH THREATS OF LARGE HAIL AND DAMAGING WINDS AS IT SHIFTS EWD OVER THE HIGH PLAINS LATE TODAY/THIS EVENING. CONSOLIDATION INTO A SMALL MCS IS POSSIBLE ALONG NOSE OF MODEST SLY H85 WIND MAX ACROSS WRN NEB LATER THIS EVENING. THOUGH ISOLATED SEVERE MAY DEVELOP INTO THE NRN HIGH PLAINS AND SWD INTO PORTIONS OF WEST TX ALONG LEE TROUGH TODAY...OVERALL SEVERE THREAT WARRANTS ONLY LOW PROBABILITIES ACROSS THESE AREAS. ...NRN INTERMOUNTAIN REGION... COMPLEX CONVECTIVE SCENARIO ACROSS THIS AREA TODAY AS RIDGE BUILDS OVER THE ROCKIES AND A STRONG UPPER LOW STAYS OFF THE CA COAST. CONSIDERABLE CLOUDINESS HAS OVERSPREAD MUCH OF THE NWRN INTERMOUNTAIN REGION THIS MORNING WHICH WILL LIMIT INSTABILITY AND RESULTANT THUNDERSTORM POTENTIAL TODAY. SHEAR WILL REMAIN MODEST AND SUPPORT SOME ORGANIZATION WITH ANY STORM WHICH CAN BE SUSTAINED OFF HIGHER TERRAIN...THOUGH OVERALL SEVERE THREAT APPEARS MARGINAL ATTM. ...WRN MT INTO THE NRN HIGH PLAINS... HEATING WILL BE ROBUST OVER THE NRN ROCKIES INTO CENTRAL MT AHEAD OF A SHORTWAVE TROUGH NOW EJECTING NWD OUT OF NV TODAY. THIS SYSTEM WILL LIKELY MAINTAIN SUFFICIENT MID LEVEL MOISTURE/LIFT FOR INCREASED THUNDERSTORMS OVER THE NRN ROCKIES THIS AFTERNOON WHICH WILL SPREAD NEWD ACROSS CENTRAL MT LATER TODAY AND THIS EVENING. HOWEVER...AIR MASS IS DRIER TODAY OVER MT WITH PW/S AT TFX LESS THAN .5 INCH AT 12Z. THUS...INSTABILITY WILL LIKELY BE MARGINAL AND WILL LIMIT SEVERITY WITH EXPECTED STORM CLUSTER/S TODAY. ISOLATED DAMAGING WINDS/LARGE HAIL MAY STILL ACCOMPANY STRONGER STORMS...THOUGH APPEARS OVERALL THREAT WARRANTS LOWER PROBABILITIES THAN EARLIER FORECAST. ..EVANS/GUYER.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 20:03:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 16:03:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 212000 SWODY1 SPC AC 211958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT SUN MAY 21 2006 VALID 212000Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL PLAINS...OZARK PLATEAU...TN VALLEY AND SRN ATLANTIC SEABOARD... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL AND NRN HIGH PLAINS... ...SRN ATLANTIC SEABOARD/SRN APPALACHIANS AND TN VALLEY... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL TROUGH OVER THE ERN SEABOARD WITH AN MCS DEVELOPING ACROSS WRN SC. AT THE SFC...A NEARLY STATIONARY FRONT IS LOCATED FROM TN EXTENDING EWD ACROSS NRN SC. ALONG AND SOUTH OF THE BOUNDARY...SFC DEWPOINTS ARE IN THE 60S F WITH A POCKET OF MODERATE INSTABILITY CURRENTLY LOCATED IN NRN SC WHICH SHOULD SUSTAIN THE DEVELOPING MCS THIS AFTERNOON. IN ADDITION...OBJECTIVE ANALYSIS SHOWS 0-6 KM SHEAR VALUES EXCEEDING 30 KT NEAR AND TO THE NORTH OF THE BOUNDARY. AS A RESULT..THE ENVIRONMENT SHOULD BE SUPPORTIVE OF SUPERCELLS ESPECIALLY AS STORMS ORGANIZE AND MOVE INTO THE STRONGER INSTABILITY IN THE COASTAL PLAINS. STORM DEVELOPMENT WILL ALSO BE LIKELY FURTHER WEST ACROSS THE TN VALLEY LATER THIS AFTERNOON AND EARLY THIS EVENING. THE STRONGER CELLS SHOULD DEVELOP A POTENTIAL FOR LARGE HAIL AND ISOLATED WIND DAMAGE ACROSS TN...FAR NRN MS AND FAR NRN AL WHERE MLCAPE VALUES CURRENTLY RANGE FROM 1000-1500 J/KG AND MODERATE VERTICAL SHEAR EXISTS. ...CNTRL PLAINS AND OZARK PLATEAU... WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A SHORTWAVE TROUGH AND PLUME OF MID-LEVEL MOISTURE OVER CNTRL KS. AT THE SFC...A NEARLY STATIONARY FRONT IS LOCATED ACROSS ERN KS AND SRN MO. ALONG AND SOUTH OF THE BOUNDARY...AN AXIS OF INSTABILITY EXISTS WITH MLCAPE VALUES RANGING FROM 1500-2500 J/KG. IN ADDITION...REGIONAL PROFILERS SHOW MODERATE VERTICAL SHEAR PROFILES ACROSS MUCH OF ERN KS EXTENDING ESEWD ACROSS THE OZARK PLATEAU. AS A RESULT...THE ENVIRONMENT SHOULD BE SUPPORTIVE OF SUPERCELLS AS STORMS INITIATE AHEAD OF THE SHORTWAVE TROUGH ALONG THE BOUNDARY AND MOVE SEWD INTO THE INSTABILITY AXIS LATE THIS AFTERNOON. STEEP MID-LEVEL LAPSE RATES WILL BE FAVORABLE FOR LARGE HAIL. THE WIND DAMAGE POTENTIAL SHOULD ALSO INCREASE AS LOW-LEVEL LAPSE RATES STEEPEN AND THE STORMS INCREASE IN COVERAGE BY EARLY EVENING. ...CNTRL AND NRN HIGH PLAINS... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL RIDGE IN PLACE ACROSS THE HIGH PLAINS. SCATTERED THUNDERSTORMS ARE DEVELOPING UNDER THE RIDGE ALONG AND EAST OF A LEE SFC TROUGH. DEWPOINTS ARE IN THE 50S F WITH AN AXIS OF MODERATE INSTABILITY EXTENDING NNWWD FROM WRN KS ACROSS WRN NEB...FAR NE CO AND ERN WY. IN ADDITION TO THE INSTABILITY...REGIONAL PROFILERS SHOW SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. AS STORMS INCREASE IN COVERAGE AND MOVE EWD INTO THE INSTABILITY AXIS...THE SEVERE POTENTIAL SHOULD INCREASE. STEEP LAPSE RATES SHOULD FAVOR LARGE HAIL AND ISOLATED WIND DAMAGE AS THE PRIMARY SEVERE THREAT. FURTHER NORTHWEST ACROSS THE NRN ROCKIES...SCATTERED THUNDERSTORMS SHOULD DEVELOP THIS AFTERNOON AND MOVE NEWD ACROSS THE REGION. ALTHOUGH OBJECTIVE ANALYSIS SHOWS MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES IN PLACE ACROSS MOST OF THE REGION...INSTABILITY IS WEAKER FROM CNTRL MT EXTENDING WWD ACROSS ID. THIS WEAKNESS IN INSTABILITY SHOULD KEEP ANY SEVERE THREAT MARGINAL LATE THIS AFTERNOON AND EARLY THIS EVENING. ..BROYLES.. 05/21/2006  From swody1 at goshenarc.org Mon May 22 01:06:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 21:06:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220103 SWODY1 SPC AC 220101 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0801 PM CDT SUN MAY 21 2006 VALID 220100Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE OZARK REGION ESE INTO TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS WRN PARTS OF THE NRN/CENTRAL PLAINS... ...OZARK REGION ESE TO TN VALLEY/SRN APPALACHIANS... QUASI-STATIONARY BOUNDARY REMAINED LOCATED FROM THE SRN APPALACHIANS WNWWD THROUGH SRN-WRN TN INTO NRN AR TO NORTH CENTRAL OK BEFORE BECOMING A LITTLE MORE DIFFUSE INTO THE SRN HIGH PLAINS. WATER VAPOR IMAGERY INDICATED SEVERAL WEAK SHORT WAVE TROUGHS/MCVS ALONG THE EXTENT OF THIS BOUNDARY WITH ONE LOCATED OVER THE TN VALLEY AND TWO UPSTREAM OVER WRN AR AND NERN OK/SERN KS. ASCENT ASSOCIATED WITH THESE FEATURES AS THEY TRACK ESE COMBINED WITH LOW-LEVEL WAA AND AIR MASS REMAINING MODERATELY UNSTABLE THROUGH 06-09Z ALONG THE SURFACE BOUNDARY WILL SUPPORT ADDITIONAL TSTMS. GREATEST THUNDERSTORM COVERAGE AND SEVERE POTENTIAL IS EXPECTED TO EXTEND FROM SRN MO/NRN AR INTO MIDDLE TN/FAR NRN AL...AND POSSIBLY NWRN GA THROUGH 12Z. EFFECTIVE SHEAR/INSTABILITY WILL FAVOR HAIL/ STRONG WIND GUSTS WITH ADDITIONAL STORMS. ...WRN PART OF THE NRN/CENTRAL PLAINS... THUNDERSTORMS OVER CENTRAL/ERN MT AND SWD FROM FAR ERN WY INTO WRN NEB/NWRN KS ARE BEING AIDED BY LARGE SCALE ASCENT ASSOCIATED WITH A COUPLE OF SHORT WAVE TROUGHS OVER MT AND WY. THIS ASCENT COMBINED WITH INCREASING WAA PER A STRENGTHENING SLY LLJ OVER WRN KS AND SSELY LLJ ALONG NRN HIGH PLAINS EXPECTED TO MAINTAIN POTENTIAL FOR ADDITIONAL THUNDERSTORMS THROUGH 06-09Z. GREATEST LIKELIHOOD FOR UPSCALE GROWTH INTO AN MCS IS EXPECTED WITH SRN CLUSTER OF STORMS OVER SWRN NEB/FAR NWRN KS WITH ACTIVITY SPREADING ESE OVERNIGHT ALONG INSTABILITY AXIS. STRONG WIND GUSTS AND HAIL ARE EXPECTED TO BE THE PRIMARY SEVERE THREATS. ...OK/TX PANHANDLES SWD THROUGH W TX... ISOLATED SEVERE STORMS WILL REMAIN POSSIBLE FOR THE NEXT FEW HOURS ACROSS WEST TX INCLUDING THE PANHANDLE...WHERE 00Z SOUNDINGS INDICATED A DEEPLY MIXED SUB-CLOUD LAYER SUPPORTIVE OF STRONG DOWNDRAFTS. DIABATIC COOLING SHOULD WEAKEN AVAILABLE INSTABILITY AND REDUCE THE LIKELIHOOD FOR SEVERE STORMS LATER THIS EVENING. ...INTERIOR PACIFIC NORTHWEST... INCREASING SLY MID LEVEL FLOW ACROSS ERN ORE/WA/ID/FAR WRN MT AND ASSOCIATED LARGE SCALE ASCENT WITHIN EXIT REGION OF THIS JET EXPECTED TO SUPPORT ADDITIONAL POTENTIAL FOR THUNDERSTORMS THROUGH THE EVENING. STRONG DEEP LAYER SHEAR WILL SUPPORT SOME STORM ORGANIZATION...BUT WEAK INSTABILITY SHOULD LIMIT SEVERE COVERAGE. ...ERN NEW ENGLAND... THE PORTION OF THE STRONGLY FORCED LINE OF LOW-TOPPED CONVECTION THAT HAD PRODUCED SOME SEVERE STORMS ACROSS NEW ENGLAND DURING THE LATE AFTERNOON HAS MOVED EWD OFFSHORE THE MA COAST...THUS LIMITING THE POTENTIAL FOR ADDITIONAL SEVERE STORMS. OVERALL PROBABILITY FOR THUNDERSTORMS WILL ALSO DECREASE OVERNIGHT AS THE ATTENDANT STRONG MID LEVEL IMPULSE...NOW CENTERED OVER NEW ENGLAND...TRACKS EWD TOWARD NOVA SCOTIA. ..PETERS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 06:04:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 02:04:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220601 SWODY1 SPC AC 220559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT MON MAY 22 2006 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE INTERIOR NW EWD ACROSS MT THEN SEWD TO THE CENTRAL HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE TN VALLEY TO NRN-ERN GA AND PARTS OF SRN SC... ...SYNOPSIS... STRONG SHORT WAVE TROUGH...CURRENTLY LOCATED JUST W OF SRN CA PER WATER VAPOR IMAGERY...IS EXPECTED TO EJECT NEWD AS A NEGATIVELY TILTED TROUGH ACROSS THE SWRN STATES REACHING THE FOUR CORNERS REGION BY 23/00Z...THEN INTO THE CENTRAL ROCKIES/HIGH PLAINS BY 12Z TUESDAY. ALTHOUGH THIS TROUGH SHOULD DE-AMPLIFY SOME AS IT TRACKS NEWD INTO THE PLAINS UPPER RIDGE...60-90 METER 500 MB HEIGHT FALLS WILL BE MAINTAINED ALONG ITS PATH. THE EJECTION OF THIS TROUGH IS IN RESPONSE TO UPSTREAM HEIGHT FALLS UNDERWAY 300-500 MILES W OF NRN CA/ORE...AS THE NERN PACIFIC DEEP UPPER LOW SETTLES SWD PRIOR TO 12Z TODAY. IN THE EAST...LONG WAVE TROUGH WILL REMAIN OVER THIS REGION WITH SRN PERIPHERY OF STRONGEST MID LEVEL FLOW EXTENDING FROM THE WRN GREAT LAKES SEWD ACROSS THE CENTRAL APPALACHIANS TO MID ATLANTIC STATES/ CAROLINAS. QUASI-STATIONARY SURFACE BOUNDARY SHOULD EXTEND FROM SC COAST NWWD THROUGH TN VALLEY INTO NRN AR AND ALONG THE OK/KS BORDER WHERE IT SHOULD BE MORE DIFFUSE. ...CENTRAL/NRN HIGH PLAINS... SSELY LOW-LEVEL FLOW WILL ALLOW MOISTURE TO CONTINUE TO RETURN NNWWD ACROSS THE CENTRAL/NRN PLAINS THIS FORECAST PERIOD. WEAK HEIGHT FALLS EXPECTED IN ADVANCE OF MAIN SWRN TROUGH AND POTENTIALLY ASSOCIATED WITH A WEAK IMPULSE TRACKING NEWD ACROSS THIS REGION WILL LIKELY AID IN THUNDERSTORMS THIS AFTERNOON FROM ERN CO TO ERN MT. THIS ACTIVITY WILL BE ALONG THE WRN EDGE OF THE DEEP MOISTURE WHERE MIXING AND SURFACE HEATING SHOULD WEAKEN THE CAP BY MID-LATE AFTERNOON. DEEP LAYER SHEAR WILL INITIALLY NOT BE STRONG...BUT EXPECTED TO INCREASE THIS EVENING/TONIGHT AS MID LEVEL WIND MAX WITH STRONGER SHORT WAVE TROUGH MOVES INTO CO. THUS...DESPITE SOME DECREASE IN INSTABILITY AFTER 00Z...STRONG ASCENT SPREADING NEWD WITH APPROACH OF UPPER TROUGH/PACIFIC COLD FRONT SHOULD ALLOW SEVERE THREAT TO PERSIST THIS EVENING/TONIGHT. ...INTERIOR NW INTO WRN MT... DEEP UPPER LOW REMAINING OVER THE NERN PACIFIC WILL MAINTAIN MODERATE SLY MID LEVEL FLOW ACROSS THIS REGION FOR MUCH OF THE FORECAST PERIOD. THE AMOUNT OF CLOUD COVER EXPECTED ACROSS THIS REGION TODAY MAY LIMIT THE DEGREE OF SURFACE HEATING. HOWEVER... RESIDUAL LOW-LEVEL MOISTURE BENEATH STEEP MID LEVEL LAPSE RATES SHOULD RESULT IN MLCAPE VALUES RANGING FROM 500-1000 J/KG...WITH THE HIGHER VALUES IN LOCATIONS WITH STRONGER SURFACE HEATING. DESPITE THE POTENTIAL FOR WEAKER INSTABILITY...LARGE SCALE ASCENT ASSOCIATED WITH A SHORT WAVE TROUGH ROTATING AROUND THE ERN PERIPHERY OF THE OFFSHORE UPPER LOW EXPECTED TO BE SUFFICIENT FOR THUNDERSTORMS TO DEVELOP BY THIS AFTERNOON. DEEP LAYER SHEAR WILL BE MORE THAN ADEQUATE TO SUPPORT ORGANIZED STORMS...WITH STRONG WIND GUSTS AND HAIL THE PRIMARY THREATS FROM THIS AFTERNOON INTO THE EVENING. ...TN VALLEY SE TO ERN GA/PARTS OF SRN SC... A COUPLE OF WEAK MID LEVEL IMPULSES ARE EXPECTED TO TRACK ESEWD ACROSS THE TN VALLEY TOWARD GA/SC TODAY. ALTHOUGH LOW LEVEL WINDS/CONVERGENCE SHOULD BE WEAK ALONG THE SURFACE BOUNDARY... ASCENT WITH THESE IMPULSES...MODERATE INSTABILITY AND 35-40 KT 0-6 KM SHEAR WILL LIKELY SUPPORT A FEW SEVERE STORMS. HAIL AND STRONG WIND GUSTS WILL BE THE PRIMARY THREAT...WHILE WEAK LOW-LEVEL WINDS SHOULD TEND TO MINIMIZE THE TORNADO POTENTIAL. ...LOWER CO RIVER VALLEY NEWD INTO CENTRAL/SRN ROCKIES... STRONG HEIGHT FALLS/FORCING EXPECTED TO SPREAD ACROSS THIS REGION TODAY AHEAD OF UPPER TROUGH. THIS COMBINED WITH STRONG SURFACE HEATING/OROGRAPHIC ASCENT EXPECTED TO SUPPORT WIDESPREAD CONVECTION ALONG THE TRACK OF THE UPPER TROUGH. HOWEVER...WEAK INSTABILITY SHOULD PRECLUDE A GREATER SEVERE THREAT. STEEP LAPSE RATES AND INCREASING DEEP LAYER SHEAR FROM W-E ACROSS THIS REGION SHOULD SUPPORT A LOW PROBABILITY FOR SEVERE HAIL/STRONG WIND GUSTS. ..PETERS/GRAMS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 12:58:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 08:58:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221255 SWODY1 SPC AC 221254 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT MON MAY 22 2006 VALID 221300Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER A LARGE PART OF THE INTERMOUNTAIN WEST AND CNTRL RCKYS/HI PLNS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE TN VLY AND SOUTHEAST... ...SYNOPSIS... AN ACTIVE SEVERE WEATHER DAY EXPECTED OVER PARTS OF THE INTERMOUNTAIN REGION AND RCKYS TODAY AS STRONG SHORTWAVE TROUGH NOW OVER SRN CA/NRN BAJA IS EJECTED RAPIDLY NEWD BY DEEP LOW OFF THE BC CST. EJECTING SYSTEM WILL INDUCE LEE TROUGHING OVER THE CNTRL/NRN HI PLNS...WITH SURFACE LOW EXPECTED TO DEEPEN ALONG THE TROUGH OVER S CNTRL MT TONIGHT/EARLY TUESDAY. IN THE EAST...A SERIES OF IMPULSES WILL MAINTAIN BROADER SCALE TROUGH OVER THE GRT LKS/NEW ENG....WITH ASSOCIATED SURFACE FRONT REMAINING MORE OR LESS STATIONARY FROM THE TN VLY TO THE SC CST. ...FOUR CORNERS REGION INTO CNTRL RCKYS/CNTRL HI PLNS... SEVERAL BANDS OF TSTMS EXPECTED TO PRECEDE AND POSSIBLY ACCOMPANY SRN CA SYSTEM AS IT MOVES E/NE ACROSS THE SRN/ERN GRT BASIN AND INTO THE CNTRL RCKYS LATER TODAY/TONIGHT. GIVEN STRONG BACKGROUND WIND FIELD /500 MB SPEEDS INCREASING TO AROUND 50 KTS/...INVERTED VEE SOUNDINGS EXPECTED WITH DAYTIME HEATING...AND SUSTAINED FORCING FOR ASCENT...SOME OF THE STORM BANDS MAY CONTAIN BOTH LARGE AND SMALL SCALE BOWING SEGMENTS WITH HIGH WIND. DOWNSTREAM FROM THE MORE DYNAMICALLY-DRIVEN CONVECTION...OTHER STORMS EXPECTED TO FORM THIS AFTERNOON THROUGH TONIGHT IN CONFLUENT ...WEAKLY UPSLOPE ENVIRONMENT ALONG THE CO/SRN WY FRONT RANGE EWD INTO THE CNTRL HI PLNS OF ERN CO/SE WY AND THE NEB PANHANDLE. DEVELOPMENT MAY BE MODULATED...AND POSSIBLY ENHANCED...INVOF CONVECTIVE OUTFLOW/LOW LEVEL MOISTURE AXES LEFT BY OVERNIGHT MCS IN KS. GIVEN INCREASINGLY STRONG WIND FIELDS...AND PRESENCE OF SUBSTANTIAL DIRECTIONAL COMPONENT TO THE LOW LEVEL SHEAR...POTENTIAL WILL EXIST FOR SUPERCELLS WITH LARGE HAIL/HIGH WIND AND PERHAPS A COUPLE TORNADOES. THIS ACTIVITY LIKELY WILL BE OVERTAKEN BY FASTER MOVING STORMS ARRIVING FROM THE WRN/SRN CO. THE RESULTING CLUSTERS SHOULD CONTINUE GENERALLY E IN A DIMINISHING STATE INTO PARTS OF NRN KS AND WRN/CNTRL NEB EARLY TUESDAY. ...NRN INTERMOUNTAIN REGION... MODERATE SURFACE HEATING OF STRONGLY SHEARED ENVIRONMENT MAY YIELD ANOTHER DAY OF STRONG STORMS/POSSIBLE SUPERCELLS OVER WRN ID AND ERN WA/ORE. THIS CORRIDOR SHOULD EXPERIENCE THE STRONGEST/DEEPEST FORCING FOR ASCENT IN DEFORMATION ZONE BETWEEN EJECTING SYSTEM TO THE S...AND NEARLY STATIONARY LOW OFF THE BC/WA CST. SOME OF THESE STORMS MAY REMAIN STRONG INTO THE NIGHT IN NRN ID. ...TN VLY TO SC CST... ANOTHER ROUND OF STRONG TO SEVERE DIURNAL STORMS EXPECTED ALONG STALLED FRONT IN THE SOUTHEAST. BOUNDARY WILL REMAIN PARALLEL TO MODERATE DEEP WNWLY SHEAR. DETAILS OF CONVECTIVE EVOLUTION WILL ONCE AGAIN BE DOMINATED BY STORM-SCALE AND...POSSIBLY...ONCE AGAIN BY OROGRAPHIC FACTORS ASSOCIATED WITH THE SRN APLCNS. CLOUDS OVER THE SC MIDLANDS WILL LIMIT LOW LEVEL DESTABILIZATION IN THAT REGION. BUT AREA SOUNDINGS SUGGEST SUFFICIENT SHEAR/INSTABILITY TO SUPPORT DEVELOPMENT OF SUSTAINED...MULTICELL FORWARD-PROPAGATING CLUSTERS WITH HAIL/HIGH WIND...WITH INITIATION FAVORED IN SPOTS RECEIVING MORE SUN. ..CORFIDI/GRAMS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 16:40:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 12:40:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221628 SWODY1 SPC AC 221626 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1126 AM CDT MON MAY 22 2006 VALID 221630Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM JUST WEST OF THE ROCKIES EWD ACROSS THE HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE NRN INTERMOUNTAIN WEST AND NRN ROCKIES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SERN KS AND THE OZARK PLATEAU... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN APPALACHIANS ACROSS SC... ...ALONG/JUST WEST OF ROCKIES EWD ACROSS THE HIGH PLAINS... DEEP...NEGATIVELY-TILTED TROUGH WITH STRONGEST ENERGY NOW APPROACHING THE LOWER CO RIVER VALLEY WILL ENHANCE THUNDERSTORM POTENTIAL ACROSS MUCH OF THE WRN U.S. TODAY. DEEP SLY FLOW AND INCREASED MID LEVEL MOISTURE IS SUSTAINING WIDESPREAD CLOUDS OVER A LARGE PART OF THE GREAT BASIN INTO THE PAC NW WHICH WILL LIMIT HEATING AND INSTABILITY OVER THESE REGIONS. APPEARS JUST EAST OF THIS CLOUD SHIELD...INTO THE SRN ROCKIES AND ERN PORTIONS OF THE INTERMOUNTAIN WEST...HEATING WILL ALLOW STEEP LOW LEVEL LAPSE RATES TO DEVELOP UNDER MOISTENING MID LEVELS AND INCREASING LARGE SCALE ASCENT THIS AFTERNOON. TEMPERATURES ARE ALREADY APPROACHING 80F OVER WRN CO...WITH FURTHER HEATING THROUGH THE DAY. THUS...INCREASING THUNDERSTORMS WILL SPREAD A THREAT OF HAIL AND DAMAGING WINDS EWD INTO THE SRN/CENTRAL ROCKIES THROUGH THE EARLY EVENING. EAST OF THE ROCKIES...SELY WINDS AND BOUNDARY LAYER MOISTURE HAVE BECOME MORE FAVORABLE TODAY FOR SEVERE THUNDERSTORMS THAN THE PAST COUPLE DAYS FROM SERN MT INTO ERN NM. IN ADDITION...PRESSURE FALLS AND SSWLY WINDS ALOFT WILL STRENGTHEN LATER TODAY AHEAD OF APPROACHING UPPER TROUGH...INCREASING DEEP LAYER SHEAR AS FAR SOUTH AS ERN NM. THUS...INCREASING MLCAPE OVER THE HIGH PLAINS THROUGH THE AFTERNOON WILL BECOME MORE FAVORABLE FOR INTENSE THUNDERSTORMS PERSISTING EWD OVER THE HIGH PLAINS THROUGH THE EVENING. FORECAST SOUNDINGS INDICATE SHEAR ADEQUATE FOR SUPERCELLS...WITH TORNADO POTENTIAL INCREASING INTO NWRN KS/NERN CO/NEB PANHANDLE BY THE EARLY EVENING WHERE RUC DEVELOPS 40 KT SSELY LLJ BY 00Z. ISOLATED DAMAGING WINDS AND VERY LARGE HAIL MAY ALSO ACCOMPANY STRONGER CORES THIS EVENING. OVERALL EVOLUTION INTO SEVERAL CLUSTERS AND SMALL MCSS APPEARS LIKELY LATER THIS EVENING...ESPECIALLY INTO WRN KS/WRN NEB ALONG NOSE OF STRONGER SLY LLJ. ...FAR ERN ORE/ERN WA INTO WRN MT... THIN CLOUDS WITH SOME BREAKS ARE EVIDENT OVER PORTIONS OF WRN ID INTO FAR NERN ORE THIS MORNING. SHEAR WILL REMAIN QUITE STRONG OVER THIS REGION UNDER 45 KT SLY MID LEVEL WINDS AND MID LEVELS WILL COOL UNDER -16C H5 THERMAL TROUGH. THUS...EVEN MODEST HEATING WILL PROVIDE SUFFICIENT DESTABILIZATION FOR A FEW SEVERE THUNDERSTORMS OVER HIGHER TERRAIN AND NEAR SURFACE LOW/COLD FRONT MOVING EWD ACROSS NRN ID INTO WRN MT TODAY. ...SERN KS ACROSS THE OZARK PLATEAU... REFERENCE SWOMCD 932 FOR SHORT-TERM GUIDANCE ON THIS REGION. MUCH STRONGER HEATING/INSTABILITY TODAY AS COMPARED TO YESTERDAY AHEAD OF SLOW MOVING MCV NOW OVER S-CENTRAL KS. EXPECT WEAKLY SHEARED CLUSTER OF STRONG/SEVERE THUNDERSTORMS WILL EVOLVE AND REMAIN FOCUSED IMMEDIATELY AHEAD OF MCV AS IT TRACKS SLOWLY EWD ACROSS SERN KS INTO SWRN MO. LARGE HAIL AND DAMAGING WINDS MAY ACCOMPANY THIS ACTIVITY. ...TN INTO SC... SURFACE BOUNDARY REMAINS IN PLACE OVER THIS REGION AND SHOULD FOCUS THUNDERSTORMS LATER TODAY AS CAP WEAKENS...AS HAS BEEN THE CASE FOR A COUPLE DAYS NOW. HOWEVER...APPEARS WEAKER SHEAR WILL LIMIT ORGANIZED/SUSTAINED SEVERE THREAT OVER THE MID SOUTH AND TN RIVER VALLEY. SHEAR REMAINS STRONGER ALONG PORTION OF THE FRONT PERSISTING ACROSS SC...WHERE ERODING CLOUDS ARE NOW SUPPORTING ROBUST HEATING ONCE AGAIN. OVERALL THREAT MAY BE LESS THAN THE PAST TWO DAYS...THOUGH ENVIRONMENT WILL STILL FAVOR A FEW ORGANIZED CLUSTERS AS STORMS DEVELOP AND SPREAD ESEWD THROUGH THE EARLY EVENING. ..EVANS/GUYER.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 21:06:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 17:06:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 222101 SWODY1 SPC AC 222059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0359 PM CDT MON MAY 22 2006 VALID 222000Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLATEAU REGION.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL ROCKIES FROM SERN MT INTO NRN NM.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS CENTRAL AND SERN KS.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SC AND GA.... ...SYNOPSIS... NEGATIVELY TILTED MID/UPPER LEVEL TROUGH IS CURRENTLY MOVING NEWD OVER WRN/SCENTRAL NV ACCORDING TO LATEST WATER VAPOR SATELLITE LOOP. WIDESPREAD AREA OF THUNDERSTORMS EXTENDS FROM SERN WY SEWD/SWD THRU WRN CO INTO CENTRAL NM AS INDICATED ON LATEST LIGHTNING NETWORK. THIS ACTIVITY IS OCCURRING AHEAD OF SURFACE TROUGH/FRONTAL BOUNDARY WHICH IS EXPECTED TO ACCOMPANY THE MID/UPPER LEVEL TROUGH EWD/NEWD THROUGH THE REMAINDER OF THE PERIOD. ...CENTRAL AND SERN KS... MORNING CONVECTION AND ASSOCIATED MCV JUST E OF ICT IS MOVING SLOWLY EWD WITH NEW CONVECTION DEVELOPING RIGHT NEAR THE MCV. AIR MASS CONTINUES TO DESTABILIZE N-NE-E OF THE MCV WITH MLCAPE BETWEEN 1500-2000 J/KG. ALSO...CIRRUS CANOPY FROM CURRENT CONVECTION HAS RETARDED FURTHER DESTABILIZATION ESE AND S WHERE CAPPING INVERSION REMAINS. THUS...LOOKS LIKE CONTINUED THREAT FOR HAIL AND DAMAGING WINDS WILL BE FROM S CENTRAL INTO SERN KS...POSSIBLY INTO THE EXTREME WRN COUNTIES OF SWRN MO. ALSO ADDITIONAL STRONG/SEVERE THUNDERSTORMS COULD DEVELOP NWD BETWEEN HUT AND SLN...AND JUST S OF THE KS/OK BORDER FROM PNC TO NEAR GMJ. ...SERN MT SWD INTO E CENTRAL NM... STRONG/SEVERE THUNDERSTORMS WILL CONTINUE TO DEVELOP AHEAD OF NEGATIVELY TILTED TROUGH/ASSOCIATED SURFACE TROUGH/FRONTAL BOUNDARY. FORECAST SOUNDINGS SHOW INVERTED-V TYPE PROFILES WITH 700-500 MB LIFTED INDICES AROUND -4 ACROSS WRN CO INTO CENTRAL NM. IN ADDITION...MID LEVEL LAPSE RATES BETWEEN 7.5 TO 9C/KM ARE EXPECTED THIS AFTERNOON INDICATING THE THREAT FOR DOWNBURST WINDS AND POSSIBLY HAIL AS MID LEVEL COLD POOL MOVES ACROSS PARTS OF CO. ...PARTS OF NRN PLATEAU REGION... LOW PRESSURE AHEAD OF ADVANCING TROUGH WILL BE MOVING ACROSS THIS REGION. ONCE AGAIN...AIR MASS IS EXPECTED TO DESTABILIZE AND STEEPENING LAPSE RATES TO AROUND 8C/KM WOULD SUPPORT STRONG/SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND POSSIBLY HAIL. ...PARTS OF SC/E CENTRAL GA... REMNANTS OF QUASISTATIONARY BOUNDARY EXTENDS E-W ACROSS EXTREME SRN SC THROUGH CENTRAL GA. STORMS ARE DEVELOPING IN THE VICINITY OF THE FRONT AT THIS TIME WITH MLCAPES APPROACHING 1000 J/KG. ISOLATED STORMS EXPECTED THROUGH EARLY TONIGHT POSSIBLY PRODUCING DAMAGING WINDS. ..MCCARTHY.. 05/22/2006  From swody1 at goshenarc.org Tue May 23 01:04:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 21:04:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230101 SWODY1 SPC AC 230059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT MON MAY 22 2006 VALID 230100Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS HIGH PLAINS FROM SERN MT TO NERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE INTERIOR NORTHWEST... ...HIGH PLAINS FROM SERN MT TO NERN NM... STRONG NEGATIVELY TILTED SHORT WAVE TROUGH...NOW LOCATED OVER THE FOUR CORNERS REGION...WILL CONTINUE TO TRACK NEWD REACHING THE CENTRAL/NRN HIGH PLAINS FROM ERN CO TO ERN WY/SERN MT BY 12Z TUESDAY. ASCENT SPREADING NEWD AHEAD OF THIS TROUGH WILL CONTINUE TO PROMOTE THUNDERSTORM DEVELOPMENT THROUGH THE REMAINDER OF THE FORECAST PERIOD FROM NERN NM/CO/SRN WY AND NNEWD INTO REST OF WY/WRN NEB/WRN DAKOTAS/ERN MT. DESPITE SOME WEAKENING OF INSTABILITY...INCREASING EFFECTIVE DEEP LAYER SHEAR DUE TO 50-60 KT SWLY MID LEVEL JET MOVING INTO CO/WRN NEB AND STRENGTHENING SLY LLJ TO 40-50 KT ALONG WRN PLAINS WILL SUPPORT STORM ORGANIZATION/ ADDITIONAL SEVERE THREAT. LARGE HAIL AND STRONG WIND GUSTS/DAMAGING WINDS SHOULD REMAIN THE PRIMARY THREATS THIS EVENING/TONIGHT. ...INTERIOR NW... EARLY EVENING WATER VAPOR IMAGERY SHOWED A SHORT WAVE TROUGH EXTENDING FROM NRN CA/NWRN NV TO OFFSHORE OF ORE. THIS IMPULSE IS PROGGED TO CONTINUE ROTATING NE THEN MORE NWD AROUND THE ERN PERIPHERY OF A LARGE DEEP UPPER LOW CENTERED 650 MILES WEST OF THE ORE/WA COAST LINE. ASCENT AHEAD OF THIS TROUGH WILL CONTINUE TO AID IN ADDITIONAL THUNDERSTORM DEVELOPMENT ACROSS MUCH OF THE INTERIOR NW. STRONG DEEP LAYER SLY SHEAR PROFILES PER 00Z SOUNDINGS COMBINED WITH MARGINAL INSTABILITY WILL MAINTAIN A SEVERE THREAT WITH BOTH BOWING SEGMENTS AND SUPERCELLS THROUGH THE EVENING. A DECREASING TREND IN THE SEVERE POTENTIAL IS EXPECTED LATER TONIGHT AS THE AIR MASS STABILIZES THROUGH DIABATIC COOLING AND IS CONVECTIVELY OVERTURNED BY ONGOING ACTIVITY. ...ERN KS/SWRN MO/NWRN AR... WEAK MCV LOCATED OVER SERN KS/SWRN MO IS EXPECTED TO MOVE VERY LITTLE OVERNIGHT AS IT REMAINS WITHIN THE AXIS OF THE UPPER RIDGE. WEAK ASCENT ALONG ERN-NRN PERIPHERIES OF THIS FEATURE ACROSS NWRN AR/SWRN MO AND EAST CENTRAL KS MAY SUPPORT A FEW ADDITIONAL STRONG/ POTENTIALLY PULSE SEVERE STORMS. HOWEVER...BOUNDARY LAYER COOLING IS EXPECTED TO LIMIT THE OVERALL SEVERE THREAT. THUS...HAVE REDUCED SEVERE PROBABILITIES ACROSS THIS REGION. ...NRN PARTS OF MS/AL TO SRN SC... AIR MASS WILL CONTINUE TO STABILIZE THIS EVENING ACROSS THIS REGION LIMITING ANY ADDITIONAL THREAT OF THUNDERSTORMS AND ATTENDANT SEVERE THREAT. ..PETERS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 06:02:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 02:02:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230559 SWODY1 SPC AC 230557 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1257 AM CDT TUE MAY 23 2006 VALID 231200Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF CENTRAL/NRN PLAINS EWD TO SRN MN/CENTRAL IA/NWRN MO... ...SYNOPSIS... STRONG NEGATIVELY TILTED MID/UPPER LEVEL SHORT WAVE TROUGH WILL TRACK NEWD ACROSS THE NRN HIGH PLAINS TODAY...THEN TURN EWD ACROSS SD/NEB TONIGHT. BAND OF 45-55 KT MID LEVEL FLOW WITHIN THE SRN-ERN PERIPHERY OF THIS TROUGH WILL SPREAD ACROSS MUCH OF THE CENTRAL/NRN PLAINS TODAY REACHING THE MID MO RIVER VALLEY TONIGHT. IN THE LOW LEVELS...A REMNANT SURFACE BOUNDARY/MOISTURE AXIS EXTENDED FROM THE GULF COAST STATES/LOWER MS VALLEY NWWD ACROSS THE OZARKS TO ERN KS/NEB TO WRN SD. NRN EXTENT OF THIS BOUNDARY WILL DEVELOP NEWD AS A PACIFIC COLD FRONT SPREADS ENEWD ACROSS SD/NEB/KS. PRIMARY SURFACE LOW IS PROGGED TO TRACK NEWD FROM ERN MT INTO SRN CANADA... WHILE A SECONDARY LOW DEVELOPS OVER CENTRAL/ERN SD AND/OR EXTENDS INTO ERN NEB BY MID-LATE AFTERNOON. IN THE WEST...ANOTHER SHORT WAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF THE DEEP LOW OVER THE NERN PACIFIC IS EXPECTED TO MOVE INLAND ACROSS THE PACIFIC NW TODAY. ...PARTS OF CENTRAL/NRN PLAINS TO SRN MN/CENTRAL IA/NWRN MO... THUNDERSTORMS...SOME POTENTIALLY SEVERE...ARE EXPECTED TO BE ONGOING AT 12Z THIS MORNING ACROSS WRN PARTS OF THE CENTRAL PLAINS TO SWRN SD WITHIN DEEP LAYER ASCENT ALONG NOSE OF STRONG NOCTURNAL SLY LLJ OVER THE WRN PLAINS AND WITH HEIGHT FALLS AHEAD OF APPROACHING TROUGH. THIS ACTIVITY IS EXPECTED TO SPREAD NEWD TOWARD THE CENTRAL DAKOTAS...BUT SHOULD WEAKEN AS THE LLJ DECREASES IN STRENGTH THIS MORNING. SLY L0W LEVEL FLOW WILL PERSIST ACROSS THE CENTRAL U.S. WITH LOWER- MID 60S SURFACE DEWPOINTS RETURNING NWD ACROSS THE ERN PLAINS AND LOWER MO RIVER VALLEY TO WRN MN. STEEP LAPSE RATES ATOP THIS MOISTURE RETURN COUPLED WITH STRONG SURFACE HEATING WILL CONTRIBUTE TO MODERATE INSTABILITY WITHIN THE WARM SECTOR BY THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP INITIALLY ACROSS CENTRAL SD IN THE VICINITY OF THE SURFACE LOW BY MID AFTERNOON... AND THEN SWD ALONG A DRY LINE INTO CENTRAL NEB....WITH MORE ISOLATED DEVELOPMENT POSSIBLE SWD INTO CENTRAL KS. MODERATE INSTABILITY COMBINED WITH INCREASING SLY LLJ ACROSS THE ERN PLAINS BENEATH STRENGTHENING SWLY MID LEVEL FLOW WILL RESULT IN FAVORABLE DEEP LAYER AND DIRECTIONAL SHEAR FOR SUPERCELLS. LARGE HAIL... SOME POSSIBLY VERY LARGE...AND DAMAGING WINDS WILL BE LIKELY. IN ADDITION...LOW-LEVEL DIRECTIONAL SHEAR/CURVED HODOGRAPHS SUGGEST POTENTIAL FOR ISOLATED TORNADOES WITH INITIAL ACTIVITY AND AS STORMS DEVELOP EWD ACROSS SD/NEB/NRN KS TOWARD WRN IA. SLY LLJ IS EXPECTED TO STRENGTHEN THIS EVENING AND VEER OVERNIGHT FROM THE ERN PLAINS INTO NRN MO TO UPPER MS VALLEY AS 60-90 METER HEIGHT FALLS DEVELOP EWD ACROSS SD INTO NRN IA/MN WITH THE APPROACH OF THE UPPER TROUGH. THIS SUGGESTS UPSCALE GROWTH OF INITIAL ACTIVITY INTO CLUSTERS OF STORMS...THEN A FORWARD PROPAGATING MCS MOVING EWD TOWARD SWRN MN/WRN IA THIS EVENING...POTENTIALLY TURNING SEWD ACROSS IA/NRN MO AND ERN KS TONIGHT. DAMAGING WINDS SHOULD BECOME PRIMARY SEVERE THREAT WITH THE MCS...THOUGH HAIL SHOULD REMAIN A THREAT AS WELL. ...WRN MO/NWRN AR... ISOLATED STORMS...SOME SEVERE...MAY DEVELOP ALONG THE SURFACE BOUNDARY EXTENDING SSEWD THROUGH WRN MO INTO NWRN AR AS THE AIR MASS BECOMES MODERATELY UNSTABLE THIS AFTERNOON. DEEP LAYER SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORMS...BUT MODELS SUGGEST SOMEWHAT WEAK UPPER FORCING WITHIN THE RIDGE AXIS SHOULD LIMIT COVERAGE OF SEVERE WEATHER. ...ERN MT/WRN ND... THUNDERSTORMS MAY BE ONGOING AT THE START OF DAY 1 ACROSS THE NRN HIGH PLAINS. MODELS SUGGEST THIS ACTIVITY SHOULD PERSIST THROUGH THE DAY WITHIN DEFORMATION ZONE ALONG NWRN PERIPHERY OF UPPER TROUGH. INSTABILITY WILL BE WEAK...BUT DEEP LAYER SHEAR MAY BECOME SUFFICIENT FOR A FEW SEVERE STORMS MAINLY ACROSS ERN MT INTO WRN ND. ...MUCH OF WA/CENTRAL-ERN ORE/WRN-NRN ID... ASCENT SPREADING NEWD ACROSS THE PACIFIC NORTHWEST TODAY AHEAD OF THE APPROACHING PACIFIC SHORT WAVE TROUGH IS EXPECTED TO PROVE SUFFICIENT IN SUPPORTING THUNDERSTORMS MOVING/DEVELOPING FROM SW-NE ACROSS THIS REGION TODAY INTO THIS EVENING. ALTHOUGH INSTABILITY IS EXPECTED TO BE MARGINAL...SURFACE HEATING COMBINED WITH STEEPENING LAPSE RATES AND STRONG DEEP LAYER SHEAR SHOULD SUPPORT A FEW SEVERE STORMS...ESPECIALLY ALONG/E OF THE WA/ORE CASCADES. ..PETERS/GRAMS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 12:53:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 08:53:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231250 SWODY1 SPC AC 231248 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 AM CDT TUE MAY 23 2006 VALID 231300Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CNTRL AND NRN PLNS... ...SYNOPSIS... NEG TILT TROUGH NOW EJECTING NE ACROSS THE CNTRL RCKYS SHOULD TURN MORE ELY AND EVOLVE INTO A CLOSED LOW AS IT MOVES OFF THE HIGHER TERRAIN LATER TODAY/TONIGHT. THE LOW SHOULD REACH NE SD BY 12Z WEDNESDAY AS DEEP LOW PERSISTS OFF THE BC CST. AT LWR LEVELS... SURFACE LOW NOW OVER SE MT SHOULD CONTINUE NE INTO CANADA AND WEAKEN AS A NEW CIRCULATION CENTER DEVELOPS CLOSER TO TRACK OF UPR LOW IN NRN SD. TRAILING COLD FRONT/LEE TROUGH ATTENDING THE LOW SHOULD BECOME BETTER DEFINED ACROSS THE CNTRL PLNS DURING THE DAY TODAY AS EFFECTS OF OVERNIGHT MCS DIMINISH. WARM FRONT SHOULD ALSO BECOME BETTER DEFINED...EXTENDING S/SE FROM THE LOW INTO LWR MO AND LWR TN VLYS. ...CNTRL/NRN PLNS... FOCUS FOR ANOTHER FAIRLY ACTIVE SEVERE WEATHER DAY WILL SHIFT E/NE INTO THE CNTRL/NRN PLNS...WHERE ASCENT AND SHEAR WILL BE MAXIMIZED AHEAD OF CNTRL RCKYS/HI PLNS TROUGH. SURFACE HEATING AND MID LEVEL COLD ADVECTION WILL FOSTER SUBSTANTIAL DESTABILIZATION AHEAD OF MERGING PACIFIC COLD FRONT/LEE TROUGH FROM SD SWD INTO KS. SBCAPE SHOULD RANGE FROM 1000 TO 2000 J/KG FROM SD SWD INTO NRN/ERN KS ...WITH GREATER MOISTURE AVAILABILITY/STRONGER HEATING COMPENSATING FOR WARMER MID LEVEL TEMPS/WEAKER FORCING WITH SWD EXTENT. AMPLE SHEAR WILL BE PRESENT FOR SUSTAINED STORMS/SUPERCELLS. FORCING/INSTABILITY CONSIDERATIONS SUGGEST THAT TSTMS WILL FIRST DEVELOP IN SD/NRN NEB...CLOSER TO DEVELOPING SURFACE WAVE. ACTIVITY SHOULD THEN BUILD SWD WITH TIME...LIKELY INTO KS BY EARLY EVENING. MODERATE TO STRONG /35-45 KT/ SWLY MID LEVEL JET...CHARACTER OF FORCING AND LIKELIHOOD FOR DEEP MIXING SUGGEST THAT STORMS IN NEB SHOULD TEND TO BE OUTFLOW-DOMINANT...WITH FAIRLY RAPID EVOLUTION INTO FORWARD-PROPAGATING LINES/BANDS WITH HIGH WIND. CELLS ON THE SRN FRINGE OF THIS ACTIVITY COULD ALSO POSE A THREAT FOR LARGE HAIL AND POSSIBLY A TORNADO OR TWO INTO NRN KS. THE STORMS SHOULD EVOLVE INTO AN MCS THAT EVENTUALLY TURNS MORE ESE TOWARD MO/WRN AND SRN IA TONIGHT. IN SD AND NRN ND...CLOUDS AND PROXIMITY OF DEVELOPING SURFACE LOW SHOULD KEEP BOUNDARY LAYER MIXING MORE LIMITED. WHILE DEEP SHEAR WILL BE WEAKER RELATIVE TO POINTS FARTHER S...BACKED NEAR-SURFACE FLOW WILL CONTRIBUTE TO ENHANCED LOW LEVEL SHEAR. STORMS IN THIS CORRIDOR MAY THEREFORE POSE A THREAT FOR TORNADOES IN ADDITION TO HAIL AND LOCALLY DAMAGING WIND. FARTHER N/NW...LOW LEVEL CONVERGENCE INVOF DEFORMATION ZONE NW OF EJECTING TROUGH...COUPLED WITH DAYTIME HEATING...MAY YIELD A FEW SMALL CLUSTERS OF STORMS WITH MARGINALLY SEVERE HAIL/WIND IN ERN MT/WRN ND. IN ADDITION...WIDELY SCATTERED ELEVATED STORMS... A FEW POSSIBLY WITH HAIL...MAY PERSIST/DEVELOP IN WARM ADVECTION ZONE OVER ERN ND/NRN MN. ...PAC NW INTO NRN ID... LARGE SCALE ASCENT WILL INCREASE OVER PARTS OF WA/ORE AND ID LATER TODAY AS SHORTWAVE IMPULSE NOW APPROACHING THE NRN CA CST SWEEPS NEWD. WHILE INSTABILITY WILL REMAIN LIMITED AND LOW LEVEL CONVERGENCE WEAK...DIFFERENTIAL HEATING AND LARGE SCALE FORCING MAY PROVE SUFFICIENT FOR SCATTERED LATE DAY/EVENING STORMS. SHEAR PROFILES AND COOL AIR ALOFT COULD YIELD A FEW SEVERE CELLS... ESPECIALLY ALONG/E OF THE WA/ORE CASCADES. ..CORFIDI/MEAD/GRAMS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 16:27:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 12:27:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231622 SWODY1 SPC AC 231620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT TUE MAY 23 2006 VALID 231630Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF THE NRN AND CENTRAL PLAINS... ...NRN/CENTRAL PLAINS... COMPACT MID/UPPER LEVEL SYSTEM WITH ASSOCIATED 45+ KT SSWLY MID LEVEL JET WILL SPREAD EWD ACROSS THE CENTRAL AND NRN PLAINS TODAY. SYSTEM WILL OVERSPREAD A MODEST LATE-MAY BOUNDARY LAYER WITH CURRENT SURFACE DEW POINTS IN THE LOWER-MID 60S AS FAR NORTH AS SERN SD THIS MORNING. STRONG HEATING WILL BE COMMON TODAY AHEAD OF ADVANCING SURFACE COLD FRONT/TROUGH MOVING W-E ACROSS THE PLAINS AND SUPPORT TEMPERATURES APPROACHING 90F INTO NEB/SD. HEATING AND MID LEVEL DRY INTRUSION WILL SUPPORT STRONG MIXING/DRYING ALONG WRN EDGE OF LOW LEVEL MOIST AXIS...THOUGH MORNING UA ANALYSES/SOUNDINGS INDICATE BOUNDARY LAYER MOISTURE REMAINS SUFFICIENTLY DEEP FOR 60-65F SURFACE DEW POINTS TO SURVIVE DEEP MIXING ACROSS ERN KS INTO SERN SD. THIS WILL SUPPORT A MODERATE TO STRONGLY UNSTABLE AIR MASS BY THE LATE AFTERNOON...WITH RAPID SEVERE THUNDERSTORM DEVELOPMENT LIKELY AROUND 20-21Z ALONG SURFACE TROUGH FROM CENTRAL SD INTO NEB/FAR NRN KS. SHEAR WILL BECOME INCREASINGLY FAVORABLE FOR SUPERCELLS...AND POSSIBLY A FEW TORNADOES...AS REGION IS PLACED UNDER 35-40 KT SLY LLJ. LARGE SURFACE T/TD SPREADS SHOULD RESULT IN RELATIVELY HIGH CLOUD BASES/LCLS AND MAY INHIBIT PERSISTENT TORNADO THREAT WITH DEVELOPING SUPERCELLS. LARGE HAIL AND DAMAGING WINDS WILL BE PREVAILING SEVERE THREAT AS STORMS CONSOLIDATE INTO ONE OR MORE SQUALL LINES/CLUSTERS AND SHIFT ENEWD THROUGH THE EVENING. MORE ORGANIZED CLUSTERS/MCSS WILL LIKELY TURN MORE ESEWD AFTER DARK AND SPREAD ISOLATED SEVERE THREAT INTO MORE OF WRN IA/MO AND SRN/ERN KS. STRONG ASCENT/CONVERGENCE WILL ALSO SUPPORT THUNDERSTORM DEVELOPMENT NEAR LOW CENTER/OCCLUDED FRONT OVER WRN HALF OF ND INTO FAR NERN MT PRIOR TO 21Z. MLCAPE AND DEEP LAYER SHEAR WILL BE WEAKER IN CLOSER PROXIMITY TO MID LEVEL LOW AND ALONG NWRN PORTION OF LOW LEVEL MOISTURE AXIS. HOWEVER...MLCAPE AROUND 1000 J/KG AND STRONG ASCENT WILL LIKELY SUPPORT A SEPARATE CLUSTER OF SEVERE THUNDERSTORMS INTO WRN ND/FAR NERN MT THROUGH THE EARLY EVENING. ...PAC NW EAST OF THE CASCADES... WELL DEFINED SHORTWAVE TROUGH WILL REMAIN NEGATIVELY TILTED AS IT MOVES NNEWD ACROSS ORE AND WA TODAY. CLOUDS AHEAD OF THIS FEATURE MAY LIMIT HEATING/OVERALL INSTABILITY ACROSS CENTRAL/ERN ORE/WA. HOWEVER...SUFFICIENT HEATING WILL OCCUR FOR MODEST INSTABILITY AND A GENERAL INCREASE IN DEEP MOIST CONVECTION SPREADING NWD THROUGH THE AFTERNOON AHEAD OF APPROACHING SYSTEM. OVERALL SETUP APPEARS MARGINAL FOR SUSTAINED SEVERE THREAT...THOUGH AN ISOLATED SEVERE THUNDERSTORM OR TWO IS STILL POSSIBLE. ..EVANS/CROSBIE.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 19:54:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 15:54:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231951 SWODY1 SPC AC 231949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT TUE MAY 23 2006 VALID 232000Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT ACROSS PARTS OF THE NRN AND CENTRAL PLAINS.... ...SYNOPSIS... WATER VAPOR IMAGERY SHOWS THE MID/UPPER LEVEL LOW IS NOW OVER NWRN SD/SWRN ND/SERN MT. THE LOW IS EXPECTED TO BEGIN MOVING EWD ALONG THE ND/SD BORDER THROUGH TONIGHT. LATEST SURFACE ANALYSIS SHOWS 997 LOW OVER THE MT/ND BORDER WITH A COLD FRONT THAT EXTENDS SEWD/SWD ACROSS WRN NEB AND NWRN KS INTO NERN NM. AHEAD OF THE FRONT...AIR MASS IS MOIST AND UNSTABLE WITH SURFACE DEW POINTS IN THE LOW/MID 60S AND MLCAPES BETWEEN 1000 AND 1500 J/KG. ...NRN AND CENTRAL PLAINS... AS MID/UPPER LEVEL LOW BEGINS MOVING EWD WITHIN THE NEXT FEW HOURS...LATEST RUC MODEL INDICATES AN INCREASE OF LOW LEVEL FLOW TO 40 KTS FROM NWRN OK NWD INTO SERN SD. ALSO...MID LEVEL FLOW WILL BECOME MORE WLY AT AROUND 50 KTS ENHANCING DEEP LAYER SHEAR PROFILES ACROSS ERN NEB INTO SERN SD. THIS IS REFLECTED IN THE LATEST FORECAST SOUNDINGS ACROSS THE AREA WHERE SHEAR BECOMES FAVORABLE FOR SUPERCELL STORMS. THIS ALSO COINCIDES WITH STRONG FRONTAL PUSH EWD ENHANCING UVVS ALONG THE WRN PARTS OF THE MOIST AXIS. AIR MASS IS EXPECTED TO DESTABILIZE AS ASSOCIATED MID LEVEL COLD POOL MOVES EWD OVER AREA WITH MLCAPES FORECAST TO 2000 J/KG. THUS...LARGE HAIL IS EXPECTED ALONG WITH THE POSSIBILITY OF SOME TORNADOES THIS AFTERNOON AND EARLY TONIGHT. COLD FRONT IS EXPECTED TO EXTEND SEWD/SWD THROUGH N CENTRAL SD/ERN NEB INTO CENTRAL KS BY MID EVENING WITH A LINE OF STRONG/SEVERE THUNDERSTORMS JUST AHEAD OF IT. LOW LEVEL JET IS PROJECTED TO INCREASE TO 50 KT ALONG THE NEB/IA BORDER. MODELS SHOW THAT DEEP LAYER SHEAR DECREASES FROM 40-50 KT TO 30-40 KT OVERNIGHT. THUS... MCS IS EXPECTED TO TAKE OVER TONIGHT ACROSS ERN NEB/WRN IA INTO NWRN MO WITH MAIN THREATS BEING HAIL AND DAMAGING WINDS. ..MCCARTHY.. 05/23/2006  From swody1 at goshenarc.org Wed May 24 01:02:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 21:02:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240059 SWODY1 SPC AC 240057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT TUE MAY 23 2006 VALID 240100Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF NRN/CENTRAL PLAINS EWD INTO WRN MN/WRN-CENTRAL IA AND NWRN MO... ...NRN/CENTRAL PLAINS INTO NWRN MO/WRN-CENTRAL IA/SWRN MN... UPPER TROUGH...CURRENTLY LOCATED OVER THE WRN DAKOTAS...WILL BEGIN TO MAKE A MORE EWD MOVEMENT ACROSS ND/SD THE REST OF THIS FORECAST PERIOD. BAND OF 50 KT SWLY MID LEVEL WINDS ACCOMPANYING THIS STORM SYSTEM AND NOW EXTENDING FROM WRN KS ACROSS NEB TO ERN SD WILL CONTINUE TO TRANSLATE EWD ATOP SOMEWHAT NARROW/MOIST WARM SECTOR OVER THE ERN PLAINS TO WRN MN/WRN IA/WRN MO. THIS MID LEVEL FLOW COMBINED WITH STRENGTHENING NOCTURNAL SLY LLJ TO 50 KT FROM ERN KS TO ERN NEB/WRN IA WILL RESULT IN INCREASING DEEP LAYER SHEAR FOR CONTINUATION OF ORGANIZED STORMS ALONG COLD FRONT ADVANCING EWD THROUGH SD/NEB/KS OVERNIGHT. SHEAR VECTORS ORIENTED PARALLEL TO MUCH OF THE ONGOING LINE OF STORMS FROM ERN SD SWD INTO ERN NEB EXPECTED TO MAINTAIN LINEAR CONVECTIVE MODE WITH DAMAGING WINDS AND HAIL THE PRIMARY THREATS...THOUGH EMBEDDED SUPERCELLS WILL BE POSSIBLE. TORNADO POTENTIAL...EXPECTED MAINLY DURING THIS EVENING...SHOULD EXTEND FROM PARTS OF ERN NEB INTO WRN IA AND SWD INTO NERN KS WHERE LOW LEVEL DIRECTIONAL SHEAR WILL BE GREATEST ALONG INCREASING LLJ AND BENEATH SWLY FLOW ALOFT. ALSO...DEEP LAYER SHEAR INCREASING IN MAGNITUDE IS EXPECTED TO REMAIN MORE NORMAL TO THE COLD FRONT/PRE-FRONTAL DRY LINE FAVORING ADDITIONAL THREAT FOR DISCRETE STORMS. LLJ WILL BE MAINTAINED AND SHOULD VEER TO SWLY OVERNIGHT IN RESPONSE TO 60-90 METER 500 MB HEIGHT FALLS SPREADING EWD TOWARD THE UPPER MS VALLEY AHEAD OF THE UPPER TROUGH. PRIND SUGGEST UPSCALE GROWTH OF ONGOING ACTIVITY INTO AN MCS WITH STRONG WIND GUSTS AND HAIL BECOMING THE PRIMARY THREAT...WITH ACTIVITY POTENTIALLY TURNING TOWARD THE SE ACROSS IA INTO NRN MO/ERN KS. ...NWRN MN WWD THROUGH ND TO NERN MT... AIR MASS IS MODERATELY UNSTABLE ACROSS NWRN MN WWD THROUGH NRN ND INTO NERN MT. ASCENT AHEAD OF THE UPPER TROUGH IS EXPECTED TO SUPPORT ADDITIONAL THUNDERSTORMS THROUGH THE EVENING/OVERNIGHT ACROSS MAINLY ND INTO NWRN MN...WITH A DECREASING TREND OVER ERN MT. ONGOING STORMS OVER PARTS OF WEST CENTRAL MN/SERN ND AND MORE RECENT STORMS WWD ALONG VICINITY OF ND/SD BORDER WILL CONTINUE TO TRACK NNEWD INTO THE INSTABILITY AXIS SUPPORTING SOME THREAT FOR HAIL AND STRONG WIND GUSTS. ...NERN ORE/ERN WA/NRN ID... ASCENT AHEAD OF A SHORT WAVE TROUGH MOVING NNEWD ACROSS ORE/WA AT THIS TIME WILL AID IN ADDITIONAL THUNDERSTORM DEVELOPMENT THIS EVENING. STEEP LAPSE RATES...MARGINAL INSTABILITY AND 25-30 KT OF DEEP LAYER SHEAR PER 00Z RAOB AT SPOKANE SUGGESTS A CONTINUED POTENTIAL FOR AN ISOLATED SEVERE THREAT OF HAIL/STRONG WIND GUSTS. ..PETERS.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 05:58:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 01:58:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240556 SWODY1 SPC AC 240554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT WED MAY 24 2006 VALID 241200Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN IA/SRN WI/IL SWWD TO CENTRAL OK... ...SYNOPSIS... UPPER TROUGH TOPPING THE MEAN RIDGE DURING THE FIRST FEW HOURS OF THE DAY 1 FORECAST PERIOD ACROSS THE ERN DAKOTAS IS EXPECTED TO THEN TRACK SEWD OVER THE UPPER MS VALLEY/WRN GREAT LAKES REGION TODAY. PRIMARY SURFACE LOW IS PROGGED TO TRACK EWD FROM ND INTO NRN/CENTRAL MN BY THIS AFTERNOON. AT 12Z TODAY...AN OCCLUDED FRONT SHOULD EXTEND SEWD INTO WRN IA...THEN SWWD AS A COLD FRONT THROUGH ERN KS TO NWRN OK. THESE BOUNDARIES WILL MOVE EWD EXTENDING FROM THE UPPER MS VALLEY THROUGH ERN IA TO NRN MO AND THEN SWWD INTO CENTRAL OK BY 25/00Z. MEANWHILE...A QUASISTATIONARY FRONT WILL PERSIST FROM THE GULF COAST STATES NNWWD INTO THE MID MS VALLEY WHERE IT WILL INTERSECT THE COLD FRONT. ...ERN IA/SRN WI/IL SWWD THROUGH MO TO CENTRAL OK... THUNDERSTORMS SHOULD BE ONGOING AT THE START OF THE FORECAST PERIOD ACROSS PARTS OF IA/NRN MO WITHIN WAA REGIME ALONG NOSE OF SWLY LLJ. THIS ACTIVITY SHOULD SPREAD EWD INTO SRN WI/IL AND TEND TO DIMINISH IN INTENSITY AS THE LLJ WEAKENS. HOWEVER...IF STORMS PERSIST INTO THE LATE MORNING/AFTERNOON...IT IS POSSIBLE FOR THIS ACTIVITY TO INGEST INCREASINGLY HIGHER THETA-E AIR FROM THE DESTABILIZING WARM SECTOR AND INTENSIFY. SSWLY LOW LEVEL FLOW EXPECTED IN ADVANCE OF THE SURFACE FRONTS WILL ADVECT SURFACE DEWPOINTS IN THE MID 60S...NOW RESIDING ACROSS SERN PLAINS/OZARKS TO WRN IA...NEWD INTO IL/WI. SURFACE HEATING MAY BE LIMITED ACROSS PARTS OF IL/IND DUE TO ANY ONGOING THUNDERSTORMS/ ATTENDANT CLOUDINESS SPREADING ESE THROUGH THESE STATES INTO THE AFTERNOON. STRONGER SURFACE HEATING WILL BE MORE LIKELY IN THE WAKE OF THIS MORNING ACTIVITY FROM ALONG/E OF THE COLD FRONT IN CENTRAL OK/SERN KS THROUGH MO TO SWRN WI...WHERE SURFACE DEWPOINTS IN THE MIDDLE 60S WILL RESULT IN MODERATE INSTABILITY /MLCAPE UP TO 2500 J/KG/. BAND OF 40-55 KT WNWLY MID LEVEL FLOW ACCOMPANYING UPPER TROUGH WILL SPREAD ESE ACROSS THE COLD FRONT AND WARM SECTOR THIS AFTERNOON RESULTING IN 35-45 KT OF DEEP LAYER SHEAR. THUNDERSTORMS SHOULD DEVELOP ALONG THE ADVANCING FRONTS FROM WRN WI SSWWD THROUGH ERN IA BY MID-LATE AFTERNOON...WITH POTENTIAL FOR DEVELOPMENT ALSO ALONG ANY CONVECTIVE BOUNDARIES LEFT OVER BY MORNING CONVECTION IN IL/MO. MODERATE INSTABILITY COMBINED WITH INCREASING DEEP LAYER SHEAR SUPPORTS POTENTIAL FOR SUPERCELLS WITH MODELS SUGGESTING POTENTIAL FOR LINEAR STRUCTURE/SQUALL LINE DEVELOPMENT ALONG THE COLD FRONT...ESPECIALLY OVER WI INTO IL. AS ASCENT AHEAD OF THE UPPER TROUGH CONTINUES TO SPREAD SE... THUNDERSTORMS SHOULD CONTINUE TO DEVELOP SWWD ALONG THE COLD FRONT INTO NERN OK...AND EVENTUALLY CENTRAL OK AS THE SWLY LLJ STRENGTHENS. POTENTIAL EXISTS FOR STORMS TO CONTINUE THROUGH THE NIGHT SPREADING EWD INTO THE OH VALLEY AND SWD THROUGH THE OZARKS AND OK. SEVERE THREAT INTO OH VALLEY SHOULD BE MITIGATED BY EWD EXTENT OF AIR MASS DESTABILIZATION. ...ERN DAKOTAS/MUCH OF MN... THUNDERSTORMS WILL BE POSSIBLE FARTHER N ALONG THE TRACK OF THE SURFACE LOW AND ASSOCIATED WITH COLDER MID LEVEL TEMPERATURES WITH THE UPPER TROUGH. WEAK INSTABILITY/SHEAR SHOULD PRECLUDE DEVELOPMENT OF SEVERE WEATHER WITH THIS ACTIVITY. ..PETERS/JEWELL.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 12:55:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 08:55:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241252 SWODY1 SPC AC 241251 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 AM CDT WED MAY 24 2006 VALID 241300Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS ... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VLY SW INTO ERN PARTS OF THE SRN PLNS... ...SYNOPSIS... NE SD UPR LOW SHOULD CONTINUE GENERALLY E ACROSS THE UPR MS VLY THIS PERIOD AS DEEP E PACIFIC LOW EDGES SLOWLY TOWARD THE WA CST. THE SD LOW SHOULD...HOWEVER...TURN SLIGHTLY S OF E WITH TIME AS /1/ SYSTEM HAS PASSED HI PLNS RIDGE AXIS AND /2/ WNWLY JET STREAK NOW OVER THE NEB PANHANDLE WILL DRIVE STRONGEST FORCING FOR ASCENT/UPR DIVERGENCE ESEWD. AT LWR LEVELS...PACIFIC OCCLUSION/COLD FRONT ARCING S AND SW FROM DAKS/MN SURFACE LOW SHOULD PROGRESS STEADILY SE INTO THE MID MS VLY TODAY/TONIGHT. EXPECT THAT THE SRN PART OF THIS BOUNDARY WILL EDGE ONLY SLOWLY S/SE ACROSS WRN MO/KS...AND LIKELY WILL DEVOLVE INTO A WINDSHIFT LINE AS A NEW THERMAL SURGE DEVELOPS FARTHER N IN RESPONSE TO NEB JET STREAK. ELSEWHERE...WEAK N/S WARM FRONT NOW IN CNTRL/ERN MO SHOULD MOVE E/NE THROUGH THE PERIOD...REACHING CNTRL OH BY 12Z THURSDAY. ...ERN IA/SW WI/NW IL... CONVECTIVE DEBRIS ASSOCIATED WITH LAST EVENING'S SQUALL LINE SHOULD CLEAR FROM SW TO NE ACROSS WRN WI/EXTREME SE MN/ERN IA AND NW IL LATER THIS MORNING. GIVEN CURRENT LOW LEVEL MOISTURE DISTRIBUTION...AND 30-40 KT SWLY LLJ ACROSS WRN MO/IA...SETUP SHOULD ALLOW FOR CONSIDERABLE LOW LEVEL DESTABILIZATION /SBCAPE TO 2000 J PER KG/ NEWD INTO MDT RISK AREA ALONG/AHEAD OF COLD/OCCLUDED FRONT. CONVERGENCE ALONG FRONT...AND LARGE SCALE ASCENT IN EXIT REGION OF 50+ KT MID LEVEL JET STREAK...SHOULD CREATE FAVORABLE ENVIRONMENT FOR STORM INITIATION BY MID AFTERNOON OVER WRN WI. ACTIVITY SHOULD THEN DEVELOP S ALONG FRONT INTO ERN IA/NW IL. LINEAR FORCING...MODERATE TO STRONG MEAN FLOW AND DRY AIR AT MID LEVELS SUGGEST THAT STORMS WILL...SIMILAR TO THOSE IN CNTRL NEB YESTERDAY...FAIRLY QUICKLY EVOLVE INTO A FORWARD-PROPAGATING LINE PRODUCING A CORRIDOR OF HIGH WIND/HAIL. BEFORE MERGING... INDIVIDUAL STORMS MAY ALSO POSE A THREAT FOR TORNADOES GIVEN EXPECTED DEGREE OF LOW LEVEL DIRECTIONAL SHEAR AND MOISTURE /AVERAGE DEWPOINTS IN THE LOW 60S/. THE SQUALL LINE SHOULD CONTINUE E INTO THE REMAINDER OF WI AND NRN IL EARLY TONIGHT. THE STORMS SHOULD DIMINISH FAIRLY RAPIDLY GIVEN WEAKER DESTABILIZATION EXPECTED IN THESE AREAS. ...CNTRL/SRN IL WSW INTO CNTRL/SRN MO AND PARTS OF AR/OK... SURFACE HEATING AND CONVERGENCE ALONG WEAKENING FRONT/WINDSHIFT LINE SHOULD RESULT IN A SEPARATE AREA OF MORE CONCENTRATED STORMS OVER PARTS OF MO THIS AFTERNOON/EVENING...ALONG ROUGHLY THE I-70 AND I-44 CORRIDORS FROM NEAR STL TO COU/SGF. SUBSTANTIAL SBCAPE /UP TO 3000 J PER KG/ SHOULD BE PRESENT IN THIS REGION BENEATH 35-40 KT WLY MID LEVEL FLOW ON SRN FRINGE OF NEB JET. HIGH LEVEL WINDS...HOWEVER...ARE FORECAST TO REMAIN RELATIVELY WEAK /AOB 30 KTS/ AND ORIENTED ROUGHLY PARALLEL TO INITIATING BOUNDARY. STORMS/POTENTIAL SUPERCELLS WILL POSE A THREAT FOR LARGE HAIL/HIGH WIND AND PERHAPS AN ISOLATED TORNADO DURING THEIR EARLY STAGES OF DEVELOPMENT. BUT THE ACTIVITY SHOULD FAIRLY QUICKLY EVOLVE INTO ONE OR MORE ELONGATED CLUSTERS THAT...WHILE CONTAINING REMNANT EMBEDDED CIRCULATIONS...SHOULD POSE A DIMINISHING THREAT FOR HIGH-END SEVERE. THE CLUSTERS COULD EXHIBIT BOTH BACKBUILDING/ REGENERATIVE TENDENCIES SWWD INTO AR/OK...AND FORWARD PROPAGATING SEGMENTS EWD INTO IL/IND LATER TONIGHT THROUGH EARLY THURSDAY. ..CORFIDI/JEWELL.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 16:26:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 12:26:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241616 SWODY1 SPC AC 241614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT WED MAY 24 2006 VALID 241630Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF SWRN WI AND FAR ERN IA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN MS RIVER VALLEY/WRN GREAT LAKES INTO THE OZARKS... ...SYNOPSIS... COMPACT...VERTICALLY STACKED LOW OVER THE ERN DAKOTAS WILL SHIFT SLOWLY EWD TOWARD THE NRN MS RIVER VALLEY TODAY...WITH TRAILING COLD FRONT/SURFACE TROUGH ADVANCING STEADILY ESEWD INTO WRN WI/ERN IA/NRN MO. TAIL END OF THIS BOUNDARY WILL SLOW AND LIKELY STALL INTO CENTRAL OK/SERN KS/WRN MO BY LATER TODAY. STRONG HEATING AND DEEP BOUNDARY LAYER MIXING WILL TEND TO ERODE CURRENT MID/UPPER 60F SURFACE DEW POINT AXIS NOW EXTENDING FROM ERN OK INTO ERN IA. HOWEVER...INCREASING SSWLY BOUNDARY LAYER FLOW AHEAD OF THIS SYSTEM WILL LIKELY MAINTAIN AT LEAST MID/UPPER 50F SURFACE DEW POINTS NWD ACROSS THE LOWER MO AND INTO THE NRN MS RIVER VALLEYS. ...NRN MS RIVER VALLEY ACROSS ERN IA AND INTO NWRN IL/WI... STRONGEST ASCENT ALONG NOSE OF 50+ KT MID/UPPER LEVEL JET AND JUST AHEAD OF DEEP CONVERGENCE AXIS/FAST MOVING SHORTWAVE TROUGH NOW EVIDENT ON WV IMAGERY MOVING INTO SWRN MN/ERN IA WILL OVERSPREAD THE NRN MS RIVER VALLEY TODAY. THIS IS EXPECTED TO FOCUS GREATEST POTENTIAL/COVERAGE OF SEVERE THUNDERSTORMS ALONG NRN EXTENT OF MODEST LOW LEVEL MOISTURE AXIS DURING THE MID TO LATE AFTERNOON. INITIATION MAY OCCUR INTO FAR ERN MN/W-CENTRAL WI BY THE MID AFTERNOON WITH DEVELOPMENT INCREASING SSWWD INTO ERN IA/NWRN IL BY THE EARLY EVENING. MLCAPE AROUND 1000 J/KG IS ANTICIPATED INTO SWRN WI WITH CINH WEAKENING/DIMINISHING PRIOR TO 21Z. FORECAST SOUNDINGS INDICATE 35-45 KT EFFECTIVE SHEAR WILL DEVELOP ACROSS THIS REGION...WITH NEAR UNIDIRECTIONAL WIND PROFILES AND STRONG/DEEP ASCENT LIKELY SUPPORTING QUICK EVOLUTION INTO ONE OR MORE LINES OF STORMS. EMBEDDED OR PRECEEDING SUPERCELLS MAY HAVE BRIEF TORNADO POTENTIAL GIVEN MAGNITUDE OF LOW AND DEEP LAYER SHEAR. HOWEVER...SUPERCELLS WILL LIKELY BECOME OUTFLOW DOMINANT WITHIN LARGE T-TD SURFACE SPREADS/STEEP LOW LEVEL LAPSE RATES AND MAY ENHANCE BOW ECHO DEVELOPMENT WITHIN EWD MOVING LINEAR MCS. E-SEWD EXTENT OF SEVERE THREAT WILL BE LIMITED BY NARROW INSTABILITY AXIS ACROSS WI AND LOSS OF HEATING THIS EVENING. ...MO ESEWD INTO LOWER OH RIVER VALLEY AND SWWD INTO SERN KS/OK... WEAKER ASCENT SUGGESTS HEATING WILL DRIVE DEVELOPMENT SSWWD ALONG AND AHEAD OF APPROACHING SURFACE TROUGH THIS AFTERNOON ACROSS MO AND INTO PORTIONS OF SERN KS/NERN OK AND POSSIBLY INTO CENTRAL/SWRN OK. SHEAR DIMINISHES WITH SWWD EXTENT INTO THE SRN PLAINS AND RESULTANT STORMS WILL DEVELOP WEAKER ORGANIZATION SOUTHWEST OF THE OZARK PLATEAU. CONVECTIVE EVOLUTION A BIT MORE DIFFUSE ACROSS THIS REGION AS ALL THE MORNING MODELS INCREASE THUNDERSTORMS AHEAD OF SURFACE TROUGH ACROSS MUCH OF MO BY THE EARLY AFTERNOON. THOUGH SHEAR AND ASCENT WILL BE WEAKER SOUTH OF IA...AIR MASS WILL BECOME MODERATE TO STRONGLY UNSTABLE EARLY THIS AFTERNOON. SHOULD THIS DEVELOPMENT INCREASE AS CAP WEAKENS ACROSS THIS WARM SECTOR...30-40 KT OF EFFECTIVE SHEAR WILL SUPPORT ORGANIZATION INTO MULTICELL CLUSTERS/LINES WITH EMBEDDED SUPERCELLS. LARGE HAIL AND DAMAGING WINDS WILL ACCOMPANY THESE STORMS AS THEY INCREASE IN COVERAGE/INTENSITY AND SPREAD SLOWLY ESEWD THROUGH THE EVENING. AS CAP BREAKS SWWD INTO OK EARLY THIS EVENING...ISOLATED STORMS MAY PRODUCE DAMAGING WINDS GIVEN VERY STRONG HEATING. HOWEVER... SEVERE THREAT WILL BECOME MORE PULSE IN NATURE/ISOLATED WITH SWWD EXTENT. ...ERN ND AND VICINITY... RUC INDICATES SUFFICIENT HEATING LATER TODAY WITHIN RELATIVELY MOIST LOW LEVEL AIR MASS INTO NWRN MN/ERN ND WHERE SURFACE DEW POINTS ARE AROUND 60F. GIVEN COLD AIR ALOFT UNDER -12C MID LEVEL COLD POCKET AND EXPECTED 500-750 J/KG SBCAPE ACROSS THIS REGION... STORMS MAY PRODUCE HAIL AND WILL INTRODUCE LOW SEVERE PROBABILITIES INTO THE EARLY EVENING. ..EVANS/CROSBIE.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 20:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 16:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 242002 SWODY1 SPC AC 242001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT WED MAY 24 2006 VALID 242000Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF SRN WI/ERN IA/NWRN IL/NERN MO... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID AND UPPER MS VALLEY INTO THE OZARKS... ...OZARKS INTO THE MID AND UPPER MO VALLEY... THUNDERSTORMS CONTINUE TO DEVELOP ACROSS WRN WI/CENTRAL AND NRN IL AND INTO PARTS OF MO AHEAD OF COLD FRONT...WHERE AIRMASS HAS BECOME MODERATELY UNSTABLE. AS UPPER LOW NOW OVER ERN ND MOVES SLOWLY SEWD...EXPECT SWLY LOW-LEVEL JET TO INCREASE BENEATH MODERATE WNWLY FLOW AT MID-LEVELS. RESULTING SHEAR WILL THUS CONTINUE TO FAVOR SEVERE STORMS/SUPERCELLS ACROSS THIS REGION. ALONG WITH THREAT FOR LARGE HAIL...DAMAGING WINDS AND A COUPLE OF TORNADOES APPEAR LIKELY AS STORM COVERAGE INCREASES. CONVECTION MAY EVOLVE INTO ONE OR MORE SEVERE MCS LATER THIS EVENING...THOUGH EWD EXTENT OF THREAT INTO INDIANA SHOULD REMAIN LIMITED DUE TO COOLER/MORE STABLE AIRMASS E OF NNW-ESE WARM FRONT NOW OVER WI/IL. ...NRN FL/FL PANHANDLE... A COUPLE OF PULSE-TYPE STORMS CAPABLE OF PRODUCING MARGINAL HAIL OR BRIEF GUSTY WINDS WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON WITHIN MOIST/MARGINALLY-UNSTABLE AIRMASS INDICATED INVOF SEA-BREEZE BOUNDARY ACROSS THE FL PANHANDLE/NRN FL. THREAT SHOULD DIMINISH RAPIDLY THIS EVENING. ..GOSS.. 05/24/2006  From swody1 at goshenarc.org Thu May 25 00:46:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 20:46:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250045 SWODY1 SPC AC 250044 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 PM CDT WED MAY 24 2006 VALID 250100Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH EARLY THURSDAY MORNING FROM SRN WI INTO IL/IN AND MO.... ...SYNOPSIS... MID/UPPER LEVEL LOW WILL CONTINUE TO DRIFT ESEWD FROM W CENTRAL MN INTO SWRN WI THE REMAINDER OF TONIGHT. OCCLUDED LOW OVER W CENTRAL MN HAS FRONTAL BOUNDARY EXTENDING SEWD INTO SWRN WI...THEN SWD AND SWWD THRU NWRN MO INTO THE OK PANHANDLE. CURRENT STRONG/SEVERE THUNDERSTORM ACTIVITY HAS LAID OUT SEVERAL CONVECTIVE BOUNDARIES ACROSS WRN LOWER MI INTO NRN INDIANA...AND ACROSS CENTRAL IL INTO CENTRAL MO. ...PARTS OF WI/IL/INDIANA/MO... MUCH OF THE INTENSE CONVECTION IS NOW MOVING SWD WITHIN THE LINE MAINLY GOING FOR THE BETTER MOISTURE/INSTABILITY SOURCE. THE ACTIVITY MOVING THROUGH NRN INDIANA TOWARDS OH IS WEAKENING AS IT PULLS FURTHER AWAY FROM STRONG DYNAMIC FORCING AND INTO MOISTURE STARVED AIR WITH OH HAVING DEW POINTS IN THE UPR 30S/LOWER 40S. THUS...PROBABILITIES FOR STRONG TO SEVERE THUNDERSTORMS WILL REMAIN ASSOCIATED WITH LINE OF ACTIVITY MOVING EWD INTO EAST CENTRAL AND SERN WI FOR THE NEXT HOUR OR SO UNTIL IT HITS LAKE BREEZE THAT EXTENDS FROM GRB SWD TO JUST W OF MKE AREA. AS STORMS WEAKEN ACROSS ERN WI...THERE COULD BE SOME DAMAGING WINDS AS STORMS COLLAPSE ALONG LAKE BREEZE BOUNDARY. FARTHER SOUTH...MAIN BAND OF STRONG/SEVERE THUNDERSTORMS EXTEND FROM S CENTRAL IL SWWD INTO S CENTRAL MO. AIR MASS HERE REMAINS VERY UNSTABLE WITH MLCAPE BETWEEN 1500 AND 2500 J/KG. COLD FRONT WILL CONTINUE TO PRESS EWD/SEWD ACROSS REGION AND STORMS COULD BUILD BACK TOWARDS THE SW THROUGH EARLY THURSDAY MORNING. SEVERAL BOW ECHOES ARE ALONG THIS LINE...THUS DAMAGING WINDS AND HAIL LOOK TO BE THE MAIN THREAT. LOOKS LIKE THE TORNADO THREAT IS DECREASING AS LINE MOVES AWAY FROM MAIN BAND OF MID LEVEL WINDS /45-55 KT/ AND THUS DECREASING SHEAR. ...PARTS OF W TX... STRONG/ISOLATED SEVERE THUNDERSTORMS HAVE DEVELOPED IN VICINITY OF SURFACE DRYLINE FROM SWRN OK INTO THE TX BIG BEND. STRONG DAYTIME HEATING HAS PUSHED MLCAPES TO AROUND 2000 J/KG...ENOUGH TO SUPPORT SOME HAIL...BUT ACTIVITY SHOULD DECREASE BY MID EVENING WITH LOSS OF DAYTIME HEATING. ..MCCARTHY.. 05/25/2006  From swody1 at goshenarc.org Fri May 26 06:40:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 02:40:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260638 SWODY1 SPC AC 260637 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0137 AM CDT FRI MAY 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NORTHEAST/MID ATLANTIC/SOUTHEAST/TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CNTRL AND NRN PLAINS/HIGH PLAINS... ...SYNOPSIS... PROGRESSIVE LARGE SCALE FLOW OF MODEST AMPLITUDE WILL CONTINUE ACROSS THE CONUS THROUGH FRIDAY AS ONE DEEP LAYER CYCLONE MOVES FROM THE GREAT LAKES TO THE NORTHEAST...AND A STRONG MID/UPPER LEVEL TROUGH EVOLVES ACROSS THE INTERIOR WEST. A MID/UPPER LEVEL RIDGE WILL SEPARATE THE TWO TROUGHS AND MOVE EAST FROM THE PLAINS TO THE MIDWEST AND DEEP SOUTH DURING THE FORECAST PERIOD. HOT AND VERY UNSTABLE CONDITIONS WILL AGAIN DEVELOP BENEATH THE RIDGE AXIS TODAY WHERE A DEEP LAYER FRONTAL ZONE WILL EXIST. EARLY TODAY...THE FRONT ORIGINATING WITH THE GREAT LAKES/NORTHEAST TROUGH...WILL EXTEND SWWD ALONG THE APPALACHIANS...THEN WWD TO THE TN VALLEY...AND NWWD INTO THE PLAINS. CONVECTIVELY ENHANCED COLD POOLS/OUTFLOW WILL LOCALLY REINFORCE THE FRONTAL ZONE FROM THE APPALACHIANS TO THE PLAINS. AS ERN TROUGH MOVES ACROSS THE NORTHEAST AND MID ATLANTIC... ASSOCIATED COLD FRONT WILL DEVELOP EAST ACROSS THE APPALACHIANS AND THEN MOVE OFF THE ATLANTIC COAST THROUGH THE PERIOD. THE BOUNDARY WILL LIKELY BECOME QUASI-STATIONARY FROM THE SRN APPALACHIANS/TN VALLEY TO THE LOWER MO VALLEY. AS WRN U.S. TROUGH SPREADS EAST AND LOW LEVEL SLY FLOW INCREASES ACROSS THE PLAINS...THE FRONTAL ZONE OVER THE PLAINS SHOULD REDEVELOP NWD FROM KS TO THE CNTRL/NRN PLAINS...AS LEE TROUGH STRENGTHENS ACROSS THE HIGH PLAINS. ...NORTHEAST/MID ATLANTIC... STRONG DYNAMIC FORCING/HEIGHT FALLS WITH THE UPPER TROUGH WILL ACT ON INCREASING INSTABILITY TO AT LEAST MAINTAIN...AND POSSIBLY ENHANCE...CONVECTIVE LINE MOVING EAST THROUGH THE AFTERNOON. STRENGTHENING DEEP LAYER FLOW COINCIDENT WITH THE INCREASING INSTABILITY SHOULD SUPPORT FAST MOVING LINE SEGMENTS WITH DAMAGING WINDS AND PERHAPS SOME HAIL FROM THE LOWER HUDSON VALLEY SWD ACROSS ERN PA AND NJ. FROM DELMARVA AREA SWD ACROSS THE VA/NC CAPES...GREATER MOISTURE AND LATER ARRIVAL OF FORCING ASSOCIATED WITH THE WITH THE UPPER TROUGH WILL ALLOW FOR GREATER DESTABILIZATION THESE AREAS. SHEAR WILL INITIALLY BE LIMITED BUT SHOULD INCREASE AS STORMS DEVELOP ON STRENGTHENING LEE TROUGH THROUGH LATE AFTERNOON. POTENTIAL FOR MORE DISCRETE CONVECTION... AT LEAST INITIALLY...AND POSSIBLE SEA/BAY/SOUND BREEZE INTERACTIONS MAY RESULT IN SLIGHTLY GREATER SUPERCELL/LARGE HAIL THREAT...IN ADDITION TO DAMAGING WINDS FROM POSSIBLE EVOLUTION INTO CONVECTIVE LINE. ...NRN/CNTRL PLAINS... INCREASINGLY STRONG SWLY FLOW ALOFT AND GRADUALLY FALLING HEIGHTS WILL STRENGTHEN LEE-TROUGHING ACROSS THE NRN AND CNTRL HIGH PLAINS TODAY. A NUMBER OF LOW AMPLITUDE DISTURBANCES ROTATING NEWD OUT OF THE LARGER SCALE WRN TROUGH ARE SUGGESTED BY MODEL GUIDANCE AND WILL AID CONVECTIVE INITIATION ACROSS THE HIGHER TERRAIN. LOW LEVEL UPSLOPE FLOW AND MOISTURE ADVECTION APPEAR TO BE GREATEST FROM NERN CO NWD ACROSS THE WRN DAKOTAS THROUGH LATE EVENING. LEE-SIDE SURFACE LOWS MAY FURTHER FOCUS CONVECTIVE DEVELOPMENT WITH ACTIVITY MOVING EWD/NEWD INTO STRONGER INSTABILITY EAST OF THE LEE TROUGH/DRYLINE. SEVERAL CLUSTERS OF STORMS/SUPERCELLS APPEAR LIKELY. LARGE HAIL AND HIGH WINDS SHOULD ACCOMPANY THIS ACTIVITY AS IT SPREADS GENERALLY NEWD THROUGH LATE EVENING WITH SOME POTENTIAL FOR ISOLATED TORNADOES NEAR ANY SURFACE LOW AND/OR LEE TROUGH/RETREATING WARM FRONT INTERSECTION. AN MCS OR TWO MAY EVOLVE THROUGH THE LATE EVENING...ESPECIALLY NEAR THE RETREATING WARM FRONT OVER NEB...AND PERHAPS ACROSS ND WHERE GUIDANCE DEPICTS STRONGER QG FORCING FOR ASCENT WILL PERSIST INTO EARLY SATURDAY. ...HIGH PLAINS SERN CO SOUTH TO BIG BEND... LEE TROUGH/DRYLINE WILL ALSO SPUR GENERALLY HIGH-BASED TSTM DEVELOPMENT FROM SERN CO SWD TO THE RIO GRANDE BY AFTERNOON. WEAKER LARGE SCALE FORCING FOR ASCENT ACROSS THESE AREAS SUGGESTS MORE ISOLATED DEVELOPMENT. NONETHELESS...VERY HOT BOUNDARY LAYER AND SUFFICIENT EFFECTIVE SHEAR WILL SUPPORT VIGOROUS SUPERCELL STORMS WITH AT LEAST A LOW PROBABILITY THREAT OF LARGE HAIL AND DAMAGING DOWNBURST WINDS. ...TN VALLEY ACROSS MID MS VALLEY AND LOWER MO VALLEY... STRONG TO EXTREME INSTABILITY WILL DEVELOP ALONG THE STALLED FRONTAL ZONE...BUT BENEATH RIDGING ALOFT AND STOUT CAPPING INVERSION. THERE IS FURTHER UNCERTAINTY REGARDING AFTERNOON TSTM DEVELOPMENT ACROSS PARTS OF THE REGION GIVEN ONGOING MCS ACTIVITY ACROSS KS AND SWRN MO. FAVORABLE ORIENTATION/FORCING FROM MCS OUTFLOWS AND RESIDUAL FRONT...COUPLED WITH LOCALLY INTENSE HEATING/DESTABILIZATION FROM TN SEWD ACROSS SC SHOULD OVERCOME CAP THESE AREAS TO RESULT IN POTENTIALLY EXPLOSIVE CONVECTIVE DEVELOPMENT. LARGE HAIL AND LOCALLY DAMAGING WINDS APPEAR POSSIBLE DURING THE DAY FROM THIS CONVECTION. HOWEVER...FROM THE MS RIVER NWWD ACROSS MO...GENERALLY WEAKER SHEAR AND FORCING BENEATH MID LEVEL RIDGE...AND CURRENT UNCERTAINTIES REGARDING MCS EVOLUTION...PRECLUDE HIGHER PROBABILITY SEVERE WEATHER FORECAST OVER THIS REGION AT THIS TIME. ...SOUTH FL... LATEST GUIDANCE INDICATED THAT DIURNAL TSTM DEVELOPMENT MAY COINCIDE WITH THE ARRIVAL OF SLIGHTLY STRONGER WLY MID LEVEL FLOW ACROSS SRN FL. STORMS DEVELOPING ON EAST COAST SEA BREEZE...AND ACROSS THE KEYS...MAY PERSIST OR BECOME BETTER ORGANIZED TO PRODUCE AN ISOLATED TORNADO...OR A COUPLE OF HAIL/WIND EVENTS. OVERALL POTENTIAL DOES NOT APPEAR TO SUPPORT HIGHER PROBABILITIES AT THIS TIME. ..CARBIN/JEWELL.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 13:09:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 09:09:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261308 SWODY1 SPC AC 261306 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 AM CDT FRI MAY 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN/CENTRAL PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC REGION INTO THE APPALACHIANS AND TN VALLEY/MID SOUTH... ...SYNOPSIS... UPPER LOW OVER THE GREAT LAKES IS FORECAST TO CONTINUE EWD TODAY ACROSS THE LOWER LAKES...OPENING INTO A TROUGH TONIGHT AS IT MOVES TOWARD THE ATLANTIC COAST. WATER VAPOR IMAGERY INDICATES THE UPSTREAM FLOW PATTERN IS BEGINNING TO AMPLIFY PER MODEL FORECASTS WITH A RIDGE BEGINNING TO BUILD OVER THE PLAINS AS TROUGH DEEPENS ALONG THE PACIFIC COAST. THESE SYSTEMS WILL PROGRESS EWD THROUGH THE PERIOD WITH THE RIDGE REACHING THE MS VALLEY WHILE THE TROUGH SETTLES OVER THE PACIFIC NORTHWEST BY 27/12Z. AT THE SURFACE...A LOW OVER LOWER MI IS EXPECTED TO MOVE EWD INTO NY THIS AFTERNOON AND ACROSS NEW ENGLAND TONIGHT. COLD FRONT TRAILING SWWD FROM THE LOW WILL MOVE ACROSS THE APPALACHIANS TOWARD THE MID ATLANTIC COAST...CONTINUING WWD AS A STATIONARY FRONT THROUGH THE TN VALLEY...THEN LIFTING NWD AS A WARM FRONT INTO THE MO RIVER VALLEY AS A LOW MOVES INTO THE NRN HIGH PLAINS TONIGHT. A SERIES OF CONVECTIVE OUTFLOW BOUNDARIES ARE LOCATED AHEAD OF THE FRONT FROM VA WWD INTO THE TN VALLEY AND CENTRAL PLAINS...AND THESE MAY PROVIDE ADDITIONAL FOCI FOR REDEVELOPMENT OF THUNDERSTORMS LATER TODAY. LASTLY...A NORTH-SOUTH DRY LINE IS EXPECTED TO BECOME BETTER ESTABLISHED THIS AFTERNOON ACROSS THE CENTRAL/SRN HIGH PLAINS. ...MID ATLANTIC STATES INTO CAROLINAS AND SRN APPALACHIANS... DYNAMIC FORCING FOR LARGE SCALE ASCENT ASSOCIATED WITH GREAT LAKES UPPER LOW IS EXPECTED TO SPREAD EWD ACROSS THIS REGION TODAY...ENHANCED BY MESOSCALE CONVERGENCE ALONG SURFACE TROUGH EXPECTED TO DEVELOP IN THE LEE OF THE APPALACHIANS. EARLY VISIBLE IMAGERY SHOWS CLEAR SKIES FROM THE DELMARVA ACROSS SERN VA INTO MUCH OF THE CAROLINAS. ALTHOUGH SOME CLOUDS ARE SPREADING EWD ACROSS THE APPALACHIANS BREAKS IN THE CLOUD COVER ARE LIKELY TO OCCUR. THIS WILL ALLOW STRONGER DIURNAL HEATING ACROSS PARTS OF THIS REGION TODAY WHERE DEW POINTS ARE EXPECTED TO INCREASE INTO THE 65-70F RANGE. 12Z REGIONAL SOUNDINGS EXHIBIT MODERATE STEEP LAPSE RATES WHICH WILL INCREASE MAGNITUDE OF INSTABILITY THIS AFTERNOON /MLCAPE OF 1500-2000 J/KG/. SEVERAL BANDS OF THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE LEE TROUGH EAST OF THE APPALACHIANS...AND ALONG/AHEAD OF THE COLD FRONT OVER WV/WRN VA/WRN PA REGION AS UPPER SYSTEM MOVES ACROSS THE AREA DURING THE AFTERNOON. STRONGEST DEEP LAYER SHEAR OF 30-35 KT IS EXPECTED ACROSS THE CAROLINAS NWD INTO THE DELMARVA REGION WHICH WILL ENHANCE STORM ORGANIZATION AND INTENSITY. A FEW SEVERE THUNDERSTORMS WILL BE POSSIBLE MAINLY THIS AFTERNOON AND EVENING WITH PRIMARY THREAT FOR DAMAGING WINDS AND LARGE HAIL. ADDITIONAL SEVERE STORMS MAY DEVELOP WWD INTO PARTS OF GA AND AL ALONG REMNANTS OF OUTFLOW BOUNDARIES ALONG SRN EDGE OF UPPER TROUGH WHERE UNSTABLE ENVIRONMENT (MLCAPE OF 2000-3000 J/KG) WILL BE LOCATED. ...MID SOUTH REGION... ANIMATED RADAR IMAGERY SUGGESTS MCS MOVING ACROSS SERN KS/NERN OK HAS GENERATED AN MCV. THIS FEATURE MAY CONTINUE MOVING SEWD TOWARD AR TODAY...WHERE 12Z LZK SOUNDING SHOWS VERY STEEP LAPSE RATE IN THE 800-550 MB LAYER. THE CAP IS EXPECTED TO GRADUALLY WEAKEN AS LOW LEVEL HEATING COUPLES WITH POSSIBLE ASCENT ASSOCIATED WITH THE UPSTREAM MCV...WITH POTENTIAL FOR THUNDERSTORMS TO REDEVELOP THIS AFTERNOON. STRONG INSTABILITY WITH MLCAPE OF 2000-3000 J/KG SUGGESTS THREAT FOR SEVERE THUNDERSTORMS ACROSS THIS AREA. ...CENTRAL/NRN PLAINS... ONGOING ELEVATED THUNDERSTORMS FROM SOUTH CENTRAL NEB INTO PARTS OF KS ARE EXPECTED TO CONTINUE MOVING EWD/ESEWD THIS MORNING. STRONGER CELLS IN KS MAY HAVE POTENTIAL TO PRODUCE HAIL. OTHER SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS FROM NERN CO NWD ACROSS WRN PARTS OF THE DAKOTAS AND ERN MT...AS WEAK PERTURBATIONS WITHIN STRENGTHENING SWLY FLOW ALOFT MOVE ACROSS WRN EDGE OF LOW LEVEL MOISTURE FIELD. 12Z SOUNDINGS SHOW STEEP MID LEVEL LAPSE RATES IN PLACE...AND CLEAR SKIES WILL PROMOTE STRONG INSOLATION WHICH WILL CONTRIBUTE TO DESTABILIZATION. DEEP LAYER SHEAR WILL BE THE STRONGEST OVER THE NRN HIGH PLAINS REGION WITH 40-50 KT IN THE LOWEST 6 KM...WITH SHEAR OF 30-35 KT EXTENDING SWD INTO THE CENTRAL PLAINS. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGH PLAINS AND MOVE NEWD LATE THIS AFTERNOON AND EVENING...WITH SOME OF THE ACTIVITY LIKELY PERSISTING INTO THE OVERNIGHT HOURS AS THE LOW LEVEL JET INTENSIFIES AFTER DARK. ...SRN HIGH PLAINS... VERY UNSTABLE ENVIRONMENT IS EVIDENT IN 12Z SOUNDINGS AT AMA AND MAF WITH NEARLY DRY ADIABATIC LAPSE RATES PRESENT ABOVE THE PBL. THIS WILL CONTRIBUTE TO STRONGLY UNSTABLE ENVIRONMENT EAST OF THE DRY LINE WHERE MLCAPE OF 2000-3000 J/KG IS EXPECTED. FORCING FOR LARGE SCALE ASCENT WILL BE MINIMAL AS THE UPPER RIDGE MOVES OVER THE AREA AND DRY LINE CONVERGENCE IS ALSO EXPECTED TO BE WEAK SUGGESTING THUNDERSTORM ACTIVITY WILL BE ISOLATED AT BEST. HOWEVER...THE 06Z ETA AND NAM-WRF PARALLEL AND THE 00Z EXPERIMENTAL HIGH RESOLUTION WRF-NMM ALL DEVELOP CONVECTION OVER PARTS OF WRN TX LATE THIS AFTERNOON/EVENING. GIVEN THE WEAK SHEAR A FEW PULSE STORMS OR MULTICELL CLUSTERS MAY DEVELOP WITH POTENTIAL FOR ISOLATED LARGE HAIL/DOWNBURSTS. ...SRN FL... WILL MAINTAIN LOW PROBABILITY FOR SEVERE STORMS ACROSS THIS AREA TODAY AS STRONGER BRANCH OF MID LEVEL FLOW IS FORECAST OVER THE AREA...ENHANCING DEEP LAYER SHEAR. PRIMARY THREAT IS EXPECTED OVER THE INTERIOR AND EAST COAST OF SOUTH FL AS STORMS PROGRESS EWD TOWARD EAST COAST SEA BREEZE FRONT. ..WEISS/JEWELL.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 16:41:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 12:41:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261631 SWODY1 SPC AC 261630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT FRI MAY 26 2006 VALID 261630Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NORTHERN AR...ACROSS THE TN VALLEY...INTO THE MID ATLANTIC AND SOUTHERN NEW ENGLAND STATES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CENTRAL AND NORTHERN PLAINS... ...SOUTHERN NEW ENGLAND INTO CAROLINAS... STRONG UPPER TROUGH WILL CONTINUE TO ROTATE EASTWARD INTO NY AND NEW ENGLAND TODAY...WITH BAND OF 40-50 KNOT WESTERLY FLOW EXTENDING ACROSS THE SOUTHERN APPALACHIANS AND CAROLINAS. VISIBLE SATELLITE IMAGERY SHOWS A LARGE AREA OF CLOUDINESS BENEATH UPPER SYSTEM ACROSS MUCH OF THE GREAT LAKES REGION AND OH VALLEY. HOWEVER...STRONG HEATING IS EXPECTED AHEAD OF LEADING EDGE OF CLOUDS ACROSS SOUTHERN NEW ENGLAND...AND OVER PARTS OF SOUTHEAST VA AND MUCH OF NC. THIS AREA IS LIKELY TO DESTABILIZE THROUGH THE EARLY AFTERNOON WITH MLCAPE VALUES OF AROUND 500 J/KG OVER NEW ENGLAND...AND 1000-2000 J/KG OVER VA/NC. SCATTERED THUNDERSTORMS ARE LIKELY TO DEVELOP OVER THIS AREA...WITH A THREAT OF DAMAGING WINDS AND HAIL IN STRONGER CELLS. POTENTIAL FOR ORGANIZED SEVERE STORMS OVER SOUTHERN NEW ENGLAND WILL BE MITIGATED BY LESS LOW LEVEL MOISTURE AND ONSHORE FLOW. ...AR/TN/MS/AL/GA... REMNANT OUTFLOW BOUNDARIES FROM OVERNIGHT CONVECTION EXTEND FROM STORMS OVER KS...ACROSS PARTS OF AR/TN INTO MS/AL/GA. BOUNDARIES ARE WEAKENING RAPIDLY THIS AFTERNOON...BUT MAY BECOME THE FOCUS FOR SCATTERED THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING. AMPLE MOISTURE AND MODERATELY/VERY UNSTABLE AIR MASS SUGGEST A THREAT OF HAIL AND DAMAGING WINDS IN STRONGER CELLS. UPPER RIDGE WILL BEGIN TO BUILD INTO WESTERN PARTS OF AREA AFTER 00Z...LIKELY DIMINISHING THREAT. ...NORTHERN/CENTRAL PLAINS... BROAD ZONE OF MODERATE SOUTHWESTERLY MID LEVEL FLOW IS PRESENT FROM KS INTO ND TODAY. STRONG DAYTIME HEATING WILL RESULT IN AFTERNOON TEMPERATURES IN THE 90S AND STEEP LOW/MID LEVEL LAPSE RATES THROUGHOUT THE REGION. DEEP MIXING IS EXPECTED TO RESULT IN SCATTERED THUNDERSTORM DEVELOPMENT BY LATE AFTERNOON ALONG WEST EDGE OF LOW LEVEL INSTABILITY ACROSS EASTERN WY. ACTIVITY IS FORECAST TO SPREAD EASTWARD INTO THE DAKOTAS/NEB/KS THROUGH THE EVENING. DAMAGING WINDS AND HAIL WILL BE THE MAIN THREATS. STRONGER LOW LEVEL BAROCLINIC ZONE IS FORECAST TO LIE ACROSS PARTS OF WESTERN NEB AND NORTHERN KS...WHERE ISOLATED SUPERCELLS AND PERHAPS TORNADOES MAY ALSO OCCUR. ...EASTERN MT... MODELS SUGGEST THAT MAIN SURFACE LOW WILL MOVE FROM EASTERN WY INTO ND THIS EVENING. NORTHEASTERLY UPSLOPE FLOW WILL RESULT ACROSS EASTERN AND SOUTH CENTRAL MT. SURFACE DEWPOINTS IN THE LOWER 50S AND FULL SUNSHINE MOST OF THE DAY WILL AID IN THE DEVELOPMENT OF MODERATE INSTABILITY AND SCATTERED EVENING STORMS. FORECAST SOUNDINGS SHOW SIGNIFICANT LOW LEVEL AND DEEP LAYER SHEAR ...FAVORABLE FOR SUPERCELLS CAPABLE OF LARGE HAIL. ...OH/PA/WV... BREAKS IN THE CLOUDS AND POCKET OF COOLER MID LEVEL TEMPERATURES WILL SUPPORT DEVELOPMENT OF SCATTERED THUNDERSTORMS THIS AFTERNOON. HAIL MAY OCCUR IN STRONGER CELLS BEFORE ACTIVITY WEAKENS THIS EVENING. ...SOUTH FL... VERY MOIST AND MODERATELY UNSTABLE AIR MASS IS PRESENT TODAY OVER SOUTH FL...BENEATH BRANCH OF STRONGER WESTERLY MID/UPPER LEVEL FLOW. CLOUDINESS SHOULD LIMIT DAYTIME HEATING IN THIS REGION. HOWEVER...CONDITIONAL THREAT WILL EXIST WITH ANY STORMS THAT CAN DEVELOP ACROSS AREA. LOCALLY DAMAGING WINDS WOULD LIKELY BE THE MAIN THREAT. ...SOUTHERN HIGH PLAINS... WATER VAPOR IMAGERY SHOWS A WEAK UPPER VORT MAX MOVING EASTWARD ACROSS WESTERN NM. THIS FEATURE WILL APPROACH THE SOUTHERN HIGH PLAINS THIS AFTERNOON AND EVENING NEAR TIME OF PEAK HEATING. SCATTERED THUNDERSTORMS MAY DEVELOP ALONG WEST EDGE OF STRONGER MOISTURE/INSTABILITY OVER WEST TX. WEAK VERTICAL SHEAR SHOULD LIMIT AREAL COVERAGE AND INTENSITY OF STORMS. ..HART/TAYLOR.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 19:47:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 15:47:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261944 SWODY1 SPC AC 261943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT FRI MAY 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-ATLANTIC/CAROLINAS WWD INTO THE MID-SOUTH... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL/NRN PLAINS... ...ERN STATES... WATER VAPOR IMAGERY SHOWS THE UPPER LOW ROTATING EWD INTO THE UPPER OH VLY THIS AFTN. MODEST H5 JET WRAPPING EWD BENEATH THE LOW WAS ENHANCING LARGE SCALE ASCENT ACROSS THE CAROLINAS. STRONG-SEVERE TSTMS HAVE BEEN FAVORING THE SEA-BREEZE AND LEE-TROUGH FROM SCNTRL VA SWD INTO THE CAROLINAS...ENHANCED BY THE LARGE SCALE LIFT. STRONG HEATING HAS CONTRIBUTED TO MLCAPES FROM 2000-3000 J/KG AND WILL BE SUPPORTIVE FOR VIGOROUS UPDRAFTS. THIRTY-40 KTS OF MEAN FLOW IN WELL-MIXED BOUNDARY LAYER WILL ENCOURAGE LARGE HAIL AND DAMAGING WINDS...ESPECIALLY FROM SERN VA INTO THE ERN CAROLINAS THROUGH THIS EVENING. MEANWHILE...RESIDUAL BOUNDARY LAYER MSTR BENEATH MINUS 12 DEGREE C H5 TEMPERATURES ASSOCD WITH THE UPPER LOW HAS BEEN FAVORABLE FOR SCT TSTMS FROM THE KY COALFIELDS NWD INTO THE UPPER OH VLY. SOME OF THESE TSTMS MAY ADVANCE EAST OF THE ALLEGHENY PLATEAU AND/OR DEVELOP ACROSS THE FOOTHILLS IN VA/MD THROUGH THE AFTN. ACTIVITY SHOULD BE LARGELY DIURNAL AND STRONGER UPDRAFTS WILL CONTAIN LARGE HAIL AND GUSTY WINDS. FARTHER N...CLOUDS AND PCPN HAVE UNDERMINED STRONG BOUNDARY LAYER DESTABILIZATION THIS AFTN THROUGHOUT CNTRL/ERN PA NEWD INTO SRN NEW ENGLAND. THIS COMBINED WITH POOR MID-TROP LAPSE RATES SUGGESTS THAT WIDESPREAD SEVERE WEATHER IS NOT LIKELY. ...NRN PLAINS... SFC LOW APPEARS TO BE CONSOLIDATING ACROSS CNTRL WY AT 19Z WITH BOUNDARY LAYER FLOW BACKING TO A MORE UPSLOPE COMPONENT IN NERN WY AND SCNTRL MT. THIS LOW-LEVEL TRAJECTORY SHOULD ADVECT 50S SFC DEW POINTS SWWD AND BE FAVORABLE FOR INCREASING MOUNTAIN TSTMS LATER THIS AFTERNOON. ACTIVITY SHOULD MOVE AND/OR DEVELOP NEWD ALONG/N OF THE BAROCLINIC ZONE INTO PARTS OF ND OVERNIGHT...ALONG SERN PERIPHERY OF THE UPSTREAM UPPER TROUGH. FAVORABLE VERTICAL SHEAR AND LAPSE RATES WILL EXIST FOR SUPERCELLS EVOLVING INTO LINE SEGMENTS CAPABLE OF MAINLY LARGE HAIL. ...CNTRL PLAINS... WATER VAPOR SHOWS A WEAK VORT MAX ROTATING NEWD THROUGH NCNTRL NM AND SCNTRL CO THIS AFTN. THIS HAS LIKELY ENHANCED THE DIURNAL UPSLOPE ACROSS THE CO/WY FRONT RANGE...MAINTAINING MODEST BOUNDARY LAYER MSTR TO THE MOUNTAINS. HEATING...UPSLOPE FLOW AND LARGE SCALE ASCENT WILL BE FAVORABLE FOR UPSCALE GROWTH OF MOUNTAIN TSTMS THROUGH THE EVENING AS THEY MOVE ONTO THE PLAINS. VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS...PRIMARILY EARLY IN THE TSTM LIFE-CYCLES WITH LARGE HAIL AND PERHAPS A TORNADO OR TWO. EVOLUTION INTO AN MCS IS LIKELY OVERNIGHT FROM NERN CO/SERN WY ACROSS NEB AND SRN SD. HERE...THE LLJ AXIS IS EXPECTED TO IMPINGE ON A NW-SE ORIENTED WARM FRONT...MAXIMIZING LOW/MID-LEVEL WARM ADVECTION. LARGE HAIL MAY ACCOMPANY THE STRONGER STORMS OWING TO THE STEEP MID-TROPOSPHERIC LAPSE RATES. ...SRN HIGH PLAINS... A PATCH OF MID-LEVEL MSTR WAS EVIDENT ACROSS THE TX HIGH PLAINS ON SATL IMAGERY. GIVEN VERY HOT BOUNDARY LAYER TEMPERATURES AND LOW-LEVEL CONVERGENCE ALONG THE DRYLINE/LEE-TROUGH...CINH SHOULD ERODE SUFFICIENTLY FOR THE POTENTIAL FOR TSTMS WITHIN THE MID-CLOUD LATER THIS AFTN. VERTICAL SHEAR 30-40 KTS WILL BE FAVORABLE FOR SUPERCELLS AND WELL-MIXED BOUNDARY LAYER WILL ENCOURAGE MICROBURSTS. COVERAGE SHOULD REMAIN ISOLD. ...CNTRL/SRN FL... WEAK SEABREEZE WAS THE FOCUS FOR TSTM INITIATION ACROSS CNTRL/SRN FL EARLY THIS AFTN. THROUGH THE REMAINDER OF PEAK HEATING... LOCALIZED OUTFLOW BOUNDARIES WILL BE IMPETUS FOR NEW UPDRAFTS. MAIN THREAT WILL BE HEAVY RAIN...THOUGH MODEST MID-LEVEL LAPSE RATES WILL FAVOR MARGINALLY SEVERE HAIL. ACTIVITY WILL DIMINISH AFTER SUNDOWN. ..RACY.. 05/26/2006  From swody1 at goshenarc.org Sat May 27 01:07:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 21:07:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270106 SWODY1 SPC AC 270105 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT FRI MAY 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL AND NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE TN VALLEY...MID MS VALLEY...SRN APPALACHIANS...CAROLINAS AND VA... ...CNTRL AND NRN PLAINS... WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A SOUTHWEST FLOW PATTERN OVER THE NCNTRL US WITH SEVERAL MINOR SHORTWAVE TROUGHS EMBEDDED IN THE FLOW. SEVERAL MCS CLUSTERS ARE DEVELOPING ON THE WRN EDGE OF AN AXIS OF MODERATE INSTABILITY LOCATED FROM SRN NEB EXTENDING NWD INTO THE WCNTRL DAKOTAS. AS THE CONVECTION MOVES NEWD INTO INCREASING INSTABILITY...STORM COVERAGE SHOULD EXPAND DUE TO THE WIDESPREAD LARGE-SCALE ASCENT AND INCREASING LOW-LEVEL JET LATE THIS EVENING. AS A RESULT...A COUPLE OF OVERNIGHT MCS CLUSTERS SHOULD DEVELOP WITH ONE MCS LIKELY NEAR A LOW-LEVEL JET MAX IN ND AND ANOTHER LIKELY IN THE NOSE OF A SECONDARY LOW-LEVEL JET MAX IN CNTRL AND ERN NEB. FORECAST SOUNDINGS ACROSS THE CNTRL AND NRN PLAINS THIS EVENING SHOW MODERATE VERTICAL SHEAR PROFILES IN PLACE DUE TO STRONG DIRECTIONAL SHEAR. AS LOW-LEVEL FLOW INCREASES OVERNIGHT...THE VERTICAL SHEAR SHOULD BECOME ENHANCED WITH A CONTINUED THREAT OF SUPERCELLS. A FEW TORNADOES WILL BE POSSIBLE ESPECIALLY ACROSS NEB ON THE NOSE OF A 45 KT LOW-LEVEL JET WHICH IS FORECAST TO ENHANCE THE LOW-LEVEL SHEAR OVERNIGHT. IN ADDITION...STEEP LAPSE RATES WILL ALSO MAKE LARGE HAIL LIKELY WITH SUPERCELLS THAT PERSIST. THE WIND DAMAGE POTENTIAL MAY ALSO INCREASE AS CELLS MERGE AND MCS DEVELOPMENT OCCURS ACROSS THE REGION OVERNIGHT. ...MID MS AND TN VALLEYS/SRN APPALACHIANS/CAROLINAS... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL TROUGH LOCATED ALONG THE ERN SEABOARD. AT THE SFC...A COLD FRONT IS LOCATED ACROSS THE SRN APPALACHIAN MTNS AND A MODERATELY UNSTABLE AIRMASS EXISTS AHEAD OF THE FRONT. STORMS SHOULD REMAIN SUSTAINED LATE THIS EVENING ACROSS THE WARM SECTOR DUE TO WIDESPREAD LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-TROUGH. THE GREATEST COVERAGE OF STORMS SHOULD BE IN THE ERN CAROLINAS AS A 40-45 LOW-LEVEL JET EXPANDS LATE THIS EVENING. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES WHICH COMBINED WITH THE INSTABILITY SHOULD CONTINUE TO BE FAVORABLE FOR SUPERCELLS. STEEP LAPSE RATES SHOWN ON FORECAST SOUNDINGS SUGGEST LARGE HAIL AND WIND DAMAGE WILL BE LIKELY WITH THE STRONGER CELLS LATE THIS EVENING. HOWEVER...THE SEVERE THREAT SHOULD DECREASE AFTER MIDNIGHT AS INSTABILITY WEAKENS ACROSS THE REGION. ..BROYLES.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 06:03:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 02:03:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270602 SWODY1 SPC AC 270600 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT SAT MAY 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...NRN PLAINS... AN UPPER-LOW AND ASSOCIATED TROUGH WILL DRIFT EWD INTO THE NRN ROCKIES AND FOUR CORNERS REGION THROUGH SATURDAY. SWLY FLOW WILL REMAIN IN PLACE ACROSS THE NRN PLAINS AS MID-LEVEL FLOW GRADUALLY STRENGTHENS ACROSS THE REGION. AHEAD OF THE TROUGH...WIDESPREAD LARGE-SCALE ASCENT WILL SUPPORT THUNDERSTORM DEVELOPMENT SATURDAY AFTERNOON NEAR A SFC LOW AND FRONTAL BOUNDARY EXTENDING ENEWD ACROSS NRN ND. SFC DEWPOINTS NEAR 60 F SHOULD RESULT IN STRONG INSTABILITY ALONG AND SOUTH OF THE BOUNDARY. AS STORMS ORGANIZE AND MOVE EWD ALONG THE GRADIENT IN INSTABILITY...MCS DEVELOPMENT APPEARS LIKELY BY SATURDAY EVENING ACROSS NRN AND ERN ND INTO NRN MN. FORECAST SOUNDINGS ACROSS THE REGION LATE SATURDAY AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES WITH STEEP MID-LEVEL LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. BECAUSE OF THE VERY UNSTABLE AIRMASS...VERY LARGE HAIL WILL ALSO BE POSSIBLE WITH THE STRONGER SUPERCELLS. IN ADDITION...A FEW TORNADOES MAY OCCUR WITH SUPERCELLS THAT PARALLEL THE BOUNDARY AS AN IMPRESSIVE 45-55 KT LOW-LEVEL JET STRENGTHENS IN THE LATE AFTERNOON AND EARLY EVENING. A STRONG TORNADO REMAINS POSSIBLE NORTHEAST OF THE SFC LOW ESPECIALLY IF STORMS REMAIN DISCRETE AND SFC DEWPOINTS REACH THE LOWER 60S F ACROSS NERN ND BY LATE AFTERNOON. IF STORMS DEVELOP INTO A LINEAR ORIENTATION...THEN THE WIND DAMAGE THREAT WOULD ALSO BE ENHANCED IN THE EVENING. AN ISOLATED SEVERE THREAT MAY CONTINUE OVERNIGHT AS THE MCS TRACKS EWD ACROSS NRN MN CONSIDERING THE AMOUNT OF INSTABILITY FORECAST ACROSS THE REGION. ...SRN PLAINS... SOUTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE SRN PLAINS THROUGH SATURDAY. AT THE SFC...A TROUGH IS FORECAST TO BE LOCATED ACROSS WRN KS AND WEST TX WITH DEWPOINTS EAST OF THE TROUGH IN THE 60S F. THIS SHOULD RESULT IN MODERATE TO STRONG INSTABILITY BY LATE AFTERNOON EAST OF THE TROUGH. A CAPPING INVERSION SHOULD WEAKEN ENOUGH BY LATE AFTERNOON FOR THE INITIATION OF A FEW ISOLATED STORMS ACROSS WRN KS...WRN OK...THE ERN TX PANHANDLE AND WCNTRL TX. ALTHOUGH FORECAST SOUNDINGS SHOW 0-6 KM SHEAR VALUES GENERALLY BELOW 3O KT...THE STEEP LAPSE RATES AND AMOUNT OF INSTABILITY MAY BE ENOUGH FOR A FEW MARGINALLY SEVERE STORMS IN THE LATE AFTERNOON OR EARLY EVENING. ...SERN STATES... AN UPPER-LEVEL RIDGE WILL BE IN PLACE ACROSS THE OH AND TN VALLEYS THROUGH SATURDAY. AT THE SFC...A BOUNDARY IS FORECAST TO BE IN PLACE FROM WRN TN EXTENDING SEWD ACROSS AL AND GA. AS SFC TEMPS WARM SATURDAY...CONVECTION SHOULD INITIATE ALONG THE BOUNDARY AND MOVE SWD ACROSS THE REGION. FORECAST SOUNDINGS SHOW MODERATE TO STRONG INSTABILITY WITH WEAK VERTICAL SHEAR PROFILES. THIS SUGGESTS STORM MODE WILL BE PULSE IN NATURE. ALTHOUGH A CLUSTER OF STORMS WITH HAIL AND/OR ISOLATED WIND DAMAGE MAY STILL OCCUR...IT IS TOO EARLY TO IDENTIFY AN AREA WITH ENHANCED SEVERE POTENTIAL. UPGRADE TO SLIGHT RISK MAY BE NECESSARY ACROSS PARTS OF THE REGION ONCE THE AMOUNT OF INSTABILITY AND LOCATION OF MCS DEVELOPMENT BECOMES MORE CERTAIN. ..BROYLES.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 13:05:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 09:05:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271303 SWODY1 SPC AC 271301 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0801 AM CDT SAT MAY 27 2006 VALID 271300Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN PLAINS INTO NWRN MN... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF IL... ...SYNOPSIS... AMPLIFIED FLOW PATTERN IS FORECAST TO PERSIST TODAY AS DEEPENING UPPER TROUGH OVER THE PACIFIC COAST STATES MOVES SLOWLY EWD TOWARD THE INTERMOUNTAIN REGION...AND UPPER RIDGE BUILDS INTO THE ERN STATES IN THE WAKE OF THE DEPARTING TROUGH ALONG THE ATLANTIC COAST. AT THE SURFACE...LOW PRESSURE IS EXPECTED TO REMAIN OVER THE NORTHERN HIGH PLAINS TODAY WITH A QUASISTATIONARY FRONT EXTENDING NEWD INTO SERN MANITOBA/NWRN ONTARIO...WHILE A COLD FRONT EXTENDING SWWD INTO WY AND UT MOVES SLOWLY SEWD. A NORTH/SOUTH DRY LINE WILL CONTINUE OVER THE CENTRAL/SRN HIGH PLAINS. IN THE EAST...A WEAK COLD FRONT WILL MOVE SWD ACROSS THE CAROLINAS...THEN RETURN NWWD AS A WARM FRONT THROUGH THE TN VALLEY TOWARD THE UPPER MS VALLEY. ...NRN PLAINS... STEEP MID LEVEL LAPSE RATES WILL REMAIN OVER THE REGION TODAY ABOVE INCREASINGLY MOIST BOUNDARY LAYER ALONG/SOUTH OF THE FRONT...RESULTING IN VERY UNSTABLE ENVIRONMENT WITH MLCAPE OF 2000-3500 J/KG THIS AFTERNOON AND EVENING. WARM LAYER ABOVE 850 MB IN WARM SECTOR SOUNDINGS IS EXPECTED TO INHIBIT CONVECTIVE DEVELOPMENT INTO THE AFTERNOON...WITH GREATER THREAT FOR CONVECTION DEVELOPING ALONG/NORTH OF THE FRONT LATER THIS AFTERNOON AND EVENING IN RESPONSE TO STRENGTHENING CONVERGENCE AND WARM ADVECTION ASSOCIATED WITH LOW LEVEL JET. ALTHOUGH STRONGEST SWLY FLOW ALOFT IS FORECAST TO LAG WELL TO THE WEST OF THE WARM SECTOR...VERTICAL SHEAR NEAR THE FRONT WILL BE SUFFICIENTLY STRONG TO ENHANCE CONVECTIVE ORGANIZATION AND PROMOTE DEVELOPMENT OF A FEW SUPERCELLS. PARTS OF CENTRAL AND ERN ND...ESPECIALLY ALONG/NORTH OF THE FRONT...APPEAR TO HAVE GREATEST SEVERE POTENTIAL WITH THE POSSIBILITY OF STORMS PRODUCING VERY LARGE HAIL AND A FEW TORNADOES...IN ADDITION TO DAMAGING WIND GUSTS. THIS ACTIVITY IS EXPECTED TO MOVE NEWD TONIGHT WITH ISOLATED SEVERE STORMS POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...ERN NEB/IA INTO IL AREA... RADAR IMAGERY INDICATES TWO MCV'S ASSOCIATED WITH MORNING CONVECTION...WITH BETTER-DEFINED MCV MOVING EWD INTO ERN IA AND TRAILING CIRCULATION MOVING FROM ERN NEB INTO EXTREME WRN IA. THUNDERSTORMS ALONG LEADING EDGE OF ERN IA MCV HAVE WEAKENED...BUT ADDITIONAL STORMS HAVE DEVELOPED WWD ACROSS NWRN MO INTO ERN NEB NORTH OF THE EARLIER OUTFLOW BOUNDARY. 12Z TOP SOUNDING EXHIBITS STEEP LAPSE RATE ABOVE 680 MB WITH MORE THAN 2000 J/KG OF ELEVATED CAPE FOR PARCELS ORIGINATING AROUND 750 MB....SUGGESTING A THREAT FOR HAIL WITH STRONGER CELLS. ACTIVITY IS LIKELY TO SPREAD EWD ACROSS EXTREME NRN MO/EXTREME SRN IA INTO MID MORNING BEFORE WEAKENING AFTER IT MOVES EAST OF THE LOW LEVEL JET. NEW THUNDERSTORMS ARE EXPECTED TO DEVELOP DOWNSTREAM FROM THE LEAD MCV THIS AFTERNOON AS IT MOVES SLOWLY EWD TODAY AND INTERACTS WITH INCREASINGLY MOIST/UNSTABLE ENVIRONMENT OVER PARTS OF NRN/CENTRAL IL. COMBINATION OF AMPLE LOW LEVEL MOISTURE /SURFACE DEW POINTS REACHING 65-70F/ AND STRONG INSOLATION WILL CONTRIBUTE TO DESTABILIZATION WITH MLCAPE 1500-2500 J/KG. THUNDERSTORMS ARE EXPECTED TO INCREASE IN INTENSITY THIS AFTERNOON/EVENING WITH THREAT FOR LARGE HAIL AND DAMAGING WIND GUSTS. ...TN VALLEY INTO SERN STATES... MOIST UNSTABLE AIR MASS IS EXPECTED TO CONTINUE ALONG/SOUTH OF THE FRONT THAT IS FORECAST TO MOVE SWD ACROSS THE CAROLINAS INTO GA. STRONG DIURNAL HEATING COUPLED WITH A WEAK CAP WILL RESULT IN SCATTERED AREAS OF THUNDERSTORMS DEVELOPING THIS AFTERNOON. WEAK VERTICAL SHEAR SUGGESTS PULSE STORMS WILL BE THE DOMINANT CONVECTIVE TYPE WITH POTENTIAL FOR ISOLATED BRIEF WET MICROBURSTS AND HAIL WITH STRONGER STORMS. ...CENTRAL/SRN HIGH PLAINS... UNSTABLE AIR MASS IS EXPECTED TO PERSIST ALONG/EAST OF THE DRY LINE THIS AFTERNOON. HOWEVER...WEAK LOW LEVEL CONVERGENCE WITHIN A CAPPED ENVIRONMENT AND MINIMAL FORCING FOR LARGE SCALE ASCENT WILL LIKELY TO INHIBIT CONVECTIVE DEVELOPMENT. ALTHOUGH MOST MODELS EXCEPT PARALLEL NAM GENERATE LITTLE IF ANY CONVECTION IN THE HIGH PLAINS...FORECAST SOUNDINGS INDICATE CIN WILL GRADUALLY DIMINISH DURING MAXIMUM HEATING PERIOD WILL WELL-MIXED BOUNDARY LAYER DEVELOPING. THIS SUGGESTS THAT A LOW PROBABILITY FOR THUNDERSTORMS SHOW BE MAINTAINED WITH COINCIDENT THREAT FOR ISOLATED SEVERE CELLS ALONG/EAST OF DRY LINE. ..WEISS/GUYER.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 16:31:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 12:31:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271626 SWODY1 SPC AC 271624 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT SAT MAY 27 2006 VALID 271630Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF WEST TX AND SOUTHWEST OK... ...DAKOTAS AND NWRN MN... UPPER TROUGH OVER THE WESTERN STATES CONTINUES TO AMPLIFY TODAY...WHILE UPPER RIDGE BUILDS OVER THE CENTRAL AND EASTERN U.S. MAIN SURFACE LOW WILL DEVELOP FROM NORTHEAST WY ACROSS SD INTO ND TONIGHT...ALONG SURFACE WARM FRONT. MODEL SOUNDINGS IN THIS AREA SHOW STEEP LOW AND MID LEVEL LAPSE RATES AND MLCAPE VALUES OVER 3500 J/KG. SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP AHEAD OF LOW FROM BLACK HILLS REGION INTO CENTRAL/WESTERN ND...MAINLY AFTER 00Z. SUPERCELLS CAPABLE OF LARGE HAIL/DAMAGING WINDS AND PERHAPS ISOLATED TORNADOES ARE EXPECTED. STORMS MAY SPREAD EASTWARD DURING THE LATE EVENING INTO NORTHWEST MN. DEVELOPMENT FARTHER SOUTH IS EXPECTED TO BE PRECLUDED BY CAPPING INVERSION AND WARM TEMPERATURES ALOFT. ...MN/WI/IA/IL... CLUSTER OF THUNDERSTORMS IS ONGOING THIS MORNING OVER SOUTHWEST IA. THIS ACTIVITY IS JUST NORTH OF REMNANT OUTFLOW BOUNDARY...AND ON NOSE OF STRONGER SOUTHERLY LOW LEVEL JET. WARMING TEMPERATURES ALOFT SHOULD TEND TO WEAKEN STORMS IN THIS REGION BY EARLY AFTERNOON. HOWEVER...NEW STORMS MAY DEVELOP FARTHER NORTHEASTWARD INTO PARTS OF MN/WI/IA AND NORTHERN IL AS MCV DRIFTS INTO AREA. MODELS AGREE ON DEVELOPING MODERATE-STRONG INSTABILITY IN THIS REGION...FAVORABLE FOR HAIL AND GUSTY WINDS. MODELS ALSO SUGGEST THAT ACTIVITY MAY PERSIST MUCH OF THE NIGHT DUE TO STRENGTHENING NOCTURNAL LOW LEVEL JET AND ENHANCED LOW LEVEL WARM ADVECTION. ...WEST TX INTO SOUTHWEST OK... DIFFUSE DRYLINE IS EXPECTED TO BECOME ESTABLISHED THIS AFTERNOON FROM SOUTHWEST OK INTO THE BIG BEND REGION OF TX. HOT SURFACE TEMPERATURES APPROACHING 100F...COUPLED WITH DEWPOINTS NEAR 60F EAST OF DRYLINE...WILL RESULT IN A ZONE OF HIGH INSTABILITY /MLCAPE VALUES OF 2000-3000 J/KG/. FORECAST SOUNDINGS SHOW A DEEP MIXED BOUNDARY LAYER AND NO CAP...LIKELY RESULTING IN SCATTERED THUNDERSTORM DEVELOPMENT NEAR/JUST AFTER PEAK HEATING. WATER VAPOR IMAGERY HINTS AT A WEAK UPPER FEATURE MOVING INTO WEST TX. THIS MAY HELP TO ORGANIZE CONVECTION AND ENHANCE THREAT OF LOCALLY DAMAGING WINDS AND HAIL IN STRONGER CELLS. THUS...HAVE INTRODUCED A SLIGHT RISK FOR THIS AREA. ...TN VALLEY INTO THE SOUTHEAST... WEAK SURFACE BOUNDARY CURRENTLY EXTENDS FROM SC/GA INTO IL. AIR MASS ALONG AND SOUTH OF BOUNDARY REMAINS VERY MOIST/UNSTABLE WITH AFTERNOON MUCAPE VALUES EXPECTED TO RANGE FROM 3000-4000 J/KG. VERTICAL SHEAR PROFILES ARE WEAK IN THIS AREA. HOWEVER...ISOLATED PULSE OR MULTICELL SEVERE STORMS ARE POSSIBLE ALONG THIS AXIS. THREAT SHOULD SUBSIDE BY EARLY EVENING. ...SOUTH FL... SUBTROPICAL JET REMAINS ACROSS SOUTH FL TODAY...WITH WATER VAPOR IMAGERY SHOWING WELL-DEFINED SHORTWAVE TROUGH OVER THE CENTRAL GULF OF MEXICO. AMPLE MOISTURE/INSTABILITY ARE PRESENT OVER THIS REGION...LIKELY LEADING TO SCATTERED AFTERNOON THUNDERSTORMS. SUFFICIENT UPPER LEVEL WIND FIELDS AND FAVORABLE THERMODYNAMIC PARAMETERS SUGGEST A THREAT OF GUSTY WINDS AND HAIL IN STRONGER CELLS. ..HART/TAYLOR.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 20:00:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 16:00:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271959 SWODY1 SPC AC 271957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT SAT MAY 27 2006 VALID 272000Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN PLAINS TO THE UPPER MS VLY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN GA AND SRN SC... ...NRN PLAINS... 19Z SFC ANALYSIS PLACES A SFC LOW SW OF KBIS WITH A FRONT SITUATED FROM CYWG-KDIK-KGCC. 18Z BIS RAOB SHOWED SUBSTANTIAL CINH IN THE WARM SECTOR WITH H7 TEMPERATURES AOA 12 DEGREES C AND CONVECTIVE TEMPERATURES IN THE MID 90S. PROFILERS/VWPS SEEM TO SUGGEST THAT A SPEED MAX IS DEVELOPING NEWD THROUGH THE CNTRL ROCKIES AND MAY BE AIDING HIGH BASED CONVECTION ACROSS THE SANDHILLS OF NEB AND ECNTRL WY. AS THIS FEATURE MOVES INTO THE DAKS LATER THIS EVENING...TSTMS ARE APT TO DEVELOP. QUESTION REMAINS IF STORMS WILL DEVELOP IN THE WARM SECTOR OR ON THE COLD SIDE OF THE FRONT. MOST LIKELY SCENARIO WOULD BE FOR NOCTURNAL STORMS TO FORM ATOP THE COLDER AIR ACROSS THE HIGHER PLAINS WITH THREATS FOR LARGE HAIL. BUT...THERE WILL BE A CONDITIONAL THREAT FOR MORE SFC-BASED STORMS TO DEVELOP ALONG THE EDGE OF THE STRONGER CAP IN EXTREME NRN SD AND CNTRL/ERN ND THIS EVE. 0-6KM SHEAR IN THE WARM SECTOR WAS WEAK...BUT MAGNITUDE OF LAPSE RATES SUGGEST ANY STORM COULD EVOLVE INTO SUPERCELLS WITH LARGE HAIL...HIGH WINDS AND A TORNADO OR TWO. EVOLUTION INTO A NOCTURNAL MCS SEEMS REASONABLE AS THE LLJ ACCELERATES...CROSSING THE RED RVR VLY BY EARLY SUNDAY MORNING. ...UPPER MS VLY... DIFFERENTIAL HEATING ON THE PERIPHERY OF A MORNING CORN BELT MCS HAS DESTABILIZED THE BOUNDARY LAYER ACROSS THE UPPER MS VLY. THIS HAS CONTRIBUTED TO INCREASING DEEP MOIST CONVECTION DOWNSTREAM... ARCING FROM ECNTRL MN THROUGH CNTRL WI...THEN SWWD INTO NRN IL. ACTIVITY SHOULD CONTINUE TO SPREAD RADIALLY OUTWARD...REACHING UPPER MI AND SRN WI...NRN IL THROUGH THE NIGHT. AT LEAST THROUGH MID-EVENING...STORMS MAY CONTAIN LARGE HAIL AND DAMAGING WIND GUSTS. ...SRN HIGH PLAINS... MODEST BOUNDARY LAYER MSTR HAS BEEN MAINTAINED ALONG/E OF THE CAPROCK SWD INTO THE LWR TRANSPECOS VLY AND THE BIG BEND REGION. TSTMS HAVE INITIATED...PRIMARILY OVER THE DAVIS...DEL NORTE MOUNTAINS OF SW TX. FARTHER N...A PERSISTENT CU FIELD WAS EVIDENT OVER THE LOW ROLLING PLAINS AND BENEATH A MID-LEVEL CLOUD PATCH OVER THE SRN HIGH PLAINS OF W TX. AS THE BOUNDARY LAYER CONTINUES TO HEAT...TSTMS WILL THRIVE NEAR THE SW TX MOUNTAINS AND PROBABLY INITIATE FARTHER N INVOF CAPROCK FROM JUST E OF KLBB SWD AFTER 22Z...AIDED BY A WEAK DISTURBANCE ALOFT. EFFECTIVE VERTICAL SHEAR IS EXPECTED TO REMAIN WEAK...BUT MAGNITUDE OF LAPSE RATES WILL FAVOR SLOW MOVING SUPERCELLS...SHOULD A STORM BECOME ESTABLISHED. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE THREATS. ACTIVITY SHOULD DIMINISH AFTER DARK. ...MID-SOUTH TO THE SERN STATES... NW-SE ORIENTED FRONT LIES FROM WRN TN ACROSS NRN AL TO THE SAV RVR VLY. SCT TSTMS HAVE BEEN FAVORING THIS ZONE OF CONVERGENCE AND WILL LIKELY CONCENTRATE ACROSS THE SAV RVR VLY VCNTY COLDER TEMPERATURES ALOFT AND ACROSS THE TN VLY TIED TO A WEAK MCV. VERTICAL SHEAR WAS VERY WEAK ACROSS THE REGION...BUT THE AIR MASS WAS QUITE UNSTABLE. THUS...ISOLD MULTICELL PULSE SEVERE STORMS CAN BE EXPECTED GIVING LOCAL DAMAGING WIND GUSTS OR HAIL. ACTIVITY SHOULD DIMINISH THIS EVENING. ...CNTRL/SRN FL... SLIGHTLY STRONGER AMBIENT BOUNDARY LAYER FLOW TODAY DELAYED THE SEA-BREEZE...BUT 19Z VSBL SATL SHOWS TSTMS BEGINNING TO INCREASE ACROSS CNTRL/SRN FL. GIVEN PRESENCE OF A WEAK VORT MAX MOVING ACROSS THE CNTRL/SRN PORTIONS OF THE STATE...RELATIVELY STEEP MID-LEVEL LAPSE RATES AND MOIST BOUNDARY LAYER...ISOLD STRONG-SEVERE STORMS CAN BE EXPECTED. STORMS SHOULD MOVE EWD TOWARD THE ECOAST DURING THE EVENING WITH ISOLD DAMAGING WINDS AND HAIL. ..RACY.. 05/27/2006  From swody1 at goshenarc.org Sun May 28 01:14:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 21:14:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280113 SWODY1 SPC AC 280111 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0811 PM CDT SAT MAY 27 2006 VALID 280100Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS SRN HIGH PLAINS... ...NRN HIGH PLAINS... POTENT LEE-SIDE CYCLONE IS FORECAST TO TRACK NEWD ALONG INTENSE BAROCLINIC ZONE SITUATED FROM WRN SD THROUGH CNTRL ND THROUGH EARLY SUNDAY. VERY HOT AND UNSTABLE AIR MASS WAS PRESENT ACROSS CNTRL DAKOTAS AND WILL FUEL NUMEROUS SEVERE STORMS...PRIMARILY ACROSS ND WHERE FORCING CAN OVERCOME STRONG CAP/INHIBITION SITUATED ACROSS THE BULK OF THE GREAT PLAINS. GIVEN STRENGTH OF LOW LEVEL JET/SHEAR AND MASS INFLOW INTO THE DEVELOPING STORMS...SUPERCELLS WITH LARGE HAIL AND HIGH WINDS APPEAR LIKELY. TORNADO POTENTIAL WILL ALSO EXIST FOR DISCRETE CELLS TRACKING NEAR THE FRONTAL BOUNDARY OVER THE NEXT FEW HOURS. ...NERN IA/MN/WI... STRONG STORMS HAVE BEEN REDEVELOPING ACROSS WI...IN THE WAKE OF EARLIER MCS NOW DECAYING ACROSS LAKE MI/UPPER MI. BROADLY DIFFLUENT FLOW ALOFT AND INCREASING LIFT/WAA ACROSS THE REGION SHOULD SUPPORT ADDITIONAL DEVELOPMENT...OR SUSTAIN ONGOING CONVECTION OVER THE NEXT SEVERAL HOURS. NEAR SURFACE-BASED DEVELOPMENT HAS RECENTLY FORMED ON THE NRN EDGE OF INTENSE INSTABILITY ACROSS NERN IA WHERE DIAGNOSTIC DATA INDICATES SUFFICIENT EFFECTIVE SHEAR EXISTS FOR SUPERCELLS. DESPITE SOME INHIBITION INDICATED ON EVENING SOUNDINGS FROM IA/MN...CONTINUED STRONG WAA OVER THIS AREA...COUPLED WITH PRESENCE OF VERY STEEP LAPSE RATES...SHOULD RESULT IN AN INCREASING CHANCE OF SCATTERED SEVERE HAIL OVERNIGHT...AND PERHAPS A BRIEF TORNADO WHERE LOW LEVEL FLOW IS BACKED IN THE WAKE OF EARLIER MCS. ...SRN HIGH PLAINS... WEAK HEIGHT FALLS/BACKGROUND ASCENT ROTATING OUT AHEAD OF THE LARGE SCALE WRN TROUGH...AND STRONG DEEP-LAYER HEATING/MIXING HAVE PROMOTED A NUMBER OF SEVERE HIGH-BASED TSTMS FROM THE RIO GRANDE NWD TO THE TX/OK PNHDLS. BAND OF 30KT WLY MID LEVEL FLOW ATOP WEAK SLY/VARIABLE FLOW WITHIN DEEP BOUNDARY LAYER WAS RESULTING IN ADEQUATE SHEAR FOR A FEW SUSTAINED ROTATING UPDRAFTS. HAIL AND HIGH WINDS SHOULD ACCOMPANY THIS ACTIVITY FOR AT LEAST A FEW MORE HOURS. IT IS POSSIBLE A SMALL MCS OR TWO COULD EVOLVE AS ACTIVITY DRIFTS GRADUALLY EAST INTO STRONGER INSTABILITY THROUGH THE EVENING. HOWEVER...STRONG INHIBITION...AND MASS INFLOW DIRECTED AWAY FROM THE REGION AND INTO THE STRONGER SYSTEM ACROSS THE NRN PLAINS...SHOULD LIMIT OVERALL SEVERE STORM COVERAGE LATER TONIGHT. ..CARBIN.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 05:58:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 01:58:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280557 SWODY1 SPC AC 280555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 28 2006 VALID 281200Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM WRN/NRN NEB ACROSS THE ERN DAKOTAS AND WRN MN... ...SYNOPSIS... STRONGLY AMPLIFIED MID/UPPER LEVEL FLOW PATTERN WILL FEATURE A LARGE SUMMER-LIKE RIDGE ACROSS MUCH OF THE EAST...AND A RELATIVELY DEEP TROUGH ACROSS THE WEST AND ROCKIES. SHORT WAVE IMPULSES EMANATING FROM THE WRN TROUGH AND ENCOUNTERING STRONG DOWNSTREAM RIDGING HAVE BEEN LIFTING NNEWD/NEWD ACROSS THE HIGH PLAINS AND UPPER MS VALLEY OVER THE WEEKEND AND DRIVING MCS DEVELOPMENT ACROSS THESE AREAS...AS WELL AS ACROSS SCNTRL CANADA. EXTENSIVE PLUME OF WARM AIR ALOFT COVERING MUCH OF THE GREAT PLAINS AND PARTS OF THE MIDWEST HAS LIMITED MORE WIDESPREAD TSTM DEVELOPMENT OVER THESE REGIONS DESPITE PRONOUNCED DIURNAL DESTABILIZATION. SIMILAR CONDITIONS WILL PERSIST TODAY. A STRONG IMPULSE/SPEED MAX CURRENTLY CROSSING THE SRN GREAT BASIN IS FORECAST TO PIVOT NEWD AROUND THE ERN FLANK OF THE LARGE SCALE WRN TROUGH AND PRODUCE MODEST HEIGHT FALLS FROM CO TO THE WRN DAKOTAS THROUGH SUNDAY NIGHT. SHARP BAROCLINIC ZONE...ALIGNED WITH DEEP-LAYER MERIDIONAL FLOW FROM CO TO ND...WILL PROVIDE FOCUS FOR TRIPLE POINT LOW FORMATION ON COLD FRONT/DRYLINE/STATIONARY FRONT INTERSECTION NERN CO TO WRN/CNTRL NEB PNHDL DURING LATE AFTERNOON AS WRN IMPULSE APPROACHES. ANOTHER SURFACE LOW WILL BE SITUATED ON THE BOUNDARY OVER ERN ND...ASSOCIATED WITH A LEADING IMPULSE LIFTING INTO SRN CANADA. THE ND LOW IS FORECAST TO TRACK INTO SRN MANITOBA THROUGH THE EVENING WHILE CO/NEB SURFACE LOW MOVES NEWD ACROSS TO NRN NEB...AND THEN TO ERN SD/WRN MN THROUGH MONDAY MORNING. COLD FRONT ASSOCIATED WITH THE NEB LOW WILL SURGE SWD ACROSS THE CNTRL HIGH PLAINS TO SWRN KS BY THE END OF THE FORECAST PERIOD. ...NEB/DAKOTAS... VERY STRONG TO EXTREME WARM SECTOR INSTABILITY WILL AGAIN DEVELOP FROM CNTRL/ERN NEB NWD ACROSS ND/MN THIS AFTERNOON WITH MLCAPE VALUES IN THIS CORRIDOR AOA 2500 J/KG. DESPITE TEMPERATURES CLIMBING INTO THE 90S ACROSS THE WARM SECTOR...CONVECTIVE INHIBITION WILL AGAIN LIMIT SURFACE-BASED STORM DEVELOPMENT TO THOSE AREAS WHERE EITHER EXCESSIVE HEATING/MIXING...AND/OR PERSISTENT STRONG FORCING CAN OVERCOME THE CAP. MOST LIKELY AREAS TO EXPERIENCE THESE CONDITIONS...LEADING TO SURFACE-BASED TSTM INITIATION...APPEAR TO BE NEAR THE LEADING SURFACE LOW OVER NERN ND...AND NEAR TRIPLE POINT LOW MOVING TOWARD NCNTRL NEB DURING THE EVENING. STORMS DEVELOPING NEAR THESE FEATURES WILL ENCOUNTER SUFFICIENT SHEAR AND INSTABILITY FOR ORGANIZATION/PERSISTENCE WITH VERY LARGE HAIL/HIGH WINDS...AND PERHAPS AN ISOLATED TORNADO OR TWO. LATEST DETERMINISTIC AND ENSEMBLE GUIDANCE SUGGESTS THAT GREATER STORM COVERAGE IS MORE LIKELY TO OCCUR ON THE COOLER/DRIER SIDE OF THE FRONTAL ZONE...FROM NERN CO/WRN NEB ACROSS CNTRL SD THROUGH THE LATE NIGHT. THIS SCENARIO APPEARS REALISTIC GIVEN STRONGER HEIGHT FALLS TO THE WEST OF THE DEEP LAYER BAROCLINIC ZONE... MERIDIONAL CONFIGURATION OF THE LARGER SCALE SYSTEM...AND STRENGTH OF THE CAP. EVEN THOUGH THIS POST-FRONTAL ACTIVITY MAY BE ROOTED ABOVE A MORE STABLE BOUNDARY LAYER...EXTREME SHEAR...STRONG FORCING...AND STEEP LAPSE RATES SHOULD RESULT IN NUMEROUS INTENSE STORMS/SUPERCELLS WITH LARGE HAIL POTENTIAL. AS THIS CONVECTION EVOLVES INTO AN MCS AND SPREADS NEWD ACROSS NEB/SD THROUGH LATE TONIGHT...OUTFLOW REINFORCED FRONTAL SURGE MAY PROVE SUFFICIENT TO PROMOTE ADDITIONAL HIGH-BASED TSTMS...WITH SOME WIND AND HAIL THREAT SPREADING EAST TO ERN NEB AND WRN MN THROUGH EARLY MONDAY. ...DRYLINE FROM SRN NEB TO WEST TX... STRONG HEATING/MIXING WILL AGAIN PRODUCE POCKETS OF MESOSCALE FORCING SUFFICIENT FOR ISOLATED HIGH-BASED TSTM DEVELOPMENT BY LATE AFTERNOON THESE AREAS. UNLIKE SATURDAY AFTERNOON...GRADUAL HEIGHT RISES AND GENERALLY WEAKER MID LEVEL FLOW/SHEAR MAY TEND TO LIMIT OVERALL STORM COVERAGE/INTENSITY AND ONLY A LOW PROBABILITY WIND/HAIL THREAT APPEARS WARRANTED FOR THE DRYLINE TODAY. ...TX/LA GULF COAST TO LOWER MS VALLEY... WEAK IMPULSE/MCV CURRENTLY TRACKING EWD ACROSS SOUTH TX COULD ENHANCE TSTM POTENTIAL IN VERY MOIST UNSTABLE GULF COAST AIR MASS. STRONG INFLUX OF GULF MOISTURE AROUND SWRN FLANK OF EAST COAST ANTICYCLONE WILL FUEL A FEW INTENSE STORM CLUSTERS SPREADING INLAND SIMILAR TO SATURDAY ACROSS LA. A COUPLE OF HAIL EVENTS AND A FEW WET MICRO BURSTS APPEAR POSSIBLE. ....FL/AL/GA... RESIDUAL FRONT SITUATED ACROSS AL/GA BORDER MAY AGAIN PROVIDE A FOCUS FOR AFTERNOON STORMS IN VERY UNSTABLE AND WEAKLY CAPPED ENVIRONMENT. ADDITIONALLY...STRONG INSTABILITY AND SEA/GULF BREEZE COLLISION ACROSS FL WILL RESULT IN NUMEROUS STRONG STORMS OVER THE PENINSULA. DESPITE LIMITED SHEAR...STORM MERGERS AND BOUNDARY INTERACTIONS IN VERY MOIST AND UNSTABLE REGIME SHOULD RESULT IN A FEW SEVERE WIND/HAIL EVENTS. ..CARBIN/GUYER.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 13:05:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 09:05:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281304 SWODY1 SPC AC 281302 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0802 AM CDT SUN MAY 28 2006 VALID 281300Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN HIGH PLAINS... ...SYNOPSIS... WATER VAPOR IMAGERY SUGGESTS JET STREAK IS MOVING INTO BASE OF THE DEEP UPPER TROUGH OVER THE WRN STATES...SUGGESTING SYSTEM HAS REACHED MAXIMUM AMPLITUDE. AS JET STREAK BEGINS TO MOVE NEWD ON EAST SIDE OF TROUGH...TROUGH WILL ALSO LIFT NEWD ACROSS NRN ROCKIES TODAY AND INTO CANADA TONIGHT AS DOWNSTREAM RIDGE BUILDS OVER ERN STATES. AT THE SURFACE...NORTHEAST/SOUTHWEST QUASI-STATIONARY FRONT FROM SERN MANITOBA INTO LOW OVER EXTREME NRN SD...THEN CONTINUES SWWD INTO SECOND LOW OVER NERN CO. A COLD FRONT TRAILS SWWD FROM THE CO LOW INTO FOUR-CORNERS REGION AND NWRN AZ. THE SD LOW IS EXPECTED TO LIFT NEWD ALONG THE FRONT TOWARD NERN ND THIS AFTERNOON AND INTO SERN MANITOBA TONIGHT. THE CO LOW IS FORECAST TO MOVE LITTLE TODAY BEFORE LIFTING NEWD AND WEAKENING TONIGHT AS COLD FRONT BEGINS TO MOVE EWD ACROSS THE NRN AND CENTRAL PLAINS...REACHING A NRN MN/ERN NEB/SERN CO LINE BY 29/12Z. A NORTH/SOUTH DRY LINE EXTENDING FROM WRN NEB AND KS INTO SERN NM AND THE TRANSPECOS REGION OF TX IS EXPECTED TO MIX EWD THIS AFTERNOON. IN THE EAST...WEAK COLD FRONT EXTENDS FROM THE GA COAST NWWD INTO NRN AL...CONTINUING NWWD AS A QUASI-STATIONARY FRONT ACROSS IND...THEN AS A WARM FRONT INTO NRN MN. SERN PART OF THE FRONT WILL MOVE SWD INTO THE FL PENINSULA TODAY. ...NRN PLAINS/NRN MN... ELEVATED THUNDERSTORMS HAVE DEVELOPED OVER EXTREME NRN MN NORTH OF THE SURFACE WARM FRONT WITHIN THAT LAST HOUR. 12Z INL SOUNDING EXHIBITS STRONG INSTABILITY ABOVE COOL SURFACE-BASED LAYER...WITH MODEST EFFECTIVE SHEAR. PRIMARY THREAT WILL BE LARGE HAIL OVER PARTS OF KOOCHICHING...NRN ST LOUIS...AND POSSIBLY LAKE AND COOK COUNTIES DURING THE NEXT 2 HOURS...AFTER WHICH ACTIVITY SHOULD MOVE INTO ONTARIO. AMPLE LOW LEVEL MOISTURE /SURFACE DEW POINTS IN THE MID/UPPER 60S/IN THE WARM SECTOR COUPLED WITH STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH ELEVATED MIXED LAYER WILL CONTRIBUTE TO STRONG INSTABILITY THIS AFTERNOON WITH MLCAPE REACHING 2500-3500 J/KG. 12Z SOUNDINGS SHOW A STRONG CAP JUST ABOVE 850 MB...AND THIS IS LIKELY TO REMAIN IN PLACE INTO THE AFTERNOON INHIBITING DEVELOPMENT OF SURFACE-BASED CONVECTION EAST OF THE FRONT. MODEL GUIDANCE INDICATES INITIAL STORMS THIS AFTERNOON WILL BE ELEVATED WEST OF SURFACE FRONT OVER NORTH CENTRAL CO/ERN WY/NEB PANHANDLE AND WRN SD...FORMING IN RESPONSE TO DYNAMIC FORCING ASSOCIATED WITH MID/UPPER LEVEL JET STREAK LIFTING NNEWD FROM THE CENTRAL TOWARD THE NRN HIGH PLAINS. THIS CONVECTION IS LIKELY TO SPREAD NEWD WEST OF THE FRONT INTO PARTS OF THE DAKOTAS DURING THE EVENING...WHILE POTENTIAL EXISTS FOR ADDITIONAL STORMS TO DEVELOP ALONG THE FRONT FROM ERN SD INTO EXTREME ERN ND/NWRN MN. STRONGEST DEEP LAYER SHEAR WILL BE LOCATED WEST OF THE FRONT AND WILL SUPPORT ELEVATED SUPERCELLS IN THAT REGION. ALTHOUGH SHEAR DIMINISHES WITH EWD EXTENT INTO THE WARM SECTOR IT SHOULD BE SUFFICIENT TO ENHANCE ORGANIZED SEVERE STORM THREAT WITH ANY SURFACE-BASED STORMS ALONG THE FRONT. LARGE HAIL IS EXPECTED TO BE THE PRIMARY THREAT ALONG WITH DAMAGING WIND GUSTS. ACTIVITY IS EXPECTED TO CONTINUE NEWD INTO THE OVERNIGHT HOURS. ...CENTRAL/SRN HIGH PLAINS... UNSTABLE AIR MASS WILL EXTEND ALG/EAST OF THE DRY LINE AS MOISTURE RETURNS WWD IN THE WAKE OF MORNING CONVECTION OVER PARTS OF SRN OK AND CENTRAL TX. ALTHOUGH LARGE SCALE ASCENT WILL BE MINIMAL AS UPPER TROUGH LIFTS NEWD AWAY FROM THE REGION...COMBINATION OF STRONG HEATING AND WEAK CONVERGENCE ALONG THE DRYLINE MAY BE SUFFICIENT TO WEAKEN CAP AND PERMIT DEVELOPMENT OF A FEW THUNDERSTORMS DURING THE LATE AFTERNOON AND EVENING. VERY STEEP LAPSE RATES WILL ENHANCE UPWARD ACCELERATION FOR ANY PARCELS THAT REACH THE LFC...AND DEEP WELL-MIXED BOUNDARY LAYER WILL SUPPORT STRONG DOWNDRAFTS SUGGESTING THREAT FOR LARGE HAIL AND STRONG WIND GUSTS. SREF ETA-KF MEMBERS AND 06Z ETA SUGGEST MOST LIKELY REGION FOR CONVECTIVE DEVELOPMENT WILL BE ALONG GAG-SJT AXIS...AND SLIGHT RISK HAS BEEN ADDED TO THAT REGION. ...CENTRAL/ERN TX AND SERN OK INTO SWRN AR AND LA... ANIMATED RADAR IMAGERY OF CONVECTIVE SYSTEMS DURING THE PRE-DAWN HOURS INDICATED THE PRESENCE OF MCV/S OVER CENTRAL TX AND EXTREME NRN TX NEAR THE RED RIVER EAST OF SPS. IF THESE SYSTEMS MAINTAIN ORGANIZATION AND CONTINUE EWD TODAY...THEY MAY INCREASE THUNDERSTORM DEVELOPMENT FROM CENTRAL/ERN TX AND SERN OK EWD INTO SWRN AR AND LA. PRESENCE OF MODERATELY UNSTABLE PRE-CONVECTIVE ENVIRONMENT WITH MLCAPE OF 2000-3000 J/KG AND DYNAMICALLY ENHANCED MID LEVEL WINDS/ASSOCIATED VERTICAL SHEAR SUGGESTS POTENTIAL FOR ISOLATED SEVERE STORMS THIS AFTERNOON AND EVENING. ...PARTS OF AL/GA/FL... COLD FRONT SAGGING SWD/SWWD ACROSS PARTS OF GA INTO AL AND FL IS EXPECTED TO PROVIDE FOCUS FOR THUNDERSTORM DEVELOPMENT TODAY. 12Z REGIONAL SOUNDINGS SUGGEST MLCAPE WILL INCREASE TO 2000-2500 J/KG AS STRONG INSOLATION OCCURS. WEAK VERTICAL SHEAR COUPLED WITH DRY AIR AVAILABILITY AND STEEP LOW LEVEL LAPSE RATES SUGGEST POTENTIAL FOR PULSE STORMS WITH MARGINAL HAIL AND ISOLATED WET MICROBURSTS. ..WEISS/GUYER.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 16:35:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 12:35:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281629 SWODY1 SPC AC 281628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT SUN MAY 28 2006 VALID 281630Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF WESTERN OK AND TX... WATER VAPOR LOOPS SHOW STRONG UPPER TROUGH ROTATING EASTWARD ACROSS UT. THIS FEATURE WILL SURGE INTO CO/WY THIS EVENING...AND INTO THE NORTHERN HIGH PLAINS BY MONDAY MORNING. STRONG SOUTHERLY LOW LEVEL WINDS AHEAD OF SYSTEM WILL MAINTAIN AMPLE MOISTURE IN WARM SECTOR OF SURFACE LOW MOVING FROM CO INTO WESTERN MN DURING THE PERIOD. HOWEVER...VERY WARM 700MB TEMPERATURES SHOULD EFFECTIVELY CAP THE WARM SECTOR. THIS WILL FOCUS GREATEST THREAT OF DEEP CONVECTION TO THE NORTH/WEST OF SURFACE LOW AND WARM FRONT...AND IN THE HIGH PLAINS WHERE STRONG HEATING AND DEEP MIXING WILL AID CONVECTIVE INITIATION. ...NORTHERN ND/MN... SCATTERED THUNDERSTORMS CONTINUE TO FORM THIS MORNING IN LOW/MID LEVEL WARM ADVECTION ZONE ACROSS NORTHERN ND AND NORTHERN MN...INTO SOUTHERN MANITOBA/NORTHWEST ONTARIO. RICH LOW LEVEL MOISTURE HAS BECOME ESTABLISHED FROM CENTRAL ND INTO MN WITH DEWPOINTS NEAR 70F. INCREASING CAPPING INVERSION OVER THIS REGION WILL LIMIT AREAL COVERAGE OF STORMS. HOWEVER...STRONG HEATING WITH AFTERNOON TEMPS NEAR 90F WILL RESULT IN MLCAPE VALUES OVER 4000 J/KG. LOW AND MID LEVEL WIND FIELDS WILL NOT BE VERY STRONG...BUT SOME VEERING WITH HEIGHT AND REMNANT BOUNDARIES MAY PROMOTE SUPERCELL DEVELOPMENT AND THREAT OF LARGE HAIL AND DAMAGING WINDS. ISOLATED TORNADOES CANNOT BE RULED OUT THIS AFTERNOON AND EVENING. ...WY/NEB/SD/ND/MN... STRONG DAYTIME HEATING WILL OCCUR THIS AFTERNOON ACROSS EASTERN WY AND WESTERN SD/NEB...RESULTING IN NEAR DRY-ADIABATIC LOW/MID LEVEL LAPSE RATES AND DEEP MIXING. THIS SHOULD AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER THIS REGION...WEST OF PRIMARY MOISTURE GRADIENT. THESE HIGH-BASED STORMS MAY PRODUCE LOCALLY GUSTY WINDS AND HAIL. ACTIVITY IS EXPECTED TO INTERACT WITH RICHER MOISTURE PLUME BY EARLY EVENING ACROSS WESTERN SD/NEB...WHERE FURTHER INTENSIFICATION IS EXPECTED. THESE STORMS ARE LIKELY TO SPREAD NORTHEASTWARD TOWARD SOUTHEAST ND AND WESTERN MN OVERNIGHT. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE IN STRONGER CELLS. ...WEST TX/OK... ANOTHER DAY OF FULL SUNSHINE AND DEEP MIXING WILL OCCUR TODAY ALONG THE DIFFUSE DRYLINE OVER WEST TX AND WESTERN OK. ISOLATED THUNDERSTORM DEVELOPMENT APPEARS POSSIBLE ALONG THIS AXIS...ALTHOUGH DRIER AIR ON WATER VAPOR IMAGERY AND SLIGHTLY WEAKER FORECAST SHEAR PROFILES SUGGEST LESS COVERAGE AND INTENSITY THAN YESTERDAY. HIGH-BASED STORMS CAPABLE OF GUSTY WINDS AND HAIL ARE THE MAIN THREAT. ...SOUTHEAST TX/SOUTHWEST LA... LARGE CLUSTER OF THUNDERSTORMS IS ONGOING THIS MORNING OVER THE MIDDLE TX GULF COAST. THESE STORMS MAY PERSIST FOR SEVERAL MORE HOURS...ALONG WITH THE THREAT OF EASTWARD DEVELOPMENT ALONG COAST. HIGH CAPE VALUES AND WEAK VERTICAL SHEAR SUGGEST THAT PULSE-TYPE SEVERE STORMS ARE MOST LIKELY...WITH LOCALLY GUSTY WINDS. ...GA/FL... UPPER RIDGE AXIS EXTENDS FROM EASTERN AL ALONG THE FL PENINSULA TODAY. AIR MASS UNDER RIDGE IS VERY MOIST/UNSTABLE WITH DEWPOINTS NEAR 70F AND AFTERNOON MLCAPE VALUES AROUND 2000 J/KG. WEAK WINDS ALOFT WILL LIMIT CONVECTIVE ORGANIZATION WITH PULSE-TYPE STORMS MOST LIKELY. HOWEVER...SEA-BREEZE INTERACTIONS AND REMNANT WEAK COLD FRONT MAY HELP FOCUS ACTIVITY WITH THE POTENTIAL FOR WET-MICROBURSTS AND HAIL IN STRONGEST CELLS. ..HART/LEVIT.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 20:01:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 16:01:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281958 SWODY1 SPC AC 281957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT SUN MAY 28 2006 VALID 282000Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER SRN GA AND PARTS OF NRN/CNTRL FL... ...NRN PLAINS... 19Z SFC ANALYSIS PLACES A 995 LOW NCNTRL ND WITH A COLD FRONT EXTENDING S THROUGH CNTRL SD...THEN WWD ACROSS NCNTRL NEB INTO NERN CO. OUTFLOW FROM MANT/NWRN ONT MCS HAS STALLED FROM NEAR KINL WWD TO JUST N OF KRDR THEN TO THE LOW. THOUGH THE AIR MASS WAS BEGINNING TO RECOVER ALONG THE INTERNATIONAL BORDER...VERY WARM H8-H7 TEMPERATURES CONTINUES TO CAP A HOT AND MOIST BOUNDARY LAYER ACROSS THE PLAINS. LATEST RUC/ACARS SHOWS +14 DEGREE C H7 TEMPERATURES SURGING INTO SRN MANT/NWRN ONT THROUGH LATE AFTN. THUS...PROSPECTS FOR SFC-BASED STORM INITIATION ARE NOT HIGH...BUT NOT ENTIRELY OUT OF THE QUESTION...ALONG THE OUTFLOW BOUNDARY OR COLD FRONT THROUGH THE AFTN IN THE U.S. THUS...HAVE MAINTAINED CONDITIONAL LOW PROBABILITIES FOR TORNADOES AND/OR LARGE HAIL-DAMAGING WINDS OVER FAR NERN ND AND NWRN MN. UPSTREAM...BOUNDARY LAYER FLOW WAS BEGINNING TO TURN UPSLOPE ACROSS SWRN SD...NEB AND WY...OWING TO WY CYCLOGENESIS AND DIURNAL AFFECTS. WATER VAPOR SHOWS EVIDENCE OF A WEAK SPEED MAX MOVING NWD THROUGH THE CNTRL ROCKIES. AS WEAK HEIGHT FALLS/WEAK COOLING ALOFT SPREAD NEWD ACROSS THE HIGH PLAINS...TSTMS ARE EXPECTED TO INCREASE OVER THE HIGHER TERRAIN OF SD AND WY LATER THIS AFTN. THESE STORMS WILL PROBABLY DEVELOP ENEWD ALONG/N OF THE COLD FRONT INTO NWRN NEB AND SD OVERNIGHT. EFFECTIVE SHEAR IMPROVES WEST OF THE FRONT AND SUPERCELLS WILL BE POSSIBLE WITH LARGE HAIL ALONG THE HIGHER PLAINS. IT IS NOT CLEAR HOW OVERNIGHT ACTIVITY WILL EVOLVE...BUT IT IS REASONABLE TO EXPECT A LOOSELY ORGANIZED MCS TO LIFT ENEWD ACROSS PARTS OF THE DAKS WITH RISKS OF DAMAGING WINDS...HAIL AND PERHAPS AN ISOLD TORNADO. ..SRN HIGH PLAINS... SATL SHOWS SMALL CU DEVELOPING VCNTY THE CAPROCK WHERE BOUNDARY LAYER HAS BECOME HOT AND SFC DEW POINTS HAVE REMAINED 52-61 DEGREE F. PRIND HIGH-BASED TSTMS WILL DEVELOP ALONG THE CAPROCK AFT 22Z AND COULD BRIEFLY BECOME SUPERCELLULAR. COVERAGE WILL BE LESS THAN YESTERDAY...BUT GIVEN MAGNITUDE OF LAPSE RATES...LARGE HAIL AND DAMAGING WINDS WILL BE LIKELY. ACTIVITY SHOULD DIMINISH DURING THE EVENING. ...DEEP S TX... COLD POOL FROM NIGHTTIME SCNTRL TX MCS HAS GONE STATIONARY NW-SE ACROSS DEEP S TX. TSTMS CONTINUE TO FORM ALONG THIS BOUNDARY WHERE CINH HAS ERODED OWING TO STRONG HEATING/MOISTENING AND CIRCULATION INVOF THE COLD POOL. STORM MERGERS WILL BRIEFLY ENHANCE UPDRAFTS AND STORMS COULD GIVE LOCAL DAMAGING WINDS AND HAIL. ...MID-SOUTH TO FL... UPPER RIDGE AXIS EXTENDS FROM EASTERN AL ALONG THE FL PENINSULA TODAY. AIR MASS UNDER RIDGE IS VERY MOIST/UNSTABLE WITH DEWPOINTS NEAR 70F AND AFTERNOON MLCAPE VALUES AROUND 2000 J/KG. WEAK WINDS ALOFT WILL LIMIT CONVECTIVE ORGANIZATION WITH PULSE-TYPE STORMS MOST LIKELY. HOWEVER...SEA-BREEZE INTERACTIONS AND REMNANT WEAK COLDFRONT MAY HELP FOCUS ACTIVITY WITH THE POTENTIAL FOR WET MICROBURSTS AND HAIL IN STRONGEST CELLS. ..RACY.. 05/28/2006  From swody1 at goshenarc.org Mon May 29 01:04:17 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 21:04:17 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290102 SWODY1 SPC AC 290100 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0800 PM CDT SUN MAY 28 2006 VALID 290100Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF WEST TX AND WRN OK... ...NRN PLAINS... LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW SSWLY FLOW ACROSS THE HIGH PLAINS WITH A SHORTWAVE TROUGH EMBEDDED IN THE FLOW OVER NERN CO AND SERN WY. AN MCS IS DEVELOPING AHEAD OF THIS FEATURE AND WILL LIKELY CONTINUE NEWD ACROSS WRN AND CNTRL SD THIS EVENING. ALTHOUGH THE MAIN AXIS OF INSTABILITY IS LOCATED WELL EAST OF THE EXPECTED TRACK OF THE MCS...THE STORM COMPLEX SHOULD MOVE INTO INCREASING INSTABILITY HELPING TO SUSTAIN THE CONVECTIVE SYSTEM THROUGH THE OVERNIGHT PERIOD POSSIBLY REACHING ERN ND AND NWRN MN LATE TONIGHT. ALTHOUGH THE MCS IS CURRENTLY IN AN AREA OF WEAK INSTABILITY...THE STRONG VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS IN WRN SD SUGGEST SUPERCELLS WILL BE POSSIBLE. AS THE STORMS MOVE INTO INCREASING INSTABILITY...THE SUPERCELL THREAT MAY INCREASE CONTINUING OVERNIGHT. IN ADDITION...OBJECTIVE ANALYSIS SHOWS A PLUME OF VERY STEEP LAPSE RATES EXTENDING NEWD ACROSS WRN NEB INTO ERN SD. THIS COMBINED WITH STEEP LOW-LEVEL LAPSE RATES SUGGESTS A THREAT FOR LARGE HAIL AND WIND DAMAGE WILL BE ILKLEY WITH THE STRONGER SUPERCELLS AND/OR BOW ECHOES. AN ISOLATED TORNADO THREAT WILL ALSO LIKELY EXIST AS LOW-LEVEL SHEAR PROFILES BECOME MORE FAVORABLE DUE TO A 60 KT LOW-LEVEL JET EXPANDING NWD INTO CNTRL SD LATE THIS EVENING. ...WEST TX AND WRN OK... LATEST WATER VAPOR IMAGERY SHOWS SWLY FLOW IN PLACE ACROSS THE SRN PLAINS. AT THE SFC...A DRYLINE IS LOCATED FROM WRN KS EXTENDING SWD THROUGH THE CNTRL TX PANHANDLE INTO WEST TX ALONG THE ERN EDGE OF THE CAPROCK. SFC DEWPOINTS EAST OF THE DRYLINE ARE IN THE UPPER 50S TO NEAR 60 F WHERE AN AXIS OF MODERATE INSTABILITY IS LOCATED. ISOLATED SEVERE THUNDERSTORMS ARE ONGOING ALONG THE INSTABILITY GRADIENT. CURRENT STORM INTENSITY SHOULD PERSIST THROUGH MOST OF THE EVENING AS SEVERAL MCS CLUSTERS DEVELOP AND MOVE EWD INTO INCREASING INSTABILITY. THE JAYTON TX PROFILER CURRENTLY SHOWS 0-6 KM SHEAR VALUES OF 35-40 KT SUGGESTING THE SUPERCELL THREAT WILL CONTINUE. STEEP LAPSE RATES FROM THE SFC TO MID-LEVELS EXCEED 8.0 C/KM AND THIS SHOULD ENHANCE THE POTENTIAL FOR LARGE HAIL AND ISOLATED WIND DAMAGE POTENTIAL WITH THE STRONGER STORMS. ..BROYLES.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 06:04:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 02:04:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290603 SWODY1 SPC AC 290601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT MON MAY 29 2006 VALID 291200Z - 301200Z ...NO SVR TSTM AREAS FORECAST... ...UPPER MIDWEST/CNTRL AND SRN PLAINS... A SOUTHWEST FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE CNTRL U.S. AS AN UPPER-LEVEL TROUGH MOVES NEWD ACROSS THE NRN PLAINS TODAY. AT THE SFC...A COLD FRONT WILL EXTEND SSWWD FROM CNTRL MN TO CNTRL KS WITH DEWPOINTS EAST OF THE FRONT IN THE MID TO UPPER 60S F. AS SFC TEMPS WARM DURING THE DAY...A MODERATELY TO STRONGLY UNSTABLE UNCAPPED AIRMASS SHOULD BE IN PLACE ALONG AND EAST OF THE FRONTAL ZONE. STORMS SHOULD INITIATE ALONG THE BOUNDARY FIRST IN MN WHERE STRONGER LARGE-SCALE ASCENT IS FORECAST ASSOCIATED WITH THE NRN PLAINS UPPER-TROUGH. AS STORM COVERAGE INCREASES IN THE LATE AFTERNOON...THUNDERSTORM DEVELOPMENT SHOULD OCCUR SWD FROM CNTRL IA ACROSS ERN NEB...NW MO INTO KS AND POSSIBLY NW OK. FORECAST SOUNDINGS THIS AFTERNOON ACROSS THE UPPER MIDWEST SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ACROSS MN AND NRN IA SUGGESTING SUPERCELLS WILL BE LIKELY IN THE AFTERNOON. THE INSTABILITY AND RELATIVELY COOLER AIR ALOFT SHOULD BE FAVORABLE FOR LARGE HAIL WITH THE STRONGER SUPERCELLS. A WIND DAMAGE THREAT WILL ALSO BE LIKELY AND MAY BECOME ENHANCED AS STORM COVERAGE INCREASES AND CELLS MERGE IN THE LATE AFTERNOON. MCS DEVELOPMENT APPEARS LIKELY BY EARLY EVENING AS A LINE OF STORMS WITH LARGE HAIL AND WIND DAMAGE POTENTIAL MOVES EWD INTO WRN WI. FURTHER SOUTH ACROSS THE SRN AND CNTRL PLAINS...STRONG INSTABILITY SHOULD BE PRESENT BY LATE AFTERNOON WITH MLCAPE VALUES ABOVE 3000 J/KG FORECAST ALONG AND AHEAD OF THE BOUNDARY. IN ADDITION...AFTERNOON FORECAST SOUNDINGS SHOW MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. A FEW SUPERCELLS MAY HAVE VERY LARGE HAIL ESPECIALLY WITH STORMS THAT HAVE ACCESS TO LOCALLY STRONG TO EXTREME INSTABILITY. WIND DAMAGE WILL ALSO BE POSSIBLE WITH THE STRONGER STORMS AND MAY CONTINUE OVERNIGHT WITH ANY MCS THAT DEVELOPS AND TRACKS EWD ACROSS THE REGION. ...SRN NEW ENGLAND/MID-ATLANTIC.... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN U.S. TODAY AS A SHORTWAVE TROUGH TOPS THE RIDGE AND MOVES ACROSS NEW ENGLAND. IN RESPONSE...THUNDERSTORM DEVELOPMENT SHOULD OCCUR AHEAD OF THE SHORTWAVE IN THE NRN APPALACHIAN MTNS AND SPREAD SEWD ACROSS SRN NEW ENGLAND INTO THE MID-ATLANTIC STATES IN THE AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW SFC DEWPOINTS IN THE 60S F WHICH SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY. IN ADDITION...0-6 KM SHEAR VALUES ARE FORECAST TO BE THE 30-35 KT RANGE SUGGESTING SUPERCELLS WILL BE POSSIBLE NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. HAIL AND ISOLATED WIND DAMAGE WOULD BE THE MAIN THREAT WITH ANY SUPERCELLS THAT DEVELOP IN THE MID TO LATE AFTERNOON. ..BROYLES/GUYER.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 06:18:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 02:18:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290616 SWODY1 SPC AC 290614 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0114 AM CDT MON MAY 29 2006 VALID 291200Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST...CNTRL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SRN NEW ENGLAND AND THE MID-ATLANTIC STATES... CORRECTED CATEGORICAL OUTLOOK GRAPHIC ...UPPER MIDWEST/CNTRL AND SRN PLAINS... A SOUTHWEST FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE CNTRL U.S. AS AN UPPER-LEVEL TROUGH MOVES NEWD ACROSS THE NRN PLAINS TODAY. AT THE SFC...A COLD FRONT WILL EXTEND SSWWD FROM CNTRL MN TO CNTRL KS WITH DEWPOINTS EAST OF THE FRONT IN THE MID TO UPPER 60S F. AS SFC TEMPS WARM DURING THE DAY...A MODERATELY TO STRONGLY UNSTABLE UNCAPPED AIRMASS SHOULD BE IN PLACE ALONG AND EAST OF THE FRONTAL ZONE. STORMS SHOULD INITIATE ALONG THE BOUNDARY FIRST IN MN WHERE STRONGER LARGE-SCALE ASCENT IS FORECAST ASSOCIATED WITH THE NRN PLAINS UPPER-TROUGH. AS STORM COVERAGE INCREASES IN THE LATE AFTERNOON...THUNDERSTORM DEVELOPMENT SHOULD OCCUR SWD FROM CNTRL IA ACROSS ERN NEB...NW MO INTO KS AND POSSIBLY NW OK. FORECAST SOUNDINGS THIS AFTERNOON ACROSS THE UPPER MIDWEST SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ACROSS MN AND NRN IA SUGGESTING SUPERCELLS WILL BE LIKELY IN THE AFTERNOON. THE INSTABILITY AND RELATIVELY COOLER AIR ALOFT SHOULD BE FAVORABLE FOR LARGE HAIL WITH THE STRONGER SUPERCELLS. A WIND DAMAGE THREAT WILL ALSO BE LIKELY AND MAY BECOME ENHANCED AS STORM COVERAGE INCREASES AND CELLS MERGE IN THE LATE AFTERNOON. MCS DEVELOPMENT APPEARS LIKELY BY EARLY EVENING AS A LINE OF STORMS WITH LARGE HAIL AND WIND DAMAGE POTENTIAL MOVES EWD INTO WRN WI. FURTHER SOUTH ACROSS THE SRN AND CNTRL PLAINS...STRONG INSTABILITY SHOULD BE PRESENT BY LATE AFTERNOON WITH MLCAPE VALUES ABOVE 3000 J/KG FORECAST ALONG AND AHEAD OF THE BOUNDARY. IN ADDITION...AFTERNOON FORECAST SOUNDINGS SHOW MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. A FEW SUPERCELLS MAY HAVE VERY LARGE HAIL ESPECIALLY WITH STORMS THAT HAVE ACCESS TO LOCALLY STRONG TO EXTREME INSTABILITY. WIND DAMAGE WILL ALSO BE POSSIBLE WITH THE STRONGER STORMS AND MAY CONTINUE OVERNIGHT WITH ANY MCS THAT DEVELOPS AND TRACKS EWD ACROSS THE REGION. ...SRN NEW ENGLAND/MID-ATLANTIC.... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN U.S. TODAY AS A SHORTWAVE TROUGH TOPS THE RIDGE AND MOVES ACROSS NEW ENGLAND. IN RESPONSE...THUNDERSTORM DEVELOPMENT SHOULD OCCUR AHEAD OF THE SHORTWAVE IN THE NRN APPALACHIAN MTNS AND SPREAD SEWD ACROSS SRN NEW ENGLAND INTO THE MID-ATLANTIC STATES IN THE AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW SFC DEWPOINTS IN THE 60S F WHICH SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY. IN ADDITION...0-6 KM SHEAR VALUES ARE FORECAST TO BE THE 30-35 KT RANGE SUGGESTING SUPERCELLS WILL BE POSSIBLE NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. HAIL AND ISOLATED WIND DAMAGE WOULD BE THE MAIN THREAT WITH ANY SUPERCELLS THAT DEVELOP IN THE MID TO LATE AFTERNOON. ..BROYLES.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 13:02:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 09:02:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291301 SWODY1 SPC AC 291259 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 AM CDT MON MAY 29 2006 VALID 291300Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM THE UPPER MS VALLEY INTO THE CENTRAL PLAINS... ...SYNOPSIS... MAIN PATTERN IS MID/UPPER LEVEL TROUGH OVER THE WEST WITH RIDGING OVER THE ERN THIRD OF THE U.S. SURFACE FRONTAL BOUNDARY EXTENDED FROM NWRN MN SSWWD ACROSS SERN SD INTO SWRN KS AND THE OK PANHANDLE. ...CENTRAL MN INTO WRN WI..AND SWD INTO IA... MODELS BRING SEVERAL SHORTWAVE TROUGHS AROUND BASE OF WRN U.S. FULL LATITUDE TROUGH NNEWD INTO THE NRN PLAINS/NRN MN. MUCH OF THE FLOW IS UNIDIRECTIONAL...AND WOULD EXPECT LITTLE MOVEMENT EWD OF FRONTAL BOUNDARY INTO EARLY THIS AFTERNOON. NAM/GFS MOVE THE FRONT INTO ERN MN SSWWD INTO EXTREME SERN NEB BY 2100Z. ASSUME MUCH OF THIS WILL BE DUE TO CONVECTION DEVELOPING ON/JUST BEHIND THE BOUNDARY WHERE THERE WILL BE SOME SHEAR. AHEAD OF THE FRONT...AIR MASS IS EXPECTED TO BECOME VERY UNSTABLE DUE TO STRONG DAYTIME HEATING IN THE MIXED LAYER. MLCAPE ARE PROJECTED TO BE 3000-4000 J/KG FROM CENTRAL MN SSWWD INTO PARTS OF IA WITH SFC-3KM LAPSE RATES AROUND 8.0-8.5C/KM MOSTLY DUE TO HEATING. THIS AREA WILL ALSO BE IN FAVORABLE ENTRANCE REGION OF MID/UPPER LEVEL JET STREAK EXTENDING FROM WRN NEB INTO NERN ND BY TONIGHT ENHANCING UVVS ALONG THE BOUNDARY MOVING INTO VERY UNSTABLE AIR MASS. MAIN THREATS THIS AFTERNOON INTO EARLY TONIGHT WILL BE LARGE HAIL AND DAMAGING WINDS SUPPORTED BY STEEP LOW-MID LEVEL LAPSE RATES. ...AREA FROM IA SWWD THRU KS INTO WRN OK AND ERN TX PANHANDLE... NAM MODEL DEVELOPS STRONG SLOW MOVING CONVECTION/MCS LATE THIS AFTERNOON AND TONIGHT AS A WEAK SHORTWAVE TROUGH MOVES NEWD EMBEDDED IN WEAKER MID LEVEL FLOW OVER SERN AZ INTO SERN CO. DEVELOPMENT WILL BE NEAR FRONTAL BOUNDARY/DRYLINE INTERSECTION. SURFACE PROG INDICATES SELY INTO ELY FLOW INTO AREA OF UPSLOPE FLOW AND DEW POINTS POOLING IN THE MID/UPPER 60S WILL RESULT IN THUNDERSTORM/MCS DEVELOPMENT IN VICINITY OF WEAK LOW OVER NWRN OK/TX PANHANDLE WHERE STEEP LOW/MID LEVEL LAPSE RATES WILL BE AROUND 8C/KM AND MLCAPE WILL BE AROUND 3000 J/KG. POSSIBILITY EXISTS FOR LARGE HAIL AND DOWNBURST WINDS THIS EVENING... DECREASING TONIGHT WITH LOSS OF DAYTIME HEATING. ...PARTS NY INTO MA/CT/RI... REMNANTS OF MCV MENTIONED IN MESOSCALE DISCUSSION 1019 ISSUED AT 1008Z CONTINUES TO MOVE SEWD ACROSS NERN NY STATE THIS MORNING. MORNING RAOB DATA FROM BUF SHOWS SOME MID LEVEL INSTABILITY ASSOCIATED WITH MID LEVEL LAPSE RATES NEAR 7C/KM. ACTIVITY WILL MOVE SEWD THROUGH EARLY THIS AFTERNOON PRODUCING MOSTLY STRONG STORMS WITH SOME SMALL HAIL. ..MCCARTHY/GUYER.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 16:20:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 12:20:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291612 SWODY1 SPC AC 291610 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1110 AM CDT MON MAY 29 2006 VALID 291630Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MIDWEST STATES AND CENTRAL PLAINS... LARGE UPPER RIDGE REMAINS OVER THE EASTERN UNITED STATES TODAY...WHILE SERIES OF SHORTWAVE TROUGHS ROTATE AROUND LONGWAVE TROUGH OVER THE WESTERN STATES. MAIN SURFACE BAROCLINIC ZONE HAS SHIFTED EASTWARD INTO PARTS OF MN/IA/NEB/KS TODAY...WHERE POTENTIAL EXISTS FOR SCATTERED THUNDERSTORMS. OTHER ACTIVITY WILL ONCE AGAIN OCCUR ALONG DRYLINE OVER PARTS OF OK/TX. FINALLY...STRONG INSTABILITY AND AMPLE MOISTURE MAY LEAD TO ISOLATED THUNDERSTORMS OVER PARTS OF THE MS/OH/TN VALLEYS AND SOUTHEAST STATES. ...UPPER MIDWEST INTO CENTRAL PLAINS... MORNING SURFACE ANALYSIS SHOWS FRONT EXTENDING FROM WESTERN MN INTO CENTRAL KS AND THE TX PANHANDLE. AIR MASS ALONG AND EAST OF FRONT REMAINS MOIST AND MODERATELY UNSTABLE WITH DEWPOINTS IN THE UPPER 60S AND AFTERNOON MLCAPE VALUES EXPECTED TO EXCEED 3000 J/KG. MORNING SOUNDINGS AND MODEL GUIDANCE SUGGEST THAT CAP HAS WEAKENED SINCE YESTERDAY...WHICH SHOULD ALLOW SCATTERED THUNDERSTORM DEVELOPMENT ALONG THE FRONT THIS AFTERNOON AND EVENING. HOWEVER...MAIN UPPER FORCING AND VERTICAL SHEAR IS WELL WEST OF BOUNDARY EXCEPT OVER MN. SHEAR IS SUFFICIENT FOR SUPERCELLS AND BOWS OVER PARTS OF CENTRAL/NORTHERN MN...WHERE HIGHER SEVERE PROBABILITIES HAVE BEEN MAINTAINED. HOWEVER... ACTIVITY WILL BE RATHER DISORGANIZED FARTHER SOUTH UNLESS UPSCALE ORGANIZATION CAN OCCUR THIS EVENING AS CONVECTIVE CLUSTERS GROW. DEGREE OF INSTABILITY WILL POSE A THREAT OF LARGE HAIL AND DAMAGING WINDS IN STRONGER CELLS. ...OK/TX... SURFACE DRYLINE IS EXPECTED TO BECOME ESTABLISHED THIS AFTERNOON FROM THE EASTERN TX PANHANDLE INTO THE TRANSPECOS AREA. WEAK FLOW ALOFT...COMBINED WITH RELATIVELY STRONG INSTABILITY...WILL ONCE AGAIN RESULT IN ISOLATED STRONG/SEVERE STORMS. HIGH-BASED CELLS WILL BE CAPABLE OF DAMAGING WINDS AND HAIL FOR A FEW HOURS THIS EVENING BEFORE WEAKENING. ...NORTHEAST STATES... WATER VAPOR IMAGERY SHOWS WELL-DEFINED SHORTWAVE TROUGH TRACKING SOUTHEASTWARD ACROSS NY. WEAK FORCING FOR UPWARD VERTICAL MOTION ALONG THE SOUTHERN PERIPHERY OF THIS FEATURE WILL LIKELY AID IN THE DEVELOPMENT OF ISOLATED AFTERNOON THUNDERSTORMS FROM EASTERN NY/PA SOUTHWARD INTO THE DELMARVA REGION. AIR MASS IN THIS REGION IS MODERATELY UNSTABLE WITH MLCAPE VALUES UP TO 1500 J/KG...ALONG WITH SUFFICIENT NORTHERLY FLOW ALOFT FOR SOME CONVECTIVE ORGANIZATION. AREAL COVERAGE OF STRONGER CELLS REMAINS IN QUESTION DUE TO WEAK FORCING...SO WILL MAINTAIN ONLY LOW SEVERE PROBABILITIES AT THIS TIME. ...MID MS AND TN VALLEYS INTO FL... WATER VAPOR IMAGERY SHOWS AXIS OF MID LEVEL MOISTURE EXTENDING FROM PARTS OF IL/IND ACROSS TN/AL INTO SOUTH FL. THIS IS THE SAME AXIS IN WHICH SCATTERED INTENSE STORMS DEVELOPED YESTERDAY. STRONG DAYTIME HEATING IN THIS ZONE...COUPLED WITH DEWPOINTS NEAR 70F MAY AGAIN PROVE SUFFICIENT FOR WEAKLY ORGANIZED MULTICELL STORMS CAPABLE OF WET MICROBURSTS AND HAIL. SEA-BREEZE INTERACTIONS MAY ALSO ENHANCE STORMS OVER THE WESTERN COAST OF THE FL PENINSULA. ..HART/LEVIT.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 20:05:15 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 16:05:15 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292003 SWODY1 SPC AC 292002 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0302 PM CDT MON MAY 29 2006 VALID 292000Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/TX... ...UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/WRN N TX... STRONG/SEVERE THUNDERSTORMS CONTINUE TO INCREASE AHEAD OF COLD FRONT OVER MN ATTM...WHERE VERY UNSTABLE AIRMASS IS INDICATED. THOUGH STRONGEST FLOW ALOFT SHOULD REMAIN ON THE COOL SIDE OF THE BOUNDARY...SHEAR REMAINS SUFFICIENT GIVEN DEGREE OF INSTABILITY FOR ORGANIZED/LOCALLY INTENSE STORMS. THREAT FOR HAIL AND DAMAGING WINDS WILL CONTINUE INTO THIS EVENING WHILE SHIFTING EWD INTO WI AND WRN UPPER MI...AS STORMS REMAIN ORGANIZED IN A QUASI-LINEAR FASHION. FURTHER S ALONG FRONT...WEAKER WIND FIELD EXISTS. HOWEVER...EXPECT SCATTERED STORMS TO DEVELOP SWD ALONG FRONT WITHIN MARGINALLY-UNSTABLE AIRMASS. LOCALLY STRONG/SEVERE STORMS ARE EXPECTED...ALONG WITH THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL. STORMS WILL LIKELY CONTINUE THROUGH MUCH OF THE PERIOD -- PARTICULARLY ACROSS PARTS OF KS/OK AND VICINITY...AS LOW-LEVEL JET DEVELOPS THIS EVENING. OVERALL SEVERE THREAT SHOULD DIMINISH WITH TIME HOWEVER THROUGH THE END OF THE PERIOD. ...PARTS OF SRN NEW ENGLAND INTO NJ/ERN PA... ISOLATED THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THIS REGION WHERE AIRMASS HAS DESTABILIZED -- PARTICULARLY ALONG AND W OF THE HUDSON VALLEY. THOUGH A STRONGER CELL OR TWO COULD PRODUCE LOCALLY GUSTY WINDS OR SMALL HAIL...OVERALL CONVECTIVE THREAT APPEARS TO BE QUITE LOW. ...TN VALLEY INTO THE CENTRAL GULF COAST REGION... DIURNAL/PULSE-TYPE THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND EARLY EVENING ACROSS THIS REGION...BENEATH UPPER HIGH WHERE WEAK FLOW BUT MODERATE INSTABILITY EXISTS. THREAT FOR LOCALLY GUSTY WINDS/HAIL WILL PERSIST WITH STRONGER STORMS...RAPIDLY DIMINISHING THROUGH THE EVENING. ...S FL... THUNDERSTORMS HAVE DEVELOPED ACROSS S FL NEAR SEA BREEZE BOUNDARIES THIS AFTERNOON...IN AIRMASS FEATURING MODERATE INSTABILITY BUT WEAK SHEAR. THOUGH A FEW PULSE-TYPE SEVERE STORMS WILL REMAIN POSSIBLE INTO THIS EVENING...OVERALL THREAT WILL REMAIN LIMITED/TRANSIENT. ..GOSS.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 21:26:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 17:26:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292122 SWODY1 SPC AC 292121 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0421 PM CDT MON MAY 29 2006 VALID 292000Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/TX... CORRECTED TO CHANGE MARGINAL TO MODERATE IN SECOND PARAGRAPH ...UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/WRN N TX... STRONG/SEVERE THUNDERSTORMS CONTINUE TO INCREASE AHEAD OF COLD FRONT OVER MN ATTM...WHERE VERY UNSTABLE AIRMASS IS INDICATED. THOUGH STRONGEST FLOW ALOFT SHOULD REMAIN ON THE COOL SIDE OF THE BOUNDARY...SHEAR REMAINS SUFFICIENT GIVEN DEGREE OF INSTABILITY FOR ORGANIZED/LOCALLY INTENSE STORMS. THREAT FOR HAIL AND DAMAGING WINDS WILL CONTINUE INTO THIS EVENING WHILE SHIFTING EWD INTO WI AND WRN UPPER MI...AS STORMS REMAIN ORGANIZED IN A QUASI-LINEAR FASHION. FURTHER S ALONG FRONT...WEAKER WIND FIELD EXISTS. HOWEVER...EXPECT SCATTERED STORMS TO DEVELOP SWD ALONG FRONT WITHIN MODERATELY-UNSTABLE AIRMASS. LOCALLY STRONG/SEVERE STORMS ARE EXPECTED...ALONG WITH THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL. STORMS WILL LIKELY CONTINUE THROUGH MUCH OF THE PERIOD -- PARTICULARLY ACROSS PARTS OF KS/OK AND VICINITY...AS LOW-LEVEL JET DEVELOPS THIS EVENING. OVERALL SEVERE THREAT SHOULD DIMINISH WITH TIME HOWEVER THROUGH THE END OF THE PERIOD. ...PARTS OF SRN NEW ENGLAND INTO NJ/ERN PA... ISOLATED THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THIS REGION WHERE AIRMASS HAS DESTABILIZED -- PARTICULARLY ALONG AND W OF THE HUDSON VALLEY. THOUGH A STRONGER CELL OR TWO COULD PRODUCE LOCALLY GUSTY WINDS OR SMALL HAIL...OVERALL CONVECTIVE THREAT APPEARS TO BE QUITE LOW. ...TN VALLEY INTO THE CENTRAL GULF COAST REGION... DIURNAL/PULSE-TYPE THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND EARLY EVENING ACROSS THIS REGION...BENEATH UPPER HIGH WHERE WEAK FLOW BUT MODERATE INSTABILITY EXISTS. THREAT FOR LOCALLY GUSTY WINDS/HAIL WILL PERSIST WITH STRONGER STORMS...RAPIDLY DIMINISHING THROUGH THE EVENING. ...S FL... THUNDERSTORMS HAVE DEVELOPED ACROSS S FL NEAR SEA BREEZE BOUNDARIES THIS AFTERNOON...IN AIRMASS FEATURING MODERATE INSTABILITY BUT WEAK SHEAR. THOUGH A FEW PULSE-TYPE SEVERE STORMS WILL REMAIN POSSIBLE INTO THIS EVENING...OVERALL THREAT WILL REMAIN LIMITED/TRANSIENT. ..GOSS.. 05/29/2006  From swody1 at goshenarc.org Tue May 30 01:02:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 21:02:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300100 SWODY1 SPC AC 300059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT MON MAY 29 2006 VALID 300100Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN AND CNTRL PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PART OS NERN IL AND FAR NW IND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SERN AND SCNTRL MO... ...UPPER MIDWEST/CNTRL AND SRN PLAINS... LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-RIDGE IN PLACE ACROSS THE ERN U.S. WITH SOUTHWEST FLOW PRESENT ACROSS THE PLAINS AND UPPER MIDWEST. AT THE SFC...A COLD FRONT IS LOCATED FROM ERN MN EXTENDING SSWWD INTO SERN NEB. SFC DEWPOINTS EAST OF THE BOUNDARY ARE IN THE MID TO UPPER 60S F PRODUCING VERY UNSTABLE AIR WITH MLCAPE VALUES AROUND 2500 J/KG. A LINEAR MCS IS CURRENTLY ONGOING ACROSS NE MN AND NWRN WI AND THE MCS SHOULD CONTINUE EWD ACROSS THE ARROWHEAD OF MN AND INTO NRN/CNTRL WI LATE THIS EVENING. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES WHICH COMBINED WITH THE MODERATE TO STRONG INSTABILITY SHOULD SUSTAIN THE SUPERCELL THREAT WITH THE STRONGER CELLS EMBEDDED IN THE LINE. THE SEVERE THREAT SHOULD REMAIN MORE ISOLATED ACROSS IA AND SE NEB DUE TO WEAKER LOW-LEVEL FLOW IN THAT AREA. FURTHER SOUTH ACROSS THE CNTRL AND SRN PLAINS...A NEARLY STATIONARY FRONT EXISTS FROM CNTRL KS SWWD INTO WEST TX. SCATTERED STORMS ARE ONGOING ALONG AND JUST AHEAD OF THE FRONT AND SHOULD CONTINUE EWD INTO THE STRONG INSTABILITY LATE THIS EVENING. THE GREATEST CONVECTIVE COVERAGE SHOULD BE ACROSS NRN OK AND SRN KS AS THE LOW-LEVEL JET STRENGTHENS. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES ALONG THE BOUNDARY FROM NRN OK TO NRN KS SUGGESTING SUPERCELLS WILL BE LIKELY. IN ADDITION...STEEP MID-LEVEL LAPSE RATES IN PLACE WILL BE FAVORABLE FOR LARGE HAIL WITH WIND DAMAGE ALSO POSSIBLE AS STORMS MERGE AND MCS DEVELOPMENT OCCURS LATE THIS EVENING. ...ERN MO/NERN IL... SEVERAL MCS CLUSTERS ARE CURRENTLY ONGOING ALONG THE WRN EDGE OF AN ERN U.S. UPPER-LEVEL RIDGE IN NRN IL AND ERN MO. THE STORMS COMPLEXES ARE LOCATED IN A MODERATELY UNSTABLE AIRMASS AND SHOULD CONTINUE THROUGH THE LATE EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW RELATIVELY WEAK SHEAR PROFILES IN PLACE...AN AXIS OF STEEP LOW-LEVEL LAPSE RATES EXIST FROM ERN MO EXTENDING NEWD INTO CNTRL IL AS SHOWN ON OBJECTIVE ANALYSIS. THIS COMBINED WITH THE MODERATE INSTABILITY SHOULD BE ENOUGH TO CONTINUE AN ISOLATED SEVERE THREAT ACROSS ERN MO AND NERN IL FOR AT LEAST A FEW MORE HOURS. ..BROYLES.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 05:57:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 01:57:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300555 SWODY1 SPC AC 300554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT TUE MAY 30 2006 VALID 301200Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...CNTRL PLAINS...NRN OZARKS AND LOWER OH VALLEY... ...TX PANHANDLE/WEST TX/WRN OK/SE CO/WRN KS... A WEAK FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE PLAINS TODAY AS A SUBTLE SHORTWAVE TROUGH MOVES NEWD ACROSS THE HIGH PLAINS IN STRONGER FLOW. AT THE SFC...A COLD FRONT SHOULD BE LOCATED ACROSS SERN CO...THE NRN TX PANHANDLE EXTENDING ENEWD INTO SRN KS. SOUTH OF THE FRONT...SFC DEWPOINTS FROM THE UPPER 50S F TO THE UPPER 60S F SHOULD RESULT IN MODERATE TO STRONG INSTABILITY BY AFTERNOON. STORMS SHOULD INITIATE ALONG THE NRN EDGE OF THE INSTABILITY AXIS WITH SEVERAL CONVECTIVE CLUSTERS MOVING SEWD ACROSS SERN CO...THE TX PANHANDLE AND WRN OK. FORECAST SOUNDINGS ACROSS THE REGION LATE THIS AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ALONG THE FRONTAL BOUNDARY WITH 0-6 KM SHEAR VALUES IN THE 35 TO 45 KT RANGE. THIS COMBINED WITH THE INSTABILITY AND STEEP LAPSE RATES IN PLACE SHOULD BE FAVORABLE FOR SUPERCELLS WITH LARGE HAIL AND ISOLATED WIND DAMAGE. LOW-LEVEL SHEAR PROFILES ARE FORECAST TO BACK AND INCREASE IN THE EARLY EVENING FROM THE WEST TX CAPROCK INTO SWRN OK AND MAY RESULT IN AN ISOLATED TORNADO THREAT WITH THE STRONGER SUPERCELLS. ALTHOUGH THE SEVERE THREAT SHOULD GRADUALLY DROP OFF OVERNIGHT...MODEL FORECASTS ARE GENERAL AGREEMENT DRIVING AN MCS SEWD ACROSS THE LOW-ROLLING PLAINS AND ANOTHER MCS ESEWD ACROSS SWRN KS. ...CNTRL PLAINS/NRN OZARKS/LOWER OH VALLEY... A WEAK FLOW PATTERN WILL REMAIN IN PLACE TODAY AS A COLD FRONT MOVES SLOWLY SWD ACROSS ERN KS...THE NRN OZARKS AND SRN GREAT LAKES. SOUTH OF THE BOUNDARY...MODERATE TO STRONG INSTABILITY SHOULD DEVELOP BY AFTERNOON WITH MLCAPE VALUES RANGING FROM 2000-3000 J/KG. SCATTERED THUNDERSTORMS SHOULD DEVELOP ALONG AND AHEAD OF THE BOUNDARY...SPREAD SEWD ACROSS THE REGION IN THE LATE AFTERNOON AND EARLY EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW RELATIVELY WEAK SHEAR PROFILES...THE AMOUNT OF INSTABILITY SUGGESTS THAT PULSE SEVERE STORMS WILL BE LIKELY. WIND DAMAGE AND HAIL WILL BE POSSIBLE WITH THE STRONGER STORMS ESPECIALLY WHERE LOW-LEVEL LAPSE RATES ARE LOCALLY MAXIMIZED. ...WRN NY/WRN PA AND UPPER 0H VALLEY... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN SEABOARD AS A SHORTWAVE TROUGH MOVES ACROSS THE TOP OF THE RIDGE INTO NEW ENGLAND. AT THE SFC...A WARM FRONT SHOULD BE IN PLACE ACROSS ERN NY WITH SFC DEWPOINTS WEST OF THE BOUNDARY IN THE 60S F. THIS SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY BY AFTERNOON WITH SCATTERED THUNDERSTORMS INITIATING IN THE HIGHER TERRAIN. FORECAST SOUNDINGS SHOW WEAK SHEAR PROFILES SUGGESTING STORMS WILL REMAIN PULSE OR MULTICELLULAR IN NATURE. HOWEVER...A MARGINAL THREAT FOR WIND DAMAGE AND HAIL WILL BE POSSIBLE ESPECIALLY NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. ..BROYLES.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 12:45:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 08:45:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301243 SWODY1 SPC AC 301242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT TUE MAY 30 2006 VALID 301300Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS CONTINUES FROM THE CENTRAL/SRN HIGH PLAINS NEWD INTO THE UPPER GREAT LAKES.... ...SYNOPSIS... LATEST WATER VAPOR IMAGERY CONTINUES TO ILLUSTRATE MID/UPPER LEVEL TROUGH OVER THE WRN U.S. ALONG 114W. LAST IN A SERIES OF EMBEDDED MINOR SHORTWAVES LOOK TO BE OVER NRN UT THIS MORNING AND WILL BE LIFTING NEWD TODAY. MODELS INDICATE THAT AS THIS HAPPENS TROUGH WILL BECOME LESS AMPLIFIED AS ERN U.S. RIDGE HOLD ITS POSITION OVER THE ERN OHIO AND TENNESSEE VALLEYS. SURFACE ANALYSIS THIS MORNING HAS BECOME A STATE OF DISARRAY THANKS TO THE NUMEROUS CLUSTERS OF CONVECTION THAT HAVE BEEN OCCURRING FROM WI THROUGH IA/MO INTO KS...OK AND WEST TEXAS. WHAT IS LEFT OF A QUASISTATIONARY FRONT EXTENDS FROM ERN UPPER MI SWWD INTO SERN MN BEFORE THE PLETHORA OF BOUNDARIES EXTEND FROM CENTRAL IA INTO NERN KS INTO THE EDWARDS PLATEAU REGION OF TX. ...PARTS OF ERN WI SWWD INTO ERN KS... WEAKENING FRONTAL BOUNDARY AND THE NUMEROUS CONVECTIVE BOUNDARIES WILL CONTINUE TO BE FOCUS OF CONVECTION AND ITS REDEVELOPMENT THIS AFTERNOON AND EVENING. AIR MASS ACROSS THE SOUTHERN HALF OF THE PLAINS EWD INTO THE MISSISSIPPI AND OHIO VALLEYS REMAIN POTENTIALLY VERY UNSTABLE WITH MUCAPES BETWEEN 2500 AND 4000 J/KG. THUS...AS DAYTIME HEATING TAKES PLACE THROUGH THIS AFTERNOON...STRONG/SEVERE THUNDERSTORMS WILL DEVELOP WITHIN THIS AIR MASS AND NEAR AREAS CLOSE TO THE OLD CONVECTIVE BOUNDARIES. SOME LARGE HAIL AND DOWNBURST WINDS WILL BE THE MAIN THREAT ACROSS THIS LARGE AREA MAINLY THIS AFTERNOON AND EARLY TONIGHT. ...CENTRAL AND SOUTHERN HIGH PLAINS INTO CENTRAL KS... DUE TO THE CONVECTIVE BOUNDARIES AND WRN U.S. TROUGHING...SURFACE WINDS ARE SELY FOR THE MOST PART ACROSS THE SOUTHERN HALF OF THE PLAINS THIS MORNING AIDING IN THE UPSLOPE FLOW THAT HAS LEAD TO CONVECTION OVER PARTS OF ERN CO AND WRN KS. AGAIN THE BOUNDARIES FROM THIS CONVECTION WILL PLAY ROLE IN INITIATION OF NEW CONVECTION THIS EVENING AND TONIGHT AS LOW LEVEL JET COUPLES WITH MOIST BOUNDARY LAYER. SLY LOW LEVEL JET AROUND 30 KT WILL EXTEND THRU THE SRN HIGH PLAINS ENHANCING WAA/LIFT NEAR THE BOUNDARY FORECAST TO BE E-W ACROSS THE CENTRAL TX PANHANDLE. IN ADDITION...NAM MODELS DEPICTS A SHORTWAVE TROUGH THAT WILL ADVANCE EWD TONIGHT AHEAD OF RELAXING WRN U.S. TROUGH. CONTINUED CONVERGENCE NEAR THE BOUNDARY ENHANCED BY UPSLOPE FLOW COMBINED WITH THIS TROUGH WILL LEAD TO DEVELOPMENT OF MCS TONIGHT OVER PARTS OF ERN CO/SWRN KS INTO THE OK/TX PANHANDLES. FORECAST SOUNDINGS SHOW FAVORABLE PROFILES AND LOW LEVEL SHEAR FOR ISOLATED TORNADOES WITH SOME OF THE DEVELOPING STORMS...CLUSTERING INTO THE MCS WITH THE MAIN THREAT BECOMING HAIL AND DAMAGING WINDS INTO EARLY TONIGHT. ...ERN GREAT LAKES INTO PARTS OF NEW ENGLAND... SECOND IN A SERIES OF WEAK SHORTWAVES HAS TURNED ANTICYCLONICALLY AROUND RIDGE THAT EXTENDS NWD THROUGH THE ERN GREAT LAKES. THIS BROUGHT SOME ISOLATED THUNDERSTORMS TO PARTS OF UPSTATE NY OVERNIGHT. ANOTHER SHORTWAVE IS POISED OVER SERN ONTARIO/SWRN QUEBEC AND IS EXPECTED TO MOVE SEWD THROUGH NERN NY STATE INTO NEW HAMPSHIRE LATER TODAY AND TONIGHT. THUNDERSTORMS COULD OCCUR ONCE AGAIN PRODUCING STRONG WINDS AND SOME HAIL. ...CENTRAL AND SRN FL PENINSULA... 06Z RUN OF THE NAM DEPICTED DEVELOPMENT THIS AFTERNOON OF E TO W MOVING SEA BREEZE BOUNDARY ACROSS PARTS OF THE CENTRAL PENINSULA TOWARDS AREAS FROM TPA SWD THRU FMY AND SRQ THIS AFTERNOON. GIVEN THAT SOUNDINGS SHOW LOW LEVEL LAPSE RATES NEAR 9C/KM BEFORE THE BOUNDARY MOVES INTO AREA...SOME OF THESE STORMS COULD PRODUCE SOME STRONG GUSTY WINDS. ..MCCARTHY.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 16:37:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 12:37:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301629 SWODY1 SPC AC 301627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT TUE MAY 30 2006 VALID 301630Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL AND SOUTHERN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE UPPER MS VALLEY... LARGE UPPER RIDGE CONTINUES TO DOMINATE THE WEATHER OVER MUCH OF THE EASTERN HALF OF THE UNITED STATES TODAY...WITH BROAD/FLAT TROUGH OVER THE WEST AND NORTHWEST FLOW OVER NEW ENGLAND. WIDESPREAD MOIST/UNSTABLE AIR SHOULD LEAD TO NUMEROUS SHOWERS AND THUNDERSTORMS TODAY FROM THE PLAINS INTO THE MIDWEST/GREAT LAKES REGION AND NORTHEAST...AS WELL AS THE MS/TN VALLEYS AND SOUTH FL. MANY OF THESE AREAS WILL HAVE A RISK OF VERY ISOLATED PULSE-TYPE SEVERE STORMS. THE MOST ORGANIZED SEVERE THREAT WILL BE IN THE CENTRAL/SOUTHERN PLAINS. ...CO/NM/KS/OK/TX... SOUTHERN FRINGE OF STRONGER SOUTHWESTERLY MID LEVEL WINDS WILL BE MAINTAINED TODAY ACROSS PARTS OF NM/WEST TX...WITH 20-30 KNOT 500MB FLOW EXPECTED THIS AFTERNOON. LOW LEVEL WINDS ARE BACKED TO SOUTHEASTERLY ACROSS THIS REGION...TRANSPORTING RICHER MOISTURE WESTWARD INTO THE FOOTHILLS AND HIGHER TERRAIN OF EASTERN NM/CO. STRONG HEATING IN THIS REGION WILL LIKELY RESULT IN SCATTERED THUNDERSTORM ACTIVITY DURING THE MID/LATE AFTERNOON. SUFFICIENT CAPE AND VEERING WINDS WITH HEIGHT SUGGEST A POTENTIAL FOR SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. ENHANCED UPSLOPE NEAR THE PALMER/RATON RIDGES MAY AID DEVELOPMENT. OTHER HIGH-BASED STORMS ARE LIKELY IN DEEP MIXED BOUNDARY LAYER SOUTHWARD INTO WEST TX. THIS ACTIVITY WILL SPREAD SLOWLY EASTWARD THIS EVENING INTO AN INCREASINGLY MORE MOIST/UNSTABLE AND MORE STRONGLY SHEARED ENVIRONMENT. THREAT OF SUPERCELLS WILL BE MAINTAINED UNTIL AFTER DARK...WITH ISOLATED TORNADOES POSSIBLE OVER THE NORTHERN TX PANHANDLE AND SOUTHERN KS WHERE STRONGEST VERTICAL SHEAR PROFILES ARE ANTICIPATED. MCS MAY FORM OVERNIGHT...SPREADING INTO CENTRAL KS AND NORTHWEST OK. ...CO/WY... WEAK UPSLOPE FLOW PATTERN WILL BE PRESENT TODAY INTO NORTHEAST CO AND EASTERN WY...WITH DEWPOINTS IN THE 40S AND FULL SUNSHINE. FORECAST SOUNDINGS FOR THIS AFTERNOON IN THIS AREA SHOW FAVORABLE DEEP LAYER SHEAR AND STEEP LAPSE RATES...ALONG WITH MUCAPE AROUND 500 J/KG. SCATTERED CONVECTION IS EXPECTED TO FORM OVER THE FOOTHILLS OF THE FRONT RANGE AND POSSIBLY THE BLACK HILLS...AND SPREAD SLOWLY EASTWARD. A FEW SUPERCELLS ARE POSSIBLE WITH A RISK OF HAIL AND GUSTY WINDS. SEVERE ACTIVITY IS EXPECTED TO REMAIN RATHER ISOLATED. ...UPPER MS VALLEY AND GREAT LAKES REGION... VISIBLE SATELLITE AND RADAR IMAGERY SHOW SCATTERED THUNDERSTORMS ACROSS MUCH OF IA/WI/MI THIS MORNING. THIS TREND IS LIKELY TO CONTINUE THROUGH THE AFTERNOON AS MCV FROM OVERNIGHT CONVECTION TRACKS FROM IA ACROSS WI. THREAT OF IS0LATED SEVERE STORMS IS EXPECTED THIS AFTERNOON ACROSS PARTS OF IA/IL AND SOUTHERN WI. PLEASE REFER TO MESOSCALE DISCUSSION NUMBER 1029 FOR FURTHER DETAILS. ...IL/IN/KY/TN/AL... PATTERN IS VERY SIMILAR TO LAST TWO DAYS...WITH AMPLE LOW LEVEL MOISTURE IN PLACE ACROSS THIS REGION AND STRONG DAYTIME HEATING. MLCAPE VALUES OVER 3000 J/KG THROUGHOUT THIS AREA WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. VERTICAL SHEAR IS VERY WEAK...SUGGESTING MULTICELL OR PULSE-TYPE SEVERE ACTIVITY IS POSSIBLE. WET MICROBURSTS AND MARGINAL HAIL ARE THE MOST LIKELY THREATS. ACTIVITY SHOULD DIMINISH SHORTLY AFTER SUNSET. ...NY/PA/NJ... MORNING SURFACE ANALYSIS SHOWS POCKET OF VERY MOIST AND POTENTIALLY UNSTABLE AIR REMAINING ACROSS PARTS OF NY/PA. EARLY CU DEVELOPMENT OVER THIS REGION SUGGESTS THE THREAT OF SCATTERED AFTERNOON THUNDERSTORMS. VERTICAL SHEAR IS WEAK...WITH 500MB WIND SPEEDS FORECAST TO BE ONLY 5-10 KNOTS. HOWEVER...DEGREE OF INSTABILITY AND WARM LOW LEVEL TEMPERATURES /19C AT 850MB/ SUGGESTS A THREAT OF ISOLATED PULSE-TYPE SEVERE STORMS CAPABLE OF GUSTY WINDS AND HAIL. OVERALL COVERAGE OF SEVERE STORMS SHOULD BE LIMITED BY WEAK SHEAR...SO WILL ONLY MAINTAIN LOW SEVERE PROBABILITIES. ...FL... DEEP NORTHEASTERLY FLOW ACROSS THE FL PENINSULA SHOULD FOCUS AFTERNOON THUNDERSTORM DEVELOP ALONG THE WESTERN/SOUTHERN SEA-BREEZE TODAY. VERY MOIST/UNSTABLE AIR MASS SUGGESTS A POTENTIAL FOR GUSTY WINDS AND HAIL IN STRONGEST CELLS. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED TODAY. ..HART/GRAMS.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 20:04:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 16:04:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302002 SWODY1 SPC AC 302001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT TUE MAY 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN IA/SRN WI/NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN NY AND VICINITY... ...PARTS OF THE CENTRAL AND SRN PLAINS... STORMS CONTINUE TO DEVELOP WITHIN MODERATELY-UNSTABLE AIRMASS OVER PARTS OF KS/OK...AND STORM INITIATION IS NOW OCCURRING WWD ACROSS THE HIGH PLAINS INTO ERN CO/NERN NM WHERE DRIER BOUNDARY LAYER/MORE MARGINAL INSTABILITY EXISTS. WITH ELY COMPONENT TO THE LOW-LEVEL FLOW BENEATH 20 TO 30 KT MID-LEVEL WSWLYS...SHEAR SUFFICIENT FOR ORGANIZED/ROTATING STORMS EXISTS. ALONG WITH THREAT FOR HAIL AND LOCALLY-DAMAGING WINDS NOW EVIDENT ACROSS PARTS OF KS/OK...SEVERE THREAT -- MAINLY IN THE FORM OF LOCALLY-DAMAGING WIND GUSTS -- SHOULD ALSO INCREASE ACROSS THE HIGH PLAINS OVER THE NEXT FEW HOURS. AS SELY LOW-LEVEL JET DEVELOPS ACROSS W TX/WRN OK/WRN KS INTO ERN PORTIONS OF CO/NM...EXPECT ONE OR MORE MCS TO EVOLVE AND ROLL SEWD ACROSS THE HIGH PLAINS...WITH LIMITED SEVERE THREAT POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...PARTS OF THE NORTHEAST... DESPITE WEAK SHEAR...MEAN-LAYER CAPE AS HIGH AS 3000 J/KG IS CONTRIBUTING TO A CLUSTER OF THUNDERSTORMS ACROSS ERN NY ATTM...WITH OTHER/MORE ISOLATED STORMS DEVELOPING ACROSS PARTS OF VT/NY/PA SWD INTO NRN VA. DUE TO PERSISTENCE OF STORMS...COLD POOL APPEARS TO BE DEVELOPING WITH THE STORM CLUSTER OVER E CENTRAL/NERN NY NEAR AND W OF GFL /GLEN FALLS NY/...WHICH IS RESULTING IN SOME MESOSCALE ORGANIZATION. THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL WILL CONTINUE ACROSS THIS AREA...PARTICULARLY WITH THE MORE ORGANIZED CLUSTER OF STORMS. ...UPPER MIDWEST... WEAK VORT MAX WILL CONTINUE DRIFTING NWD ACROSS SRN WI...WHILE THUNDERSTORMS PERSIST INVOF THIS FEATURE. THOUGH DEEP-LAYER WIND FIELD REMAINS WEAK...MODERATE INSTABILITY WILL CONTRIBUTE TO A LIMITED HAIL/WIND THREAT WITH STRONGER STORMS INVOF VORT MAX. THREAT SHOULD DIMINISH THIS EVENING AS AIRMASS STABILIZES. ..GOSS.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 20:15:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 16:15:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302012 SWODY1 SPC AC 302011 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0311 PM CDT TUE MAY 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN IA/SRN WI/NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN NY AND VICINITY... CORRECTED TO REMOVE SEE TEXT LABEL FROM FL ...PARTS OF THE CENTRAL AND SRN PLAINS... STORMS CONTINUE TO DEVELOP WITHIN MODERATELY-UNSTABLE AIRMASS OVER PARTS OF KS/OK...AND STORM INITIATION IS NOW OCCURRING WWD ACROSS THE HIGH PLAINS INTO ERN CO/NERN NM WHERE DRIER BOUNDARY LAYER/MORE MARGINAL INSTABILITY EXISTS. WITH ELY COMPONENT TO THE LOW-LEVEL FLOW BENEATH 20 TO 30 KT MID-LEVEL WSWLYS...SHEAR SUFFICIENT FOR ORGANIZED/ROTATING STORMS EXISTS. ALONG WITH THREAT FOR HAIL AND LOCALLY-DAMAGING WINDS NOW EVIDENT ACROSS PARTS OF KS/OK...SEVERE THREAT -- MAINLY IN THE FORM OF LOCALLY-DAMAGING WIND GUSTS -- SHOULD ALSO INCREASE ACROSS THE HIGH PLAINS OVER THE NEXT FEW HOURS. AS SELY LOW-LEVEL JET DEVELOPS ACROSS W TX/WRN OK/WRN KS INTO ERN PORTIONS OF CO/NM...EXPECT ONE OR MORE MCS TO EVOLVE AND ROLL SEWD ACROSS THE HIGH PLAINS...WITH LIMITED SEVERE THREAT POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...PARTS OF THE NORTHEAST... DESPITE WEAK SHEAR...MEAN-LAYER CAPE AS HIGH AS 3000 J/KG IS CONTRIBUTING TO A CLUSTER OF THUNDERSTORMS ACROSS ERN NY ATTM...WITH OTHER/MORE ISOLATED STORMS DEVELOPING ACROSS PARTS OF VT/NY/PA SWD INTO NRN VA. DUE TO PERSISTENCE OF STORMS...COLD POOL APPEARS TO BE DEVELOPING WITH THE STORM CLUSTER OVER E CENTRAL/NERN NY NEAR AND W OF GFL /GLEN FALLS NY/...WHICH IS RESULTING IN SOME MESOSCALE ORGANIZATION. THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL WILL CONTINUE ACROSS THIS AREA...PARTICULARLY WITH THE MORE ORGANIZED CLUSTER OF STORMS. ...UPPER MIDWEST... WEAK VORT MAX WILL CONTINUE DRIFTING NWD ACROSS SRN WI...WHILE THUNDERSTORMS PERSIST INVOF THIS FEATURE. THOUGH DEEP-LAYER WIND FIELD REMAINS WEAK...MODERATE INSTABILITY WILL CONTRIBUTE TO A LIMITED HAIL/WIND THREAT WITH STRONGER STORMS INVOF VORT MAX. THREAT SHOULD DIMINISH THIS EVENING AS AIRMASS STABILIZES. ..GOSS.. 05/30/2006  From SwoDy1 at goshenarc.org Thu May 4 01:02:54 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 03 May 2006 21:02:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040100 SWODY1 SPC AC 040058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT WED MAY 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM PARTS OF THE SRN PLAINS INTO THE OZARK PLATEAU.... CLOSED LOW WILL BEGIN TO GRADUALLY LIFT AWAY FROM THE NORTHERN MINNESOTA BORDER AREA OVERNIGHT...BUT BELT OF STRONG MID/UPPER FLOW WILL PERSIST IN BASE OF BROADER SCALE TROUGH ALONG THE CENTRAL U.S./CANADIAN BORDER. UPSTREAM...ANOTHER CLOSED LOW APPEARS TO BE EVOLVING ACROSS PARTS OF CALIFORNIA/THE INTERMOUNTAIN WEST...IN A MORE SOUTHERN BRANCH OF WESTERLIES...AS A SIGNIFICANT EMBEDDED JET STREAK DIGS OFF THE CALIFORNIA COAST. AHEAD OF THIS FEATURE...A STRONG SUBTROPICAL STREAM IMPULSE/JET STREAK IS NOSING INTO THE SOUTHWESTERN U.S./MEXICO BORDER AREA. ...SOUTHERN PLAINS INTO THE OZARKS... SURFACE RIDGE CONTINUES TO NOSE THROUGH THE CENTRAL PLAINS BENEATH CONFLUENT BELTS OF WESTERLIES. ASSOCIATED SURFACE FRONT IS NOW ADVANCING THROUGH THE OZARKS/NORTHERN OKLAHOMA AND THE TEXAS/OKLAHOMA PANHANDLE REGION...BUT CONVECTIVE DEVELOPMENT HAS BEEN SPARSE IN COVERAGE...LIMITED TO DISTINCT AREAS OF STRONGER MID/UPPER FORCING. ONE OF THESE AREAS IS CURRENTLY OVER THE MISSOURI OZARKS...WHERE WEAK SOUTHERN BRANCH PERTURBATION...PERHAPS CONVECTIVELY INDUCED... HAS AIDED ANOTHER SMALL CONVECTIVE CLUSTER. AS STRONGER MID/UPPER FORCING CONTINUES EASTWARD ACROSS THE MIDDLE MISSISSIPPI VALLEY...INTO ENVIRONMENT SUBSTANTIALLY MODIFIED BY EARLIER CONVECTION...A GRADUAL WEAKENING TREND IS EXPECTED THROUGH LATE EVENING. PRIMARY CONVECTIVE DEVELOPMENT SEEMS LIKELY TO PROCEED ACROSS PARTS OF WEST CENTRAL/NORTHWEST TEXAS INTO THE RED RIVER VALLEY. ONGOING CONVECTIVE CLUSTER EVOLVING NEAR/SOUTHEAST OF LUBBOCK SEEMS LIKELY TO BE SUPPORTED BY MOIST INFLOW OF 40 KT SOUTHERLY LOW-LEVEL JET DEVELOPING ACROSS WESTERN TEXAS. LARGE-SCALE ASCENT WILL BE ENHANCED BY STRENGTHENING DIVERGENCE ASSOCIATED WITH COUPLED SUBTROPICAL AND POLAR JETS...AND SUBSTANTIAL EXPANSION OF CONVECTIVE CLUSTER IS EXPECTED THROUGH 06Z. MID-LEVEL FLOW IS GENERALLY WEAK...BUT LARGE CAPE WILL REMAIN SUPPORTIVE OF HAIL POTENTIAL...AND RELATIVE HUMIDITIES ARE LOW ENOUGH TO SUPPORT ISOLATED DOWNBURSTS...POSSIBLY THE EVOLUTION OF ONE OR MORE COLD POOLS WITH STRONG GUSTY WINDS. ...TENNESSEE VALLEY... WEAK FLOW REGIME AND STABILIZING LOW-LEVEL ENVIRONMENT SUGGEST ANY FURTHER SEVERE THREAT WITH ONGOING CONVECTIVE CLUSTER WILL BE SHORT LIVED. STORMS SHOULD WEAKEN THIS EVENING AS THEY PROGRESS ACROSS MIDDLE TENNESSEE INTO THE SOUTHERN APPALACHIANS. ..KERR.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 05:58:38 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 01:58:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040556 SWODY1 SPC AC 040554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT THU MAY 04 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EVE FROM THE ARKLATEX EASTWARD INTO THE TENNESSEE VALLEY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EVE ACROSS PARTS OF THE SRN PLAINS.... MODELS INDICATE THAT BROAD TROUGHING WILL PERSIST THROUGH THIS FORECAST PERIOD IN THE NORTHERN BRANCH OF THE POLAR WESTERLIES...AND EXPAND EASTWARD FROM THE UPPER MIDWEST/EAST CENTRAL CANADIAN PROVINCES TOWARD THE CANADIAN MARITIMES/NORTH ATLANTIC COAST. AS THIS OCCURS...IMPULSES ARE PROGGED TO CONSOLIDATE IN UPSTREAM SOUTHERN BRANCH TROUGH ACROSS THE INTERMOUNTAIN WEST. EVENTUALLY...A CLOSED MID-LEVEL CIRCULATION IS EXPECTED TO EVOLVE OVER THE GREAT BASIN...AND TROUGHING TO THE SOUTH OF THIS FEATURE WILL COME INCREASINGLY IN PHASE WITH THE SUBTROPICAL STREAM. DOWNSTREAM OF THE SOUTHERN ROCKIES THROUGH THE SOUTH ATLANTIC COAST STATES...MID/UPPER FLOW REGIME WILL REMAIN WEAK...BETWEEN CONFLUENT BELTS OF POLAR WESTERLIES AND THE SUBTROPICAL STREAM. HOWEVER...WITH THE UPPER PATTERN SUPPORTING SOUTHWARD BUILDING SURFACE RIDGE OUT OF CANADA TO THE LEE OF THE ROCKIES... MOIST...POTENTIALLY UNSTABLE AIR WILL BECOME GENERALLY CONFINED TO THIS REGION. FRONT WILL JUST BE ADVANCING INTO THE LOWER OHIO VALLEY AND LOWER GREAT LAKES REGION AT 12Z...BUT SIGNIFICANT MOISTURE RETURN IN WAKE OF PRIOR FRONTAL PASSAGE TO THE LEE OF THE APPALACHIANS AND ASSORTMENT OF OUTFLOW BOUNDARIES ACROSS THE TENNESSEE VALLEY IS NOT ANTICIPATED. ...ARKLATEX THRU NRN GULF STATES/TENNESSEE VALLEY... CONSIDERABLE UNCERTAINTY EXISTS ACROSS THIS AREA CONCERNING DETAILS OF CONVECTIVE DEVELOPMENT. BUT...FRONTAL ZONE ADVANCING SOUTH OF THE LOWER OHIO VALLEY AND OZARK PLATEAU...AND FRONTAL ZONE/OUTFLOW BOUNDARIES EXTENDING ACROSS THE SOUTHERN APPALACHIANS INTO THE TENNESSEE VALLEY...WILL PROVIDE FOCUS FOR INITIATION OF STORMS. THIS SEEMS LIKELY TO OCCUR AS EARLY AS MID DAY AS HEATING ERODES RELATIVELY WEAK INHIBITION. THOUGH SHEAR/FLOW WILL BE WEAK...MIXED LAYER CAPE OF 1500 TO 2000 J/KG BY PEAK HEATING WILL BE SUFFICIENT FOR A FEW VIGOROUS UPDRAFTS WITH DAMAGING WIND GUSTS AND SOME HAIL. A CONVECTIVELY GENERATED MID-LEVEL CYCLONIC VORTICITY CENTER COULD PROVIDE A FOCUS FOR ANOTHER CLUSTER OF STORMS ACROSS THE ARKLATEX INTO THE NORTH CENTRAL GULF STATES THIS EVENING INTO THE OVERNIGHT HOURS. ...SOUTHERN PLAINS... LARGE CONVECTIVE CLUSTER IS EXPECTED TO WEAKEN EARLY IN THE DAY ACROSS THE RED RIVER VALLEY/NORTHERN TEXAS. OUTFLOW BOUNDARY GENERATED BY THIS FEATURE...AND SURFACE FRONT ADVANCING INTO NORTHERN/NORTHWEST TEXAS...ARE THEN EXPECTED TO PROVIDE FOCUS FOR NEW ACTIVITY. THIS MOST LIKELY WILL NOT OCCUR UNTIL VERY LATE IN THE AFTERNOON OR EVENING...AS STABILIZING INFLUENCE OF EARLY ACTIVITY WANES AND LARGE-SCALE ASCENT INCREASES WITH SUBTROPICAL STREAM IMPULSE/JET STREAK. GIVEN CONTINUING PRESENCE OF MOIST BOUNDARY LAYER AND STEEP MID-LEVEL LAPSE RATES...MIXED LAYER CAPE OF 2000 TO 3000 J/KG IS EXPECTED BY PEAK HEATING. THIS ENVIRONMENT WILL BE SUPPORTIVE OF BOTH INTENSE UPDRAFTS AND DOWNDRAFTS...WITH POTENTIAL FOR LARGE HAIL/DAMAGING WIND GUSTS. MODELS SUGGEST A WEAK TO MODERATE SOUTHERLY LOW-LEVEL JET DEVELOPING INTO THE TEXAS HILL COUNTRY BY THIS EVENING...WHICH COULD PROVIDE SUPPORT FOR ANOTHER LARGE MESOSCALE CONVECTIVE SYSTEM. ...OHIO VALLEY INTO THE LOWER GREAT LAKES... MOISTURE RETURN WILL BE LIMITED AHEAD OF FRONT ADVANCING EAST OF THE LOWER GREAT LAKES. THIS IS EXPECTED TO CONFINE CAPE TO VALUES AT OR BELOW 500 J/KG...BUT FORCING ON TAIL END OF FAIRLY VIGOROUS SHORT WAVE TROUGH IS EXPECTED TO BE SUFFICIENT FOR SCATTERED THUNDERSTORMS THIS AFTERNOON ACROSS PARTS OF NEW YORK/ PENNSYLVANIA. THOUGH UPDRAFTS SHOULD BE WEAK...DEEP MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS IN PRESENCE OF WEAK TO MODERATE MEAN FLOW COULD SUPPORT LOCALLY DAMAGING WIND GUSTS. THOUGH FORCING WILL BE WEAKER...WIDELY SCATTERED STORMS COULD DEVELOP WESTWARD ALONG FRONT INTO PARTS OF THE LOWER OHIO VALLEY BY EARLY EVENING...WHERE THERMODYNAMIC ENVIRONMENT MAY BE MORE FAVORABLE FOR HAIL NEAR SEVERE LIMITS. ...GREAT BASIN... FRONTAL ZONE ACROSS SOUTH CENTRAL UTAH INTO WEST CENTRAL COLORADO IS EXPECTED TO AGAIN BE A FOCUS FOR WIDELY SCATTERED LATE AFTERNOON STORMS. MOISTURE IS LIMITED...BUT VERY STEEP LAPSE RATES BENEATH COLD MID-LEVEL TROUGH WILL PROVIDE AT LEAST SOME POTENTIAL FOR HAIL/WIND GUSTS APPROACHING/BRIEFLY EXCEEDING SEVERE LIMITS. ..KERR/GRAMS.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 12:47:13 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 08:47:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041244 SWODY1 SPC AC 041242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT THU MAY 04 2006 VALID 041300Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF SW AND S CNTRL TX... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SRN/CNTRL AND SW TX... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX AND TN VLY TO THE SRN APLCNS... ...SYNOPSIS... WEAK...SLOWLY PROGRESSIVE SPLIT FLOW PATTERN WILL PREVAIL THIS PERIOD ACROSS THE LWR 48. SEVERE TSTM CHANCES SHOULD REMAIN CONFINED TO THE DIFFLUENT SRN BRANCH THAT WILL EXTEND E/NE INTO THE SRN PLNS...DOWNSTREAM FROM CNTRL/SRN CA CLOSED LOW. AT LWR LEVELS...EXPANSIVE SURFACE RIDGE IN WAKE OF NRN STREAM LOW NOW CROSSING ONTARIO WILL CONTINUE TO PRESS S/SE INTO THE SRN PLNS...THE MID/LWR MS VLYS AND THE ERN GRT LKS. EFFECTIVE COLD FRONT MARKING LEADING EDGE OF RIDGE WILL BE SHUNTED S INTO CNTRL TX/SE OK AND CNTRL AR TODAY BY COMPOSITE OUTFLOW FROM OVERNIGHT MCSS. FARTHER E...EXPECT WEAK WARM FRONT THAT HELPED SPAWN STORMS IN MO/AR AND THE LWR TN MS VLY YESTERDAY WILL REDEVELOP E TOWARD THE SRN APLCNS AND WEAKEN. ...S CNTRL TX INTO SE NM... DISSIPATING NRN/CNTRL TX MCS HAS LEFT A WELL-DEFINED OUTFLOW BOUNDARY THAT EXTENDS FROM THE ERN/SRN HILL COUNTRY W ACROSS THE EDWARDS PLATEAU TO NEAR MAF. THE WRN PART OF THE BOUNDARY MAY EDGE A BIT N TODAY BEFORE BEING INTERCEPTED BY SYNOPTIC COLD FRONT NOSING S FROM NEAR LBB. THE COMBINED BOUNDARIES SHOULD MORE OR LESS STALL ALONG ROUGHLY A WNW/ESE AXIS FROM NEAR MAF TO NEAR SJT ...AND LIKELY WILL SERVE AS A FOCUS FOR NEW STORM DEVELOPMENT LATE TODAY. SATELLITE LOOPS SUGGEST PRESENCE OF AN UPR LEVEL IMPULSE NOW OVER SW NM/NRN SONORA THAT SHOULD REACH W CNTRL AND SW TX BY LATE IN THE DAY. SATELLITE ALSO SUGGESTS THAT HEATING WILL BE STRONG IN WAKE OF MCS DEBRIS FROM THE HILL COUNTRY W INTO THE PERMIAN BASIN/SE NM. QUALITY BOUNDARY LAYER MOISTURE IS ALREADY PRESENT AS FAR W AS DRT/SJT...AND SOME WWD ADVECTION OF MOISTURE LIKELY WILL OCCUR INVOF STALLING FRONT/OUTFLOW BOUNDARY THROUGH THE DAY. THUS... EXPECT THAT STRONG INSTABILITY WILL DEVELOP...WITH MLCAPE OF 2000 TO 3000 J/KG LIKELY BY PEAK HEATING. COMBINATION OF STRONG INSTABILITY...WEAK BUT INCREASING LARGE SCALE ASCENT...AND 30+ KT WSWLY MID LEVEL FLOW SHOULD SUPPORT SUPERCELLS WITH BOTH VERY LARGE HAIL AND HIGH WIND. IN ADDITION...ASSUMING THAT THE SURFACE BOUNDARIES DO INDEED BECOME NEARLY STATIONARY...POTENTIAL WILL ALSO EXIST FOR TORNADOES WITH ANY DISCRETE RIGHT-MOVING STORMS THAT MOVE ALONG THE FRONT. GOOD MOISTURE AVAILABILITY...DIURNAL STRENGTHENING OF MODERATE SLY LLJ...AND EWD PROGRESSION OF SAME AS UPR IMPULSE CONTINUES EWD ALL SUGGEST THAT THE TX STORMS WILL EVOLVE INTO A LARGE COMPLEX. THIS SYSTEM SHOULD MOVE E/SE ACROSS S CNTRL AND PERHAPS SE TX THROUGH EARLY FRIDAY. ...ARKLATEX/NRN GULF STATES/TN VLY... MODERATE TO STRONG SURFACE HEATING SHOULD OCCUR FROM THE ARKLATEX E INTO THE PARTS OF MS...AL AND GA TODAY...S AND E OF AFOREMENTIONED MCS OUTFLOW BOUNDARIES. SYNOPTIC SCALE FORCING FOR ASCENT WILL BE WEAK. BUT COMPOSITE RADAR DATA SUGGEST PRESENCE OF SEVERAL MCVS EMBEDDED WITHIN THE ERN OK/N TX CONVECTIVE COMPLEXES THAT LIKELY WILL SERVE TO ENHANCE MESOSCALE ASCENT AS THEY CONTINUE GENERALLY EWD. THIS ENHANCEMENT MAY BE MAXIMIZED FROM CNTRL AR INTO NRN MS/AL...WHERE THE SYSTEMS WILL INTERACT WITH REMNANT WARM FRONT. FOCUSED UPLIFT SHOULD ALSO OCCUR ALONG COLD FRONT SETTLING SE FROM KY INTO TN. MODEST /20-25 KT/ W TO WNWLY MID LEVEL FLOW WILL LIMIT STORM ORGANIZATION AND LONGEVITY. BUT GIVEN EXPECTED DEGREE OF INSTABILITY /SBCAPE OF 1500-2000 J PER KG/ AND FORCING FOR ASCENT PROVIDED BY MCVS...EXPECT INTENSIFICATION OF EXISTING STORMS IN WEAKLY CAPPED ENVIRONMENT BY EARLY AFTERNOON. THIS ACTIVITY COULD YIELD LOCALLY DAMAGING WIND AND MARGINALLY SEVERE HAIL AS STORMS MOVE/DEVELOP E TO THE SRN SLOPES OF THE APLCNS THROUGH THE REMAINDER OF THE DAY. GIVEN LARGELY STATIC PATTERN AND PERSISTENT MOIST INFLOW...THE WIDESPREAD CONVECTION MAY SUPPORT DEVELOPMENT OF AN ADDITIONAL MCV TONIGHT OVER THE LWR TN VLY...WITH AN ATTENDANT THREAT FOR MARGINALLY SEVERE HAIL/WIND AND HEAVY RAIN. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ...GREAT BASIN... COLD FRONT ASSOCIATED WITH CA TROUGH WILL LINGER OVER THE CNTRL GRT BASIN/CNTRL RCKYS TODAY. THE BOUNDARY MAY ONCE AGAIN BE A FOCUS FOR WIDELY SCATTERED LATE AFTERNOON STORMS. MOISTURE WILL BE LIMITED...BUT VERY STEEP LAPSE RATES BENEATH MODERATE SWLY MID LEVEL FLOW ON E SIDE OF TROUGH MAY PROMOTE DEVELOPMENT OF A FEW CELLS WITH HAIL/WIND GUSTS APPROACHING/BRIEFLY EXCEEDING SEVERE LIMITS. ..CORFIDI/GRAMS.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 16:24:20 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 12:24:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041622 SWODY1 SPC AC 041620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES/GUYER.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 17:09:09 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 13:09:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041706 SWODY1 SPC AC 041705 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 1205 PM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... THUNDER GRAPHIC LINES ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES.. 05/04/2006  From SwoDy1 at goshenarc.org Thu May 4 20:01:49 2006 From: SwoDy1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 16:01:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041959 SWODY1 SPC AC 041958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT THU MAY 04 2006 VALID 042000Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER PARTS OF W-CNTRL AND CNTRL TX... ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN NM TO THE SE TX COAST... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX ACROSS NRN MS... ...ERN NM INTO CNTRL TX... 18Z MESOANALYSIS INDICATES PRESSURE FALLS IN POST-FRONTAL AIR MASS OVER THE TX PNHDL...SUGGESTING THAT FRONT SHOULD DECELERATE THIS AFTERNOON...BECOMING QUASI-STATIONARY FROM SERN NM INTO CNTRL TX. STRONG DAYTIME HEATING COUPLED WITH STEEP LAPSE RATES AND MODEST BOUNDARY-LAYER MOISTURE WILL CONTINUE TO SUPPORT FURTHER DESTABILIZATION INVOF OF THIS BOUNDARY THIS AFTERNOON WITH MLCAPES INCREASING FROM 1000-1500 J/KG OVER SERN NM INTO WRN TX...TO 2000-3000 J/KG INTO CNTRL TX. 18Z MAF SOUNDING INDICATES THAT WIND FIELDS HAVE INCREASED ABOVE 4 KM AGL WITH SUFFICIENT VERTICAL SHEAR /I.E. 30-40 KTS/ PRESENT TO SUPPORT SUPERCELL DEVELOPMENT. VISIBLE SATELLITE AND LATEST RUC GUIDANCE SUGGEST THAT TSTMS WILL DEVELOP BY MID TO LATE AFTERNOON ALONG BOTH: 1) THE IMMEDIATE HIGHER TERRAIN OF CNTRL NM...AND 2) ALONG FRONTAL ZONE ESEWD INTO CNTRL TX WITH STORMS EVENTUALLY MERGING INTO CLUSTERS OR A MCS TONIGHT AND MOVING SEWD THROUGH THE HILL COUNTRY INTO PARTS OF ERN/SERN TX. INITIAL SUPERCELL MODES WILL BE CAPABLE OF LARGE HAIL /SOME SIGNIFICANT/ AND PERHAPS A COUPLE TORNADOES...PRIOR TO EVOLVING INTO MORE OF AN OUTFLOW-DOMINANT CONVECTIVE COMPLEX WITH A THREAT OF HAIL AND HIGH WINDS. ...ARKALTEX INTO NRN MS... WELL-DEFINED MCV CONTINUES TO TRANSLATE EWD THIS AFTERNOON OVER SWRN AR WITH DEQUEEN AR PROFILER INDICATING AN ASSOCIATED NARROW CHANNEL OF 50 KT WLY FLOW AT 6 KM AGL AROUND THE SRN PERIPHERY OF THIS FEATURE. LOW-LEVEL AIR MASS ACROSS NRN LA/SRN AR IS MOIST WITH DEWPOINTS IN THE MID 60S...WHICH ARE CONTRIBUTING TO MODERATE INSTABILITY WITH MLCAPES OF 1000-2000 J/KG. GIVEN THIS MODERATE INSTABILITY AND MESOSCALE ZONE OF MODERATELY STRONG VERTICAL SHEAR...EXPECT THE THREAT OF ORGANIZED SEVERE STORMS INCLUDING SUPERCELLS TO CONTINUE EWD ALONG W-E FRONTAL BOUNDARY INTO THE MS DELTA THIS AFTERNOON INTO TONIGHT. LARGE HAIL AND LOCALLY DAMAGING WINDS APPEAR TO BE THE PRIMARY SEVERE WEATHER THREATS WITH THE MOST INTENSE STORMS. ...SERN TX INTO SRN LA... TSTMS HAVE INTENSIFIED THIS AFTERNOON ACROSS REGION AHEAD OF SECONDARY...WEAKER MCV MOVING MORE SEWD OUT OF THE HILL COUNTRY. AMBIENT AIR MASS REMAINS QUITE MOIST WITH DEWPOINTS OF 65-70 F WHICH ARE LARGELY CONTRIBUTING TO MLCAPES OF 1000-2000 J/KG. MOREOVER...HOUSTON VWP INDICATES RELATIVELY STRONG VEERING WITH HEIGHT WITH 40-45 KTS OF DEEP-LAYER SHEAR. STORMS NEAR CLL HAVE RECENTLY STRENGTHENED...AND GIVEN AMBIENT ENVIRONMENT...FURTHER INTENSIFICATION IS LIKELY THIS AFTERNOON INTO EVENING AS STORMS MOVE SEWD TOWARD THE COAST. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER HAZARDS. ...TN VALLEY SWD INTO NRN PORTIONS OF AL AND GA... REGIONAL RADAR IMAGERY INDICATE TSTMS BECOMING INCREASINGLY NUMEROUS THIS AFTERNOON FROM NEAR CBM EWD ACROSS PARTS OF NRN AL/GA TO NEAR AHN. VISIBLE SATELLITE AND MESOANALYSIS SUGGEST THAT THIS ACTIVITY IS DEVELOPING ALONG AN OUTFLOW BOUNDARY REMNANT FROM EARLIER CONVECTION. WHILE AMBIENT AIR MASS IS MOIST AND MODERATELY UNSTABLE.../MLCAPES OF 1000-1500 J/KG/ AREA VWPS AND RUC OBJECTIVE FIELDS INDICATE THAT VERTICAL SHEAR AND MID-LEVEL LAPSE RATES REMAIN QUITE MARGINAL FOR ORGANIZED...SEVERE STORMS. THUS...CATEGORICAL SLIGHT RISK HAS BEEN REMOVED. NONETHELESS...POTENTIAL WILL EXIST FOR ISOLATED WIND OR HAIL WITH THE MOST INTENSE STORMS INTO THIS EVENING. ...UPPER OH VALLEY INTO WRN/CNTRL PA AND NY... DIABATIC HEATING ALONG WITH SOME INCREASE IN LOW-LEVEL MOISTURE FROM THE SW HAVE RESULTED IN WEAK AIR MASS DESTABILIZATION AHEAD OF SURFACE FRONT THIS AFTERNOON. THUS FAR...MOST INTENSE DEEP CONVECTION HAS REMAINED N OF INTERNATIONAL BORDER OVER FAR SERN ONTARIO IN ASSOCIATION WITH SRN FRINGE OF STRONGER HEIGHT FALLS AHEAD OF UPPER LOW OVER ERN ONTARIO. THIS ACTIVITY MAY MOVE INTO PARTS OF NRN NY LATE THIS AFTERNOON OR EARLY THIS EVENING WITH ADDITIONAL STORM DEVELOPMENT POSSIBLE ALONG COLD FRONT INTO ERN OH OR WRN PA. STEEP LOW-LEVEL LAPSE RATES AND MODEST UNIDIRECTIONAL VERTICAL SHEAR MAY SUPPORT A COUPLE STRONG STORMS CAPABLE OF LOCALLY STRONG WIND GUSTS AND SOME HAIL. ...INTERMOUNTAIN W... STEEP LOW TO MID-LEVEL LAPSE RATES HAVE CONTRIBUTED TO A WEAKLY UNSTABLE ENVIRONMENT THIS AFTERNOON AHEAD OF MID-LEVEL TROUGH SLOWLY TRANSLATING EWD TOWARD THE LOWER CO VALLEY. THESE STEEP LAPSE RATES COUPLED WITH A WELL-MIXED BOUNDARY-LAYER WILL SUPPORT ISOLATED WIND/HAIL WITH THE MOST INTENSE STORMS. ..MEAD.. 05/04/2006  From swody1 at goshenarc.org Thu May 4 17:09:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 13:09:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 041706 SWODY1 SPC AC 041705 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 1205 PM CDT THU MAY 04 2006 VALID 041630Z - 051200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF CENTRAL AND SOUTHWESTERN TEXAS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN TX TO ERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX EWD TO THE SRN APPALACHIANS... THUNDER GRAPHIC LINES ...SRN PLAINS... UPPER LOW OVER NRN INTERMOUNTAIN REGION DRIFTS SWD TODAY AS S/WV TROUGH AND MID LEVEL WIND MAX MOVE EWD ACROSS AZ INTO NM TONIGHT. GRADUAL INCREASE IN MID LEVEL FLOW SPREADS EWD INTO SRN HIGH PLAINS WITH APPROACH OF UPPER IMPULSE RESULTING IN IMPROVEMENT OF DEEP LAYER SHEAR THIS AREA IN SUPPORT OF SUPERCELL DEVELOPMENT. OVERNIGHT CONVECTION HAS CLEARED OUT OF W TX WHICH IS ALLOWING RETURN OF LOW LEVEL MOISTURE N/NWWD THRU THE TRANS PECOS REGION. SURFACE FRONTAL BOUNDARY EXTENDS WWD JUST TO S OF RED RIVER VALLEY INTO SERN CORNER OF NM AND WILL MOVE ONLY SLOWLY SWD THRU THE AFTERNOON. WITH STEEP LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER PERSISTING ACROSS ALL OF SRN PLAINS EWD TO LOWER MS VALLEY...THERMODYNAMICS WILL BE MORE THAN SUFFICIENT BY MID/LATE AFTERNOON FOR SEVERE THUNDERSTORM DEVELOPMENT. WHILE THE LOW LEVEL SHEAR WILL GENERALLY BE ONLY MARGINAL...AROUND 10 KTS...30-40KT OF DEEP LAYER SHEAR IN CONCERT WITH MLCAPES BETWEEN 2000-3000 J/KG BY MID AFTERNOON EXPECTED TO FAVOR DEVELOPMENT OF SUPERCELLS. MOST LIKELY INITIATION WILL BE IN AREA OF LOW LEVEL CONVERGENCE VICINITY OF FRONTAL ZONE AND THE HIGHER TERRAIN OF ERN NM/SWRN TX WHERE HEATING WILL BE VERY STRONG. WILL CONTINUE THE MDT RISK...AS THE SHEAR AND EXPECTED UNSTABLE AIR MASS WILL RESULT IN LARGE HAIL WITH ANY SUPERCELL THAT FORMS. IN ADDITION TORNADOS ARE MORE OF A THREAT IN SRN HI PLAINS THAN ON WED WHEN DEEP LAYER SHEAR WAS NOT QUITE AS STRONG AND MOISTURE PROFILES TOOK LONGER TO RECOVER FROM OVERNIGHT CONVECTION. ...MID MS VALLEY AND GULF COAST STATES... OUTFLOW BOUNDARIES FROM OVERNIGHT STORMS STRETCH WWD FROM NRN AL/MS INTO SRN AR. WHILE LAPSE RATES AND SHEAR NOT QUITE AS FAVORABLE AS OVER SRN PLAINS...THE AIR MASS IS MOIST AND WITH AFTERNOON HEATING EXPECTED TO BECOME MODERATELY UNSTABLE. BY MID AFTERNOON WITH SURFACE TEMPERATURES RISING THRU THE 80S...SURFACE BASED THUNDERSTORMS SHOULD DEVELOP...MOST LIKELY IN CONVERGENCE VICINITY OF THE OLD OUTFLOW BOUNDARIES. STORM MODE SHOULD BE MULTI-CELL WITH PRIMARY SEVERE THREAT OF MARGINALLY SEVERE HAIL AND LOCAL DAMAGING DOWNBURSTS. ...INTERMOUNTAIN REGION... BAND OF CONVERGENCE/BAROCLINIC ZONE ON E SIDE OF UPPER TROUGH EXTENDS FROM SWRN WY TO CENTRAL NV. STRONG HEATING AND EXISTING STEEP LAPSE RATES ON S SIDE OF THIS ZONE WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. WHILE LOW LEVEL MOISTURE IS ON THE LOW SIDE...SUFFICIENT CAPE...GIVEN THE VERY STEEP LAPSE RATES AND 30-40 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW STRONG THUNDERSTORMS. MARGINALLY SEVERE HAIL AND BRIEF DAMAGING DOWNBURST WINDS WILL BE THE LIMIT OF THE THREAT FROM MID-AFTERNOON THRU THE EVENING. ...OH VLY TO THE LWR GRT LKS... MOISTURE RETURN WILL BE SCANT AHEAD OF TRAILING COLD FRONT ASSOCIATED WITH NRN STREAM IMPULSE IN ONTARIO. THIS WILL LIMIT CAPE TO AOB 500 J/KG. BUT FRONTAL UPLIFT AND FORCING FOR ASCENT ON SRN EDGE OF ONTARIO TROUGH MAY BE SUFFICIENT FOR SCATTERED AFTERNOON TSTMS ACROSS NY/PA. DEEPLY MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS COULD SUPPORT LOCALLY DAMAGING GUSTS. FARTHER SW ALONG THE FRONT...UVV SHOULD BE WEAKER. BUT WIDELY SCATTERED STORMS SHOULD DEVELOP SW INTO THE LWR OH VLY BY EARLY EVENING...WHERE THERMODYNAMIC SETUP COULD SUPPORT A COUPLE CELLS WITH MARGINALLY SEVERE HAIL. ..HALES.. 05/04/2006  From swody1 at goshenarc.org Fri May 5 00:56:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 04 May 2006 20:56:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050054 SWODY1 SPC AC 050052 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0752 PM CDT THU MAY 04 2006 VALID 050100Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS PARTS OF THE SRN PLAINS.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF THE CNTRL GULF STATES.... A COLD INTRUSION TO THE LEE OF THE ROCKIES HAS OCCURRED IN ASSOCIATION WITH A BROAD NORTHERN BRANCH TROUGH NOW SLOWLY SHIFTING THROUGH THE EASTERN CANADIAN PROVINCES...AND PARTS OF THE UPPER MIDWEST INTO THE NORTHEAST STATES. SURFACE RIDGE HAS BECOME CENTERED BENEATH CONFLUENCE OF NORTHERN AND SOUTHERN BRANCHES OF WESTERLIES...ACROSS THE NORTHERN/CENTRAL PLAINS...WITH ASSOCIATED FRONTAL ZONE NOW EXTENDING FROM THE LOWER GREAT LAKES THROUGH THE LOWER OHIO VALLEY INTO THE SOUTH CENTRAL HIGH PLAINS. SEVERAL CONVECTIVE OUTFLOWS HAVE SUPPRESSED DEEPER BOUNDARY LAYER MOISTURE TO THE SOUTH OF THIS FRONTAL ZONE...AND WILL REMAIN THE FOCUS FOR THE PRIMARY CONVECTIVE DEVELOPMENT THROUGH THE REMAINDER OF THIS FORECAST PERIOD. ...SOUTHERN PLAINS... OUTFLOW BOUNDARY...EXTENDING ACROSS THE TEXAS HILL COUNTRY AND TRANSPECOS REGION...AND SURFACE FRONTAL ZONE...ACROSS THE TEXAS SOUTH PLAINS INTO EASTERN NEW MEXICO...ARE PROVIDING THE FOCUS FOR ONGOING SCATTERED VIGOROUS THUNDERSTORM ACTIVITY. LOW-LEVEL FLOW ACROSS THIS REGION IS RATHER WEAK...BUT VEERING PROFILES WITH HEIGHT BENEATH MODERATE WESTERLY MID LEVEL FLOW IS CONTRIBUTING TO SUFFICIENT SHEAR FOR ISOLATED SUPERCELLS IN ENVIRONMENT WITH MIXED LAYER CAPE OF 2000 TO 3000 J/KG. THIS ACTIVITY MAY PERSIST THROUGH 02-03Z...BUT WITH ONSET OF SURFACE COOLING...NOCTURNAL SOUTHERLY LOW-LEVEL JET SEEMS LIKELY TO SUPPORT CONSOLIDATING/EXPANDING CONVECTIVE CLUSTER NEAR/EAST OF SAN ANGELO. AS THIS OCCURS...UNSATURATED LOW/MID-LEVELS WILL ENHANCE EVAPORATIVE COOLING NEAR HEAVY PRECIPITATION CORES...AND A DOWNBURST OR TWO MAY OCCUR WITH POTENTIALLY DAMAGING WINDS ON OUTWARD SURGING GUST FRONTS. ...LOWER MISSISSIPPI VALLEY/GULF STATES... CONVECTIVELY GENERATED UPPER IMPULSE/MID-LEVEL CYCLONIC VORTICITY CENTER IS PROVIDING SUPPORT FOR ONGOING CONVECTIVE CLUSTER NOW SPREADING ACROSS THE LOWER MISSISSIPPI VALLEY. THIS IS EMBEDDED WITHIN GENERALLY WEAK FLOW REGIME BETWEEN CONFLUENT BELTS OF POLAR WESTERLIES TO THE NORTH...AND SUBTROPICAL WESTERLIES TO THE SOUTH. HOWEVER...THERMODYNAMIC PROFILES SEEM SUPPORTIVE OF A CONTINUING RISK FOR MARGINALLY SEVERE HAIL/GUSTY WINDS WITH CONVECTIVE SYSTEM AS IT SPREADS ACROSS NORTHERN/CENTRAL MISSISSIPPI THROUGH 03-04Z. THEREAFTER...CONVECTION IS EXPECTED TO WEAKEN IN MORE STABLE/ STABILIZING ENVIRONMENT. ..KERR.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 05:46:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 01:46:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050544 SWODY1 SPC AC 050542 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1242 AM CDT FRI MAY 05 2006 VALID 051200Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE SRN PLAINS.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SOUTH ATLANTIC COAST STATES.... SHORT WAVE IMPULSE ON NOSE OF SEASONABLY STRONG NORTH CENTRAL/NORTHEAST PACIFIC POLAR JET IS ALREADY APPROACHING THE BRITISH COLUMBIA/PACIFIC NORTHWEST COAST. MOST VIGOROUS PORTION OF SYSTEM IS PROGGED TO CONTINUE INLAND ACROSS THE CASCADES AND CANADIAN ROCKIES TODAY...WHILE WEAKER SOUTHERN PORTION DIGS IN SOUTHERN STREAM...TOWARD NORTHERN/CENTRAL CALIFORNIA. IN RESPONSE TO THESE DEVELOPMENTS...SIGNIFICANT SOUTHERN BRANCH TROUGH WILL BE FORCED EASTWARD OUT OF THE GREAT BASIN/SOUTHERN PLATEAU. MODELS SUGGEST THAT THIS WILL OCCUR IN A MORE OR LESS PIECE MEAL FASHION...WITH A SERIES OF SMALLER SCALE IMPULSES PROGRESSING EAST OF THE ROCKIES INTO THE SOUTH CENTRAL STATES. FARTHER DOWNSTREAM...TO THE SOUTH/EAST OF AN AMPLIFYING NORTHERN BRANCH TROUGH...A CONVECTIVELY GENERATED/ENHANCED IMPULSE IN THE WEAKER SOUTHERN STREAM IS FORECAST TO LIFT OUT OF THE TENNESSEE VALLEY. SYSTEM IS EXPECTED TO BECOME INCREASINGLY SHEARED AS IT CROSSES THE CENTRAL/SOUTHERN APPALACHIANS BY MID DAY...BEFORE CONTINUING THROUGH MID/SOUTHERN ATLANTIC COASTAL AREAS LATER TODAY/TONIGHT. ...SOUTHERN PLAINS... CONSIDERABLE STRENGTHENING OF MID-LEVEL FLOW /ON THE ORDER OF 40 TO 50 KT/ IS FORECAST IN A CYCLONIC BELT ACROSS THE SOUTHERN ROCKIES/NORTHERN MEXICAN PLATEAU THROUGH MUCH OF TEXAS TODAY. WHILE THIS WILL CONTRIBUTE TO AN INCREASINGLY FAVORABLE KINEMATIC ENVIRONMENT FOR SUPERCELLS AND SEVERE STORMS AS COMPARED TO RECENT DAYS...CONVECTIVE POTENTIAL THIS PERIOD IS MORE UNCERTAIN DUE TO INFLUENCE OF SEVERAL DAYS OF WIDESPREAD CONVECTION. CONSIDERABLE CONVECTION COULD BE ONGOING EARLY IN THE PERIOD ACROSS PARTS OF SOUTHERN AND EASTERN TEXAS...ASSOCIATED WITH REMNANTS OF WEAKENING CONVECTIVE CLUSTER...WITH NEW DEVELOPMENT POSSIBLE ACROSS THE SOUTH PLAINS IN ASSOCIATION WITH LEAD IMPULSE PROGRESSING EAST OF THE SOUTHERN ROCKIES. STEEP LAPSE RATE ENVIRONMENT AND STRONGER SURFACE HEATING MAY ULTIMATELY BE CONFINED TO THE IMMEDIATE VICINITY OF THE RIO GRANDE AND PECOS VALLEYS. VERY MOIST AIR IS IN PLACE ACROSS THE RIO GRANDE VALLEY WITH 70F DEW POINTS AS FAR NORTH AS DEL RIO. ADVECTION OF THIS MOIST TONGUE WESTWARD THROUGH THE PECOS VALLEY SHOULD OCCUR TODAY...AND WILL CONTRIBUTE TO AT LEAST A NARROW CORRIDOR OF MODERATE TO STRONG INSTABILITY...WITH MIXED LAYER CAPE REACHING 2000-3000 J/KG BY PEAK HEATING. AS NEXT UPPER IMPULSE PROGRESSES EAST OF THE SOUTHERN ROCKIES THIS AFTERNOON...INITIATION OF ADDITIONAL INTENSE CONVECTION IS EXPECTED ALONG OUTFLOW/SURFACE FRONT ADVANCING SOUTHWARD TOWARD THE MIDLAND AREA...AND ALONG DRY LINE NEAR THE PECOS RIVER. ISOLATED SUPERCELLS ARE EXPECTED...WITH POTENTIAL FOR VERY LARGE HAIL AND TORNADOES. THIS ACTIVITY IS EXPECTED TO CONTINUE INTO EARLY EVENING...BEFORE EVOLVING UPSCALE INTO A STRONG/SEVERE MESOSCALE CONVECTIVE SYSTEM AS INFLOW STRENGTHENS ASSOCIATED WITH SOUTHEASTERLY LOW-LEVEL JET THROUGH THE RIO GRANDE VALLEY. ...SOUTH ATLANTIC COAST STATES... MOISTENING BOUNDARY LAYER AND STRONG SURFACE HEATING IS EXPECTED TO CONTRIBUTE TO DESTABILIZING ENVIRONMENT TO THE LEE OF THE SOUTHERN APPALACHIANS TODAY. MODELS SUGGEST MIXED LAYER CAPE WILL REACH 1000-2000 J/KG BY PEAK AFTERNOON HEATING. THIS SHOULD BE SUFFICIENT FOR SCATTERED VIGOROUS CONVECTIVE DEVELOPMENT FROM GEORGIA THROUGH THE CAROLINAS...AIDED BY FORCING ASSOCIATED WITH WEAK SOUTHERN BRANCH IMPULSE. BELT OF 20 TO 30 KT WESTERLY MID-LEVEL FLOW MAY ACCOMPANY THIS FEATURE...CONTRIBUTING TO MODERATE STORM MOTIONS...POSSIBLY ENHANCING RISK FOR DAMAGING WINDS IN STRONGER STORMS. HAIL APPROACHING OR EXCEEDING SEVERE LIMITS MAY ALSO OCCUR. ..KERR/GRAMS.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 12:42:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 08:42:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051239 SWODY1 SPC AC 051238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT FRI MAY 05 2006 VALID 051300Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NM TO THE LOWER MS RIVER VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE SOUTHEAST... ...SRN HIGH PLAINS ACROSS MUCH OF TX... SURFACE PATTERN HAS BEEN MUDDLED ACROSS THIS AREA BY EXTENSIVE CONVECTION/MCS ACTIVITY OVER THE PAST FEW NIGHTS. PRIMARY SURFACE COLD FRONT APPEARS TO EXTEND FROM THE ARKLATEX REGION W-SWWD INTO SERN NM AT 12Z...WITH MARINE AIR /70+F DEW POINTS/ REMAINING CONFINED TO DEEP SOUTH TX AND JUST OFF THE MIDDLE AND UPPER TX COAST. WEAK SURFACE LOW NOW EVIDENT OVER FAR SERN NM WILL BECOME BETTER DEFINED ALONG INTERSECTION OF COLD FRONT AND DRY LINE THROUGH THE DAY AHEAD OF PROMINENT MID/UPPER LEVEL TROUGH NOW MOVING ACROSS THE LOWER CO RIVER VALLEY. ASSOCIATED 40-50 KT WLY MID LEVEL JET WILL OVERSPREAD MUCH OF THE SRN HIGH PLAINS THROUGH THE DAY...AS LARGE SCALE PRESSURE FALLS INCREASE SSELY LOW LEVEL FLOW. THIS WILL PROVIDE A VERY FAVORABLE SETUP FOR SUPERCELLS FROM PORTIONS OF CENTRAL/SERN NM ACROSS MUCH OF WRN TX BY THE MID AFTERNOON WITH EFFECTIVE BULK SHEAR IN EXCESS OF 50 KT...DEPENDING UPON QUALITY OF BOUNDARY LAYER AIR MASS. WEDGE OF MID 60F SURFACE DEW POINTS REMAINS IN PLACE FROM THE TX BIG BEND ACROSS THE TRANS PECOS EARLY THIS MORNING. INCREASING SELY SURFACE WINDS AND LARGE SCALE PRESSURE FALLS WILL LIKELY LIFT WARM FRONT/RICHER GULF MOISTURE NWD ALONG AND WEST OF THE HILL COUNTRY THROUGH THE DAY...WITH NARROW WEDGE OF LOW-MID 50F SURFACE DEW POINTS EXTENDING INTO PORTIONS OF CENTRAL NM LATER TODAY. THIS WILL SUPPORT AN AXIS OF MODERATE TO STRONG INSTABILITY FROM SRN/CENTRAL TX NWWD INTO THE SERN NM BY THE MID TO LATE AFTERNOON. INCREASING LARGE SCALE ASCENT AND CONVERGENCE/UPSLOPE WILL BREAK CAP AND INITIATE SEVERE THUNDERSTORMS NEAR HIGHER TERRAIN AND TRIPLE POINT/DRY LINE OVER SERN NM/SWRN TX BY 22Z. SUPERCELLS WILL BE LIKELY WITHIN THIS ZONE WITH ATTENDANT THREATS OF VERY LARGE HAIL AND PERHAPS A FEW TORNADOES. TORNADO THREAT MAY INCREASE INTO THE EARLY EVENING AS ACTIVITY MOVES INTO RICHER BOUNDARY LAYER MOISTURE AND STRONGER LOW LEVEL SHEAR ACROSS THE EDWARDS PLATEAU REGION. EXPECT ACTIVITY WILL INTENSIFY INTO A SEVERE MCS AND POSSIBLY EVOLVE INTO A BOW ECHO WITH INCREASED WIND DAMAGE THREAT AS ACTIVITY SPREADS EWD ALONG INSTABILITY GRADIENT/SURFACE BOUNDARY WITH ATTENDANT SEVERE REACHING THE TX COASTAL PLAIN OVERNIGHT. ...LOWER MS RIVER VALLEY INTO THE CENTRAL GULF COAST... MCV/VORT MAX ASSOCIATED WITH MCS WHICH TRAVERSED NRN TX OVERNIGHT WAS NOW OVER NERN TX. AHEAD OF THIS FEATURE...AXIS OF RICH GULF MOISTURE IS PERSISTING ALONG THE SABINE RIVER/CENTRAL LA WHERE 12Z LCH SOUNDING INDICATES VERY STEEP LAPSE ARE IN PLACE. LOW LEVEL WINDS AND SUBSEQUENT LOW LEVEL SHEAR REMAIN RATHER WEAK. HOWEVER...20-30 KT EFFECTIVE SHEAR SHOULD SUPPORT ORGANIZED MULTICELL CLUSTERS/LINES WITH THREATS OF LARGE HAIL DAMAGING WINDS AS STORMS INCREASE AND DEVELOP SEWD TODAY. EWD EXTENT OF STRONGER STORMS WILL BE LIMITED BY CONVECTIVELY-STABILIZED AIR NOW IN PLACE OVER CENTRAL MS. ...SOUTHEAST... MODELS IN AGREEMENT IN MOVING VORT MAX/SHORTWAVE TROUGH EWD OUT OF AL AND INTO GA/SC TODAY. AHEAD OF THIS FEATURE ABUNDANT HEATING WILL DEVELOP...ESPECIALLY INTO ERN GA/SC...WHERE LOW LEVEL LAPSE RATES BECOME QUITE STEEP. OVERALL MLCAPES WILL REMAIN MARGINAL WITH SURFACE DEW POINTS IN THE LOWER 60S. HOWEVER...MLCAPE WILL BE SUFFICIENT FOR SCATTERED THUNDERSTORMS AS LARGE SCALE ASCENT SPREADS EWD TOWARDS THE CAROLINAS TODAY. GIVEN MODEST WLY FLOW ALOFT AND STEEP LOW LEVEL LAPSE RATES...ISOLATED WIND DAMAGE AND HAIL ARE EXPECTED TO ACCOMPANY STRONGER CORES/LINES INTO THE EARLY EVENING. ..EVANS.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 16:35:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 12:35:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051629 SWODY1 SPC AC 051628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT FRI MAY 05 2006 VALID 051630Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS SW TX.... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK...FROM ERN NM TO SRN LA.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FOR PARTS OF GA/SC/NC.... ...SW/CENTRAL TX AREA THIS AFTERNOON INTO TONIGHT... THE PRIMARY SURFACE BAROCLINIC ZONE EXTENDS FROM ROUGHLY MAF TO ACT AS OF MID MORNING...WITH A SEPARATE CONVECTIVE OUTFLOW BOUNDARY FARTHER S ACROSS THE MIDDLE TX COAST. LOW-MID 60S BOUNDARY LAYER DEWPOINTS ARE SPREADING NWWD ALONG THE RIO GRANDE VALLEY TOWARD SW TX /S OF THE FRONT/...WHILE A PRONOUNCED MID LEVEL TROUGH IS MOVING EWD FROM SRN AZ TO SRN NM. MID-UPPER LEVEL FLOW WILL INCREASE OVER W TX IN ADVANCE OF THIS SYSTEM THROUGH THE AFTERNOON...WHILE CLOUD BREAKS S OF THE FRONT ALLOW SUBSTANTIAL SURFACE HEATING/DESTABILIZATION. MODIFIED 12Z SOUNDINGS...AND SHORT TERM MODEL FORECASTS...SUGGEST THE LIKELIHOOD OF 2000-3000 J/KG MLCAPE ALONG AND S OF THE FRONT THIS AFTERNOON FROM SW INTO CENTRAL TX. ADDITIONALLY...FORECAST HODOGRAPHS APPEAR SUPPORTIVE OF SUPERCELLS WITH EFFECTIVE SRH AND BULK SHEAR OF 150-250 M2/S2 AND AOA 50 KT...RESPECTIVELY. EXPECT SCATTERED SEVERE STORMS TO DEVELOP BY MID-LATE AFTERNOON INVOF THE SURFACE FRONT ALONG AN AXIS FROM CNM-MAF-SJT...WITH CONVECTION INCREASING IN COVERAGE AND SPREADING EWD/ESEWD INTO CENTRAL TX THIS EVENING. THE STRONG VERTICAL SHEAR AND STEEP MID LEVEL LAPSE RATES WILL SUPPORT A THREAT FOR VERY LARGE HAIL WITH THE SUPERCELLS...ALONG WITH A FEW TORNADOES WHERE LOW-LEVEL MOISTURE/SHEAR ARE MAXIMIZED FOR STORMS MOVING ALONG THE SURFACE BOUNDARY. LATER THIS EVENING...CONVECTION MAY GROW UPSCALE INTO ONE OR MORE MCS/S...WITH AN INCREASING THREAT FOR DAMAGING WINDS. ...SRN LA AREA THIS AFTERNOON... THUNDERSTORMS WILL LIKELY INCREASE IN COVERAGE/INTENSITY THIS AFTERNOON ALONG OUTFLOW BOUNDARIES ACROSS S CENTRAL/SE LA. MLCAPE VALUES NEAR 2000 J/KG WILL SUPPORT A THREAT FOR DAMAGING DOWNBURST WINDS AND LARGE HAIL WITH THE MORE INTENSE STORMS THIS AFTERNOON. ...GA/SC AREA THIS AFTERNOON... AN MCV OVER NRN AL WILL MOVE EWD OVER GA/SC THIS AFTERNOON/EVENING AS A COLD FRONT DRIFTS SEWD ACROSS THIS SAME REGION. THOUGH LOW-LEVEL MOISTURE AND MID LEVEL LAPSE RATES APPEAR MARGINAL FOR SEVERE STORMS ACROSS GA/SC...STEEP LOW-LEVEL LAPSE RATES AND A BELT OF 30-40 KT FLOW S OF THE AL MCV MAY SUPPORT A FEW STRONG/DAMAGING GUSTS WITH MULTICELL CLUSTERS THIS AFTERNOON. A MARGINAL SEVERE HAIL THREAT WILL ALSO ACCOMPANY THE STRONGER STORMS. ..THOMPSON/CROSBIE.. 05/05/2006  From swody1 at goshenarc.org Fri May 5 19:49:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 15:49:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051944 SWODY1 SPC AC 051943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT FRI MAY 05 2006 VALID 052000Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER FAR SERN NM SEWD ACROSS THE TX PERMIAN BASIN AND CONCHO VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT FROM ERN NM EWD INTO CNTRL AND SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER ERN GA AND MUCH OF SC... ...ERN NM AND TX... EARLY AFTERNOON MESOANALYSIS INDICATED PRIMARY SURFACE BOUNDARY FROM SERN NM ESEWD INTO CNTRL TX INTO W-CNTRL LA WITH ATTENDANT DRY LINE BECOMING BETTER DEFINED FROM WEAK TRIPLE POINT LOW NEAR CNM SSEWD INTO THE TX BIG BEND REGION. WHILE LOW CLOUDS HAVE PERSISTED N OF THIS BOUNDARY OVER THE TX S PLAINS...COMPARATIVELY STRONGER DIABATIC HEATING COUPLED WITH DEWPOINTS IN THE UPPER 50S/LOWER 60S AND STEEP LAPSE RATES ARE CONTRIBUTING TO MODERATE INSTABILITY /REF. 18Z MAF SOUNDING/ ALONG AND S OF BOUNDARY WITH MLCAPES OF 1000-2000 J/KG. SATELLITE IMAGERY AND REGIONAL RADAR DATA SHOW TSTMS INCREASING IN COVERAGE AND INTENSITY OVER THE HIGHER TERRAIN OF NERN AND E-CNTRL NM AS LEADING EDGE OF STRONGER FORCING ASSOCIATED WITH SRN ROCKIES MID-LEVEL TROUGH HAS OVERSPREAD WRN EXTENSION OF INSTABILITY AXIS. EXPECT THESE TSTMS TO INCREASE IN COVERAGE THIS AFTERNOON INTO EVENING EWD INTO THE TX PNHDL AND S PLAINS AS THIS FORCING FOR ASCENT CONTINUES TO SHIFT EWD. THE MAJORITY OF THESE STORMS WILL LIKELY REMAIN ELEVATED...THOUGH SUPERCELLS CAPABLE OF LARGE HAIL WILL BE POSSIBLE OWING TO THE STEEP MID-LEVEL LAPSE RATES...MODERATE ELEVATED INSTABILITY AND 40-50 KTS OF EFFECTIVE BULK SHEAR. MORE INTENSE SURFACE-BASED STORM DEVELOPMENT IS ANTICIPATED BY MID TO LATE AFTERNOON NEARER TO SURFACE BOUNDARY OVER SERN NM INTO THE PERMIAN BASIN WHERE SUPERCELLS APPEAR LIKELY. WHILE LARGE HAIL /SOME SIGNIFICANT/ WILL BE THE PRIMARY SEVERE WEATHER THREAT...TORNADOES WILL BE POSSIBLE WITH ANY MATURE SUPERCELLS WHICH CAN FAVORABLY INTERACT WITH SYNOPTIC OR ANY SMALLER-SCALE BOUNDARIES WHERE LOW-LEVEL SHEAR WILL BE ENHANCED. ADDITIONAL STORM DEVELOPMENT POSSIBLE THIS AFTERNOON FARTHER DOWNSTREAM ALONG SYNOPTIC FRONT OVER THE CONCHO VALLEY AND ALONG DRY LINE OR OROGRAPHICALLY FAVORED AREAS OF SWRN TX. SAME GENERAL LARGE-SCALE REGIME WILL SUPPORT SUPERCELLS IN THESE AREAS AS WELL. UPSCALE GROWTH OF ANY MORE DISCRETE STORMS OVER WRN OR SWRN TX INTO A MCS WILL LIKELY OCCUR OVERNIGHT WITH A THREAT OF HIGH WINDS AND HAIL SPREADING EWD INTO CNTRL TX. ...SRN LA... CLUSTERS OF STRONG TSTMS ARE IN PROGRESS THIS AFTERNOON OVER SRN LA IN ADVANCE OF WEAK MID-LEVEL IMPULSE SHIFTING SEWD THROUGH CNTRL LA. AMBIENT AIR MASS REMAINS MOIST AND MODERATELY UNSTABLE...WHICH SHOULD SUPPORT A FEW VIGOROUS UPDRAFTS CAPABLE OF MARGINALLY SEVERE WIND AND HAIL. ...ERN GA INTO CNTRL/ERN NC... REGIONAL RADAR IMAGERY INDICATES A BROKEN ARC OF TSTMS FROM NEAR AHN SWD INTO THE ERN FL PNHDL MOVING EWD AT 20-25 KTS. FORCING FOR ASCENT AHEAD OF CONVECTIVELY-INDUCED VORTICITY MAXIMUM OVER NWRN GA COUPLED WITH A MOIST AND MODERATELY UNSTABLE AIR MASS WILL LIKELY MAINTAIN THESE TSTMS EWD ACROSS THE REMAINDER OF GA INTO SC THIS AFTERNOON AND EVENING. WHILE REGIONAL VWPS INDICATE THAT VERTICAL SHEAR REMAINS QUITE WEAK...DATA NEAR MCV SUGGEST SOME LOCAL INCREASE IN MID AND HIGH-LEVEL WIND FIELDS WHICH MAY SUPPORT SOME STORM ORGANIZATION WITH A THREAT OF LOCALLY DAMAGING WINDS AND SOME SEVERE HAIL. ..MEAD.. 05/05/2006  From swody1 at goshenarc.org Sat May 6 01:03:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 05 May 2006 21:03:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060100 SWODY1 SPC AC 060058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT FRI MAY 05 2006 VALID 060100Z - 061200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF W CNTRL TEXAS.... ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS A LARGE PART OF THE SRN PLAINS.... NORTHERN BRANCH TROUGH OVER EASTERN CANADA AND THE NORTHEASTERN U.S. HAS AMPLIFIED IN RESPONSE TO EMBEDDED DIGGING SHORT WAVE IMPULSE...WHICH WILL TURN EASTWARD ACROSS THE GREAT LAKES REGION OVERNIGHT. AS THIS 0CCURS...AND UPSTREAM SHORT WAVE TROUGH PROGRESSES INTO THE PACIFIC COAST ON NOSE OF SEASONABLY STRONG NORTHERN PACIFIC JET...SOUTHERN BRANCH TROUGH CONTINUES TO BREAK DOWN AND SHIFT EASTWARD OUT OF THE INTERMOUNTAIN WEST. ONE SIGNIFICANT SHORT WAVE IMPULSE ASSOCIATED WITH THE LATTER FEATURE IS ALREADY SUPPORTING WIDESPREAD CONVECTIVE DEVELOPMENT ACROSS THE SOUTH CENTRAL HIGH PLAINS. UPSTREAM IMPULSE IS QUICKLY ON ITS HEELS...AND PROGGED EAST OF THE FOUR CORNERS INTO THE SOUTHERN HIGH PLAINS BY 12Z SATURDAY. THIS WILL CONTRIBUTE TO FURTHER CONVECTIVE DEVELOPMENT ACROSS THE SOUTHERN PLAINS OVERNIGHT. ...SOUTHERN PLAINS... WHILE BAROCLINIC ZONE ASSOCIATED WITH THE SOUTHERN STREAM EXTENDS ACROSS UPPER TEXAS COASTAL AREAS THROUGH THE HILL COUNTRY INTO THE RIO GRANDE VALLEY...INHIBITION HAS LIMITED CONVECTIVE DEVELOPMENT ACROSS THIS REGION SO FAR. THE SAME GENERALLY APPLIES FOR THE DRY LINE EAST OF THE BIG BEND INTO SOUTHEAST NEW MEXICO. THE PRIMARY FORCING FOR CONVECTION HAS BEEN CONFINED TO A WARM ADVECTION REGIME ALONG A BAROCLINIC ZONE ASSOCIATED WITH THE NORTHERN STREAM...ACROSS THE TEXAS SOUTH PLAINS. THIS IS JUST NORTH OF WHERE STRONG HEATING OCCURRED EAST OF DRY LINE...CONTRIBUTING TO MIXED LAYER CAPE AROUND 2000 J/KG IMMEDIATELY NEAR SURFACE FRONT...AND MOST UNSTABLE CAPE IN EXCESS OF 2000 IN A NARROW CORRIDOR TO THE NORTH. MULTIPLE SUPERCELLS ARE ONGOING ALONG THE BOUNDARY ACROSS THE SOUTH PLAINS INTO PARTS OF NORTHWEST TEXAS...AND A CONSOLIDATION INTO A LARGER CONVECTIVE CLUSTER APPEARS UNDERWAY NEAR/WEST OF ABILENE. EASTERLY COMPONENT TO LOW-LEVEL FLOW BENEATH 30 TO 50 KT WESTERLY MID-LEVEL FLOW IS CONTRIBUTING TO VERY STRONG SHEAR SUPPORTIVE OF CONTINUING EVOLUTION OF A SEVERE MESOSCALE CONVECTIVE SYSTEM...WITH POTENTIAL FOR STRONG DAMAGING WINDS. HIGHEST WIND DAMAGE POTENTIAL APPEARS POSSIBLE ACROSS THE ABILENE AREA THROUGH 02-03Z...BEFORE THREAT BEGINS TO DIMINISH IN MORE STABLE OR STABILIZING LOW-LEVEL ENVIRONMENT ALONG FRONT FARTHER TO THE EAST...ACROSS AREAS NEAR/SOUTH OF DALLAS. INITIAL CLUSTER MAY DISSIPATE OVERNIGHT...BUT WITH THE APPROACH OF THE NEXT IMPULSE...INCREASING LOW/MID-LEVEL WARM ADVECTION MAY SUPPORT ADDITIONAL STRONG/SEVERE STORMS WITH PRIMARILY LARGE HAIL POTENTIAL NORTH/WEST OF THE SAN ANTONIO/HOUSTON AREAS RESPECTIVELY. ...SOUTH ATLANTIC COAST STATES... CONVECTION HAS BECOME FAIRLY WIDESPREAD FROM GEORGIA THROUGH THE CAROLINAS...SUPPORTED BY WEAK SOUTHERN BRANCH TROUGH. HOWEVER... INTENSITY OF ACTIVITY SHOULD CONTINUE TO DIMINISH AS ENVIRONMENT STABILIZES WITH LOSS OF DAYTIME HEATING. ..KERR.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 05:58:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 01:58:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060556 SWODY1 SPC AC 060554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT SAT MAY 06 2006 VALID 061200Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS PARTS OF THE SRN PLAINS INTO THE WRN/CNTRL GULF COAST.... STRONG ZONAL NORTH PACIFIC JET CONTINUES TO PROPAGATE TOWARD THE PACIFIC NORTHWEST COAST. ASSOCIATED SHORT WAVE TROUGH ON NOSE OF THIS FEATURE IS SPLITTING IN DISTINCT NORTHERN/SOUTHERN BRANCHES OF STRONGER FLOW EXTENDING INLAND DOWNSTREAM...WITH STRONGER NORTHERN IMPULSE PROGGED EAST OF THE CANADIAN/NORTHERN U.S. ROCKIES BY 12Z SUNDAY. WEAKER SOUTHERN IMPULSE IS FORECAST TO DIG INTO THE LOWER COLORADO VALLEY/NORTHERN BAJA...AND LAST IN SERIES OF SHORT WAVES...ASSOCIATED WITH WHAT IS LEFT OF LARGER SCALE SOUTHERN BRANCH TROUGH...IS PROGGED TO ACCELERATE EAST NORTHEAST OF THE SOUTHERN HIGH PLAINS AND RED RIVER VALLEY. FARTHER EAST...AS MOST SIGNIFICANT SHORT WAVE EMBEDDED WITHIN NORTHERN BRANCH TROUGH LIFTS FROM THE LOWER LAKES THROUGH THE CANADIAN MARITIMES/NORTH ATLANTIC COAST...WEAK TROUGH IN THE SOUTHERN BRANCH WILL FINALLY PROGRESS EAST OF SOUTH ATLANTIC COASTAL AREAS. FORCING ASSOCIATED WITH VARIOUS SHORT WAVE TROUGHS AND SEASONABLE INSTABILITY WILL SUPPORT SCATTERED THUNDERSTORM ACTIVITY ACROSS THE NATION TODAY. HOWEVER...LOW-LEVEL COOLING/DRYING EAST OF THE ROCKIES...PRIMARILY IN ASSOCIATION WITH AMPLIFIED NORTHERN BRANCH TROUGH...BUT ALSO IN PART DUE TO EXTENSIVE CONVECTIVE DEVELOPMENT ASSOCIATED WITH THE SOUTHERN STREAM...HAS NOW SUPPRESSED SIGNIFICANT MOISTURE TO SOUTHERN/EASTERN TEXAS AND THE CENTRAL GULF COAST. ...SOUTHERN PLAINS/LOWER MISSISSIPPI VALLEY... ONE OR MORE CLUSTERS OF STORMS IS EXPECTED TO BE ONGOING AT THE BEGINNING OF THE FORECAST PERIOD ACROSS PARTS OF SOUTHEAST TEXAS/ LOUISIANA. IT SEEMS MOST PROBABLE THAT CONVECTION NEAR/EAST OF CONVECTIVELY INDUCED/ENHANCED CYCLONIC VORTICITY CENTER WILL BE WEAKENING NEAR THE SABINE RIVER. HOWEVER...VIGOROUS STORMS MAY PERSIST IN ASSOCIATION WITH LOW-LEVEL CONVERGENCE/WARM ADVECTION ALONG OUTFLOW BOUNDARY PROGRESSING TOWARD MID/UPPER TEXAS COASTAL AREAS. THIS MAY PROVIDE THE PRIMARY SEVERE THREAT THIS FORECAST PERIOD AS IT PROGRESSES ACROSS HOUSTON AND ADJACENT AREAS BY MID DAY. REDEVELOPMENT IN WAKE OF THIS ACTIVITY IS UNCERTAIN. SIGNIFICANT STABILIZATION OF LOWER LEVELS MAY OCCUR ACROSS A LARGE PORTION OF CENTRAL/EASTERN TEXAS. ADDITIONALLY...MID-LEVEL SUBSIDENCE/WARMING SOUTH OF 50 KT CYCLONIC 500 MB JET PROGGED ACROSS NORTHERN TEXAS DURING THE DAY WILL BE INHIBITIVE. HOWEVER...BOUNDARY LAYER WILL REMAIN MOIST AND POTENTIALLY MODERATELY UNSTABLE NEAR INTERSECTION OF STALLING OUTFLOW BOUNDARY AND DRY LINE...NEAR/NORTH OF SAN ANTONIO BY LATE AFTERNOON. THIS COULD SERVE AS THE FOCUS FOR AT LEAST ISOLATED NEW CONVECTIVE DEVELOPMENT. IF THIS OCCURS...GENERALLY LIGHT BUT VEERING WINDS WITH HEIGHT BENEATH MODERATE WESTERLY MID-LEVEL FLOW WILL BE SUFFICIENT FOR SUPERCELLS...PRIMARILY WITH LARGE HAIL/GUSTY WINDS. OTHER STORMS COULD DEVELOP OFF THE HIGHER TERRAIN OF MEXICO THROUGH THE LOWER RIO GRANDE VALLEY BY EARLY EVENING. THE GFS...MORE SO THAN THE NAM...SUGGESTS THAT FORCING ASSOCIATED WITH THE SOUTHERN STREAM IMPULSE COULD SUPPORT ADDITIONAL SIGNIFICANT CONVECTIVE DEVELOPMENT NEAR LINGERING SYNOPTIC FRONTAL ZONE ACROSS NORTH CENTRAL/NORTHEAST TEXAS LATE THIS AFTERNOON. BOUNDARY LAYER RECOVERY NORTH OF COMPOSITE CONVECTIVE OUTFLOW IS UNCERTAIN...BUT THIS ACTIVITY COULD AT LEAST POSE A RISK FOR LARGE HAIL BEFORE WEAKENING ACROSS THE LOWER MISSISSIPPI VALLEY THIS EVENING. ..KERR/JEWELL.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 12:41:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 08:41:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061238 SWODY1 SPC AC 061237 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0737 AM CDT SAT MAY 06 2006 VALID 061300Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CENTRAL/SRN TX INTO SRN LA... ...UPPER TX COAST ACROSS SRN LA... LINEAR MCS WAS MOVING INTO THE SABINE RIVER VALLEY WITH MAIN IMPETUS BOWING OFF THE SERN TX COAST AT 12Z. THUS...SLOWER MOVING N-S ORIENTED AXIS OF STRONG STORMS WILL SPREAD EWD ACROSS WRN LA THIS MORNING AS WEAK SHORTWAVE TROUGH SHIFTS TOWARD THE LOWER MS RIVER VALLEY. COMPOSITE OUTFLOW BOUNDARY/COASTAL FRONT EXTENDED FROM THE MS RIVER DELTA WWD INTO LINEAR MCS JUST NORTH OF THE UPPER TX COAST EARLY THIS MORNING. A VERY MOIST BOUNDARY LAYER REMAINS SOUTH OF THIS FRONT WHICH WILL LIKELY LIFT SLOWLY NWD AS PRESSURE FALLS AND SLY LOW LEVEL WINDS INCREASE ACROSS SRN LA TODAY. MID LEVEL LAPSE RATES REMAIN QUITE STEEP AND WILL SUPPORT A VERY UNSTABLE AIR MASS BY THE LATE MORNING FROM PORTIONS OF CENTRAL LA EWD TO JUST OFF THE CENTRAL GULF COAST. MID LEVEL WINDS ASSOCIATED WITH APPROACHING MID/UPPER LEVEL TROUGH WILL REMAIN SUFFICIENT FOR 40-50 KT DEEP LAYER SHEAR ACROSS THIS REGION. THEREFORE...EXPECT AN INCREASE IN SEVERE THREAT DURING THE MID TO LATE MORNING INTO PORTIONS OF CENTRAL LA AS HEATING COMMENCES AND COASTAL FRONT SHIFTS SLOWLY NWD. THOUGH OVERALL MODE MAY REMAIN LINEAR AS N-S ORIENTED OUTFLOW BOUNDARY SURGES EWD TODAY...SHEAR WILL BE SUFFICIENT FOR SUPERCELLS ESPECIALLY IF ACTIVITY DEVELOPS AHEAD OF ONGOING CONVECTIVE LINE OR LINE BECOMES MORE BROKEN. MESO LOW MAY FORM ALONG INTERSECTION OF OUTFLOW BOUNDARY AND E-W ORIENTED COASTAL FRONT SUPPORTING A THREAT OF TORNADOES GIVEN AMOUNT OF SHEAR. EASTERN AND NORTHERN EXTENT OF SUBSEQUENT SEVERE THREAT WILL BE MODULATED BY MORE LIMITED INSTABILITY ACROSS NRN LA AND EAST OF THE MS RIVER. ...SWRN TX TO THE MIDDLE TX COAST/DEEP SOUTH TX... OUTFLOW BOUNDARY WILL LIKELY SLOW ITS SWD MOTION FROM THE MIDDLE TX COAST TOWARDS THE BIG BEND REGION AND LIKELY LIFT SLOWLY NWD OR ERODE THIS AFTERNOON. AIR MASS REMAINS QUITE MOIST AND CONDITIONALLY VERY UNSTABLE FROM DEEP SOUTH TX INTO RIO GRANDE VALLEY SOUTH OF THIS OUTFLOW WITH SFC DEW POINTS IN THE LOWER 70S BELOW 8+ C/KM MID LEVEL LAPSE RATES. IN ADDITION...MODEST WNWLY FLOW ALOFT WILL SUPPORT 45-55 KT EFFECTIVE SHEAR THROUGH THE PERIOD. GIVEN STEEPNESS OF MID LEVEL LAPSE RATES AND AMOUNT OF MUCAPE...ELEVATED SEVERE THUNDERSTORMS INCLUDING SUPERCELLS MAY PERSIST THIS MORNING WITH A THREAT OF LARGE HAIL FROM THE TX HILL COUNTRY INTO THE COASTAL PLAIN. MORE VIGOROUS DEVELOPMENT IN THE FORM OF SUPERCELLS IS EXPECTED TO BE DRIVEN BY STRONG HEATING AND CONVERGENCE ALONG SURFACE OUTFLOW BOUNDARIES/COLD FRONT AND LEE TROUGH/DRY LINE FROM THE EDWARDS PLATEAU/BIG BEND REGION INTO THE LOWER RIO GRANDE VALLEY BY 20Z. GIVEN EXPECTED SHEAR...EXTREME INSTABILITY WILL SUPPORT A FEW INTENSE SUPERCELLS AGAIN LATE TODAY AND THIS EVENING SPREADING ESEWD. AS HAS BEEN THE CASE THE PAST FEW DAYS...VERY LARGE HAIL AND POSSIBLY A FEW TORNADOES WILL BE PRIMARY SEVERE THREATS. HOWEVER...AN INCREASED WIND THREAT MAY PERSIST THROUGH THE EVENING/OVERNIGHT AS ONE OR MORE MCSS EVOLVE. ..EVANS.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 16:36:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 12:36:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061634 SWODY1 SPC AC 061632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT SAT MAY 06 2006 VALID 061630Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS CENTRAL AND S TX.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS SRN LA.... ...TX/LA AREA... THE REMNANTS OF AN OVERNIGHT MCS...WITH A PROBABLE EMBEDDED MCV...ARE MOVING EWD ACROSS SW LA. E OF THE OUTFLOW ASSOCIATED WITH THIS CONVECTION...AN E-W ORIENTED BAROCLINIC ZONE EXTENDS ACROSS SE LA INTO THE EXTREME NE GULF OF MEXICO. THIS BOUNDARY MAY LIFT SLOWLY NWD IN ADVANCE OF THE LA MCS...WHICH WILL ALLOW A VERY MOIST AND MODERATELY UNSTABLE AIR MASS TO SPREAD INLAND ACROSS SRN LA. WHILE VERTICAL SHEAR WILL NOT BE PARTICULARLY STRONG IN THE WARM SECTOR...THERE WILL BE SOME ENHANCEMENT OF THE MID LEVEL FLOW ON THE SRN PERIPHERY OF THE MCV. EXPECT THE THREAT FOR AT LEAST ISOLATED DAMAGING WINDS AND LARGE HAIL TO PERSIST WITH LINE SEGMENTS AND POTENTIALLY SUPERCELLS E OF THE ONGOING ACTIVITY. THE MORE PRONOUNCED SUPERCELL THREAT WILL BE ALONG THE SURFACE BOUNDARY WHERE THE STRONGER LOW-LEVEL SHEAR AND INSTABILITY WILL COINCIDE...AND AN ISOLATED TORNADO OR TWO WILL BE POSSIBLE. ...CENTRAL/S TX AREA... OUTFLOW FROM THE MCS OVER LA/NW GULF CONTINUES TO MOVE SWWD TO S TX AND THE RIO GRANDE VALLEY. RESIDUAL INSTABILITY AND WAA ABOVE THE COLD POOL COULD MAINTAIN THE THREAT FOR STRONG/ISOLATED SEVERE STORMS INTO EARLY AFTERNOON NEAR THE MIDDLE TX COAST. THE MCS HAS STABILIZED MUCH OF E/SE TX...WHICH SHOULD LIMIT THE THREAT FOR ADDITIONAL SEVERE STORMS THIS AFTERNOON ACROSS EXTREME E/SE TX. FARTHER W...SOME LOW-LEVEL DESTABILIZATION WILL TAKE PLACE ACROSS CENTRAL TX WHERE THE CLOUD DEBRIS FROM THE MCS HAS CLEARED. THE MORE PROBABLE AREAS FOR ADDITIONAL DEVELOPMENT THIS AFTERNOON WILL BE ACROSS CENTRAL TX ALONG THE SE MOVING COLD FRONT /NEAR THE SRN FRINGE OF A SHORTWAVE TROUGH MOVING EWD FROM W TX/...AND ALONG THE OUTFLOW BOUNDARY ACROSS DEEP S TX AND THE RIO GRANDE VALLEY WHERE LIFT MAY BE SUFFICIENT TO OVERCOME A SUBSTANTIAL CAP. VERTICAL SHEAR AND INSTABILITY WILL BE SUFFICIENT FOR SUPERCELLS IN BOTH AREAS...WITH LARGE HAIL AND DAMAGING WINDS EXPECTED TO BE THE PRIMARY SEVERE THREATS. ..THOMPSON/CROSBIE.. 05/06/2006  From swody1 at goshenarc.org Sat May 6 19:52:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 15:52:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 061950 SWODY1 SPC AC 061949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SAT MAY 06 2006 VALID 062000Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER PORTIONS OF CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER THE CNTRL GULF COAST... ...CNTRL/SRN TX... COMPLEX SURFACE PATTERN EXISTS THIS AFTERNOON OWING TO MULTIPLE MESOSCALE BOUNDARIES REMNANT FROM EARLIER CONVECTION. MESOANALYSIS INDICATES WEAK SURFACE LOW NEAR JCT WITH ATTENDANT COLD FRONT EXTENDING SWWD TO W OF DRT. THIS BOUNDARY THEN STRETCHES NEWD INTO SERN OK...WITH ANOTHER BAROCLINIC ZONE EWD FROM THIS LOW INTO E-CNTRL TX NEAR LFK. HEATING AND FRONTAL CONVERGENCE COUPLED WITH GLANCING INFLUENCE OF VORTICITY/SPEED MAXIMUM TRANSLATING THROUGH NWRN TX ARE CONTRIBUTING TO SURFACE-BASED TSTM DEVELOPMENT ALONG FRONT FROM NEAR JCT SWWD TO NW OF DRT. CURRENT SAN ANTONIO VWP SHOWS SLY SURFACE WINDS VEERING TO WLY AT 50 KTS IN THE 5-6 KM AGL. WHILE MID-LEVEL LAPSE RATES ARE NOT PARTICULARLY STEEP...THE MODERATELY STRONG VERTICAL SHEAR AND MLCAPES OF 1000-2000 J/KG WILL SUPPORT ORGANIZED SEVERE STORMS...INCLUDING SUPERCELLS CAPABLE OF LOCALLY DAMAGING WINDS AND LARGE HAIL. STORMS WILL LIKELY INCREASE IN COVERAGE ALONG FRONT OVER THE EDWARDS PLATEAU INTO THE HILL COUNTRY WITH THE WIND AND HAIL THREAT SPREADING SEWD TOWARD THE COAST OVERNIGHT. ...CNTRL GULF COAST... MCS OVER THE LOWER MS VALLEY CONTINUES TO DECAY THIS AFTERNOON OVER SWRN MS INTO CNTRL LA. HOWEVER...ADDITIONAL STORMS HAVE RECENTLY DEVELOPED FARTHER TO THE E OF FAR SERN MS...NEAR WEAK FRONTAL BOUNDARY RETREATING NWD. VWP FROM THE NEW ORLEANS AREA INDICATES THAT WIND FIELDS ARE NOT PARTICULARLY STRONG...THOUGH THERE IS SOME VEERING WITH HEIGHT WHICH IS CONTRIBUTING TO 40-45 KTS OF DEEP-LAYER SHEAR. REGIONAL RADAR LOOP SHOWS THAT MCV WHICH SUPPORTED THIS MORNING/S MCS ORGANIZATION FARTHER TO THE W OVER THE SABINE VALLEY IS LIFTING MORE NEWD INTO CNTRL MS. THEREFORE...ADDITIONAL STORM DEVELOPMENT WILL HAVE TO BE DRIVEN BY WEAK LOW-LEVEL WAA AND CONVERGENCE ALONG PRE-EXISTING BOUNDARIES. STRONGEST STORMS WILL REMAIN CAPABLE OF LOCALLY DAMAGING WINDS AND PERHAPS AN ISOLATED TORNADO OR TWO INTO THIS EVENING. ..MEAD.. 05/06/2006  From swody1 at goshenarc.org Sun May 7 01:06:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 06 May 2006 21:06:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070104 SWODY1 SPC AC 070102 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0802 PM CDT SAT MAY 06 2006 VALID 070100Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE HILL COUNTRY AND SEWD TOWARD THE MIDDLE TX COAST... ...CENTRAL AND ERN TX ACROSS THE GULF COAST... LIMITED SEVERE THREAT WILL PERSIST FROM TX ACROSS THE GULF COAST REGION OVERNIGHT...WHERE SUFFICIENT INSTABILITY AND MARGINAL SHEAR IS EVIDENT. GREATEST THREAT APPEARS TO EXIST FROM THE TX HILL COUNTRY ESEWD TOWARD THE COAST...WHERE 1000 T0 2000 J/KG MEAN-LAYER CAPE IS INDICATED. WITH LOW-LEVEL ESELYS BENEATH MODERATE MID-LEVEL WNWLYS...SHEAR SUFFICIENT FOR ORGANIZED/SUPERCELL STORMS EXISTS. THOUGH ALL MODEL GUIDANCE SUGGESTS A WEAKENING TREND WITH TIME ACROSS THIS REGION AS UPPER SUPPORT SLIDES BY TO THE N...WILL CONTINUE A SLIGHT RISK FORECAST -- AT LEAST INTO THIS EVENING. FURTHER E...STORMS ACROSS SRN MS/SRN AL ASSOCIATED WITH MCV REMNANTS HAVE SHOWN A WEAKENING TREND WITH TIME. THOUGH SOME THREAT EXISTS FOR A STRONGER STORM OR TWO TO PERSIST THROUGH THIS EVENING...OVERALL THREAT SHOULD CONTINUE TO WANE. ..GOSS.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 06:05:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 02:05:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070602 SWODY1 SPC AC 070600 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT SUN MAY 07 2006 VALID 071200Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL AND SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SERN CONUS... ...SYNOPSIS... LOW-AMPLITUDE MID-LEVEL SHORT-WAVE TROUGH IS FORECAST TO MOVE ACROSS THE SOUTHEAST THIS PERIOD...WHILE A SECOND TROUGH -- EXTENDING SWD ACROSS THE ERN ROCKIES -- MOVES EWD ACROSS THE PLAINS. AT THE SURFACE...W-E FRONT IS RETREATING NWD ACROSS THE CENTRAL GULF COAST STATES AHEAD OF UPPER TROUGH. A WEAK LOW SHOULD EVOLVE ALONG THIS BOUNDARY OVER NRN AL EARLY IN THE PERIOD...WITH A WEAK TRAILING COLD FRONT EXPECTED MOVE ACROSS THE SOUTHEAST THROUGH THE PERIOD. A WEAK COLD FRONT WILL ALSO MOVE ACROSS THE DAKOTAS...WHILE FURTHER S A LEE TROUGH MOVES ACROSS THE CENTRAL/SRN HIGH PLAINS. ...THE PLAINS... SHORT-WAVE RIDGING AND ASSOCIATED CAPPING INVERSION IS INITIALLY EXPECTED ACROSS THE PLAINS...WHICH SHOULD SUPPRESS ANY POTENTIAL FOR CONVECTION INTO THE AFTERNOON. NONETHELESS...LIMITED MOISTURE COMBINED WITH DAYTIME HEATING WILL ALLOW SOME DESTABILIZATION /1000 TO 1500 J/KG MEAN-LAYER CAPE/ TO OCCUR. AS UPPER TROUGH AND ASSOCIATED LOW-LEVEL FRONT/TROUGH MOVE INTO THE PLAINS...EXPECT ISOLATED STORMS TO DEVELOP BY LATE AFTERNOON -- FROM ND SWD INTO NERN NM/THE TX PANHANDLE. DEEP-LAYER WIND FIELD IS FORECAST TO BE SOMEWHAT WEAK FROM KS NWD...BUT SHEAR MAY BE SUFFICIENT FOR SOME MID-LEVEL ROTATION WITH STRONGER STORMS. WILL MAINTAIN THE SLIGHT RISK AREA OVER THE CENTRAL AND SRN HIGH PLAINS -- AS MODELS ARE IN GENERAL AGREEMENT THAT GREATEST CONVECTIVE COVERAGE -- AND THUS A RELATIVELY HIGHER COVERAGE OF SEVERE WEATHER -- SHOULD OCCUR OVER THIS REGION. FURTHER S INTO TX...SHEAR AND INSTABILITY ARE BOTH FORECAST TO BE STRONGER...BUT MORE PERSISTENT SHORT-WAVE RIDGING/LOW-LEVEL CAPPING SHOULD LIMIT STORM COVERAGE WITH SWD EXTENT. OVERNIGHT...40 KT SLY LOW-LEVEL JET IS FORECAST TO DEVELOP OVER CENTRAL TX/CENTRAL OK. THIS SHOULD SUPPORT AN INCREASE IN CONVECTION...WITH THE POTENTIAL FOR ONE OR MORE MCS TO EVOLVE AND MOVE SEWD ACROSS PARTS OF OK/TX. THOUGH LOSS OF HEATING/DECREASING INSTABILITY SUGGESTS A SLOW DECREASE IN SEVERE THREAT...LOCALLY-DAMAGING WINDS/HAIL COULD PERSIST INTO THE OVERNIGHT HOURS SHOULD MESOSCALE CONVECTIVE ORGANIZATION OCCUR. ...THE SOUTHEAST... SCATTERED SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING ACROSS MUCH OF THE REGION AT THE START OF THE PERIOD...AHEAD OF COLD FRONT AND ASSOCIATED SHORT-WAVE TROUGH. THE ONGOING/PERSISTENT PRECIPITATION SHOULD LIMIT POTENTIAL FOR DESTABILIZATION ACROSS MUCH OF THE REGION. ADDITIONALLY...VEERED/WLY LOW-LEVEL FLOW IS ANTICIPATED AHEAD OF FRONT...WHICH SHOULD LIMIT CONVERGENCE ALONG BOUNDARY. NONETHELESS...FAIRLY STRONG /AROUND 50 KT/ WLY MID-LEVEL JET IS FORECAST ALONG SRN FRINGE OF TROUGH...WHICH WILL CONTRIBUTE TO DEEP-LAYER SHEAR SUFFICIENT FOR ORGANIZED STORMS. THEREFORE...WILL MAINTAIN A LARGE SLIGHT RISK AREA OVER THE SERN CONUS -- MAINLY FOR ISOLATED STRONGER STORMS DEVELOPING WITHIN POCKETS OF LOCALLY GREATER INSTABILITY. ..GOSS.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 12:52:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 08:52:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071250 SWODY1 SPC AC 071248 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 AM CDT SUN MAY 07 2006 VALID 071300Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL GULF COAST AND SOUTHEAST... ...THERE IS A SLGT RISK OF SVR TSTMS INTO THE CENTRAL AND SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER SWRN TX... ...LOWER MS RIVER VALLEY ACROSS THE SOUTHEAST... BOUNDARY LAYER REMAINS QUITE MOIST AHEAD OF SHORTWAVE TROUGH NOW PROGRESSING EWD ACROSS THE CENTRAL GULF COAST STATES THIS MORNING WITH SURFACE DEW POINTS IN THE MID/UPPER 60S. WITH HEATING THIS SHOULD BE SUFFICIENT FOR MODERATE INSTABILITY EAST OF WEAK SURFACE LOW AND ASSOCIATED COLD FRONT FORECAST TO SHIFT EWD FROM CENTRAL AL INTO GA/SC TODAY. CONVERGENCE AND DEEP ASCENT ARE EXPECTED TO SUPPORT WIDESPREAD THUNDERSTORMS ACROSS THIS REGION THROUGH THE DAY...WITH SEVERE THREAT INCREASING IN BOTH INTENSITY AND COVERAGE WITH HEATING THIS MORNING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR WILL BE SUFFICIENT /I.E. EFFECTIVE SHEAR AROUND 40 KT/ FOR SUPERCELLS AND SMALL LINES...WITH PRIMARY SEVERE THREATS OF DAMAGING WINDS AND LARGE HAIL. ...PLAINS STATES... NARROW AXIS OF SURFACE-BASED INSTABILITY WILL DEVELOP TODAY OVER THE PLAINS ALONG WRN PERIPHERY OF LARGE SURFACE ANTICYCLONE CENTERED OVER THE NORTHEAST. FROM PORTIONS OF WRN TX INTO THE CENTRAL/ERN DAKOTAS...SLY LOW LEVEL FLOW WILL BECOME FOCUSED AHEAD OF A SURFACE TROUGH/COLD FRONT ADVANCING EWD OUT OF THE WRN PLAINS. MODELS HAVE BEEN CONSISTENT FOR SEVERAL RUNS IN INITIATING THUNDERSTORMS ALONG THIS FEATURE FROM CENTRAL/ERN ND INTO FAR ERN CO/WRN KS AND THE OK/TX PANHANDLES BY THE LATE AFTERNOON. ACTIVITY WILL INCREASE AHEAD OF A FAST MOVING SHORTWAVE TROUGH NOW SPREADING ACROSS THE NRN/CENTRAL ROCKIES WITH ASSOCIATED 25-35 KT WLY H5 FLOW INCREASING DEEP LAYER SHEAR AND SUPPORTING ORGANIZED CONVECTION. THOUGH AIR MASS IS NOT FORECAST TO DESTABILIZE SIGNIFICANTLY...BOUNDARY LAYER MOISTURE IS EXPECTED TO BE SUFFICIENT FOR MODEST MLCAPE NWD INTO PORTIONS OF WRN KS/NEB...WITH WEAKER INSTABILITY AND A DIMINISHED SEVERE THREAT NWD INTO THE DAKOTAS. SUPERCELLS AND MULTICELL CLUSTERS/LINES WILL EVOLVE EWD OUT OF THE CENTRAL/SRN HIGH PLAINS WITH THREATS OF ISOLATED LARGE HAIL/DAMAGING WINDS. SEVERE THREAT EXPECTED TO DIMINISH AFTER DARK...THOUGH THUNDERSTORM CLUSTERS WILL CONTINUE EWD FOR MUCH OF THE NIGHT. EXCEPTION MAY BE INTO PORTIONS OF WRN OK/NWRN TX ALONG NOSE OF 40 KT SLY LLJ WHICH IS FORECAST TO DEVELOP THIS EVENING. INTENSE STORMS/CLUSTERS OVER THE OK/TX PANHANDLE REGION AND SWRN KS/SERN CO MAY EVOLVE INTO A MCS WITH A MORE PERSISTENT SEVERE THREAT LINGERING SEWD INTO THE RED RIVER VALLEY THROUGH THE LATE EVENING. ...SWRN TX... STRONG HEATING WILL PROVIDE A VERY WEAK CAP ALONG NWRN EDGE OF RICH GULF MOISTURE EXPECTED TO NOSE INTO SWRN TX THIS AFTERNOON. 12Z SOUNDING AT DRT INDICATED ABUNDANT LOW LEVEL MOISTURE ALONG WITH A WEAK CAP. THOUGH CAPPING SHOULD INCREASE UNDER WLY FLOW ALOFT AS EVIDENCED BY 20C H85 TEMPS AT ELP THIS MORNING...SURFACE HEATING THROUGH THE 80S SHOULD WEAKEN CAP SUFFICIENTLY FOR A THREAT OF VIGOROUS UPDRAFTS LATER TODAY. SHEAR WILL REMAIN STRONG UNDER 40+ KT WLY MID LEVEL FLOW WITH FORECAST SOUNDINGS MAINTAINING EFFECTIVE SHEAR IN EXCESS OF 50 KT. THOUGH SEVERE THREAT IS MORE CONDITIONAL ACROSS THIS REGION GIVEN LACK OF LARGE SCALE ASCENT UNDER RIDGING ALOFT...FORECAST SOUNDINGS SUGGEST SUPERCELLS WOULD BE LIKELY SHOULD INITIATION OCCUR ALONG DRY LINE/WEAK LOW CENTER EXPECTED TO FORM OVER SWRN TX. LARGE HAIL WILL BE PRIMARY SEVERE THREAT...ALONG WITH ISOLATED DAMAGING WINDS. TORNADO POTENTIAL MAY BE MODULATED BY WEAK LOW LEVEL SHEAR FORECAST ACROSS THE AREA. ..EVANS/JEWELL.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 16:35:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 12:35:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071632 SWODY1 SPC AC 071631 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1131 AM CDT SUN MAY 07 2006 VALID 071630Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FROM SE AL TO SRN SC.... ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTERNOON INTO EARLY TONIGHT FROM W TX TO CENTRAL NEB.... ...SE STATES TODAY... CONVECTION IS ONGOING IN A BROKEN BAND ALONG THE SURFACE COLD FRONT FROM SE LA ACROSS SRN MS/AL INTO GA...AND IN ASSOCIATION WITH A MID LEVEL SHORTWAVE TROUGH MOVING EWD OVER NRN MS/AL. SURFACE HEATING/ DESTABILIZATION SHOULD ALLOW SOME OF THESE STORMS TO INTENSIFY DURING THE AFTERNOON ACROSS SE AL AND CENTRAL/S GA AND SRN SC. EXPECT THE THREAT FOR DAMAGING WINDS AND ISOLATED LARGE HAIL TO INCREASE GRADUALLY THROUGH EARLY-MID AFTERNOON...IN AN ENVIRONMENT OF MODERATE INSTABILITY /MLCAPE VALUES OF 1000-1500 J/KG/ AND MODEST DEEP LAYER VERTICAL SHEAR /0-6 KM SHEAR OF 35-40 KT/. ...W TX TO THE DAKOTAS THIS AFTERNOON INTO EARLY TONIGHT... MORNING UPPER AIR ANALYSES AND WATER VAPOR IMAGERY SHOW AN ELONGATED MID LEVEL TROUGH FROM NW NM/CO TO MT THAT IS MOVING EWD TOWARD THE HIGH PLAINS. THIS MID LEVEL TROUGH WILL BE ACCOMPANIED BY A WEAK COLD FRONT ACROSS THE DAKOTAS...AND A DEVELOPING LEE TROUGH FARTHER S FROM WRN NEB ACROSS ERN CO TO ERN NM. BOUNDARY LAYER DEWPOINTS ARE EXPECTED TO RANGE FROM THE UPPER 40S ACROSS THE CENTRAL/ERN DAKOTAS TO THE MID 50S INTO THE TX PANHANDLE THIS AFTERNOON E OF THE SURFACE BOUNDARIES...WHILE SURFACE TEMPERATURES WARM INTO THE 70S W OF THE MORNING STRATUS. THE NET RESULT WILL BE MLCAPE VALUES OF 500-1000 J/KG IN A NARROW CORRIDOR ACROSS THE WRN PLAINS. THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID-LATE AFTERNOON ALONG THE COLD FRONT AND LEE TROUGH...WITH THE STRONGER INSTABILITY AND VERTICAL SHEAR FROM NEB SWD SUPPORTING A SOMEWHAT GREATER THREAT FOR LARGE HAIL/DAMAGING WINDS COMPARED TO THE DAKOTAS. MUCH OF THIS ACTIVITY SHOULD BE DIURNAL WITH A DECREASING SEVERE THREAT BY LATE EVENING. HOWEVER...INCREASING MOISTURE FROM THE S AND THE DEVELOPMENT OF A 30-35 KT LLJ MAY ALLOW A CONVECTIVE CLUSTER TO PERSIST OVERNIGHT INVOF THE RED RIVER VALLEY OF SW OK/NW TX. ...SW TX THIS AFTERNOON/EARLY TONIGHT... A SRN STREAM SHORTWAVE TROUGH IS LOCATED OVER NRN BAJA...THOUGH THIS TROUGH SHOULD DRIFT SEWD THROUGH TONIGHT AND REMAIN W OF TX. STILL...L0W-LEVEL MOISTURE /DEWPOINTS OF 60-68/ IS SPREADING NWWD ALONG THE MIDDLE RIO GRANDE AND LOWER PECOS VALLEYS...AND THE 12Z DRT/MAF SOUNDINGS INDICATE THAT CONVECTIVE INHIBITION WILL BECOME WEAK ONCE SURFACE TEMPERATURES REACH THE LOW-MID 80S. A FEW STORMS MAY FORM OVER THE HIGHER TERRAIN OF SW TX AND W/SW OF DRT...AND THIS CONVECTION SHOULD THEN MOVE GENERALLY EWD. THOUGH MID LEVEL LAPSE RATES ARE NOT AS STEEP AS PREVIOUS DAYS OVER THIS AREA...MLCAPE OF 1000-2000 J/KG IS STILL EXPECTED IN COMBINATION WITH VERTICAL SHEAR SUPPORTIVE OF SUPERCELLS. LARGE HAIL SHOULD BE THE PRIMARY SEVERE THREAT...WITH ISOLATED VERY LARGE HAIL POSSIBLE WITH ANY SUPERCELLS. ..THOMPSON/TAYLOR.. 05/07/2006  From swody1 at goshenarc.org Sun May 7 19:36:51 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 15:36:51 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071934 SWODY1 SPC AC 071932 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0232 PM CDT SUN MAY 07 2006 VALID 072000Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SERN ATLANTIC COAST INTO THE ERN FL PNHDL... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL AND SRN HIGH PLAINS... ...SC SWWD INTO SRN GA/NRN FL... MESOANALYSIS INDICATES SURFACE LOW OVER CNTRL SC AS OF 18Z WITH TRAILING COLD FRONT EXTENDING WSWWD THROUGH CNTRL PORTIONS OF GA AND AL INTO SERN MS. A MOIST AND MODERATELY UNSTABLE AIR MASS /MLCAPES OF 1000-1500 J/KG/...COUPLED WITH FORCING FOR ASCENT AHEAD OF SHORT WAVE TROUGH MOVING THROUGH THE TN VALLEY INTO THE SRN APPALACHIANS...HAS MAINTAINED STRONG/SEVERE CLUSTERS OF STORMS OVER CNTRL/SRN SC AND SWRN GA INTO THE FL PNHDL AND N-CNTRL FL. REGIONAL VWPS INDICATE LARGELY UNDIRECTIONAL 45-55 KT VERTICAL SHEAR...THOUGH LOW-LEVEL SHEAR IS LOCALLY STRONGER NEAR SC SURFACE LOW. EXPECT THE POTENTIAL FOR PRIMARILY DAMAGING WINDS AND LARGE HAIL TO CONTINUE THIS AFTERNOON INTO TONIGHT IN ASSOCIATION WITH BOWING LINE SEGMENTS AND EMBEDDED SUPERCELLS ACROSS SRN GA AND NRN FL. SOME THREAT OF ISOLATED TORNADOES WILL EXIST THROUGH THE AFTERNOON ALONG THE SC COAST WHERE LOW-LEVEL HODOGRAPHS WILL REMAIN MORE STRONGLY CURVED. ...SWRN TX... WRN EXTENSION OF SYNOPTIC FRONT HAS STARTED TO RETREAT NWD THROUGH WRN TX THIS AFTERNOON WITH MESOANALYSIS DEPICTING THIS BOUNDARY FROM FAR SERN NM SEWD TO NEAR SAT AS OF 18Z. AIR MASS S OF FRONT REMAINS RELATIVELY MOIST AND MODERATELY UNSTABLE WITH DEWPOINTS IN THE UPPER 50S TO MID 60S...CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. VISIBLE SATELLITE IMAGERY INDICATES THAT CUMULUS DEVELOPMENT IS DEEPENING ALONG THE HIGHER TERRAIN OF SWRN TX /GLASS AND DAVIS MOUNTAINS/ ALONG WRN EDGE OF INSTABILITY AXIS. CONTINUED HEATING AND OROGRAPHIC FORCING SHOULD SUPPORT ISOLATED TO WIDELY SCATTERED STORM DEVELOPMENT BY MID TO LATE AFTERNOON WITH STORMS MOVING OFF THE HIGH TERRAIN INTO A PROGRESSIVELY MORE UNSTABLE ENVIRONMENT. SELY SURFACE WINDS BENEATH 40-50 KTS AT 6 KM AND 90-100 KTS AT 9 KM AGL /PER WHITE SANDS NM PROFILER/ WILL SUPPORT SUPERCELLS CAPABLE OF PRIMARILY LARGE HAIL. THOUGH NOT AS LIKELY...ADDITIONAL ISOLATED STORM DEVELOPMENT MAY ALSO OCCUR ALONG RETREATING WARM FRONT OVER THE NRN/CNTRL PERMIAN BASIN INTO SERN NM...PERHAPS SEWD INTO THE CONCHO VALLEY WHERE ENVIRONMENT WOULD ALSO BE SUPPORTIVE OF SUPERCELLS. ...SWRN NEB INTO THE TX PNHDL... AFTERNOON WATER VAPOR IMAGERY SHOWS SHORT WAVE TROUGH TRANSLATING EWD INTO THE CNTRL HIGH PLAINS...WHICH COUPLED WITH RATHER STEEP LOW AND MID-LEVEL LAPSE RATES...IS SUPPORTING CONVECTIVE DEVELOPMENT NEAR GLD. DESPITE MODEST SURFACE DEWPOINTS IN THE UPPER 40S TO LOWER 50S...CONTINUED DAYTIME HEATING AND THESE LAPSE RATES SHOULD CONTRIBUTE TO MLCAPES OF 500-1000 J/KG BY LATE AFTERNOON. TSTMS ARE EXPECTED TO INCREASE IN COVERAGE ALONG LEE TROUGH OR WEAK DRY LINE FROM SWRN NEB INTO THE TX PNHDL THIS AFTERNOON AND EVENING. TUCUMCARI NM AND GRENADA CO PROFILERS BOTH INDICATE ROUGHLY 30-35 KT MID-LEVEL FLOW WITH A NOTICEABLY STRONGER INCREASE AT HIGH-LEVELS /100-110 KTS/ FARTHER S ACROSS NERN NM AND THE TX PNHDL. MARGINAL SHEAR ACROSS NRN PORTION OF SLIGHT RISK AREA WILL LARGELY SUPPORT MULTICELLULAR CONVECTION CAPABLE OF GUSTY WINDS AND LARGE HAIL. HOWEVER...FARTHER S FROM SWRN KS INTO THE TX PNHDL...SUPERCELLS APPEAR MORE LIKELY WITH A THREAT OF PRIMARILY LARGE HAIL. ...WRN AND CNTRL DAKOTAS... RADAR IMAGERY SHOWS TSTMS INCREASING IN COVERAGE THIS AFTERNOON ALONG COLD FRONT FROM THE BLACK HILLS NEWD INTO CNTRL ND WITHIN ENVIRONMENT CHARACTERIZED BY STEEP LOW AND MID-LEVEL LAPSE RATES AND MLCAPES OF 500 J/KG. VERTICAL SHEAR REMAINS RELATIVELY WEAK...THOUGH THE PRESENCE OF THE STEEP LAPSE RATES MAY PROMOTE LOCALLY STRONG WIND GUSTS AND MARGINAL HAIL WITH THE STRONGEST STORMS. ..MEAD.. 05/07/2006  From swody1 at goshenarc.org Mon May 8 01:03:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 07 May 2006 21:03:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080101 SWODY1 SPC AC 080059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT SUN MAY 07 2006 VALID 080100Z - 081200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SWRN KS SWD ACROSS TX... ...CENTRAL HIGH PLAINS SWD TO THE RIO GRANDE... THUNDERSTORMS CONTINUE TO INCREASE IN COVERAGE OVER SWRN KS AND THE TX/OK PANHANDLES...WHILE OTHER STORMS PERSIST ACROSS PARTS OF THE TRANSPECOS AND INTO THE TX BIG BEND/RIO GRANDE VALLEY. EVENING MAF RAOB REVEALS FAVORABLE KINEMATIC AND THERMODYNAMIC ENVIRONMENT FOR SEVERE/SUPERCELL STORMS. THREAT FOR LARGE HAIL AND DAMAGING WINDS -- AND PERHAPS AN ISOLATED TORNADO -- SHOULD CONTINUE THIS EVENING...WHILE SPREADING EWD TOWARD CENTRAL TX AS LOW-LEVEL JET/WARM ADVECTION INCREASES AHEAD OF APPROACHING UPPER TROUGH. THOUGH CONDITIONS ARE SLIGHTLY LESS FAVORABLE NWD INTO SWRN KS...DEVELOPING LOW-LEVEL JET SHOULD ALLOW CONVECTION TO PERSIST/INCREASE WHILE MOVING SEWD ACROSS THE HIGH PLAINS AND INTO PARTS OF OK/N TX. PRIMARY THREAT WILL BE HAIL AND LOCALLY DAMAGING GUSTS...WITH STORMS ACROSS THIS AREA LIKELY CONTINUING THROUGH THE PERIOD. ...THE SOUTHEAST... CLUSTER OF SEVERE STORMS HAS MOVED OFF THE SC COAST...THOUGH NEW STORMS CONTINUE TO DEVELOP ACROSS CENTRAL GA NEAR INTERSECTION OF WEDGE FRONT AND COLD FRONT...AND SWWD INTO SRN AL ALONG COLD FRONT. HOWEVER...DESPITE SUFFICIENT WIND FIELD...EVENING SOUNDINGS REVEAL WEAK LAPSE RATES/LIMITED INSTABILITY...AND THEREFORE EXPECT SEVERE THREAT ACROSS THIS REGION TO REMAIN LIMITED AS WELL. THOUGH A FEW MARGINAL SEVERE REPORTS WILL BE POSSIBLE THROUGH THIS EVENING...SLOW STABILIZATION OF AIRMASS SHOULD RESULT IN A CONTINUED DECREASE IN THREAT...AND THUS WILL DROP THE SLIGHT RISK AND CARRY ONLY LOW SEVERE PROBABILITIES THROUGH THE REMAINDER OF THE PERIOD. ...NRN PLAINS... THUNDERSTORMS CONTINUE ACROSS THE DAKOTAS AND INTO NEB AHEAD OF COLD FRONT...WHERE 1000 TO 1500 J/KG MEAN-LAYER CAPE PERSISTS. HOWEVER...DEEP-LAYER SHEAR AHEAD OF FRONT -- PARTICULARLY ACROSS THE DAKOTAS -- REMAINS WEAK. THIS COMBINED WITH BOUNDARY LAYER STABILIZATION OVERNIGHT SUGGESTS THAT ANY REMAINING SEVERE THREAT SHOULD WANE THROUGH THE EVENING. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 06:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 02:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080604 SWODY1 SPC AC 080602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0102 AM CDT MON MAY 08 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM MN SSWWD ACROSS THE MIDDLE MO VALLEY INTO THE SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX EWD INTO THE GULF COAST REGION... ...SYNOPSIS... UPPER SHORT-WAVE TROUGH RESPONSIBLE FOR CURRENT CONVECTION WILL MOVE EWD INTO THE MS VALLEY REGION THROUGH THE FIRST HALF OF THE DAY 1 PERIOD...FOLLOWED BY A SECOND TROUGH MOVING OUT OF THE ROCKIES/INTO THE PLAINS. A COLD FRONT SHOULD LINGER W-E ACROSS THE GULF COAST STATES...POSSIBLY DRIFTING SLOWLY NWD AS A WARM FRONT ACROSS THE WRN AND CENTRAL GULF COAST REGION DURING THE AFTERNOON. MEANWHILE...COLD FRONT ASSOCIATED WITH SECOND SHORT-WAVE TROUGH WILL MOVE EWD/SEWD ACROSS THE NRN AND CENTRAL PLAINS. BOTH OF THESE BOUNDARIES SHOULD SERVE AS FOCUSING MECHANISMS FOR THUNDERSTORM DEVELOPMENT -- PARTICULARLY FROM AFTERNOON ONWARD. ...MN SSWWD ACROSS THE MID MO VALLEY INTO OK... A FEW SHOWERS MAY LINGER INTO THE START OF THE DAY 1 PERIOD AHEAD OF FRONT ACROSS THE NRN PLAINS...WHEN DAYTIME HEATING/DESTABILIZATION COMMENCES. BY AFTERNOON...EXPECT 1000 TO 2000 J/KG MEAN-LAYER CAPE TO DEVELOP...WHEN FORCING ALONG FRONT/AHEAD OF WEAK SHORT-WAVE TROUGH SHOULD RESULT IN THUNDERSTORM INITIATION. THOUGH DEEP-LAYER WIND FIELD WILL NOT BE PARTICULARLY STRONG...SUFFICIENT SHEAR SHOULD EXIST FOR ORGANIZED/ROTATING STORMS TO DEVELOP -- PARTICULARLY ACROSS ERN NEB AND SWD INTO KS/OK. EXPECT LARGE HAIL TO BECOME THE MAIN SEVERE THREAT...THOUGH LOCALLY DAMAGING WINDS WILL ALSO BE POSSIBLE. AS LOW-LEVEL JET DEVELOPS DURING THE EVENING...MCS IS EXPECTED TO EVOLVE ACROSS PARTS OF KS/OK WHICH SHOULD MOVE EWD INTO MO/AR BY THE END OF THE PERIOD. THOUGH SEVERE POTENTIAL SHOULD DIMINISH OVERNIGHT...LOW-PROBABILITY THREAT MAY LINGER THROUGH THE END OF THE PERIOD. ...E TX/LA/SRN MS... FORECAST FOR THIS REGION IS COMPLICATED BY QUESTIONS REGARDING EVOLUTION OF ONGOING CONVECTION MOVING ESEWD ACROSS SRN KS/OK...AND MCS PROGRESSING EWD OVER CENTRAL TX. THOUGH DETAILS OF SEVERE POTENTIAL ARE THERFORE UNCLEAR...IT APPEARS THAT FRONT NOW EXTENDING FROM CENTRAL GA WSWWD ACROSS SRN LA SHOULD MOVE SLOWLY NWD AS A WARM FRONT...AND SERVE AS A FOCUS FOR CONVECTIVE DEVELOPMENT. WITH VERY MOIST AIRMASS S OF THIS BOUNDARY...SUFFICIENT INSTABILITY SHOULD EVOLVE...WHICH COMBINED WITH LARGE SCALE UVV AHEAD OF SHORT-WAVE TROUGH SHOULD YIELD INCREASINGLY ACTIVE CONVECTION ACROSS THIS REGION. MODERATE MID-LEVEL FLOW WITHIN SRN STREAM SHOULD YIELD SHEAR SUFFICIENT FOR SEVERE/SUPERCELL STORMS. MAIN SEVERE THREATS SHOULD BE HAIL AND LOCALLY DAMAGING WINDS. DEPENDING UPON EVOLUTION OF CONVECTION ONGOING ATTM...AREAS OF GREATER SEVERE PROBABILITY WITHIN THE LARGE SLIGHT RISK AREA MAY BECOME APPARENT IN LATER OUTLOOKS. STORMS SHOULD ALSO DEVELOP EWD ALONG FRONT ACROSS THE GULF COAST/SOUTHEAST...THOUGH OVERALL THREAT SHOULD BE REMAIN MORE LIMITED DUE TO SOMEWHAT WEAKER FLOW ALOFT AND WEAKER LARGE-SCALE UVV. OVERALL THREAT SHOULD DIMINISH OVERNIGHT WITH THE LOSS OF DAYTIME HEATING...THOUGH LIMITED POTENTIAL MAY LINGER ALONG FRONT INTO THE OVERNIGHT HOURS. ..GOSS.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 13:02:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 09:02:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081259 SWODY1 SPC AC 081257 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 AM CDT MON MAY 08 2006 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL/ERN TX INTO NRN FL... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN/CENTRAL PLAINS... ...LA EWD ACROSS THE CENTRAL GULF COAST/NRN FL... BOUNDARY LAYER AIR MASS IS VERY MOIST ALONG AND SOUTH OF STALLED SURFACE FRONT EXTENDING FROM FAR SRN GA/NRN FL WWD INTO SERN TX THIS MORNING. SURFACE DEW POINTS IN THE LOW TO MID 70S WERE OBSERVED ALONG AND JUST OFF THE GULF COAST. THIS BOUNDARY WILL MOVE LITTLE THROUGH THE DAY WHILE MODERATE TO STRONG WLY MID LEVEL FLOW PERSISTS FROM THE SRN PLAINS INTO NRN FL...WITH H5 WINDS FROM 40-50 KT. THOUGH MID LEVEL LAPSE RATES REMAIN MODEST...ABUNDANT MOISTURE WILL SUPPORT STRONG INSTABILITY BY THE EARLY AFTERNOON ACROSS THE CENTRAL GULF COAST WITH LESSER INSTABILITY FORECAST INTO NRN FL. DESPITE ILL-DEFINED FOCUSING MECHANISMS ALOFT ON MORNING WV IMAGERY... HEATING AND CONVERGENCE INVOF SURFACE FRONT AND SEA-BREEZES SHOULD SUPPORT WIDESPREAD STRONG TO SEVERE THUNDERSTORMS ACROSS THIS REGION BY THE LATE MORNING/EARLY AFTERNOON. EFFECTIVE SHEAR WILL REMAIN SUPPORTIVE OF SUPERCELLS AND ORGANIZED MULTICELL CLUSTERS/LINES AS ACTIVITY INCREASES THROUGH THE DAY BOTH IN COVERAGE AND INTENSITY. DAMAGING WINDS AND LARGE HAIL ARE EXPECTED TO BE PRIMARY SEVERE THREATS...THOUGH FORECAST STORM MOTIONS ALONG STALLED SURFACE BOUNDARY MAY SUPPORT A TORNADO OR TWO WHERE LOW LEVEL SHEAR CAN BE MAXIMIZED JUST NORTH OF THE FRONT. ...CENTRAL/ERN TX INTO WRN LA... STRONG HEATING WILL DEVELOP ACROSS WRN AND CENTRAL TX TODAY AND ALLOW DRY LINE TO MIX WELL EWD...POSSIBLY INTO THE I-35 CORRIDOR BY LATE IN THE DAY. LARGE SCALE ASCENT WILL REMAIN WEAK ACROSS THE REGION THOUGH STRONG HEATING AND CONVERGENCE ALONG DRY LINE AND PERSISTENT OUTFLOW BOUNDARIES SHOULD SUPPORT RAPID THUNDERSTORM DEVELOPMENT AS CAP WEAKENS LATE THIS AFTERNOON AND EVENING. FORECAST SOUNDINGS INDICATE AN EXTREMELY UNSTABLE WARM SECTOR GIVEN UPPER 60F/LOWER 70F SURFACE DEW POINTS EXPECTED TO SPREAD NWD TODAY...WITH MLCAPE IN EXCESS OF 3000 J/KG BY 21Z. IN ADDITION... 45+ KT OF DEEP LAYER SHEAR WILL REMAIN MORE THAN ADEQUATE FOR SUPERCELLS PRODUCING VERY LARGE HAIL...ALONG WITH DAMAGING WINDS AND POSSIBLY ISOLATED TORNADOES. ...NRN MS RIVER VALLEY ACROSS THE CENTRAL PLAINS... SURFACE COLD FRONT WILL ADVANCE EWD ACROSS THE NRN PLAINS AND SEWD INTO THE CENTRAL PLAINS TODAY AHEAD OF NEXT IN A SERIES OF FAST MOVING SHORTWAVE TROUGHS MOVING ACROSS THE CENTRAL/NRN ROCKIES. THOUGH LOW LEVEL MOISTURE WILL REMAIN MODEST...50+ F SURFACE DEW POINTS WILL BE SUFFICIENT FOR NARROW AXIS OF MARGINAL TO MODERATE INSTABILITY ALONG AND AHEAD OF THIS FRONT GIVEN STEEP LAPSE RATES. EXPECT SEVERAL CLUSTERS/LINES AND SUPERCELLS WILL DEVELOP LATER TODAY...WITH MORE CONCENTRATED/INTENSE DEVELOPMENT EXPECTED ACROSS THE MID MO RIVER VALLEY INTO CENTRAL KS WHERE MLCAPE AND CONVERGENCE ALONG WEAK SURFACE LOW WILL BE GREATER. LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE THREATS. FORECAST SOUNDINGS AND SUB-60F SURFACE DEW POINTS SUGGEST TORNADO THREAT MAY BE MITIGATED A BIT BY RELATIVELY HIGH LCLS THIS AFTERNOON. HOWEVER...PRESENCE OF SURFACE LOW AND MODEST SLY LLJ WILL SUPPORT SUFFICIENT LOW LEVEL SHEAR FOR INCLUSION OF TORNADO PROBABILITIES INTO THE CENTRAL PLAINS. ACTIVITY OVER SERN NEB/KS SHOULD EVOLVE INTO ONE OR MORE MCS/S AND SHIFT SEWD OVERNIGHT ALONG NOSE OF INCREASING SWLY LLJ ACROSS THE OZARK PLATEAU/NERN OK WITH ATTENDANT THREAT OF LARGE HAIL AND ISOLATED DAMAGING WINDS. ..EVANS/JEWELL.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 16:38:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 12:38:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081633 SWODY1 SPC AC 081632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT MON MAY 08 2006 VALID 081630Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS THE GULF COAST INTO CENTRAL TX.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO TONIGHT ACROSS THE CENTRAL PLAINS.... ...CENTRAL KS TO ERN NEB THIS AFTERNOON/EVENING... A SURFACE LEE TROUGH/DRYLINE WILL BECOME BETTER DEFINED THIS AFTERNOON FROM ERN NEB TO CENTRAL KS...S OF A WEAK TRIPLE POINT LOW INVOF NE NEB. STEEP MID LEVEL LAPSE RATES OVER THE HIGH PLAINS THIS MORNING WILL SPREAD EWD OVER THE CENTRAL PLAINS BY AFTERNOON...ABOVE A WARMING AND GRADUALLY MOISTENING BOUNDARY LAYER WITH AFTERNOON TEMPERATURES OF 75-80 F AND DEWPOINTS RANGING FROM THE UPPER 50S IN ERN NEB TO LOWER 60S IN KS. THIS WILL RESULT IN AFTERNOON MLCAPE VALUES OF 1500-2500 J/KG ALONG AND E OF THE SURFACE TROUGH. THUNDERSTORM INITIATION IS ANTICIPATED IN THE 21-23Z TIME FRAME ALONG THE SURFACE TROUGH FROM SE NEB INTO CENTRAL KS...AS A SUBTLE MID LEVEL WAVE PROGRESSES EWD OVER THE CENTRAL/NRN PLAINS IN ADVANCE OF THE PRIMARY TROUGH OVER THE NRN ROCKIES. VERTICAL SHEAR/ INSTABILITY AND SHEAR VECTOR/BOUNDARY ORIENTATIONS APPEAR SUFFICIENT FOR DISCRETE SUPERCELLS THE FIRST FEW HOURS AFTER INITIATION. LATER IN THE EVENING...CONVECTION MAY GROW UPSCALE INTO ONE OR MORE MCS/S AND MOVE ESEWD TOWARD WRN MO AND N/NE OK. VERY LARGE HAIL AND A COUPLE OF TORNADOES WILL BE POSSIBLE WITH THE AFTERNOON/EVENING SUPERCELLS...WHILE WIND DAMAGE AND LARGE HAIL SHOULD BECOME THE MAIN THREATS BY TONIGHT...PRIMARILY ALONG THE SRN FLANK OF ANY CONVECTIVE CLUSTERS. ...GULF COAST THIS AFTERNOON... A STALLED BAROCLINIC ZONE NEAR THE I-10 CORRIDOR WILL SERVE AS A FOCUS FOR THUNDERSTORM DEVELOPMENT THROUGH THE AFTERNOON FROM SRN LA EWD TO N FL/EXTREME S GA. MORNING SOUNDINGS ACROSS THIS AREA SHOW THE POTENTIAL FOR MLCAPE VALUES OF 1500-2000 J/KG WITH DAYTIME HEATING...AND RELATIVELY WEAK CONVECTIVE INHIBITION. GIVEN THE MODERATE INSTABILITY AND STRONGER MID-UPPER LEVEL FLOW...STORMS WITH SOME SUPERCELL CHARACTERISTICS WILL BE POSSIBLE. HOWEVER...MID LEVEL LAPSE RATES ARE RATHER MODEST /6.5 C/KM/ AND LOW-LEVEL FLOW/SHEAR IS ALSO RELATIVELY WEAK...AND BOTH OF THESE FACTORS MAY TEND TO LIMIT THE SEVERE THREAT SOMEWHAT. ISOLATED/MARGINAL DAMAGING WINDS AND HAIL ARE EXPECTED TO BE THE MAIN THREATS THROUGH THE AFTERNOON. ...TX AREA THIS AFTERNOON/EVENING... SUBSTANTIAL UNCERTAINTY EXISTS REGARDING CONVECTIVE INITIATION THIS AFTERNOON ACROSS TX. THE OUTFLOW FROM AN EARLIER CONVECTIVE CLUSTER IS NOW BECOMING DIFFUSE FROM N CENTRAL INTO E CENTRAL TX...AND THIS RESIDUAL OUTFLOW IS MASKING THE LOCATION OF THE WEAKENING BAROCLINIC ZONE ACROSS TX. MODIFIED MORNING SOUNDINGS /AS WELL AS SHORT TERM MODEL FORECASTS/ SHOW THE POTENTIAL FOR MLCAPE OF 3000-4000 J/KG THIS AFTERNOON ACROSS CENTRAL TX...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. ISOLATED THUNDERSTORMS MAY DEVELOP ALONG THE RESIDUAL OUTFLOW...AND PERHAPS OVER CENTRAL TX NEAR THE OUTFLOW/DRYLINE MERGER AND SWD ALONG THE DRYLINE. IF STORMS DO FORM...VERY LARGE HAIL WILL BE POSSIBLE. ..THOMPSON/TAYLOR.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 20:15:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 16:15:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 082011 SWODY1 SPC AC 082010 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0310 PM CDT MON MAY 08 2006 VALID 082000Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN FL WWD ALONG THE GULF COAST AND ACROSS PARTS OF THE LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL AND SRN PLAINS... ...GULF COAST... STORMS WERE CONSOLIDATING ALONG STALLED FRONTAL ZONE FROM SRN GA/NERN FL WWD ACROSS THE FL PNHDL. ADDITIONAL ACTIVITY MAY FORM INVOF THIS BOUNDARY OVER THE NEXT SEVERAL HOURS FROM MOBILE AREA WWD/NWWD INTO LA. HOWEVER...STORM COVERAGE WITH WWD EXTENT MAY BE SOMEWHAT MORE LIMITED BY LACK OF STRONGER LARGE SCALE FORCING FOR UPWARD VERTICAL MOTION. MOIST AND VERY UNSTABLE AIR MASS ALONG THE BOUNDARY WILL CONTINUE TO FUEL STOUT UPDRAFTS. WHILE LOW LEVEL FLOW/SHEAR REMAINS SOMEWHAT WEAK...DEEP LAYER SHEAR IS MORE THAN ADEQUATE FOR UPDRAFT PERSISTENCE GIVEN 50KT MID LEVEL FLOW. STRONG CELLS/MULTICELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND SOME HAIL. GIVEN GENERALLY WEAK LARGE SCALE FORCING...DIURNAL WEAKENING SHOULD COMMENCE WITHIN A FEW HOUR AFTER SUNSET. ...CNTRL/SRN PLAINS... COLD FRONT CURRENTLY SITUATED FROM ERN SD SWWD ACROSS CNTRL NEB INTO NWRN KS IS EXPECTED TO BECOME A FOCUS FOR TSTM DEVELOPMENT BY LATE AFTERNOON. DRYLINE EXTENDS SWWD FROM THE COLD FRONT...FROM WRN KS TO TX BIG BEND AREA. WATER VAPOR IMAGERY LOOP DEPICTS A NUMBER OF SHORT WAVE FEATURES SPREADING ESEWD FROM THE ROCKIES TOWARD THE PLAINS AND LIFT ASSOCIATED WITH THESE IMPULSES SHOULD FURTHER AID STORM DEVELOPMENT NEAR THE FRONT AND DRYLINE THROUGH THIS EVENING. AT PRESENT...WARM SECTOR OVER TX REMAINS CAPPED. HOWEVER...VERY STRONG HEATING AHEAD OF THE DRYLINE SHOULD PROMOTE AT LEAST ISOLATED STORM INITIATION ACROSS WRN/NWRN TX. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS ACTIVITY WILL REMAIN ISOLATED THROUGH THIS PERIOD AS STRONGER LARGE SCALE FORCING REMAINS TO THE NORTH NEAR THE COLD FRONT. AS THE COLD FRONT DEVELOPS EAST ACROSS KS/NEB AREA THROUGH THIS EVENING...RESULTING LIFT WILL ACT ON INCREASINGLY MOIST AND UNSTABLE AIR MASS. STORMS...IN CLUSTERS AND LINE SEGMENTS...WITH SOME SUPERCELL POTENTIAL...WILL DEVELOP EAST ACROSS ERN NEB AND CNTRL AND ERN KS. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. WEAK WAVE ALONG THE FRONT OVER NEB...AND GREATER INSTABILITY AHEAD OF THE FRONT OVER KS... MAY FOSTER GREATER LOW LEVEL SHEAR/STRETCHING WITH AN ENHANCED TORNADO THREAT POSSIBLY EVOLVING IN THESE AREAS. CONVECTION SHOULD MERGE INTO AN MCS OR TWO FROM ERN KS INTO WRN IA THROUGH LATE EVENING WITH SOME SEVERE HAIL/WIND THREAT CONTINUING. SEVERE POTENTIAL MAY PERSIST WITH THE MCS FORECAST TO DEVELOP INTO SERN KS/NERN OK AND WRN MO/AR THROUGH EARLY TUESDAY WHERE GREATER INSTABILITY AND FORCING WILL EXIST ON THE NOSE OF INTENSIFYING LOW LEVEL JET. ...MN... ISOLATED STRONG STORMS WERE DEVELOPING WITHIN WEAK INSTABILITY AXIS AHEAD OF THE COLD FRONT OVER WRN/NCNTRL MN. WHILE LOW STATIC STABILITY AND MODEST FORCING SHOULD MAINTAIN CONVECTION...MID LEVEL FLOW IS FORECAST TO WEAKEN WITHIN MID LEVEL TROUGH AXIS THROUGH THE EVENING. HAIL APPEARS TO BE THE MAIN SEVERE WEATHER THREAT WITH THIS ACTIVITY OVER THE NEXT FEW HOURS. ..CARBIN.. 05/08/2006  From swody1 at goshenarc.org Mon May 8 21:16:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 17:16:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 082111 SWODY1 SPC AC 082109 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0409 PM CDT MON MAY 08 2006 VALID 082000Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN FL WWD ALONG THE GULF COAST AND ACROSS PARTS OF THE LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CNTRL AND SRN PLAINS... CORRECTED FOR NDFD GRID POINTS PRODUCT ...GULF COAST... STORMS WERE CONSOLIDATING ALONG STALLED FRONTAL ZONE FROM SRN GA/NERN FL WWD ACROSS THE FL PNHDL. ADDITIONAL ACTIVITY MAY FORM INVOF THIS BOUNDARY OVER THE NEXT SEVERAL HOURS FROM MOBILE AREA WWD/NWWD INTO LA. HOWEVER...STORM COVERAGE WITH WWD EXTENT MAY BE SOMEWHAT MORE LIMITED BY LACK OF STRONGER LARGE SCALE FORCING FOR UPWARD VERTICAL MOTION. MOIST AND VERY UNSTABLE AIR MASS ALONG THE BOUNDARY WILL CONTINUE TO FUEL STOUT UPDRAFTS. WHILE LOW LEVEL FLOW/SHEAR REMAINS SOMEWHAT WEAK...DEEP LAYER SHEAR IS MORE THAN ADEQUATE FOR UPDRAFT PERSISTENCE GIVEN 50KT MID LEVEL FLOW. STRONG CELLS/MULTICELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND SOME HAIL. GIVEN GENERALLY WEAK LARGE SCALE FORCING...DIURNAL WEAKENING SHOULD COMMENCE WITHIN A FEW HOUR AFTER SUNSET. ...CNTRL/SRN PLAINS... COLD FRONT CURRENTLY SITUATED FROM ERN SD SWWD ACROSS CNTRL NEB INTO NWRN KS IS EXPECTED TO BECOME A FOCUS FOR TSTM DEVELOPMENT BY LATE AFTERNOON. DRYLINE EXTENDS SWWD FROM THE COLD FRONT...FROM WRN KS TO TX BIG BEND AREA. WATER VAPOR IMAGERY LOOP DEPICTS A NUMBER OF SHORT WAVE FEATURES SPREADING ESEWD FROM THE ROCKIES TOWARD THE PLAINS AND LIFT ASSOCIATED WITH THESE IMPULSES SHOULD FURTHER AID STORM DEVELOPMENT NEAR THE FRONT AND DRYLINE THROUGH THIS EVENING. AT PRESENT...WARM SECTOR OVER TX REMAINS CAPPED. HOWEVER...VERY STRONG HEATING AHEAD OF THE DRYLINE SHOULD PROMOTE AT LEAST ISOLATED STORM INITIATION ACROSS WRN/NWRN TX. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS ACTIVITY WILL REMAIN ISOLATED THROUGH THIS PERIOD AS STRONGER LARGE SCALE FORCING REMAINS TO THE NORTH NEAR THE COLD FRONT. AS THE COLD FRONT DEVELOPS EAST ACROSS KS/NEB AREA THROUGH THIS EVENING...RESULTING LIFT WILL ACT ON INCREASINGLY MOIST AND UNSTABLE AIR MASS. STORMS...IN CLUSTERS AND LINE SEGMENTS...WITH SOME SUPERCELL POTENTIAL...WILL DEVELOP EAST ACROSS ERN NEB AND CNTRL AND ERN KS. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. WEAK WAVE ALONG THE FRONT OVER NEB...AND GREATER INSTABILITY AHEAD OF THE FRONT OVER KS... MAY FOSTER GREATER LOW LEVEL SHEAR/STRETCHING WITH AN ENHANCED TORNADO THREAT POSSIBLY EVOLVING IN THESE AREAS. CONVECTION SHOULD MERGE INTO AN MCS OR TWO FROM ERN KS INTO WRN IA THROUGH LATE EVENING WITH SOME SEVERE HAIL/WIND THREAT CONTINUING. SEVERE POTENTIAL MAY PERSIST WITH THE MCS FORECAST TO DEVELOP INTO SERN KS/NERN OK AND WRN MO/AR THROUGH EARLY TUESDAY WHERE GREATER INSTABILITY AND FORCING WILL EXIST ON THE NOSE OF INTENSIFYING LOW LEVEL JET. ...MN... ISOLATED STRONG STORMS WERE DEVELOPING WITHIN WEAK INSTABILITY AXIS AHEAD OF THE COLD FRONT OVER WRN/NCNTRL MN. WHILE LOW STATIC STABILITY AND MODEST FORCING SHOULD MAINTAIN CONVECTION...MID LEVEL FLOW IS FORECAST TO WEAKEN WITHIN MID LEVEL TROUGH AXIS THROUGH THE EVENING. HAIL APPEARS TO BE THE MAIN SEVERE WEATHER THREAT WITH THIS ACTIVITY OVER THE NEXT FEW HOURS. ..CARBIN.. 05/08/2006  From swody1 at goshenarc.org Tue May 9 01:09:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 08 May 2006 21:09:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 090107 SWODY1 SPC AC 090106 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT MON MAY 08 2006 VALID 090100Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDDLE MO VALLEY SWWD INTO OK/NWRN AR... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL GULF COAST REGION... ...MID MO VALLEY SWWWD INTO KS/NRN OK/ERN MO/NWRN AR... LINE OF STORMS HAS EVOLVED FROM ERN NEB SWWD INTO SWRN KS...WITH EMBEDDED LEWP/BOW-TYPE STRUCTURES. STORMS SHOULD CONTINUE/INCREASE OVERNIGHT AS LOW-LEVEL JET STRENGTHENS...AND SPREAD ESEWD INTO WRN MO/NRN OK/NWRN AR. THOUGH DEEP-LAYER WIND FIELD IS NOT OVERLY STRONG...SHEAR IS SUFFICIENT FOR A CONTINUATION OF ORGANIZED STORMS AND A THREAT FOR MAINLY HAIL/DAMAGING WINDS THROUGH THE END OF THE PERIOD. ...CENTRAL GULF COAST REGION... THUNDERSTORMS -- INCLUDING A FEW SUPERCELLS -- HAVE INCREASED RECENTLY ACROSS ERN LA/SRN MS/SRN AL WITHIN MOIST/MODERATELY UNSTABLE AIRMASS. EVENING LIX /SLIDELL LA/ RAOB INDICATED 60 KT WNWLY MID-LEVEL FLOW...CONTRIBUTING TO DEEP-LAYER SHEAR VERY FAVORABLE FOR SUPERCELLS. EXPECT POTENTIAL FOR LARGE HAIL AND LOCALLY DAMAGING WINDS -- AND ISOLATED TORNADOES -- THROUGH THIS EVENING...THOUGH SEVERE THREAT SHOULD EXHIBIT A DIURNALLY-DRIVEN DECREASE LATE THIS EVENING/OVERNIGHT. ..GOSS.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 12:40:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 08:40:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 091237 SWODY1 SPC AC 091235 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0735 AM CDT TUE MAY 09 2006 VALID 091300Z - 101200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF ERN OK AND NWRN AR... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OK/TX PANHANDLE REGION TO THE CENTRAL GULF COAST... ...SYNOPSIS... A SERIES OF FAST MOVING SHORTWAVE TROUGHS ARE EVIDENT ON WV IMAGERY THIS MORNING EJECTING AWAY FROM BROADER MID/UPPER LEVEL TROUGH OVER THE ROCKIES. ONE SYSTEM IS NOW MOVING ACROSS CENTRAL TX AND WILL OVERSPREAD THE LOWER MS RIVER VALLEY/CENTRAL GULF COAST REGION TODAY. ANOTHER APPEARS TO BE MOVING INTO THE CENTRAL ROCKIES WHICH IS FORECAST TO BECOME BETTER DEFINED AS IT SHIFTS ACROSS THE SRN HIGH PLAINS AND OVER OK/KS LATER TONIGHT. AT THE SURFACE...PRIMARY COLD FRONT NOW EXTENDS FROM CENTRAL IA INTO W-CENTRAL TX WHICH HAS BEEN CONVECTIVELY-REINFORCED ACROSS NERN/CENTRAL OK FROM ONGOING MCS NOW MOVING INTO THE OZARK REGION. IN ADDITION...WEAK LOW CENTER WAS ANALYZED OVER SWRN OK ALONG COLD FRONT/DRY LINE TRIPLE POINT...WITH WARM FRONT DELINEATING VERY MOIST/MARINE AIR EXTENDING FROM SRN LA INTO CENTRAL OK. ...SRN HIGH PLAINS INTO THE LOWER MS RIVER VALLEY/MID SOUTH... FORECAST REMAINS COMPLEX THIS MORNING DUE TO UNCERTAINTY ABOUT EFFECTS OF ONGOING MCS. 09Z RUC MAINTAINS SSWLY LLJ INTO NRN AR THROUGH THE MORNING AND SHOULD SUPPORT CONTINUED STRONG/SEVERE THUNDERSTORMS ACROSS THE OZARK PLATEAU AND NRN AR WITH THREATS OF LARGE HAIL AND DAMAGING WINDS. ACTIVITY MAY INTENSIFY INTO THE BOOTHEEL REGION OF MO/MID SOUTH LATER THIS MORNING/EARLY THIS AFTERNOON ALONG NOSE OF THIS JET AS MODERATE INSTABILITY DEVELOPS. VERTICAL MOTION SHOULD BECOME QUITE WEAK ACROSS THE REGION FOR MUCH OF THE DAY...THOUGH ABUNDANT MOISTURE WITH SURFACE DEW POINTS IN THE LOWER TO MID 70S AND VERY STEEP LAPSE RATES WILL SUPPORT EXTREMELY UNSTABLE AIR MASS. HOWEVER...AREA WILL BE STRONGLY CAPPED UNDER 10-12C H7 TEMPERATURES. ISOLATED DIURNAL THUNDERSTORMS MAY DEVELOP IF CAP CAN BE BREACHED LATER TODAY ALONG THE NUMEROUS SURFACE BOUNDARIES WHERE HEATING/CONVERGENCE WILL BECOME MAXIMIZED. MORE LIKELY REGION FOR DIURNAL DEVELOPMENT MAY BE ALONG DRY LINE INTO CENTRAL TX WHERE CLEAR SKIES WILL SUPPORT UNSEASONABLY WARM TEMPERATURES APPROACHING 100F AND ELIMINATE CAP BY 22Z. GIVEN VERY STRONG INSTABILITY AND 40-50 KT EFFECTIVE SHEAR...ANY STORM/S WHICH CAN ERUPT THIS AFTERNOON WILL BECOME SUPERCELLS QUICKLY WITH ENHANCED THREAT OF VERY LARGE HAIL AND ISOLATED TORNADOES. HOWEVER...LACK OF A LOW LEVEL JET OVER THE REGION MAY LIMIT ANY SUSTAINED TORNADO THREAT FOR MUCH OF THE DAY. APPEARS MOST LIKELY SCENARIO FOR WIDESPREAD SEVERE THUNDERSTORMS MAY EVOLVE OUT OF THE HIGH PLAINS AHEAD OF SHORTWAVE TROUGH NOW MOVING INTO THE CENTRAL ROCKIES. BOTH RUC AND GFS INDUCE WEAK PRESSURE FALLS AND SUBSEQUENT VEERING RESPONSE TO THE SURFACE WINDS OVER THE OK/TX PANHANDLES AND FAR SWRN KS. FORECAST SOUNDINGS INDICATE MODEST SURFACE-BASED INSTABILITY BY 00Z ACROSS THIS REGION ALONG WRN EDGE OF H7 THERMAL RIDGE...EVEN BEHIND CURRENT COLD FRONT...WITH 40+ KT EFFECTIVE SHEAR SUPPORTING HIGH-BASED SUPERCELLS. THIS ACTIVITY WILL LIKELY BECOME MORE INTENSE AS IT SPREADS INTO RICHER MOISTURE ACROSS WRN OK/ERN TX PANHANDLE WRAPPING AROUND LOW CENTER ALONG THE RED RIVER. STORMS SHOULD EVOLVE INTO A LARGE COMPLEX WITH VERY LARGE HAIL AND DAMAGING WINDS EWD ACROSS MUCH OF OK THROUGH THE EVENING. SHOULD ERN OK REMAIN CONVECTIVE-FREE...A VERY MOIST AIR MASS WILL SUPPORT EXTREME INSTABILITY THROUGH THE NIGHT INTO WRN AR. GFS DEEPENS A LOW CENTER FROM SOUTH OF ADM BY 03Z AND LIFTS IT NEWD INTO NWRN AR OVERNIGHT WITH SUBSEQUENT INCREASE IN SLY LLJ INTO ERN OK. THIS MAY SUPPORT A WIDESPREAD SEVERE THREAT FROM S-CENTRAL/SERN OK INTO THE OZARK REGION LATER TONIGHT INCLUDING AN INCREASED TORNADO THREAT SHOULD PRESSURE FALLS/CONVERGENCE TAP INTO RICH MARINE AIR. ...LA ACROSS THE CENTRAL GULF COAST STATES... INCREASING SLY LOW LEVEL WINDS ACROSS THE CENTRAL GULF COAST ARE EXPECTED TO LIFT WARM FRONT SLOWLY NWD TODAY AHEAD OF SHORTWAVE TROUGH NOW MOVING ACROSS TX. IN ADDITION...MODELS MAINTAIN 40-50 KT WLY MID LEVEL FLOW ATOP A VERY MOIST BOUNDARY LAYER WITH SURFACE DEW POINTS IN THE LOWER TO MID 70S. THIS SHOULD SUPPORT INCREASE IN CONVECTION THROUGH THE LATE MORNING/AFTERNOON AS HEATING PRODUCES A VERY UNSTABLE AIR MASS. RUC FORECAST SOUNDINGS BECOME VERY FAVORABLE FOR INTENSE SUPERCELLS BY LATE THIS AFTERNOON...THOUGH NAM AND GFS PRODUCE WEAKER H85 WINDS AND LESS SHEAR TODAY. REGARDLESS...EXPECT THREATS FOR SUPERCELLS AND MULTICELL CLUSTERS WILL INCREASE ACROSS THE LOWER MS RIVER VALLEY AND SPREAD/DEVELOP EWD ALONG AND NORTH OF WARM FRONT ACROSS SRN/CENTRAL MS AND SRN/WRN AL TODAY. LARGE HAIL AND DAMAGING WINDS WILL BE PRIMARY SEVERE THREATS...WITH TORNADO POTENTIAL BEING STRONGER SHOULD RUC FORECASTS VERIFY. ..EVANS/JEWELL.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 16:47:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 12:47:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 091645 SWODY1 SPC AC 091643 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1143 AM CDT TUE MAY 09 2006 VALID 091630Z - 101200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS TO THE LOWER MS VALLEY.... ...SRN/CENTRAL MS AND SW AL AREA TODAY... ELEVATED THUNDERSTORMS ARE FORMING THIS MORNING ALONG A NW-SE ORIENTED BAROCLINIC ZONE ACROSS SE MS AND SW AL. LOW-LEVEL WAA...A FEED OF STEEP MID LEVEL LAPSE RATES...AND MUCAPE IN EXCESS OF 2000 J/KG FROM THE SW IS SUPPORTING THIS CONVECTION. THE STORMS MAY GRADUALLY BECOME SURFACE BASED AS THE BOUNDARY LAYER WARMS INTO THE 80S...AND STORM COVERAGE WILL LIKELY INCREASE WITH THE APPROACH OF A MIDLEVEL SHORTWAVE TROUGH MOVING EWD FROM NRN LA TO MS. VERTICAL SHEAR AND INSTABILITY ALONG THE SURFACE BOUNDARY WILL SUPPORT SUPERCELLS WITH A THREAT FOR LARGE HAIL AND DAMAGING WINDS...AND PERHAPS AN ISOLATED TORNADO OR TWO. ...AR/WRN TN/NW MS AREA THIS AFTERNOON... AN MCS CONTINUES TO MOVE ESEWD OVER NRN AR AND SE MO...AND THIS CONVECTION IS ASSOCIATED WITH A WELL-DEVELOPED COLD POOL AND MCV. LOW-LEVEL DESTABILIZATION IN ADVANCE OF THE ONGOING CONVECTION SHOULD ALLOW FOR ADDITIONAL SEVERE STORM DEVELOPMENT THROUGH THE AFTERNOON ALONG THE LEADING EDGE OF THE COLD POOL...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE ACROSS CENTRAL/ERN AR INTO WRN TN AND NW MS THROUGH LATE AFTERNOON. ...CENTRAL/ERN OK AND NE TX THIS AFTERNOON/EVENING... AN OUTFLOW BOUNDARY /TRAILING SWWD FROM THE ONGOING AR STORMS/ IS MOVING SEWD ACROSS SE OK. THIS BOUNDARY WILL LIKELY CONTINUE SEWD ACROSS THE ARKLATEX REGION THIS AFTERNOON...WHILE THE WRN PORTION OF THE OUTFLOW SHOULD STALL ACROSS CENTRAL OK...JUST NE OF A TRIPLE POINT LOW BETWEEN FSI AND OUN. S OF THE LOW...A DRYLINE WILL BECOME BETTER DEFINED ACROSS SRN OK/N TX. THE 12Z SOUNDINGS FROM OUN/FWD SHOW VERY STEEP MID LEVEL LAPSE RATES ABOVE A MOIST BOUNDARY LAYER...AS WELL AS A STRONG CAP WITH CONVECTIVE TEMPERATURES IN THE 90S. WITH LITTLE LARGE SCALE FORCING FOR ASCENT...CONVECTIVE INITIATION WILL RELY ALMOST SOLELY ON THE COMBINED IMPACTS OF DAYTIME HEATING AND MESOSCALE LIFT ALONG THE OUTFLOW AND NEAR THE TRIPLE POINT LOW. IF STORMS CAN FORM...EXTREME INSTABILITY /MLCAPE NEAR 4000 J/KG/ AND MODEST VERTICAL SHEAR WILL SUPPORT A THREAT FOR SUPERCELLS WITH VERY LARGE HAIL...DAMAGING WINDS...AND A COUPLE OF TORNADOES. ...TX PANHANDLE/SW KS/WRN OK OVERNIGHT... A SHORTWAVE TROUGH OVER UT THIS MORNING IS FORECAST TO REACH THE SRN HIGH PLAINS TONIGHT. A MOIST UPSLOPE FLOW REGIME MAY SUPPORT THUNDERSTORM DEVELOPMENT BY LATE EVENING/EARLY TONIGHT OVER THE TX/OK PANHANDLES INTO SW KS...WITH CONVECTION EXPECTED TO GROW INTO A LARGER MCS ACROSS WRN/NWRN OK BY EARLY WEDNESDAY. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THIS ACTIVITY...ESPECIALLY AS THE STORMS ENCOUNTER GREATER INSTABILITY LATE TONIGHT ACROSS OK. ...SE FL THIS AFTERNOON... THE REMNANTS OF OVERNIGHT CONVECTION ARE MOVING SEWD FROM CENTRAL TOWARD SE FL. SOME DAYTIME HEATING PRIOR TO THE ARRIVAL OF ANVIL DEBRIS CLOUDS AND BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S TO NEAR 70 F WILL RESULT IN SUFFICIENT INSTABILITY FOR A FEW STRONG/MARGINALLY SEVERE STORMS THIS AFTERNOON. THE MORE PROBABLE AREAS FOR DEVELOPMENT WILL BE ALONG THE SE MOVING OUTFLOW BOUNDARY...AND WHERE THIS BOUNDARY INTERSECTS THE E COAST SEA BREEZE. ISOLATED DOWNBURST WINDS AND SMALL HAIL WILL BE THE MAIN THREATS. ..THOMPSON/TAYLOR.. 05/09/2006  From swody1 at goshenarc.org Tue May 9 20:10:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 16:10:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 092008 SWODY1 SPC AC 092006 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0306 PM CDT TUE MAY 09 2006 VALID 092000Z - 101200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS OK/TX AND THE LOWER MS VALLEY/TN VALLEY AND PARTS OF THE DEEP SOUTH... ...TN/MS/AL... ARC OF DEEP CONVECTION FROM SWRN KY TO NRN MS CONTINUES EAST TOWARD MIDDLE TN AND TRAILS SWWD OVER NRN MS. AIR MASS IMMEDIATELY AHEAD OF THE LINE HAS BECOME MARGINALLY UNSTABLE WITH DAYTIME HEATING. RADAR SUGGESTS THAT STORM INTENSITY ALONG THE LEADING EDGE OF THE CONVECTIVE LINE HAS CHANGED LITTLE BUT STORM MOTION WAS ONLY ABOUT 25-30KT. THERMODYNAMIC AND KINEMATIC ENVIRONMENT SHOULD CONTINUE TO SUPPORT MARGINALLY SEVERE HAIL/WIND THREAT FOR A COUPLE MORE HOURS BEFORE STORMS ENCOUNTER GREATER STABILITY SITUATED OVER ERN TN. FARTHER SOUTH...BAND OF WEAKLY ORGANIZED STORMS PERSISTS WITHIN SWATH OF LOW LEVEL WARM AIR ADVECTION FROM SRN MS TO ERN AL. THIS ACTIVITY ALSO APPEARS TO BE ENHANCED BY WEAK SRN STREAM IMPULSE DEVELOPING EWD FROM THE LOWER MS VALLEY. SUFFICIENT SPEED AND DIRECTIONAL SHEAR EXIST IN THIS REGION FOR SUPERCELLS WITH ATTENDANT THREAT FOR LARGE HAIL AND POSSIBLY ISOLATED WIND DAMAGE. SEVERE POTENTIAL SHOULD DECREASE AS ACTIVITY SPREADS EAST INTO DRIER MORE STABLE AIR MASS ACROSS ERN AL THIS EVENING. ...ERN OK/AR THIS EVENING THROUGH TONIGHT... SUBSTANTIAL CAP/INHIBITION PERSISTS FROM TX NWD ACROSS THE RED RIVER VALLEY THIS AFTERNOON BASED ON LATEST ANALYSIS AND RAOB FROM DFW. EXPECT THAT THE WARM TEMPERATURES ALOFT...COUPLED WITH LACK OF STRONGER DEEP LAYER ASCENT OVER THE REGION...MAY DELAY ONSET OF SURFACE-BASED TSTM DEVELOPMENT FROM NEAR TRIPLE-POINT LOW AND DRYLINE...EWD ALONG DECAYING OUTFLOW BOUNDARY FROM SERN OK INTO SWRN/SCNTRL AR. HOWEVER...SURFACE TEMPERATURES MAY WARM SUFFICIENTLY NEAR THESE FEATURES TO FOSTER AT LEAST ISOLATED STORM DEVELOPMENT INTO THE EARLY EVENING. STRONGEST SIGNAL FOR CONVECTIVE DEVELOPMENT FROM SHORT-TERM MODEL DATA APPEARS NEAR THE OUTFLOW/WARM FRONT OVER ERN OK/SCNTRL AR THROUGH THIS EVENING. ADDITIONAL DEVELOPMENT APPEARS POSSIBLE NEAR WEAK FRACTURED COLD FRONT OVER SWRN MO/NWRN AR. MORE UNCERTAINTY REGARDING DEVELOPMENT EXISTS SWD ALONG THE DRYLINE WHERE STRONG CAPPING SHOULD PERSIST. ANY ACTIVITY DEVELOPING ACROSS THE REGION WILL OCCUR WITHIN EXTREMELY UNSTABLE AIR MASS. WHILE DEEP LAYER SHEAR REMAINS SOMEWHAT MARGINAL BETWEEN FASTER MID LEVEL FLOW NORTH AND SOUTH...SUFFICIENT LOW LEVEL TURNING NEAR THE BOUNDARIES...IN ADDITION TO POTENTIAL FOR STRONG STRETCHING DUE TO HIGH INSTABILITY...SHOULD PROMOTE SUPERCELL STRUCTURE WITH VERY LARGE HAIL LIKELY. TORNADO AND DAMAGING WIND POTENTIAL WILL ALSO EXIST WITH ANY SUPERCELL TRACKING NEAR/ALONG OUTFLOW/WARM FRONT FEATURE FROM ERN OK INTO WRN AR THIS EVENING. STORM COVERAGE MAY INCREASE ALONG AND NORTH OF THE WARM FRONT OVER ERN OK AND AR THROUGH LATE EVENING AS LOW LEVEL JET DIRECTED INTO THESE AREAS STRENGTHENS. WIND/HAIL AND ISOLATED TORNADO POTENTIAL SHOULD SPREAD GENERALLY EWD/SEWD ACROSS AR...AND PERHAPS INTO NRN LA AND NRN MS THROUGH EARLY WEDNESDAY MORNING. ...SRN HIGH PLAINS TO OK TONIGHT... WATER VAPOR AND LATEST RUC FIELDS CONTINUE TO DEPICT A WELL-DEFINED SHORT WAVE TRACKING EAST ACROSS THE FOUR CORNERS AREA THIS AFTERNOON. THIS FEATURE...COUPLED WITH MOIST POST-FRONTAL UPSLOPE FLOW INTO THE NERN NM/SERN CO HIGH PLAINS...WILL ENHANCE HIGH PLAINS MCS DEVELOPMENT THROUGH THE EVENING. THIS SYSTEM WILL DEVELOP EWD/SEWD INTO INCREASINGLY FAVORABLE ENVIRONMENT FROM THE ERN TX PNHDL EAST ACROSS WRN OK TONIGHT. LOW LEVEL WARM AIR AND MOISTURE ADVECTION...AND DEEP LOW LEVEL ELY INFLOW TO THE NORTH OF RED RIVER TRIPLE-POINT LOW...SHOULD SUSTAIN THE CONVECTIVE COMPLEX. OVERALL PATTERN APPEARS TO SUGGEST A SEVERE MCS WITH DAMAGING WINDS AND HAIL SPREADING EAST INTO CNTRL OK THROUGH EARLY WEDNESDAY MORNING. ..CARBIN.. 05/09/2006  From swody1 at goshenarc.org Wed May 10 01:13:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 09 May 2006 21:13:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100109 SWODY1 SPC AC 100107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT TUE MAY 09 2006 VALID 100100Z - 101200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS SERN OK...WRN AND INTO CENTRAL AR...AND NERN TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS AND INTO THE CENTRAL GULF COAST REGION... ...SRN PLAINS... TWO SEPARATE CLUSTERS OF SEVERE/SUPERCELL STORMS ARE ONGOING ATTM...ONE ACROSS ERN PORTIONS OF THE TX PANHANDLE AHEAD OF UPPER TROUGH AND THE OTHER OVER SERN OK AND NNEWD INTO SRN MO/NRN AR ALONG COLD FRONT. VERY UNSTABLE AIRMASS IS IN PLACE ACROSS SERN OK AND ADJACENT N CENTRAL AND NERN TX/WRN AR...WHERE 4000 TO 5000 J/KG MEAN-LAYER CAPE IS INDICATED. WITH 40 TO 45 KT WLY MID-LEVEL FLOW ABOVE INCREASING/VEERING LOW-LEVEL WINDS...SHEAR IS SUPPORTIVE OF SUPERCELLS -- AND ATTENDANT THREAT FOR VERY LARGE HAIL AND DAMAGING WINDS ALONG WITH ISOLATED TORNADOES. EXPECT STORMS TO INCREASE AS LOW-LEVEL JET DEVELOPS...AND WILL SPREAD EWD/SEWD ACROSS AR/NERN TX AND LIKELY INTO PARTS OF LA/MS BY THE END OF THE PERIOD -- ACCOMPANIED BY A CONTINUED THREAT FOR SEVERE WEATHER. MEANWHILE...EXPECT STORMS OVER THE TX PANHANDLE TO CONTINUE SPREADING EWD INTO WRN OK/N TX OVER THE NEXT SEVERAL HOURS. THOUGH STORMS ARE MAINLY N OF THE COLD FRONT...SUFFICIENT HEATING N OF BOUNDARY HAS RESULTED IN SURFACE-BASED CAPE 1500 TO 3000 J/KG. WITH SUFFICIENTLY STRONG/FAVORABLY-VEERING DEEP-LAYER WIND FIELD...EXPECT THREAT FOR LARGE HAIL AND LOCALLY-DAMAGING WINDS ALONG WITH AN ISOLATED TORNADO TO CONTINUE AS STORMS ENCOUNTER MORE STABLE AIR WITH EWD EXTENT. STORMS WILL LIKELY ROLL THROUGH THE OVERNIGHT HOURS...ALONG WITH A CONTINUED SEVERE THREAT. ...CENTRAL GULF COAST REGION... THUNDERSTORMS HAVE WEAKENED ACROSS NRN AL AS THEY HAVE ENCOUNTERED MUCH MORE STABLE AIRMASS. HOWEVER...STRONG/SEVERE STORMS CONTINUE OVER SERN MS/SRN AL WHERE MOIST/MODERATELY-UNSTABLE BOUNDARY LAYER REMAINS. EVENING LIX /SLIDELL LA/ RAOB INDICATES DEEP-LAYER WIND PROFILE SUPPORTIVE OF SEVERE STORMS...WHICH COMBINED WITH FAVORABLE AIRMASS SUGGESTS THAT THREAT FOR HAIL AND LOCALLY DAMAGING WINDS WILL PERSIST/SPREAD SEWD INTO THE FL PANHANDLE OVER THE NEXT SEVERAL HOURS. ...MID/UPPER MS VALLEY... LIMITED/LINGERING SEVERE THREAT SHOULD WANE THROUGH THIS EVENING AS BOUNDARY LAYER SLOWLY STABILIZES. A FEW STRONGER STORMS MAY STILL PRODUCE BRIEF GUSTY WINDS OR MARGINAL HAIL FOR THE NEXT COUPLE OF HOURS. ..GOSS.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 06:11:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 02:11:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100608 SWODY1 SPC AC 100607 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0107 AM CDT WED MAY 10 2006 VALID 101200Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS WRN KY...WRN AND MIDDLE TN...ERN AR...NERN LA...MUCH OF MS...AND NRN AND WRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MIDWEST STATES SWD ACROSS THE OH/TN /MS VALLEYS TO THE GULF COAST... ...SYNOPSIS... MID-LEVEL SHORT-WAVE TROUGH MOVING ACROSS KS/OK/TX AT THE START OF THE PERIOD WILL MOVE RAPIDLY EWD ACROSS MO/AR THROUGH THE DAY. THIS FEATURE WILL EVENTUALLY BECOME ABSORBED BY LARGER TROUGH DIGGING SWD INTO THE PLAINS. BY THE END OF THE PERIOD...A LARGE CLOSED LOW IS FORECAST ACROSS THE MID MS/LOWER OH VALLEY REGION -- WITHIN LARGE TROUGH COVERING THE ENTIRE CENTRAL CONUS. AT THE SURFACE...COLD FRONT IS INITIALLY FORECAST TO EXTEND FROM ERN WI SWD ACROSS IL...AND THEN SWWD ACROSS SERN MO/NWRN AR AND INTO NRN AND WRN TX. A LOW FORECAST ALONG THIS FRONT OVER NERN TX AT THE START OF THE PERIOD SHOULD DEEPEN AND MOVE NEWD TO THE MID MS/LOWER OH VALLEY BY LATE AFTERNOON/EARLY EVENING...WITH THE COLD FRONT EXTENDING SWWD ACROSS WRN TN/NWRN MS/LA AND INTO THE TX COASTAL REGION. OVERNIGHT...THIS LOW SHOULD DEEPEN RAPIDLY AND MOVE NWD INTO NRN INDIANA/LOWER MI BY THE END OF THE PERIOD...WITH COLD FRONT ARCING SEWD ACROSS OH...SWD ALONG THE SRN APPALACHIANS...AND THEN SWWD INTO THE CENTRAL GULF OF MEXICO. ...ERN TX EWD ACROSS THE MS/OH/TN VALLEYS AND GULF COAST REGION... VERY COMPLEX BUT POTENTIALLY SIGNIFICANT SEVERE WEATHER EVENT IS ANTICIPATED THIS PERIOD...WITH WIDESPREAD ONGOING CONVECTION ACROSS MUCH OF THE RISK AREA COMPLICATING THE SCENARIO. DEGREE OF DESTABILIZATION OVER THE NRN HALF OF THE OUTLOOK AREA -- I.E. ACROSS THE TN AND OH VALLEY REGION -- IS DIFFICULT TO DISCERN AS A RESULT OF THE ONGOING CLOUDS/PRECIPITATION. FROM A LARGE-SCALE PERSPECTIVE...A STRENGTHENING MID-LEVEL TROUGH -- ACCOMPANIED BY A STRONG /70 TO 90 KT/ MID-LEVEL JET STREAK -- WILL SPREAD EWD ALONG WITH INTENSIFYING ATTENDANT COLD FRONT. WARM SECTOR AIRMASS FEATURING LOW TO MID 60S DEWPOINTS N OF THE TN VALLEY AND LOW TO MID 70S ACROSS THE GULF COAST STATES WILL BE IN PLACE AHEAD OF COLD FRONT -- THOUGH AGAIN...THE DEGREE OF DESTABILIZATION FROM THE MID MS/TN VALLEYS NWD REMAINS IN QUESTION. NONETHELESS...STRENGTH OF UPPER SYSTEM AND ASSOCIATED WIND FIELD SPREADING ACROSS MOIST BOUNDARY LAYER SUGGESTS THE POTENTIAL FOR A WIDESPREAD SIGNIFICIANT SEVERE WEATHER EPISODE. AS FRONT MOVES EWD...EXPECT STORMS TO CONTINUE/SPREAD EWD THROUGH THE AFTERNOON ACROSS THE MID MS/TN VALLEYS. NEW STORM DEVELOPMENT SHOULD OCCUR SWD ALONG FRONT ACROSS LA AND INTO ERN/SERN TX. STRONG WIND FIELD WILL YIELD SHEAR FAVORABLE FOR SEVERE/SUPERCELL STORMS...WITH STORMS EXPECTED TO RAPIDLY BECOME SEVERE. FURTHER N...ONGOING CONVECTION SHOULD INTENSIFY AS UPPER SYSTEM AND ASSOCIATED SURFACE FRONT STRENGTHEN. STORMS SHOULD ALSO DEVELOP NWD ALONG FRONT ACROSS IL INTO THE GREAT LAKES REGION...THOUGH LESS UNSTABLE AIRMASS AND SOMEWHAT WEAKER WIND FIELD SUGGESTS A LESS SIGNIFICANT SEVERE THREAT. GIVEN DEGREE OF INSTABILITY EXPECTED ACROSS SRN PORTIONS OF THE OUTLOOK -- ...EXPECT VERY LARGE HAIL TO BE THE MAIN SEVERE THREAT...ALONG WITH DAMAGING WINDS AND ISOLATED TORNADOES. GREATEST TORNADO THREAT -- INCLUDING THE POTENTIAL FOR A COUPLE STRONG/DAMAGING TORNADOES -- APPEARS TO EXIST ACROSS THE NRN HALF OF MS AND INTO WRN AND MIDDLE TN. DEPENDING UPON DEGREE OF HEATING/DESTABILIZATION WHICH CAN OCCUR NWD INTO THE OH VALLEY...THREAT MAY EXTEND FURTHER N THAN CURRENTLY ANTICIPATED. STORMS WILL CONTINUE EWD OVERNIGHT...CROSSING THE OH/TN VALLEYS AND MOVING INTO THE APPALACHIANS. ATTM...IT APPEARS THAT SEVERE THREAT SHOULD DIMINISH WITH TIME DURING THE OVERNIGHT HOURS...AND SHOULD NOT EXTEND E OF THE MOUNTAINS. HOWEVER...LIMITED THREAT MAY SPREAD EWD ACROSS GA...AND POSSIBLY INTO SC BY THE END OF THE PERIOD. ..GOSS.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 12:34:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 08:34:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101231 SWODY1 SPC AC 101230 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0730 AM CDT WED MAY 10 2006 VALID 101300Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS FROM LA/MS INTO SWRN KY... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM THE UPPER TX COAST INTO THE OH VALLEY... ...TORNADOES...A FEW STRONG ARE POSSIBLE ACROSS PORTIONS OF THE GULF STATES INTO THE TN VALLEY... A SIGNIFICANT SEVERE WEATHER EVENT IS EXPECTED TO EVOLVE ACROSS THE LOWER MS VALLEY AND CNTRL GULF STATES...NWD ACROSS PORTIONS OF THE TN VALLEY TODAY. TORNADOES...POTENTIALLY STRONG...DAMAGING WINDS AND VERY LARGE HAIL ARE ALSO POSSIBLE PRIOR TO COLD FRONTAL PASSAGE. THREE MCS CLUSTERS ARE ONGOING EARLY THIS MORNING FROM THE RED RIVER REGION OF SRN OK/NCNTRL TX...EAST ACROSS AR...AND ANOTHER INTO CNTRL AL. THIS EARLY ACTIVITY WILL PLAY AN IMPORTANT ROLE IN FUTURE DEVELOPMENT/STORM MODE AS BOUNDARY LAYER WARMS TO THE SOUTH OF CONVECTIVE OUTFLOWS. OVERNIGHT TRENDS REMAIN SUPPORTIVE OF EARLIER OUTLOOK...ALTHOUGH CONFIDENCE IN TORNADIC SUPERCELLS HAS RISEN ACROSS MS INTO NRN AL. THIS ZONE OF HEIGHTENED INTEREST IS PARTIALLY DUE TO THE INFLUENCE OF OVERNIGHT MCS THAT HAS BACKED LOW LEVEL FLOW TO THE NORTH OF ASSOCIATED OUTFLOW BOUNDARY. THIS WILL MAINTAIN HIGH HELICITY ENVIRONMENT WITHIN STRONGEST ZONE OF LOW LEVEL WARM ADVECTION WHERE SUPERCELL THUNDERSTORM DEVELOPMENT IS EXPECTED BY EARLY AFTERNOON. THERE IS SOME CONCERN THAT AFOREMENTIONED MCS CLUSTERS COULD HINDER DISCRETE DEVELOPMENT ACROSS FAR NRN PORTIONS OF MODERATE RISK...HOWEVER SIGNIFICANT CAP ACROSS SERN TX/LA WILL PREVENT SWD DEVELOPMENT THROUGH MID-LATE MORNING. AS A RESULT...VERY UNSTABLE AIR MASS WILL SPREAD NEWD...RETURNING ATOP STRONGLY SHEARED BUT LESS CAPPED REGION OF THE NCNTRL GULF STATES. CURRENT THINKING IS STRONGEST FORCED CONVECTION ALONG COLD FRONT WILL MAINTAIN N-S LINEAR STRUCTURE AS IT ADVANCES EWD ALONG THE RED RIVER OF SRN OK/NERN TX. THIS ACTIVITY SHOULD GRADUALLY EXPAND IN AREAL COVERAGE...POSSIBLY OVERTAKING DOWNSTREAM CONVECTION OVER AR BY MID-LATE MORNING. AN EVER EXPANDING MCS MAY EVOLVE FROM THIS INTERACTION WITH NEWD DEVELOPMENT INTO THE WRN PORTIONS OF THE TN VALLEY AS SFC LOW LIFTS NEWD. DOWNSTREAM...BOUNDARY LAYER HEATING/MOISTENING ATOP MODIFYING OUTFLOW AIR MASS OVER MS/AL SHOULD ALLOW FOR MORE DISCRETE SUPERCELL STRUCTURES TO DEVELOP. FORECAST SOUNDINGS FOR THIS REGION...PARTICULARLY FROM THE 09Z RUC...STRONGLY FAVOR TORNADIC DEVELOPMENT AS CELL MOTION UTILIZES HIGHER HELICITY ENVIRONMENT. OTHER STORMS WILL ALSO DEVELOP ACROSS THE WARM SECTOR AHEAD OF THE COLD FRONT AS IT ADVANCES EWD INTO LA. VERY STEEP LAPSE RATES AND EXTREME SBCAPE...IN EXCESS OF 5000 J/KG...WILL AID IN VERY LARGE HAIL DEVELOPMENT...AS WELL AS ENHANCE DAMAGING WIND POTENTIAL. MULTIPLE STORM MODES APPEAR LIKELY ACROSS THE MODERATE RISK REGION...WITH WIDESPREAD SEVERE CONSISTING OF TORNADOES...DAMAGING HAIL...AND INTENSE WIND. FRONTAL PASSAGE LATE TONIGHT WILL END SEVERE THREAT FROM WEST TO EAST. ..DARROW/LEVIT.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 16:36:48 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 12:36:48 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101634 SWODY1 SPC AC 101632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT WED MAY 10 2006 VALID 101630Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF EXTREME SERN AR...NERN LA...CENTRAL AND SRN MS...CENTRAL AND SRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GULF COASTAL STATES NWD ACROSS THE MS/TN AND OH VALLEY REGION... ...TORNADOES...A FEW STRONG..ARE POSSIBLE ACROSS PORTIONS OF THE CENTRAL GULF STATES THIS AFTERNOON AND EVENING ACROSS THE SOUTH CENTRAL GULF COAST STATES... UPPER TROUGH OVER THE CENTRAL PLAINS WILL DEEPEN AND SHIFT EWD INTO MID MS/OH VALLEYS TONIGHT. A COLD FRONT WILL SWEEP RAPIDLY THROUGH THE MS VALLEY REGION TODAY AND INTO THE OH/TN VALLEYS AND CENTRAL GULF REGION TONIGHT. A WEAK LOW ALONG THE FRONT IS FORECAST TO DEEPEN OVER THE OHIO VALLEY TONIGHT. LOWER/MID MS VALLEY EWD THROUGH THE CENTRAL GULF COASTAL STATES AND TN VALLEY... THREE MCS CLUSTERS WERE LOCATED FROM AL TO AR THIS MORNING. THE LEADING CLUSTER WAS WEAKENING IN SRN AL...THE SECOND ONE WAS MOVING THROUGH NRN MS INTO NWRN AL...AND THE THIRD AND MOST INTENSE CLUSTER WAS MOVING THROUGH SRN/CENTRAL AR. A BOUNDARY... SEPARATING RAIN COOLED AIR TO THE NORTH AND A WARM SECTOR TO THE SOUTH WITH MLCAPES IN EXCESS OF 3000 J/KG...EXTENDED FROM SERN AR ESEWD ACROSS CENTRAL MS INTO SWRN AL. ALTHOUGH THE AIR MASS ACROSS THE WARM SECTOR IS CURRENTLY CAPPED...STRONG FORCING AND 50-60 KT DEEP LAYER SHEAR HAS RESULTED IN INTENSE STORMS/SUPERCELLS WITHIN THE AR THUNDERSTORM LINE. WITH ADDITIONAL HEATING AND INCREASING LARGE SCALE LIFT...IN RESPONSE TO SHORTWAVE TROUGH MOVING EWD OUT OF OK...STORMS ARE LIKELY TO BECOME ROOTED IN THE BOUNDARY LAYER AND TAP INTO THE STRONG INSTABILITY. THE DEGREE OF INSTABILITY... DEEP LAYER SHEAR AND 30-40 KT 1 KM SHEAR...WILL FAVOR INTENSE SUPERCELLS WITH THE POTENTIAL FOR VERY DAMAGING WINDS...LARGE HAIL AND STRONG TORNADOES ACROSS THE MODERATE RISK AREA THIS AFTERNOON/EVENING. THE MORNING MCS CLUSTERS RESULTED IN EXTENSIVE CLOUDS AND A RAIN COOLED BOUNDARY LAYER SURROUNDING THE TN VALLEY. THIS WILL LIMIT THE NWD EXTENT OF THE STRONGER INSTABILITY ACROSS PORTIONS OF NRN MS/AL NWD INTO SRN KY. THOUGH SCATTERED SEVERE STORMS ARE EXPECTED TO DEVELOP ACROSS THESE AREAS THIS AFTERNOON AS THE UPPER TROUGH AND ASSOCIATED COLD FRONT APPROACHES FROM THE WEST...THE COOL BOUNDARY LAYER SHOULD RESULT IN MOSTLY ELEVATED STORMS WITH MAINLY A SEVERE HAIL AND WIND THREAT. ...OH VALLEY... A LARGE CLOUD SHIELD AND SOME PRECIPITATION WILL SPREAD NWD ACROSS THE REGION THROUGHOUT THE AFTERNOON AND INHIBIT STRONG STORM DEVELOPMENT THROUGH MOST OF THE DAY. HOWEVER...AS THE UPPER TROUGH APPROACHES ALONG WITH A 70 KT MID LEVEL WIND MAX...SURFACE LOW IS FORECAST TO MOVE FROM SRN INDIANA NWD INTO WRN OH AND DEEPEN. ALTHOUGH INSTABILITY WILL BE WEAK DUE TO DEEP MOIST VERTICAL PROFILES...BACKING BOUNDARY LAYER WINDS AND STRENGTHENING WINDS ALOFT WILL BECOME MORE FAVORABLE FOR SUPERCELLS AND TORNADOES. THE BIGGEST CONCERN ABOUT A HIGHER RISK ATTM IS THE CURRENT FORECAST OF POOR LAPSE RATES. HOWEVER...THE WIND PROFILES AND PRESSURE FALLS MAY SUPPORT A TORNADO TREAT ACROSS PORTIONS OF INDIANA AND OH OVERNIGHT. ...SERN MO AND SRN IL... AS ONE SHORTWAVE TROUGH LIFTS NEWD ACROSS THE REGION THIS AFTERNOON...SOME HEATING MAY AID IN THE DEVELOPMENT OF STRONGER STORMS ALONG AND AHEAD OF THE COLD FRONT. THE BOUNDARY LAYER SHOULD REMAIN RELATIVELY COOL...BUT 30-40 KT DEEP LAYER SHEAR AND MLCAPES UP TO 1000 J/KG WILL SUPPORT SOME STORMS WITH SEVERE HAIL/WIND. ..IMY.. 05/10/2006  From swody1 at goshenarc.org Wed May 10 20:08:15 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 10 May 2006 16:08:15 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 102003 SWODY1 SPC AC 102001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT WED MAY 10 2006 VALID 102000Z - 111200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER MS VALLEY FROM NERN LA...OVER SCNTRL MS AND SWRN AL... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE TX GULF COAST ACROSS THE LOWER OH VALLEY TO LOWER MI... ...SYNOPSIS... COMPLEX AND POTENTIALLY VOLATILE SEVERE WEATHER SITUATION NOW UNFOLDING ACROSS THE LOWER MS VALLEY AND DEEP SOUTH. ADDITIONALLY...SEVERE STORM POTENTIAL IS EXPECTED TO INCREASE ACROSS PARTS OF THE LOWER OH VALLEY AND MIDWEST FROM LATE THIS AFTERNOON INTO THE EVENING. STRONG DYNAMIC FORCING ASSOCIATED WITH A POTENT SHORT WAVE TROUGH AND 70KT MID LEVEL WIND MAX WILL CONTINUE TO OVERSPREAD VERY UNSTABLE AIR MASS ACROSS PARTS OF LA...MS...AL...AND THE FL PANHANDLE OVER THE NEXT FEW HOURS. AS THE MID/UPPER LEVEL SYSTEM SWINGS EWD/NEWD ACROSS THESE AREAS...RAPID SURFACE CYCLOGENESIS WILL OCCUR ALONG A STRENGTHENING FRONTAL ZONE SITUATED FROM LAKE MI SWD TO THE CONFLUENCE OF THE OH/MS RIVERS. THE SURFACE LOW WILL DEEPEN RAPIDLY TONIGHT WHILE TRACKING INTO SRN LOWER MI. THE COLD FRONT ASSOCIATED WITH THIS CYCLONE WILL ACCELERATE ESEWD ACROSS THE MID/LOWER MS VALLEY THROUGH LATE THIS EVENING. ...LA...SRN MS/AL...WRN FL PNHDL... OUTFLOW FROM A PAIR OF MATURE MESOSCALE CONVECTIVE SYSTEMS CROSSING NRN MS/AL HAS STRONGLY REINFORCED FRONTAL ZONE/WARM FRONT SITUATED FROM NERN LA EWD TO SWRN AL. MEANWHILE...COLD FRONT WAS ADVANCING EAST AND INTERSECTS THE WRN EXTENSION OF THE WARM FRONT ACROSS NRN LA. AIR MASS AHEAD OF AND ALONG THESE BOUNDARIES HAS BECOME EXTREMELY UNSTABLE WITH LATEST DIAGNOSTIC DATA INDICATING MLCAPE AROUND 3000 J/KG. MESOSCALE FORCING/ASCENT NEAR THE FRONTS...IN COMBINATION WITH DIURNAL HEATING...WILL CONTINUE TO PROMOTE SURFACE-BASED TSTM DEVELOP ACROSS THE WARM SECTOR THROUGH THIS EVENING. THIS ACTIVITY WILL OCCUR ALONG THE SRN EDGE OF THE FASTER MID LEVEL TROPOSPHERIC FLOW...AND WITHIN A KINEMATIC ENVIRONMENT CHARACTERIZED BY PRIMARILY UNIDIRECTIONAL SHEAR SUPPORTIVE OF SUPERCELLS. IN ADDITION TO VERY LARGE HAIL AND HIGH WINDS WITH THIS CONVECTION...A FEW TORNADOES WILL ALSO BE POSSIBLE...ESPECIALLY FROM DISCRETE CELLS TRACKING NEAR/ALONG THE OUTFLOW-REINFORCED BOUNDARY FROM ERN LA ACROSS SCNTRL MS AND INTO SWRN AL OVER THE NEXT SEVERAL HOURS. ...TX GULF COAST... COLD FRONT WILL CONTINUE TO DEVELOP SEWD INTO STRONG TO EXTREME INSTABILITY ALONG THE TX COAST FROM BRO THROUGH HOU. ALTHOUGH LACK OF STRONGER LARGE SCALE FORCING AND STRONG CAP MAY INHIBIT CONVECTIVE DEVELOPMENT WITH SWD/SWWD EXTENT ALONG THE FRONT... LATEST SHORT-TERM GUIDANCE INDICATES AT LEAST SCATTERED STRONG TO SEVERE STORM DEVELOPMENT COULD OCCUR AS THE BOUNDARY MOVES ACROSS THE COASTAL PLAIN...AND EVEN INTO DEEP SOUTH TX...THROUGH THE EVENING. VERY LARGE HAIL...WIND DAMAGE...AND A COUPLE OF TORNADOES APPEAR POSSIBLE WITH THIS ACTIVITY GIVEN MORE THAN ADEQUATE DEEP LAYER SHEAR FOR UPDRAFT ROTATION/ORGANIZATION. ...NERN AR/SERN MO NEWD ACROSS THE MIDWEST TO LOWER MI... VERY COMPLICATED FORECAST SCENARIO ACROSS THESE AREAS THROUGH THIS EVENING. AIR MASS DESTABILIZATION HAS BEEN STRONGLY HINDERED BY THE PASSAGE OF A SERIES OF STORM COMPLEXES FARTHER SOUTH AND EAST. WEAK AIR MASS RECOVERY WAS NOW UNDERWAY ACROSS AR/SERN MO AND GRADUAL DESTABILIZATION MAY OCCUR COINCIDENT WITH CYCLOGENESIS OVER THE LOWER OH VALLEY THROUGH LATE AFTERNOON. ANOTHER POCKET OF WEAK INSTABILITY EXISTS ACROSS NRN IL/IND AND INTO LOWER MI WHERE MARGINAL HEATING HAS CONTRIBUTED TO WEAKLY CAPPED MLCAPE AROUND 500 J/KG. TSTMS WERE DEVELOPING ACROSS THESE AREAS AS STRENGTHENING LARGE SCALE FORCING FOR ASCENT BEGINS TO ACT ON THE MARGINALLY UNSTABLE AIR MASS. STRONG DYNAMICS ASSOCIATED WITH RAPID HEIGHT FALLS AND INTENSIFYING MID LEVEL WINDS WILL LIKELY RESULT IN AN INCREASINGLY FAVORABLE ENVIRONMENT FOR ROTATING STORMS THROUGH THIS EVENING. ENHANCED LOW LEVEL SHEAR AND HIGH BOUNDARY LAYER RH NEAR THE DEEPENING SURFACE LOW COULD LEAD TO AN INCREASING POSSIBILITY OF TORNADOES IF SUFFICIENT INSTABILITY CAN DEVELOP TO MAINTAIN MODEST TO STRONG STORM UPDRAFTS. AREAS FROM THE LOWER OH RIVER VALLEY... NWD INTO LOWER MI...WILL NEED TO BE MONITORED CLOSELY FOR STORM EVOLUTION THROUGH THE EVENING. CURRENTLY...LIMITED INSTABILITY AND UNCERTAINTIES REGARDING AIR MASS RECOVERY SUGGEST MAINTAINING RELATIVELY LOW SEVERE WEATHER/TORNADO PROBABILITIES OVER THE REGION. ..CARBIN.. 05/10/2006  From swody1 at goshenarc.org Fri May 12 00:34:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 11 May 2006 20:34:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 120031 SWODY1 SPC AC 120029 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 PM CDT THU MAY 11 2006 VALID 120100Z - 121200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN NC THROUGH EARN PARTS OF THE MID ATLANTIC AREA... ...ERN NC THROUGH ERN VA...MD AND SERN PA... EARLY THIS EVENING A COLD FRONT EXTENDS FROM SERN GA NWD THROUGH CNTRL NC TO A SURFACE LOW IN N CNTRL VA. THIS BOUNDARY THEN EXTENDS NWWD AS AN OCCLUDED FRONT THROUGH PA AND NWWD INTO THE GREAT LAKES. THE PRE-FRONTAL WARM SECTOR IS ONLY MARGINALLY UNSTABLE WITH MLCAPE FROM 500 TO 1000 J/KG OWING TO WIDESPREAD CLOUDS AND MODEST LAPSE RATES. THIS CONTINUES TO BE THE MAIN LIMITING FACTOR FOR A MORE ROBUST SEVERE THREAT. BAND OF PRE-FRONTAL STORMS EXTENDS FROM NERN NC THROUGH ERN VA...N CNTRL MD AND INTO SERN PA. A 40+ KT LOW LEVEL JET EXISTS OVER ERN VA INTO ERN PA WITHIN ZONE OF LARGE SCALE ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH EJECTING NEWD THROUGH THE MID ATLANTIC. THE STRONG LOW LEVEL JET AND MID-UPPER LEVEL WIND FIELDS ACCOMPANYING THE SHORTWAVE TROUGH ARE RESULTING IN FAVORABLE SHEAR PROFILES FOR A FEW EMBEDDED SUPERCELLS WITHIN THE CONVECTIVE BAND. THREATS FOR ISOLATED TORNADOES AS WELL AS DAMAGING WIND ARE EXPECTED TO PERSIST INTO THE MID EVENING FROM EXTREME ERN VA INTO MD AND POSSIBLY DEL AS ACTIVITY SHIFTS EWD. THREAT SHOULD DIMINISH LATER THIS EVENING AS BOUNDARY LAYER COOLS AND AS ONGOING ACTIVITY MOVES OFFSHORE. THE STRONGER LOW LEVEL JET WILL GRADUALLY SHIFT NWD INTO THE NERN STATES AWAY FROM THE WARM SECTOR. LIMITED INSTABILITY IN THIS REGION SHOULD PRECLUDE ANY ADDITIONAL SEVERE THREAT. ..DIAL.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 05:17:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 01:17:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 120514 SWODY1 SPC AC 120512 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1212 AM CDT FRI MAY 12 2006 VALID 121200Z - 131200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THIS PERIOD WITH A LARGE UPPER LOW CENTERED OVER THE GREAT LAKES REGION ALONG WITH SHORTWAVE RIDGING OVER THE ROCKIES. A SERIES OF SHORTWAVE TROUGHS WILL MOVE ALONG THE NWRN PERIPHERY OF THE UPPER RIDGE AND THROUGH THE PACIFIC NW. ...MID ATLANTIC THROUGH NERN STATES... A SERIES OF VORTICITY MAXIMA ROTATING THROUGH UPPER LOW AND STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH COLD AIR ALOFT WILL MAINTAIN A THREAT FOR ISOLATED THUNDERSTORMS FROM PARTS OF VA NWD INTO THE MID ATLANTIC. THUNDERSTORMS WILL BE MOST LIKELY DURING AFTERNOON AS HEATING DESTABILIZES THE BOUNDARY LAYER. LIMITED INSTABILITY AND LOW LEVEL MOISTURE SUGGEST LIGHTNING ACTIVITY SHOULD REMAIN ISOLATED AND WILL DIMINISH WITH LOSS OF HEATING. ...LOWER MS VALLEY AREA... SWLY LOW LEVEL JET WILL STRENGTHEN OVERNIGHT INTO THE LOWER MS VALLEY AS SURFACE RIDGE AXIS SHIFTS EWD. LIMITED BOUNDARY LAYER MOISTURE WILL EXIST ABOVE A PLUME OF STEEP MID LEVEL LAPSE RATES...RESULTING IN MUCAPE GENERALLY BELOW 500 J/KG. A FEW STORMS MAY DEVELOP WITHIN THE WARM ADVECTION REGIME FRIDAY NIGHT...BUT EXPECTED WEAK INSTABILITY WILL LIMIT ANY POTENTIAL SEVERE THREAT. ...SRN FL... A FEW STORMS WILL REMAIN POSSIBLE ALONG AND S OF COLD FRONT INTO THE EARLY AFTERNOON ACROSS PARTS OF SRN FL. AN ISOLATED STORM OR TWO COULD PRODUCE STRONG GUSTY WINDS. WEAK MID LEVEL LAPSE RATES AND MODEST VERTICAL SHEAR SUGGEST OVERALL SEVERE POTENTIAL WILL REMAIN LIMITED. ...MT... A COLD FRONT WILL MOVE EWD THROUGH MT DURING THE DAY AS A SHORTWAVE TROUGH ADVANCES EWD THROUGH SWRN CANADA. VERY MARGINAL INSTABILITY WILL BE POSSIBLE IN ADVANCE OF EWD MOVING COLD FRONT. A FEW HIGH BASED STORMS MAY DEVELOP BY LATE AFTERNOON INTO THE EARLY EVENING OVER THE HIGHER TERRAIN OF MT AS WELL AS ALONG AND AHEAD OF EWD ADVANCING COLD FRONT. ACTIVITY SHOULD DIMINISH BY EARLY EVENING AS THE BOUNDARY LAYER COOLS. ..DIAL/BRIGHT.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 12:49:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 08:49:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121246 SWODY1 SPC AC 121244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT FRI MAY 12 2006 VALID 121300Z - 131200Z ...NO SVR TSTM AREAS FORECAST... LARGE CLOSED UPPER LOW OVER THE GREAT LAKES REGION WILL MAINTAIN RELATIVELY DRY/STABLE CONDITIONS ACROSS THE PLAINS AND GULF COAST STATES TODAY. A FEW SMALL REGIONS WILL MAINTAIN A RISK OF THUNDERSTORMS TODAY...BUT WEAK CAPE VALUES WILL LIMIT THE POTENTIAL OF SEVERE STORMS. ...SOUTH FL... SURFACE COLD FRONT IS SAGGING SOUTHWARD ACROSS THE FL PENINSULA TODAY...WITH A LINE OF SCATTERED THUNDERSTORMS CURRENTLY OVER SOUTH FL. THIS ACTIVITY IS EXPECTED TO CONTINUE TRACKING SOUTHWARD AND OFFSHORE BY MIDDAY. VERTICAL SHEAR PROFILES ARE FAVORABLE FOR ORGANIZED/SEVERE STORMS...BUT WEAK CAPE AND UNFAVORABLE TIMING SUGGEST THREAT DOES NOT WARRANT SEVERE PROBABILITIES. ...NY... RELATIVELY COLD TEMPERATURES ALOFT ARE EXPECTED TODAY ACROSS PARTS OF NY AND SOUTHERN NEW ENGLAND. FORECAST SOUNDINGS AND VISIBLE SATELLITE TRENDS IN THIS AREA SUGGEST SUBSTANTIAL DAYTIME HEATING WILL OCCUR THIS AFTERNOON. HOWEVER...LIMITED MOISTURE CONTENT OF AIR MASS SHOULD PRECLUDE THE DEVELOPMENT OF STRONG/SEVERE STORMS. ...MT... MORNING WATER VAPOR IMAGERY SHOWS SHORTWAVE TROUGH OVER WESTERN MT. THIS FEATURE WILL TRACK EASTWARD INTO THE ADJACENT HIGH PLAINS THIS AFTERNOON AND EVENING. STEEP LAPSE RATES AND MARGINAL INSTABILITY ARE EXPECTED TO DEVELOP OVER CENTRAL MT. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BY LATE AFTERNOON AND EARLY EVENING. NO SEVERE STORMS ARE FORECAST AT THIS TIME. ...OK/AR/MS.. MODELS TAKE SHORTWAVE TROUGH NOW OVER NM/WEST TX EASTWARD AND DE-AMPLIFY IT OVER TX THIS EVENING. MEANWHILE...WESTERLY/NORTHERLY SURFACE WINDS WILL PERSIST IN THIS REGION. LITTLE IN THE WAY OF LOW LEVEL MOISTENING IS EXPECTED...LIMITING DESTABILIZATION AND OVERALL SEVERE THREAT. ISOLATED THUNDERSTORMS ARE POSSIBLE AFTER DARK IN THIS AREA...BUT THREAT OF SEVERE STORMS IS RATHER LOW. ..HART.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 16:20:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 12:20:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121610 SWODY1 SPC AC 121608 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1108 AM CDT FRI MAY 12 2006 VALID 121630Z - 131200Z ...NO SVR TSTM AREAS FORECAST... LARGE AND UNSEASONABLY COOL SURFACE AND UPPER AIR CYCLONE WESTERN GREAT LAKES CONTINUES TO DOMINATE THE EASTERN TWO-THIRDS OF THE CONUS. COLD FRONT CURRENTLY PASSING THRU S FL WITH A RELATIVELY STABLE AIR MASS IN ITS WAKE OVER MUCH OF THE COUNTRY E OF ROCKIES. A WEAK TROUGH IN THE WSWLY FLOW ACROSS PAC NW AND NRN ROCKIES WILL PROVIDE SOME SUPPORT FOR HIGH BASED CONVECTION THIS AFTERNOON AND EVENING NRN ROCKIES. WHILE MOISTURE IS LIMITED THE STEEP LAPSE RATES IN PLACE AND STRONG HEATING WILL BE SUFFICIENT FOR A FEW THUNDERSTORMS ACROSS CENTRAL/ERN MT. AS PRESSURES FALL SRN HIGH PLAINS AND LOW LEVEL FLOW BACKS TO SLY ACROSS TX...SOME LOW LEVEL MOISTURE WILL BEGIN RETURNING...PARTICULARLY TONIGHT. WARM ADVECTION IN CONJUNCTION WITH EXPECTED STEEP LAPSE RATES COULD LEAD TO A FEW THUNDERSTORMS DEVELOPING MAINLY AFTER 06Z PARTS OF THE LOWER MS VALLEY. ..HALES/GRAMS.. 05/12/2006  From swody1 at goshenarc.org Fri May 12 19:58:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 12 May 2006 15:58:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121956 SWODY1 SPC AC 121954 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0254 PM CDT FRI MAY 12 2006 VALID 122000Z - 131200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... DRY/STABLE AIR MASS ACROSS MUCH OF THE CONUS IS EXPECTED TO PRECLUDE ANY SEVERE THREAT THIS FORECAST PERIOD. A FEW REGIONS WILL... HOWEVER...HAVE SOME THUNDERSTORM ACTIVITY THIS AFTERNOON/EVENING AND/OR OVERNIGHT WITH THE GREATEST POTENTIAL ACROSS PARTS OF THE SOUTH CENTRAL STATES AND NRN ROCKIES. ...SW TX... A FEW THUNDERSTORMS HAVE ALREADY DEVELOPED OVER THE HIGHER TERRAIN OF SW TX /25 NE MRF/...WITH VISIBLE IMAGERY INDICATING ADDITIONAL CU/TCU DEVELOPING ALONG THE MOUNTAINS OF SW TX. STEEP LAPSE RATES AND SOME LARGE SCALE ASCENT WITH WEAK SHORT WAVE TROUGH...CURRENTLY MOVING SEWD ACROSS CENTRAL/SW TX...SHOULD ALLOW FOR A FEW ADDITIONAL DIURNAL STORMS ALONG THE HIGHER TERRAIN INTO THE EARLY EVENING. WEAK INSTABILITY WILL PRECLUDE A SEVERE WEATHER THREAT...THOUGH LARGE SURFACE DEWPOINT DEPRESSIONS MAY ALLOW FOR ISOLATED NON-SEVERE WIND GUSTS WITH ANY OF THE THUNDERSTORMS. ...NERN WA/FAR NRN ID INTO MT... SATELLITE IMAGERY/LIGHTNING DATA INDICATED THUNDERSTORMS HAD ALREADY DEVELOPED MAINLY ACROSS SERN BC. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE INTO THE EVENING SEWD ACROSS CENTRAL/ERN MT AS A SHORT WAVE TROUGH TRACKS EWD OVER THE NRN ROCKIES/SWRN CANADA. DESPITE MEAGER LOW-LEVEL MOISTURE...SURFACE HEATING AND STEEP LAPSE RATES WILL AID IN THE DEVELOPMENT OF HIGH BASED THUNDERSTORMS. ...ERN OK TO LOWER MS VALLEY... SLY LOW LEVEL FLOW DEVELOPING THIS FORECAST PERIOD ACROSS TX WILL ALLOW MOISTURE TO BEGIN RETURNING NWD...ESPECIALLY LATER TONIGHT. WAA...STEEP LAPSE RATES AND SOME LARGE SCALE ASCENT SPREADING SEWD ACROSS THIS REGION IN ASSOCIATION WITH A WEAK SHORT WAVE TROUGH EMBEDDED WITHIN NWLY FLOW ALOFT SHOULD ALLOW FOR ELEVATED TSTMS LATER THIS EVENING/OVERNIGHT ACROSS ERN OK INTO AR/NRN MS. ..PETERS.. 05/12/2006  From swody1 at goshenarc.org Sat May 13 05:15:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 01:15:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130513 SWODY1 SPC AC 130511 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1211 AM CDT SAT MAY 13 2006 VALID 131200Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CNTRL AND SRN AL THROUGH CNTRL AND SRN GA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN TX THROUGH THE LOWER MS VALLEY... ...SYNOPSIS... STAGNANT UPPER PATTERN WILL PERSIST THROUGH SATURDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND SHORTWAVE RIDGING OVER THE ROCKIES. SERIES OF VORTICITY MAXIMA WILL CONTINUE TO ROTATE THROUGH THE UPPER LOW. ONE SUCH FEATURE WILL MOVE SEWD INTO THE SERN STATES DURING THE DAY. A COLD FRONT WILL MOVE PROGRESSIVELY SWD AND BY LATE AFTERNOON SHOULD EXTEND FROM A SURFACE LOW OVER THE OH VALLEY SWWD INTO THE TN VALLEY...THEN WNWWD INTO SRN KS. ...CNTRL AL THROUGH CNTRL AND SRN GA... LOW LEVEL MOISTURE WILL REMAIN SOMEWHAT LIMITED THROUGH SATURDAY OVER THE SERN STATES...AND THIS WILL LIKELY SERVE AS AN OVERALL LIMITING FACTOR FOR A MORE ROBUST SEVERE WEATHER THREAT. CURRENT OBSERVATIONS SHOW SURFACE DEWPOINTS GENERALLY IN THE UPPER 40S TO LOWER 50S AND MUCH OF THIS MOISTURE IS CONFINED TO NEAR THE SURFACE. RICHER LOW LEVEL MOISTURE IS WELL SW OF THIS AREA IN SRN TX. WITH LITTLE IN THE WAY OF SIGNIFICANT MOISTURE ADVECTION...BOUNDARY LAYER MIXING SHOULD RESULT IN DEWPOINTS REMAINING IN THE UPPER 40S TO NEAR 50 DURING THE DAY. DESPITE THE LIMITED LOW LEVEL MOISTURE...STEEP LAPSE RATES AND SURFACE HEATING WILL RESULT IN SOME DESTABILIZATION WITH MLCAPE AOB 500 J/KG. A FEW ELEVATED STORMS MAY BE ONGOING WITHIN ZONE OF WARM ADVECTION AND ASCENT ASSOCIATED WITH A WLY LOW LEVEL JET AND SEWD ADVANCING SHORTWAVE TROUGH. POTENTIAL WILL EXIST FOR SOME OF THIS ACTIVITY TO INTENSIFY AND BECOME SURFACE BASED AS THE DOWNSTREAM ATMOSPHERE DESTABILIZES. THERMODYNAMIC PROFILES WILL LIKELY BE CHARACTERIZED BY INVERTED-V BOUNDARY LAYERS WITH UPDRAFTS HAVING RELATIVELY HIGH BASES. PRIMARY THREAT WILL BE ISOLATED DAMAGING WIND AND MARGINALLY SEVERE HAIL AS ACTIVITY SPREADS ESEWD. THREAT SHOULD DIMINISH BY EARLY EVENING. ...NERN TX...EXTREME SERN OK THROUGH THE LOWER MS VALLEY... PARTIALLY MODIFIED GULF AIR WITH DEWPOINTS IN THE LOWER 60S SHOULD BEGIN RETURNING NWD THROUGH TX BENEATH STEEP MID LEVEL LAPSE RATES BY SATURDAY NIGHT AS THE NOCTURNAL LOW LEVEL JET INCREASES. STORMS ARE EXPECTED TO DEVELOP WITHIN ZONE OF INCREASING WARM ADVECTION AND LIFT FROM NERN TX SPREADING EWD INTO THE LOWER MS VALLEY REGION. ACTIVITY WILL LIKELY BE ELEVATED...BUT THERMODYNAMIC PROFILES APPEAR SUFFICIENT FOR A THREAT FOR HAIL WITHIN THE STRONGER STORMS. ..DIAL/CROSBY.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 12:33:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 08:33:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131231 SWODY1 SPC AC 131229 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 AM CDT SAT MAY 13 2006 VALID 131300Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE GULF COAST REGION... ...AL/GA... MORNING WATER VAPOR IMAGERY SHOWS A LARGE UPPER LOW OVER THE EASTERN STATES...WITH SEVERAL WEAK DISTURBANCES ROTATING AROUND BASE OF LOW AND ACROSS THE MS VALLEY AND GULF COAST REGION. ONE SUCH FEATURE IS EVIDENT THIS MORNING OVER MO/AR. THIS TROUGH IS EXPECTED TO TRACK EAST-SOUTHEASTWARD ACROSS PARTS OF AL/MS/GA BY EVENING. AIR MASS AHEAD OF THIS FEATURE WILL BECOME MODERATELY UNSTABLE THIS AFTERNOON AS STRONG DAYTIME HEATING AND VERTICAL MIXING OCCUR. VERTICAL SHEAR WILL ALSO BE QUITE FAVORABLE FOR ORGANIZED/SUPERCELL STORMS. PRESENT INDICATIONS ARE THAT MORNING STORMS WILL PERSIST FOR SEVERAL MORE HOURS...EVENTUALLY TRACKING INTO WESTERN GA BEFORE WEAKENING. HAIL WILL REMAIN THE PRIMARY THREAT WITH THIS ISOLATED ACTIVITY THROUGH MIDDAY. MODELS GENERALLY AGREE ON THE REDEVELOPMENT OF STRONG/SEVERE STORMS OVER MIDDLE TN/NORTHERN AL NEAR/AFTER SUNSET AS NOCTURNAL LOW LEVEL JET STRENGTHENS. THESE STORMS WILL LIKELY BE CAPABLE OF LARGE NAIL AND DAMAGING WINDS FOR A FEW HOURS DURING THE EVENING. ...TX/LA/MS.... FARTHER WEST ACROSS PORTIONS OF MS AND THE ARKLATEX...CONVECTIVE INITIATION WILL BE LATER TONIGHT. STEEP LOW/MID LEVEL LAPSE RATES ARE LIKELY TO DEVELOP ALONG AND SOUTH OF SURFACE FRONT EXTENDING FROM NORTH TX INTO CENTRAL MS. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER DARK ALONG FRONT...SAGGING SLOWLY SOUTHWARD OVERNIGHT. A FEW SEVERE STORMS WILL BE POSSIBLE...CAPABLE OF HAIL AND DAMAGING WINDS. ..HART/CROSBIE.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 16:36:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 12:36:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131628 SWODY1 SPC AC 131627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT SAT MAY 13 2006 VALID 131630Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN TX EWD ACROSS LOWER MS VALLEY INTO GA... ...SYNOPSIS... AS UPPER LOW NOW OVER SRN WI DROPS SEWD INTO OH VALLEY STRONG WIND MAX CURRENTLY VICINITY MKC WILL MOVE ACROSS LOWER MO VALLEY INTO TN VALLEY BY THIS EVENING. COLD FRONT FROM SRN WI SURFACE LOW TRAILS SWWD ACROSS MO INTO NERN OK AND THEN WWD ACROSS TX PANHANDLE. FRONT WILL MOVE SLOWLY SWD EXTENDING FROM TN/AR BORDER WSWWD TO VICINITY NRN TX/OK BORDER BY THIS EVENING. STEEP MID LEVEL LAPSE RATES HAVE SPREAD EWD ACROSS SRN STATES AHEAD OF COLD FRONT WHICH ALONG WITH THE STRONG VEERING SHEAR PROFILES IS PROVIDING A SET UP FOR POTENTIALLY AN ACTIVE SEVERE THUNDERSTORM PERIOD. THE ONE CAVEAT WILL BE QUALITY OF LOW LEVEL MOISTURE WHICH IS RETURNING NEWD FROM WRN GULF ACROSS TX INTO LOWER MS VALLEY ATTM. ...GULF STATES... STRONG HEATING WILL PUSH SURFACE TEMPERATURES TO 80F OR ABOVE ACROSS MUCH OF GULF STATES THIS AFTERNOON. WITH LAPSE RATES IN EXCESS OF 7C/KM COUPLED WITH 40-50KT OF DEEP LAYER SHEAR THE INHIBITION WILL WEAKEN SUFFICIENTLY FOR THUNDERSTORMS TO DEVELOP BY MID AFTERNOON. THIS MORNINGS ELEVATED ACTIVITY SHOULD RESULT IN PROVIDING SURFACE BOUNDARIES TO FOCUS INITIATION THIS AFTERNOON FROM NRN MS INTO CENTRAL AL/GA. WITH STILL LIMITED LOW LEVEL MOISTURE...MLCAPES TO 1000 J/KG ARE ALL THAT ARE EXPECTED IN THIS REGION...WHICH WILL LIMIT THE INTENSITY OF STORMS. HOWEVER HAIL...SOME SEVERE...IS LIKELY WITH MANY OF THE STORMS CONSIDERING THE COOL...STEEP LAPSE RATES AND STRONG SHEAR. ADDITIONALLY STEEP LOW LEVEL LAPSE RATES WILL ENHANCE LOCAL DAMAGING WIND POTENTIAL. ...LOWER MS VALLEY INTO NRN TX... HAVE EXPANDED AND INCREASED THE THREAT OF SEVERE THUNDERSTORMS...PARTICULARLY OF LARGE HAIL...FOR LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS FROM NRN TX EWD TO MS. MODELS APPEAR TO BE HAVING CONSIDERABLE DIFFICULTY HANDLING THE ONGOING SHALLOW MOISTURE RETURN ACROSS TX. NAM AND EVEN THE 12Z GFS RUNS SEEMS TO EXCESSIVELY INCREASE BOUNDARY LAYER MOISTURE AHEAD OF COLD FRONT ACROSS NERN TX WITH FORECASTS OF NEAR 70F DEWPOINT LATE THIS AFTERNOON. OBSERVED MOISTURE SUGGEST POSSIBLE LOW/MID 60S CAN BE EXPECTED WHICH COUPLED WITH STRONG HEATING...INCREASINGLY FAVORABLE DEEP LAYER SHEAR AS WIND MAX ROTATES SEWD TOWARD WRN TN VALLEY...STILL SUPPORT SEVERE THUNDERSTORMS. WITH MLCAPES LIKELY BETWEEN 2000-2500 J/KG BY LATER THIS AFTERNOON AND LITTLE CIN AS TEMPERATURES HEAT THRU THE 80S...STORMS SHOULD INITIATE...MOST LIKELY BY EVENING ALONG/AHEAD OF COLD FRONT DROPPING SWD ACROSS SRN AR INTO NRN TX. SUPERCELLS WILL DEVELOP WHICH WILL ENHANCE POTENTIAL FOR VERY LARGE HAIL BY LATE AFTERNOON INTO OVERNIGHT HOURS ACROSS NRN TX EWD INTO MS. TORNADO POTENTIAL WILL BE LIMITED BY EXPECTED HIGH LCLS AND WEAKER SHEAR IN AREA OF BEST INSTABILITY ACROSS ERN TX AND WEAKER INSTABILITY FURTHER E WHERE THE SHEAR WILL BE STRONGER. POTENTIAL FOR SEVERE STORMS WILL CONTINUE WELL AFTER DARK AS ACTIVITY GRADUALLY SHIFTS S/SEWD ACROSS ERN TX AND LOWER MS VALLEY AS SHEAR WILL REMAIN QUITE FAVORABLE WITH PROXIMITY OF UPPER LOW AND WIND MAX TO THE N. WILL MONITOR THE MOISTURE FOR POSSIBLE UPGRADE FOR PORTIONS OF THE SLIGHT RISK IF INSTABILITY CAN INCREASE TO A GREATER DEGREE THAN NOW EXPECTED. ..HALES/GRAMS.. 05/13/2006  From swody1 at goshenarc.org Sat May 13 20:04:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 16:04:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 132000 SWODY1 SPC AC 131959 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0259 PM CDT SAT MAY 13 2006 VALID 132000Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN TX EWD ACROSS LOWER MS VALLEY INTO GA... ...GULF STATES... SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING FROM WRN TN SWWD INTO CENTRAL AR AND THEN WWD THROUGH CENTRAL OK TO THE TX PANHANDLE. AN OUTFLOW BOUNDARY FROM EARLIER CONVECTION ACROSS AL/GA EXTENDED FROM SWRN GA/SERN AL WNWWD ACROSS SRN TO WRN AL TO NRN MS. MOISTURE RETURN ACROSS THE GULF COAST STATES HAS BEEN SOMEWHAT LIMITED THUS FAR PRIMARILY TO THE SURFACE/NEAR SURFACE LAYER. HOWEVER...PRESENCE OF STEEP MID LEVEL LAPSE RATES IS CONTRIBUTING TO SBCAPE VALUES AROUND 1500 J/KG OVER SRN AL TO 2000 J/KG IN NRN MS WHERE SURFACE DEWPOINTS WERE HIGHER. INCREASING LARGE SCALE ASCENT SPREADING SEWD ACROSS TN VALLEY AND GULF COAST STATES THIS AFTERNOON/EVENING WITH THE APPROACH OF SRN MO/NRN AR SHORT WAVE TROUGH/MID LEVEL SPEED MAX EXPECTED TO AID IN THUNDERSTORM DEVELOPMENT. HAIL WILL BE LIKELY WITH MANY OF THE STORMS GIVEN STRONG DEEP LAYER SHEAR AND STEEP LAPSE RATES...WHILE INDICATION OF LOW RH VALUES/DRY AIR IN LOW LEVELS PER 1730Z ACARS DATA AT MEM SHOULD PROMOTE POTENTIAL FOR STRONG WIND GUSTS. ALTHOUGH ERN PARTS OF AL/CENTRAL GA ARE RATHER STABLE PER CLOUDINESS LEFT OVER FROM EARLIER CONVECTION...SLIGHT RISK WILL BE MAINTAINED ACROSS THIS REGION GIVEN POTENTIAL FOR UPSTREAM STORMS...ONCE THEY DEVELOP...TO TRACK INTO THIS AREA LATER THIS EVENING. ...LOWER MS VALLEY INTO NRN TX... NWD MOISTURE RETURN IS ONGOING FROM THE TX COAST TO CENTRAL/ERN PARTS OF THE RED RIVER VALLEY. SURFACE TEMPERATURES RISING THROUGH THE 80S BENEATH A PLUME OF STEEP LAPSE RATES WERE CONTRIBUTING TO INCREASING INSTABILITY AS EXPECTED PER EARLIER OUTLOOK. HOWEVER... THESE STEEP LAPSE RATES WERE ALSO RESULTING IN A STRONG CAP THAT IS EXPECTED TO PRECLUDE SURFACE BASED DEVELOPMENT ALONG THE SWD MOVING COLD FRONT UNTIL THIS EVENING ACROSS NRN TX INTO SRN AR. MOISTURE ADVECTION THROUGH THE FORECAST PERIOD SHOULD RESULT IN MLCAPE VALUES UP TO 2500 ACROSS ERN TX LATE THIS AFTERNOON. INSTABILITY EXPECTED TO REMAIN STRONG INTO THE OVERNIGHT PERIOD AS STRENGTHENING SSWLY LLJ AIDS IN NWD MOISTURE TRANSPORT AND INCREASING WAA. ONCE STORMS DEVELOP...STRONG DEEP LAYER SHEAR...PER PROXIMITY OF MID LEVEL WIND MAX EXTENDING FROM ERN KS TO TN VALLEY...AND STRONG INSTABILITY WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND DAMAGING WINDS. AS COLD FRONT MOVES SWD ACROSS ERN TX/LOWER MS VALLEY TONIGHT...SEVERE THREAT EXPECTED TO PERSIST WELL AFTER DARK GIVEN PROGGED MAGNITUDE OF ELEVATED INSTABILITY/BULK SHEAR. ...ERN PA INTO PARTS OF CENTRAL/WRN NY... AFTERNOON WATER VAPOR IMAGERY INDICATED SEVERAL VORTICITY MAXIMA ROTATING AROUND THE ERN PERIPHERY OF THE LARGE ERN STATES UPPER CYCLONE. ONE SUCH MID LEVEL IMPULSE WAS LOCATED OVER NERN PA/ CENTRAL NY AND AIDING WITH ONGOING THUNDERSTORMS ACROSS ERN PA NNWWD INTO CENTRAL/WRN NY. ADDITIONAL LARGE SCALE ASCENT IS EXPECTED TO SPREAD NWD ACROSS THIS SAME REGION LATER THIS AFTERNOON/EVENING AS A PAIR OF UPSTREAM IMPULSES LOCATED OVER SERN VA AND CENTRAL NC AT 18Z ROTATE NWD. WEAK LOW-LEVEL CONVERGENCE ALONG SURFACE TROUGH AND ASCENT WITH VORTICITY MAXIMA EXPECTED TO SUPPORT ADDITIONAL THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING. WEAK INSTABILITY /MLCAPE 500-800 J/KG/ AND MODEST DEEP LAYER SHEAR /20-25 KT/ SHOULD LIMIT STORM ORGANIZATION...THOUGH A FEW STORMS MAY BECOME STRONG ENOUGH TO PRODUCE MARGINALLY SEVERE HAIL AND/OR STRONG WIND GUSTS. ..PETERS.. 05/13/2006  From swody1 at goshenarc.org Sun May 14 01:06:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 13 May 2006 21:06:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140101 SWODY1 SPC AC 140100 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0800 PM CDT SAT MAY 13 2006 VALID 140100Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF NERN TX INTO EXTREME SERN OK...THE LOWER MS VALLEY AND PARTS OF THE SERN STATES... ...SRN PORTIONS OF TN VALLEY THROUGH PORTIONS OF THE SERN STATES... ZONE OF LARGE SCALE ASCENT ASSOCIATED WITH EXIT REGION OF A SEWD MOVING JET STREAK IS CONTRIBUTING TO THE DEVELOPMENT OF SCATTERED THUNDERSTORMS FROM CNTRL AND NRN AL THROUGH PART OF NRN GA AND SRN TN. INSTABILITY IS SOMEWHAT LIMITED WITH BOUNDARY LAYER DEWPOINTS GENERALLY IN THE 50S...BUT STEEP LAPSE RATES AND BOUNDARY LAYER WARMING HAVE RESULTED IN MLCAPE ON THE ORDER OF 500 TO 1000 J/KG. STRONG DEEP LAYER SHEAR OF 50+ KT ENHANCED BY THE UPPER JET AND CHARACTERIZED BY SSWLY LOW LEVEL FLOW VEERING TO NWLY AT 6 KM IS RESULTING IN A FAVORABLE KINEMATIC ENVIRONMENT FOR STORMS TO ROTATE. STEEP MID LEVEL LAPSE RATES AND COOL THERMODYNAMIC PROFILES AS WELL AS POTENTIAL FOR MID LEVEL UPDRAFT ROTATION ARE CONTRIBUTING TO A THREAT FOR LARGE HAIL WITHIN THE STRONGER STORMS. ISOLATED DAMAGING WIND IS ALSO POSSIBLE GIVEN THE RELATIVELY DRY BOUNDARY LAYERS. SEVERE THREAT IS EXPECTED TO PERSIST AT LEAST INTO THE MID EVENING AS THE ATMOSPHERE DESTABILIZES EWD INTO GA AND WRN PARTS OF THE CAROLINAS. ...NERN TX...EXTREME SERN OK THROUGH THE LOWER MS VALLEY... A SURFACE FRONT EXTENDS FROM CNTRL AR WWD INTO SRN OK. THIS BOUNDARY WILL LIKELY SHIFT SWD INTO NRN TX AND SRN AR OVERNIGHT AS AN UPPER LEVEL JET SHIFTS SEWD THROUGH THE TN VALLEY. THE ATMOSPHERE S OF THIS BOUNDARY HAS BECOME QUITE UNSTABLE WITH STEEP MID LEVEL LAPSE RATES AND COOL MID LEVEL TEMPERATURES ABOVE BOUNDARY LAYER DEWPOINTS IN THE 60S. THE 00Z FORT WORTH RAOB SHOWS 3000 J/KG OF MLCAPE AND 8.9 C/KM LAPSE RATES BETWEEN 700 AND 500 MB. HOWEVER...IT ALSO SHOWS A RATHER PRONOUNCED CAP. A SLY LOW LEVEL JET WILL INCREASE TONIGHT ACROSS TX AND IMPINGE ON THE SWD MOVING BOUNDARY. LIFT ASSOCIATED WITH WARM ADVECTION AND INCREASING FRONTOGENETIC FORCING IN THE VICINITY OF THE BOUNDARY SHOULD EVENTUALLY WEAKEN THE CAP AND CONTRIBUTE TO THUNDERSTORM INITIATION LATER THIS EVENING FROM NERN TX INTO THE LOWER MS VALLEY. GIVEN THE VERY STEEP MID LEVEL LAPSE RATES AND SUPERCELL WIND PROFILES...VERY LARGE HAIL COULD ACCOMPANY THE STRONGER STORMS. ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE. ..DIAL.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 06:01:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 02:01:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140557 SWODY1 SPC AC 140555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN NM THROUGH CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS VA THROUGH THE CNTRL AND ERN CAROLINAS...SRN GA AND THE FL PANHANDLE... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THROUGH SUNDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND UPPER RIDGING OVER THE ROCKIES. A STRONG MID LEVEL JET WILL CONTINUE TO ROTATE SEWD THROUGH THE BASE OF THE UPPER TROUGH INTO THE SERN U.S. AND CAROLINAS. AS THIS OCCURS THE COLD FRONT CURRENTLY FROM THE TN VALLEY WWD THROUGH NRN TX WILL CONTINUE TO PUSH SWD DURING THE DAY. ...SERN NM THROUGH CNTRL AND SRN TX... LOW LEVEL DEWPOINTS IN THE UPPER 60S TO NEAR 70 WILL PERSIST OVER S CNTRL THROUGH S TX IN THE PRE-FRONTAL WARM SECTOR BENEATH STEEP MID LEVEL LAPSE RATES. THIS WILL RESULT IN STRONG INSTABILITY BY SUNDAY AFTERNOON AS THE BOUNDARY LAYER WARMS WITH MLCAPE FROM 2500 TO 3000 J/KG. STORMS MAY BE ONGOING SUNDAY MORNING OVER PARTS OF CNTRL TX. ACTIVITY SHOULD REDEVELOP AND INTENSIFY DURING THE AFTERNOON WITHIN ZONE OF FRONTOGENETIC FORCING ALONG SWD ADVANCING FRONT. ENELY BOUNDARY LAYER FLOW VEERING TO NWLY AT 6 KM WILL RESULT IN FAVORABLE VERTICAL SHEAR FOR ORGANIZED STORMS INCLUDING SUPERCELLS. THERMODYNAMIC PROFILES APPEAR SUPPORTIVE OF VERY LARGE HAIL...ESPECIALLY WITH ANY DISCRETE SUPERCELL STRUCTURES. ISOLATED DAMAGING WIND MAY ALSO BE POSSIBLE...ESPECIALLY WITH ANY STORMS THAT MANAGE TO EVOLVE INTO LINES OR CLUSTERS. OTHER STORMS MAY DEVELOP OVER THE HIGHER TERRAIN OF SERN NM WHERE SURFACE HEATING AND EVOLVING UPSLOPE REGIME SHOULD SUPPORT INITIATION BY MID AFTERNOON. LOW LEVEL MOISTURE WILL BE MORE LIMITED IN THIS REGION WITH MLCAPE BELOW 1000 J/KG. SUPERCELLS WITH LARGE HAIL WILL BE THE PRIMARY THREAT. ...VA THROUGH THE CNTRL AND ERN CAROLINAS INTO SRN GA AND THE FL PANHANDLE... FORCING FOR ASCENT ASSOCIATED WITH EXIT REGION OF MID LEVEL JET WILL SPREAD EWD INTO THE CAROLINAS AND MID ATLANTIC DURING THE DAY. CONVECTION CURRENTLY MOVING EWD THROUGH THE CAROLINAS WILL LIKELY WEAKEN OWING TO LIMITED INSTABILITY. HOWEVER...SOME RESIDUAL CLOUDS AND THUNDERSTORMS MAY STILL BE IN PROGRESS EARLY SUNDAY MORNING. LOW LEVEL MOISTURE WILL REMAIN MORE LIMITED FROM THE CAROLINAS INTO VA. HOWEVER...COLD MID LEVEL TEMPERATURES WITH -18 TO -20 AT 500 MB WILL CONTRIBUTE TO STEEP MID LEVEL LAPSE RATES. WHERE SURFACE HEATING DEVELOPS...THE ATMOSPHERE WILL DESTABILIZE WITH MLCAPE FROM 500 TO 1000 J/KG. FARTHER S OVER S GA INTO THE FL PANHANDLE...RICHER LOW LEVEL MOISTURE WILL EXIST...BUT THIS WILL BE OFFSET SOMEWHAT BY WARMER MID LEVEL TEMPERATURES S OF UPPER JET. STORMS SHOULD REDEVELOP AND INTENSIFY BY EARLY AFTERNOON AS THE ATMOSPHERE DESTABILIZES WITHIN ZONE OF ASCENT ASSOCIATED WITH JET EXIT REGION FROM ERN GA THROUGH THE CAROLINAS INTO VA. STRONG VERTICAL SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING POTENTIAL FOR SUPERCELLS AS WELL AS LINES WITH DAMAGING WIND AND LARGE HAIL THE PRIMARY THREATS THROUGH EARLY EVENING. OTHER ACTIVITY MAY DEVELOP SWWD INTO SRN GA AND THE FL PANHANDLE ALONG SURFACE BOUNDARY AND WITHIN JET ENTRANCE REGION BY LATE AFTERNOON INTO THE EVENING. ..DIAL/CROSBY.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 06:01:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 02:01:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140557 SWODY1 SPC AC 140555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN NM THROUGH CNTRL AND SRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS VA THROUGH THE CNTRL AND ERN CAROLINAS...SRN GA AND THE FL PANHANDLE... ...SYNOPSIS... UPPER PATTERN WILL CHANGE LITTLE THROUGH SUNDAY WITH A LARGE UPPER LOW OVER THE ERN U.S. AND UPPER RIDGING OVER THE ROCKIES. A STRONG MID LEVEL JET WILL CONTINUE TO ROTATE SEWD THROUGH THE BASE OF THE UPPER TROUGH INTO THE SERN U.S. AND CAROLINAS. AS THIS OCCURS THE COLD FRONT CURRENTLY FROM THE TN VALLEY WWD THROUGH NRN TX WILL CONTINUE TO PUSH SWD DURING THE DAY. ...SERN NM THROUGH CNTRL AND SRN TX... LOW LEVEL DEWPOINTS IN THE UPPER 60S TO NEAR 70 WILL PERSIST OVER S CNTRL THROUGH S TX IN THE PRE-FRONTAL WARM SECTOR BENEATH STEEP MID LEVEL LAPSE RATES. THIS WILL RESULT IN STRONG INSTABILITY BY SUNDAY AFTERNOON AS THE BOUNDARY LAYER WARMS WITH MLCAPE FROM 2500 TO 3000 J/KG. STORMS MAY BE ONGOING SUNDAY MORNING OVER PARTS OF CNTRL TX. ACTIVITY SHOULD REDEVELOP AND INTENSIFY DURING THE AFTERNOON WITHIN ZONE OF FRONTOGENETIC FORCING ALONG SWD ADVANCING FRONT. ENELY BOUNDARY LAYER FLOW VEERING TO NWLY AT 6 KM WILL RESULT IN FAVORABLE VERTICAL SHEAR FOR ORGANIZED STORMS INCLUDING SUPERCELLS. THERMODYNAMIC PROFILES APPEAR SUPPORTIVE OF VERY LARGE HAIL...ESPECIALLY WITH ANY DISCRETE SUPERCELL STRUCTURES. ISOLATED DAMAGING WIND MAY ALSO BE POSSIBLE...ESPECIALLY WITH ANY STORMS THAT MANAGE TO EVOLVE INTO LINES OR CLUSTERS. OTHER STORMS MAY DEVELOP OVER THE HIGHER TERRAIN OF SERN NM WHERE SURFACE HEATING AND EVOLVING UPSLOPE REGIME SHOULD SUPPORT INITIATION BY MID AFTERNOON. LOW LEVEL MOISTURE WILL BE MORE LIMITED IN THIS REGION WITH MLCAPE BELOW 1000 J/KG. SUPERCELLS WITH LARGE HAIL WILL BE THE PRIMARY THREAT. ...VA THROUGH THE CNTRL AND ERN CAROLINAS INTO SRN GA AND THE FL PANHANDLE... FORCING FOR ASCENT ASSOCIATED WITH EXIT REGION OF MID LEVEL JET WILL SPREAD EWD INTO THE CAROLINAS AND MID ATLANTIC DURING THE DAY. CONVECTION CURRENTLY MOVING EWD THROUGH THE CAROLINAS WILL LIKELY WEAKEN OWING TO LIMITED INSTABILITY. HOWEVER...SOME RESIDUAL CLOUDS AND THUNDERSTORMS MAY STILL BE IN PROGRESS EARLY SUNDAY MORNING. LOW LEVEL MOISTURE WILL REMAIN MORE LIMITED FROM THE CAROLINAS INTO VA. HOWEVER...COLD MID LEVEL TEMPERATURES WITH -18 TO -20 AT 500 MB WILL CONTRIBUTE TO STEEP MID LEVEL LAPSE RATES. WHERE SURFACE HEATING DEVELOPS...THE ATMOSPHERE WILL DESTABILIZE WITH MLCAPE FROM 500 TO 1000 J/KG. FARTHER S OVER S GA INTO THE FL PANHANDLE...RICHER LOW LEVEL MOISTURE WILL EXIST...BUT THIS WILL BE OFFSET SOMEWHAT BY WARMER MID LEVEL TEMPERATURES S OF UPPER JET. STORMS SHOULD REDEVELOP AND INTENSIFY BY EARLY AFTERNOON AS THE ATMOSPHERE DESTABILIZES WITHIN ZONE OF ASCENT ASSOCIATED WITH JET EXIT REGION FROM ERN GA THROUGH THE CAROLINAS INTO VA. STRONG VERTICAL SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING POTENTIAL FOR SUPERCELLS AS WELL AS LINES WITH DAMAGING WIND AND LARGE HAIL THE PRIMARY THREATS THROUGH EARLY EVENING. OTHER ACTIVITY MAY DEVELOP SWWD INTO SRN GA AND THE FL PANHANDLE ALONG SURFACE BOUNDARY AND WITHIN JET ENTRANCE REGION BY LATE AFTERNOON INTO THE EVENING. ..DIAL/CROSBY.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 12:23:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 08:23:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141220 SWODY1 SPC AC 141219 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0719 AM CDT SUN MAY 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SOUTHERN PLAINS AND LOWER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC REGION INTO THE SOUTHEAST STATES... ...LA/TX... MORNING WATER VAPOR IMAGERY SHOWS LARGE UPPER LOW OVER THE EASTERN STATES...WITH BAND OF STRONG NORTHWEST FLOW ALOFT EXTENDING FROM THE CENTRAL PLAINS INTO THE CENTRAL GULF COAST REGION. CLUSTER OF SEVERE STORMS IS ONGOING THIS MORNING OVER EAST TX. THESE STORMS APPEAR TO BE IN RIGHT ENTRANCE REGION OF CYCLONIC UPPER JET MAX OVER THE MS VALLEY...AND WILL LIKELY CONTINUE THROUGH THE MORNING HOURS. PRESENT INDICATIONS ARE THAT ACTIVITY WILL SPREAD SOUTHWARD TOWARD THE UPPER TX GULF COAST BY MIDDAY WITH THE POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS. OTHER STORMS ARE LIKELY TO DEVELOP WESTWARD FROM THIS ACTIVITY BY MID/LATE AFTERNOON ACROSS CENTRAL TX. HIGH CAPE VALUES EXCEEDING 4000 J/KG AND BACKED LOW LEVEL WINDS WILL ENHANCE THE RISK OF SUPERCELLS CAPABLE OF VERY LARGE HAIL. THESE STORMS MAY DEVELOP INTO SOUTH TX TONIGHT BEFORE WEAKENING. FINALLY...ISOLATED SEVERE STORMS WILL BE POSSIBLE OVER SOUTHEAST NM AND WEST TX IN LOW LEVEL UPSLOPE FLOW REGIME. PRESENT INDICATIONS ARE THAT WEAK INSTABILITY WILL LIMIT AREAL COVERAGE OF SEVERE STORMS IN THAT REGION. ...MID ATLANTIC INTO SOUTHEAST STATES... MID/UPPER LEVEL SPEED MAX WILL ROTATE FROM THE MS/TN VALLEY INTO THE MID ATLANTIC REGION BY THIS AFTERNOON. THIS WILL RESULT IN INCREASING FORCING FOR UPWARD VERTICAL MOTION FROM CENTRAL VA ACROSS THE CAROLINAS BY EARLY AFTERNOON. LOW LEVEL MOISTURE VALUES ARE ONLY MARGINAL WITH SURFACE DEWPOINTS GENERALLY IN THE LOW/MID 50S. HOWEVER...COLD TEMPERATURES ALOFT /500MB TEMPERATURES OF -18 TO -20C/ AND STEEP LAPSE RATES WILL PROMOTE RAPID DESTABILIZATION WITH A FEW HOURS OF HEATING...AND THE RISK OF HAIL IN STRONGER CELLS. VERTICAL SHEAR PROFILES WILL ALSO BE FAVORABLE FOR SUPERCELLS AND ISOLATED TORNADOES. ACTIVITY IS EXPECTED TO SPREAD OFF THE VA/CAROLINA COAST BY EARLY EVENING...ENDING THE THREAT OF SEVERE STORMS. ISOLATED STRONG/SEVERE STORMS MAY ALSO EXTEND SOUTHWESTWARD FROM PRIMARY ACTIVITY...INTO PARTS OF GA/AL/FL THIS AFTERNOON IN MOIST/UNSTABLE AIR MASS. ..HART.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 16:27:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 12:27:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141612 SWODY1 SPC AC 141610 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1110 AM CDT SUN MAY 14 2006 VALID 141630Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS THE GULF STATES TO THE MID ATLANTIC COAST... ...SYNOPSIS... LARGE UPPER COLD LOW MOVES SLOWLY EWD ACROSS OH VALLEY THRU TONIGHT AS A STRONG MID LEVEL WIND MAX NOW ACROSS TN VALLEY CONTINUES ROTATING EWD TO ACROSS CAROLINAS BY THIS EVENING. SLOWLY DEVELOPING SURFACE LOW FAR WRN VA WILL MOVE EWD VICINITY VA/NC BORDER THIS AFTERNOON IN CONCERT WITH THE PRONOUNCED EXIT REGION OF THE STRONG MID LEVEL JET. COLD FRONT TRAILS WSWWD ACROSS NRN GA TO SRN AR AND THEN INTO FAR SWRN TX. ...MID ATLANTIC REGION... STEEP MID LEVEL LAPSE RATES HAVE SPREAD EWD ACROSS THE MID ATLANTIC STATES AHEAD OF APPROACHING UPPER LEVEL LOW AND WIND MAX. AS THE SURFACE LOW WRN VA MOVES EWD...LOW LEVEL WINDS ACROSS SERN VA INTO NERN NC WILL BACK AND GRADUALLY INCREASE THRU THE AFTERNOON...PROVIDING A FAVORABLE SUPERCELL ENVIRONMENT. LOW LEVEL MOISTURE SUFFICIENT GIVEN COOL...STEEP LAPSE RATES FOR MLCAPES RISING TO 1000 J/KG WHERE SURFACE TEMPERATURES CAN HEAT INTO THE LOW/MID 70S. WHILE HAIL WILL BE PRIMARY THREAT AS STORMS DEVELOP BY EARLY THIS AFTERNOON GIVEN THE FAVORABLE FREEZING LEVELS...THERE WILL BE SUFFICIENT SPEED AND DIRECTIONAL SHEAR FOR SUPERCELL FORMATION. MOST FAVORABLE SUPERCELL AREA ALONG WITH ISOLATED TORNADO POTENTIAL WILL BE IN ADVANCE OF SURFACE LOW UNDER APPROACHING STRONG MID LEVEL JET. STORMS ALSO COULD EVOLVE INTO SHORT LINES/BOWS UNDER THE STRONG UPPER JET FOR A MORE ORGANIZED WIND THREAT. ...TX TO LOWER MS VALLEY... A MUCH MORE UNSTABLE AIR MASS IS IN PLACE ACROSS CENTRAL/SRN TX TO S OF FRONTAL ZONE. ONGOING STRONG/SEVERE THUNDERSTORMS EXPECTED WITH AFTERNOON HEATING TO INCREASE IN NUMBER AND INTENSITY AS THE STORMS CONTINUE DEVELOPING S/SEWD THRU MUCH OF TX BY LATER TONIGHT. GIVEN MLCAPES RISING TO ABOVE 3000 J/KG AND 40-45 KT OF DEEP LAYER SHEAR...VERY LARGE HAIL WILL BE THE DOMINANT THREAT. THERMODYNAMIC PARAMETERS GIVEN THE DEEP LAYER SHEAR ALSO SUPPORT SUPERCELL POTENTIAL. LARGEST HAIL ALONG WITH ISOLATED TORNADOES WOULD BE ASSOCIATED WITH ANY SUPERCELL THAT DEVELOPS. SEVERE STORMS WILL PROPAGATE INTO THE VERY UNSTABLE AIR MASS ACROSS S TX AND LIKELY CONTINUE AFTER DARK. FURTHER E ALONG GULF COAST...WHILE LAPSE RATES FAVOR A FEW SEVERE STORMS...INSTABILITY AND SHEAR WILL BE A LITTLE LESS THAN THE AFOREMENTION AREAS. SEVERE POTENTIAL THUS WOULD BE MORE WIDELY SCATTERED WITH LARGE HAIL THE DOMINANT THREAT. ...SRN HIGH PLAINS... UPSLOPE FLOW HAS SPREAD WWD INTO ERN NM AND W OF PECOS VALLEY IN FAR SWRN TX ALONG WITH LOW LEVEL MOISTURE. VERY STEEP LAPSE RATES ABOVE SHALLOW SURFACE MOISTURE PERSIST THIS REGION. STRONG HEATING COUPLED WITH 40-50 KT OF DEEP LAYER SHEAR WILL BE ADEQUATE FOR A FEW SEVERE THUNDERSTORMS TO DEVELOP OVER HIGHER TERRAIN ERN NM/SWRN TX. IN THE NWLY FLOW...STORMS WOULD THEN DEVELOP S/SEWD THRU THE HIGH PLAINS DURING EVENING WITH LARGE HAIL AND LOCAL DOWNBURSTS THE PRIMARY CONCERN. ..HALES/GRAM.. 05/14/2006  From swody1 at goshenarc.org Sun May 14 20:09:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 16:09:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 142006 SWODY1 SPC AC 142004 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0304 PM CDT SUN MAY 14 2006 VALID 142000Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN HIGH PLAINS EWD ACROSS THE GULF COAST STATES TO THE MID ATLANTIC REGION... ...MID ATLANTIC REGION... SC/NC/VA WILL REMAIN WITHIN EXIT REGION OF STRONG /70-80 KT/ MID LEVEL JET ROUNDING BASE OF LARGE UPPER CYCLONE NOW CENTERED OVER THE LOWER OH VALLEY. THIS WILL MAINTAIN FORCING FOR UPWARD VERTICAL MOTION AND ASSOCIATED SURFACE PRESSURE FALLS ACROSS THIS REGION FOR ADDITIONAL THUNDERSTORMS THROUGH THE REMAINDER OF THE AFTERNOON INTO THIS EVENING. STRONG FORCING AND KINEMATICS ASSOCIATED WITH SHORT WAVE TROUGH ROTATING NEWD ACROSS CAROLINAS/ MID ATLANTIC REGION WILL SUPPORT CONTINUED POTENTIAL FOR SUPERCELLS WITH HAIL/DAMAGING WINDS. BACKED LOW-LEVEL WINDS VICINITY DIFFERENTIAL HEATING BOUNDARY IN NRN/NERN NC AND SERN VA WILL BE MAINTAINED GIVEN AREA OF PRESSURE FALLS LOCATED EAST OF WRN NC SURFACE LOW AND SUPPORT GREATEST THREAT FOR TORNADOES. THIS TORNADO THREAT WILL CONTINUE INTO THE EVENING ALONG TRACK OF SURFACE LOW THROUGH MUCH OF NC AND POTENTIALLY SRN VA. ...TX TO GULF COAST STATES... SEVERE STORMS TO CONTINUE ACROSS CENTRAL/SE TX THIS AFTERNOON/ EVENING WITHIN CLUSTER OF STORMS ACROSS THIS REGION. VERY UNSTABLE AIR MASS /MLCAPE UP TO 3000 J/KG/ LOCATED OVER CENTRAL/SRN TX WILL SUPPORT ADDITIONAL SEVERE THUNDERSTORM DEVELOPMENT AS ADDITIONAL SURFACE HEATING WEAKENS INHIBITION AHEAD OF SWD MOVING COLD FRONT/OUTFLOW BOUNDARIES. NEW STORMS SHOULD CONTINUE TO DEVELOP WWD AS WELL INTO SW TX AS HEATING WEAKENS CINH FOR SURFACE BASED STORMS. STRONG DEEP LAYER SHEAR WILL CONTINUE TO SUPPORT SUPERCELLS WITH VERY LARGE HAIL LIKELY GIVEN THE MAGNITUDE OF AVAILABLE INSTABILITY/ STEEP LAPSE RATES. VERY UNSTABLE AIR MASS OVER DEEP S TX IS EXPECTED TO SUPPORT SEVERE POTENTIAL WELL AFTER DARK AS ONGOING ACTIVITY MOVES SWD LATER IN PERIOD. FARTHER E ACROSS LA TO CENTRAL GULF COAST STATES...AIR MASS ACROSS MUCH OF LA HAS BEEN STABILIZED BY EARLIER MCS...BUT AREAS OF SURFACE HEATING EWD ALONG GULF COAST REGION INTO SRN GA/NW FL EXPECTED TO MAINTAIN MODERATELY UNSTABLE AIR MASS. SURFACE FRONT EXTENDED FROM CENTRAL GA SWWD THROUGH SRN AL/MS WITH A WEAK SURFACE TROUGH EXTENDING FROM SRN GA TO THE ERN FL PANHANDLE. STRONG DEEP LAYER SHEAR ACROSS THIS AREA WILL PROMOTE THREAT FOR ORGANIZED STORMS THAT DEVELOP ALONG/S OF SWD MOVING SURFACE BOUNDARIES...WITH HAIL/ DAMAGING WIND GUSTS THE PRIMARY THREATS. ...SRN HIGH PLAINS... DESPITE RATHER DRY SUB-CLOUD LAYER/LOW SURFACE DEWPOINTS ACROSS CENTRAL ROCKIES INTO NRN NM...FORCING FOR LARGE SCALE ASCENT ASSOCIATED WITH SHORT WAVE TROUGH MOVING ESE OVER FOUR CORNERS REGION AND STEEP LAPSE RATES/SURFACE HEATING PROMOTING TSTMS. STRONG DEEP LAYER SHEAR ACROSS NRN NM MAY SUPPORT A SEVERE THREAT INTO THE EVENING...BUT WEAK INSTABILITY SHOULD LIMIT THE COVERAGE. GREATER SEVERE THREAT IS EXPECTED FARTHER S ACROSS SERN NM/SW TX LATER THIS AFTERNOON/EVENING AS WWD TRANSPORT OF LOW-LEVEL MOISTURE CONTINUES WITH ADDITIONAL SURFACE HEATING FURTHER DESTABILIZING THE AIR MASS WITH MLCAPES 1000-2000 J/KG. STRONG DEEP LAYER SHEAR ACROSS THIS REGION WILL SUPPORT SUPERCELLS WITH LARGE HAIL/DAMAGING WINDS THE PRIMARY THREATS. ..PETERS.. 05/14/2006  From swody1 at goshenarc.org Mon May 15 01:01:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 14 May 2006 21:01:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150058 SWODY1 SPC AC 150056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT SUN MAY 14 2006 VALID 150100Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM ERN VA/SRN CHESAPEAKE BAY SWD TO SRN GA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF CNTRL AND ERN NM SEWD TO S TX... ...ERN VA TO SRN GA... LATEST MESOANALYSIS INDICATED SURFACE LOW OVER CNTRL NC WHICH IS FORECAST TO DEVELOP NWD ALONG BAROCLINIC ZONE TOWARD THE DELMARVA OVERNIGHT. TRAILING COLD FRONT EXTENDING SWWD FROM THIS SURFACE LOW TO THE CNTRL GULF COAST WILL CONTINUE TO PUSH SEWD THROUGH MUCH OF THE SERN U.S. EXCEPT FL. REGIONAL VWPS AND 15/00Z SOUNDINGS INDICATE RELATIVELY STRONG LOW AND DEEP-LAYER SHEAR ACROSS THE PIEDMONT AND COASTAL PLAIN THIS EVENING OWING TO COUPLING OF WSWLY 60-70 KT MID-LEVEL JET STREAK AND 30-40 KT SWLY LLJ. SEVERAL CLUSTERS OF STRONG TO SEVERE STORMS /SOME OF WHICH EXHIBITING SUPERCELL STRUCTURES/ ARE ONGOING FROM VICINITY OF THE SURFACE LOW OVER CNTRL/ERN NC SWD INTO ERN SC AND SRN GA. OBSERVATIONAL DATA INDICATE THAT AIR MASS IS ONLY WEAKLY UNSTABLE WITH MLCAPES OF 500-800 J/KG...HOWEVER THE STRONG VERTICAL SHEAR SHOULD MAINTAIN THE THREAT OF LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES FOR THE NEXT SEVERAL HOURS. ...S TX... SURFACE AND SOUNDING DATA INDICATE THE PRESENCE OF A MOIST...HOT AND STRONGLY UNSTABLE / MLCAPES OF 2000-3000 J/KG / AIR MASS IN PLACE AHEAD OF MCS PROPAGATING SWD THROUGH THE REGION. PRESENCE OF STRONG DIRECTIONAL SHEAR AND RESULTANT 40-50 KTS OF EFFECTIVE SHEAR SHOULD SUPPORT EMBEDDED SUPERCELL STRUCTURES CAPABLE OF LARGE...DAMAGING HAIL AND PERHAPS A COUPLE BRIEF TORNADOES. OTHERWISE...STEEP LOW LEVEL LAPSE RATES AND DCAPES AOA 1500 J/KG SHOULD SUPPORT FURTHER ORGANIZATION OF MCS COLD POOL WITH A CONTINUING THREAT OF DAMAGING WINDS. ...ERN NM INTO FAR WRN AND SWRN TX... TSTMS HAVE DEVELOPED LATE THIS AFTERNOON AND EVENING OVER PARTS OF CNTRL INTO S-CNTRL NM AHEAD OF WEAK IMPULSE MOVING THROUGH ERN AZ. 15/00Z ELP SOUNDING INDICATES THAT THIS ACTIVITY IS DEVELOPING WITHIN A DEEPLY MIXED BOUNDARY-LAYER WITH MLCAPES OF 300-500 J/KG. THE PRESENCE OF STEEP LOW AND MID-LEVEL LAPSE RATES COUPLED WITH MODESTLY STRONG DEEP-LAYER VERTICAL SHEAR /35-45 KTS/ SHOULD SUPPORT A FEW ORGANIZED STORMS CAPABLE OF SOME SEVERE HAIL AND MORE SO LOCALLY DAMAGING WINDS. ONGOING STORMS OVER S-CNTRL NM MAY ATTEMPT TO ORGANIZE A COLD POOL TONIGHT...WITH A THREAT OF DAMAGING WINDS SPREADING SWD INTO FAR WRN TX. OTHER MORE ISOLATED STORMS CAPABLE OF LOCALLY HIGH WINDS AND HAIL WILL BE POSSIBLE ALONG THE HIGHER TERRAIN OF SWRN TX. ..MEAD.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 05:18:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 01:18:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150515 SWODY1 SPC AC 150513 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1213 AM CDT MON MAY 15 2006 VALID 151200Z - 161200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... AMPLIFIED LONG WAVE PATTERN WILL PERSIST THROUGH THE DAY ONE PERIOD...CHARACTERIZED BY TROUGHING IN THE E AND RIDGING IN THE W. MORE SPECIFICALLY...UPPER LOW NOW OVER THE MIDDLE OH VALLEY IS FORECAST TO SHIFT NEWD TOWARD THE MIDDLE ATLANTIC COAST AS VORTICITY MAXIMUM NOW OVER THE MID MS VALLEY ROTATES THROUGH MEAN TROUGH BASE AND THEN NEWD ALONG THE ATLANTIC COAST. MEANWHILE...ANOTHER VORTICITY MAXIMUM OVER THE WRN GREAT LAKES WILL PIVOT SWWD AND THEN SWD INTO THE LOWER MS VALLEY BY TUESDAY MORNING. IN THE W...SHORT WAVE TROUGH NOW OFF THE CNTRL CA COAST WILL LIFT NEWD ALONG THE PACIFIC NW COAST LATER TODAY INTO TONIGHT. IN THE LOW-LEVELS...PRIMARY SURFACE FRONT WILL EXTEND FROM LOW PRESSURE OVER THE DELMARVA SWD ALONG THE CNTRL/SRN ATLANTIC COASTAL PLAIN AND THEN MORE SWWD ACROSS NRN FL. THIS FRONT MAY REMAIN QUASI-STATIONARY OR WILL ONLY SLOWLY SHIFT EWD AND SEWD THROUGH THE DAY...PRIOR TO ACCELERATING TONIGHT WITH THE PASSAGE OF AFOREMENTIONED VORTICITY MAXIMUM AROUND UPPER LOW. ...SRN GA/FL... CONVERGENCE ALONG FRONT COUPLED WITH INCREASED FORCING FOR ASCENT AHEAD OF APPROACHING VORTICITY MAXIMUM ARE EXPECTED TO CONTRIBUTE TO AN INCREASE IN STORM COVERAGE AND INTENSITY BY AFTERNOON ACROSS NRN FL AND SRN GA. RELATIVELY WEAK MID-LEVEL LAPSE RATES SHOULD TEND TO LIMIT DESTABILIZATION PROCESS WITH MLCAPES OF 500-1000 J/KG. HOWEVER...RATHER STRONG VERTICAL SPEED SHEAR MAY SUPPORT A FEW ORGANIZED STORMS CAPABLE OF LOCALLY STRONG WIND GUSTS AND SOME SEVERE HAIL. THIS ISOLATED SEVERE THREAT IS EXPECTED TO DEVELOP SWD ALONG ERN FL SEA BREEZE BOUNDARY THIS AFTERNOON AS LOW-LEVEL CONVERGENCE IS ENHANCED BY THE AMBIENT WSWLY LOW-LEVEL FLOW. IN ADDITION TO ISOLATED HIGH WINDS/HAIL...A BRIEF TORNADO OR TWO WILL BE POSSIBLE WITH THE MORE INTENSE STORMS. ...ERN AZ/WRN NM... OROGRAPHIC FORCING COUPLED WITH LOW-LEVEL MASS CONVERGENCE ALONG WRN EXTENSION OF LOW-LEVEL BAROCLINIC ZONE ARE EXPECTED TO PROVIDE A FOCUS FOR DIURNAL TSTM DEVELOPMENT THIS AFTERNOON INTO EVENING. THE COMBINATION OF RELATIVELY STEEP LOW AND MID-LEVEL LAPSE RATES...STRONG LOW-LEVEL HODOGRAPH CURVATURE AND MODEST DEEP-LAYER SHEAR SHOULD SUPPORT A FEW ORGANIZED STORMS CAPABLE OF LOCALLY STRONG DOWNDRAFTS AND MARGINALLY SEVERE HAIL. ...PACIFIC NW... ISOLATED TO SCATTERED TSTM DEVELOPMENT WILL BE POSSIBLE ALONG THE CASCADES THIS AFTERNOON INTO TONIGHT IN ASSOCIATION WITH IMPULSE SHIFTING NNEWD ALONG THE PACIFIC COAST. HOWEVER...NAM BOUNDARY-LAYER MOISTURE FORECASTS ARE TOO HIGH WHICH IS RESULTING IN EXCESSIVE INSTABILITY. NO SEVERE WEATHER IS FORECAST. ..MEAD/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 12:51:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 08:51:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151248 SWODY1 SPC AC 151245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT MON MAY 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE EASTERN FL PENINSULA... ...EASTERN FL PENINSULA... PERSISTENT UPPER LOW OVER THE EASTERN STATES WILL REMAIN IN PLACE THROUGH TODAY...WITH MAIN SURFACE BAROCLINIC ZONE STRETCHING ACROSS SOUTHERN GA/NORTH FL AND ALONG THE CAROLINA COAST. AIR MASS ALONG AND SOUTH OF FRONT WILL BE MOIST AND MODERATELY UNSTABLE WITH AFTERNOON MLCAPE VALUES OVER 1500 J/KG. DEEP WESTERLY FLOW ACROSS THE FL PENINSULA SHOULD LIMIT INLAND PROGRESS OF EAST COAST SEA BREEZE...PROVIDING A FOCUS FOR AFTERNOON THUNDERSTORM DEVELOPMENT ALONG THE IMMEDIATE COAST. FAVORABLE DEEP LAYER VERTICAL SHEAR WILL BE PRESENT FOR UPDRAFT ROTATION AND THE POSSIBILITY OF HAIL/DAMAGING WINDS IN STRONGER CELLS. AN ISOLATED TORNADO ALSO CANNOT BE RULED OUT DUE TO BOUNDARY INTERACTIONS. ACTIVITY SHOULD DIMINISH IN INTENSITY SHORTLY AFTER 00Z. ...AZ/NM... WESTERN PERIPHERY OF NORTHERN MID LEVEL WINDS EXTENDS ALONG THE ROCKIES INTO EASTERN AZ/WESTERN NM. SUFFICIENT LOW/MID LEVEL MOISTURE AND STEEP LAPSE RATES WILL LIKELY BE PRESENT IN THIS REGION FOR SCATTERED AFTERNOON/EVENING THUNDERSTORMS. DESPITE WEAK VERTICAL SHEAR...ISOLATED STRONG CELLS CAPABLE OF GUSTY WINDS AND HAIL ARE POSSIBLE. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED IN THIS REGION TODAY. ...EASTERN NC... MORNING CLOUDINESS OVER EASTERN NC WILL LIKELY ERODE THIS AFTERNOON...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE AHEAD OF SURFACE COLD FRONT. SCATTERED THUNDERSTORMS MAY DEVELOP AFTER 18Z OVER EASTERN NC...MOVING OFFSHORE BEFORE 00Z. THIS REGION WILL BE BENEATH 70 KNOT MID LEVEL JET MAX...WITH MORE THAN SUFFICIENT VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS. AREAL COVERAGE MAY BE LIMITED...BUT GUSTY WINDS AND HAIL ARE POSSIBLE FROM ANY SUSTAINED STORM IN THIS REGION TODAY. ..HART/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 12:51:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 08:51:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151248 SWODY1 SPC AC 151245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT MON MAY 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE EASTERN FL PENINSULA... ...EASTERN FL PENINSULA... PERSISTENT UPPER LOW OVER THE EASTERN STATES WILL REMAIN IN PLACE THROUGH TODAY...WITH MAIN SURFACE BAROCLINIC ZONE STRETCHING ACROSS SOUTHERN GA/NORTH FL AND ALONG THE CAROLINA COAST. AIR MASS ALONG AND SOUTH OF FRONT WILL BE MOIST AND MODERATELY UNSTABLE WITH AFTERNOON MLCAPE VALUES OVER 1500 J/KG. DEEP WESTERLY FLOW ACROSS THE FL PENINSULA SHOULD LIMIT INLAND PROGRESS OF EAST COAST SEA BREEZE...PROVIDING A FOCUS FOR AFTERNOON THUNDERSTORM DEVELOPMENT ALONG THE IMMEDIATE COAST. FAVORABLE DEEP LAYER VERTICAL SHEAR WILL BE PRESENT FOR UPDRAFT ROTATION AND THE POSSIBILITY OF HAIL/DAMAGING WINDS IN STRONGER CELLS. AN ISOLATED TORNADO ALSO CANNOT BE RULED OUT DUE TO BOUNDARY INTERACTIONS. ACTIVITY SHOULD DIMINISH IN INTENSITY SHORTLY AFTER 00Z. ...AZ/NM... WESTERN PERIPHERY OF NORTHERN MID LEVEL WINDS EXTENDS ALONG THE ROCKIES INTO EASTERN AZ/WESTERN NM. SUFFICIENT LOW/MID LEVEL MOISTURE AND STEEP LAPSE RATES WILL LIKELY BE PRESENT IN THIS REGION FOR SCATTERED AFTERNOON/EVENING THUNDERSTORMS. DESPITE WEAK VERTICAL SHEAR...ISOLATED STRONG CELLS CAPABLE OF GUSTY WINDS AND HAIL ARE POSSIBLE. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED IN THIS REGION TODAY. ...EASTERN NC... MORNING CLOUDINESS OVER EASTERN NC WILL LIKELY ERODE THIS AFTERNOON...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE AHEAD OF SURFACE COLD FRONT. SCATTERED THUNDERSTORMS MAY DEVELOP AFTER 18Z OVER EASTERN NC...MOVING OFFSHORE BEFORE 00Z. THIS REGION WILL BE BENEATH 70 KNOT MID LEVEL JET MAX...WITH MORE THAN SUFFICIENT VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS. AREAL COVERAGE MAY BE LIMITED...BUT GUSTY WINDS AND HAIL ARE POSSIBLE FROM ANY SUSTAINED STORM IN THIS REGION TODAY. ..HART/CROSBIE.. 05/15/2006  From swody1 at goshenarc.org Mon May 15 16:33:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 12:33:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151630 SWODY1 SPC AC 151628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT MON MAY 15 2006 VALID 151630Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF FL PENINSULA... ...THERE IS A SLGT RISK OF SVR TSTMS EASTERN NORTH CAROLINA... ...FL/SERN GA... WITH UPPER LOW SLOWLY MOVING EWD THRU OH VALLEY...MDT/STG WESTERLIES REMAIN SERN U.S. FRONTAL ZONE EXTENDS FROM ERN NC SWWD THRU SRN GA TO OFFSHORE MOBILE BAY. WITH STRONG HEATING AND INCREASING LOW LEVEL MOISTURE...AIR MASS S OF FRONT IS BECOMING MODERATELY UNSTABLE WITH MLCAPES TO 1500 J/KG OVER MUCH OF FL PENINSULA THIS AFTERNOON. GREATEST INSTABILITY WILL BE S FL WHERE DEWPOINTS AROUND 70F COUPLED WITH TEMPERATURES TO NEAR 90F RESULT IN MLCAPES TO 2500 J/KG. WITH 30-40KT OF DEEP LAYER SHEAR TYPICAL ACROSS FL THIS AFTERNOON...STORMS THAT ARE ABLE TO DEVELOP WILL HAVE SEVERE POTENTIAL. WLY COMPONENT WILL HOLD E COAST SEA BREEZE TO JUST INLAND WHICH WILL FOCUS BEST AREA OF STORM INITIATION BY MID AFTERNOON ERN FL PENINSULA. PRIMARY THREAT WILL BE LARGE HAIL GIVEN THE RELATIVELY STEEP LAPSE RATES OF 7C/KM...HOWEVER ISOLATED WIND DAMAGE/TORNADOES ARE ALSO POSSIBLE WHERE LOCALLY SURFACE CONVERGENCE IS ENHANCED ALONG SEA BREEZE FRONT AND CONVECTIVE BOUNDARIES. STORMS SHOULD WEAKEN/MOVE OFFSHORE BY 00Z ENDING SEVERE THREAT. ...NC COAST... SUFFICIENT LOW LEVEL MOISTURE EXPECTED TO REMAIN COASTAL COUNTIES THRU THE AFTERNOON TO MAINTAIN POTENTIAL FOR ISOLATED SEVERE THUNDERSTORM DEVELOPMENT. STRONG DEEP LAYER SHEAR AS 70KT MID LEVEL JET ROTATES ACROSS ERN CAROLINAS TO SUPPORT POTENTIAL FOR ROTATION OF STRONGEST STORMS. AGAIN THE STEEP LAPSE RATES AND RELATIVELY COOL AIR AT MID LEVELS WILL RESULT IN POSSIBLE SEVERE HAIL AND BRIEF DAMAGING WIND GUSTS THRU THE AFTERNOON. AS A RESULT HAVE UPGRADED THIS AREA TO A SLIGHT RISK. ...ERN AZ/WRN NM... SURFACE RIDGE PLAIN STATES WILL MAINTAIN ELY LOW LEVEL FLOW WRN NM INTO ERN AZ. MOISTURE ACCORDINGLY HAS SPREAD AS FAR W AS MOGOLLON RIM SWD IN AZ. THE STRONG HEATING AND STEEP LAPSE RATES IN PLACE ACROSS AZ COUPLED WITH INFLUX OF MOISTURE EXPECTED TO DEVELOP RELATIVELY HIGH BASED THUNDERSTORMS BY MID AFTERNOON OVER HIGHER TERRAIN OF ERN AZ/WRN NM. GUSTY WINDS WILL BE ASSOCIATED WITH THESE STORMS...PARTICULARLY AS THEY PROPAGATE INTO ADJACENT DESERTS VALLEYS BY LATE AFTERNOON. ..HALES/GRAMS.. 05/15/2006  From swody1 at goshenarc.org Tue May 16 00:44:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 15 May 2006 20:44:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160041 SWODY1 SPC AC 160039 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 PM CDT MON MAY 15 2006 VALID 160100Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM FAR SERN VA INTO SERN GA/NRN FL... ...ERN NC TO ERN GA... WATER VAPOR IMAGERY AND PLAN VIEW PROFILER/VWP DATA INDICATE A SHORT WAVE TROUGH AND ASSOCIATED 70 KT MID-LEVEL JET STREAK ROTATING NEWD THROUGH MEAN LONG WAVE TROUGH BASE INTO THE SERN STATES THIS EVENING. DEEP-LAYER FORCING FOR ASCENT IN LEFT EXIT REGION OF THIS JET STREAK HAS MAINTAINED A SURFACE LOW OVER E-CNTRL NC...WHICH IS FORECAST TO DEVELOP NEWD ALONG THE MIDDLE ATLANTIC COAST OVERNIGHT. AS A RESULT...COLD FRONT HAS EFFECTIVELY STALLED ACROSS S-CNTRL NC/N-CNTRL SC...WITH SOME EWD MOVEMENT NOTED FARTHER TO THE S OVER ERN GA. DESPITE RELATIVELY WEAK INSTABILITY OBSERVED ON THE 16/00Z MHX/CHS SOUNDINGS / I.E. SBCAPE OF 500-800 J/KG / AND THE ONSET OF NOCTURNAL COOLING...STRONG DEEP-LAYER SPEED SHEAR AND INCREASED DYNAMIC FORCING SHOULD MAINTAIN AN ENVIRONMENT SUPPORTIVE OF SEVERE STORMS FOR THE NEXT FEW HOURS FROM NERN SC INTO FAR SERN VA. WHILE LOCALLY DAMAGING WINDS AND SEVERE HAIL WILL BE THE PRIMARY SEVERE THREATS...A BRIEF TORNADO OR TWO WILL BE POSSIBLE WITH ANY EMBEDDED SUPERCELL STRUCTURES. FARTHER S...ISOLATED SEVERE STORMS WILL REMAIN POSSIBLE OVERNIGHT ALONG COLD FRONT MOVING THROUGH NRN FL...AS WELL AS WITH ANY CONVECTIVE CLUSTERS MOVING ONTO THE FL PENINSULA FROM THE ERN GULF OF MEXICO. ...SWRN NM... CLUSTERS OF TSTMS HAVE DEVELOPED LATE THIS AFTERNOON AND EARLY EVENING OVER PORTIONS OF W-CNTRL INTO SWRN NM...PERHAPS IN ASSOCIATION WITH A WEAK IMPULSE SHIFTING SEWD FROM THE 4-CORNERS REGION. 16/00Z ELP SOUNDING INDICATED THE PRESENCE OF STEEP LOW AND MID-LEVEL LAPSE RATES WHICH WERE CONTRIBUTING TO WEAK CONVECTIVE INSTABILITY WITH SBCAPES OF 200-300 J/KG. GIVEN THE STEEP LAPSE RATES AND DEEPLY MIXED BOUNDARY LAYER...SOME THREAT WILL EXIST FOR ISOLATED STRONG WIND GUSTS AND/OR SEVERE HAIL THROUGH THE REMAINDER OF THE EVENING. ..MEAD.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 05:57:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 01:57:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160554 SWODY1 SPC AC 160552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1252 AM CDT TUE MAY 16 2006 VALID 161200Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN FL PENINSULA... ...SYNOPSIS... AMPLIFIED LARGE-SCALE PATTERN WILL CONTINUE THROUGH THE DAY ONE PERIOD WITH LONG WAVE TROUGHING IN THE E AND A RIDGE INTO THE W. UPPER LOW NOW OVER THE CNTRL APPALACHIANS WILL LIFT NEWD TOWARD THE ST. LAWRENCE VALLEY WITH LONG WAVE TROUGH BECOMING MORE ELONGATED AS SHORT WAVE TROUGH DIGS SEWD ACROSS THE NRN GULF OF MEXICO. SEVERAL OTHER WEAK PERTURBATIONS ARE FORECAST TO ROTATE THROUGH THE LARGER-SCALE TROUGH FROM THE GREAT LAKES THROUGH THE MS RIVER VALLEY. IN THE LOW-LEVELS...SURFACE CYCLONE ATTENDANT TO UPPER LOW WILL DEVELOP NEWD THROUGH ERN NEW ENGLAND INTO THE ST. LAWRENCE VALLEY. TRAILING COLD FRONT WILL CONTINUE TO PUSH EWD INTO THE ATLANTIC WITH SWRN EXTENSION SLOWLY SAGGING SWD THROUGH THE CNTRL AND SRN FL PENINSULA. AN ADDITIONAL COLD FRONTAL SURGE IS FORECAST TO MOVE SWD THROUGH THE MID MS/LOWER OH VALLEYS SWD THROUGH THE MID SOUTH AND TN/LOWER MS VALLEYS. ...S FL... REGIONAL RADAR AND LIGHTNING DATA INDICATE ACTIVE CONVECTION ACROSS THE CNTRL AND ERN GULF BASIN...SUGGESTING THAT STORMS WILL LIKELY BE ONGOING AT 16/12Z WITHIN PRE-FRONTAL AIR MASS OVER THE CNTRL/SRN PENINSULA. LARGE-SCALE FORCING AHEAD OF MCV SHIFTING EWD THROUGH THE CNTRL GULF COUPLED WITH HEIGHT FALLS ASSOCIATED WITH SHORT WAVE TROUGH DIVING SEWD TOWARD THE NRN GULF SHOULD MAINTAIN CLUSTERS OF TSTMS THROUGH THE FORECAST PERIOD ALONG AND S OF FRONTAL ZONE. CONSIDERABLE CLOUDS AND PRECIPITATION WILL TEND TO LIMIT DESTABILIZATION...THOUGH THE PRESENCE OF A MOIST LOW-LEVEL AIR MASS /I.E. DEWPOINTS IN THE 60S TO LOWER 70S/ SHOULD CONTRIBUTE TO MLCAPES OF AROUND 1000 J/KG. MODESTLY STRONG DEEP-LAYER SPEED SHEAR WILL BE SUPPORTIVE OF A FEW SEVERE STORMS CAPABLE OF MAINLY LARGE HAIL AND DAMAGING WINDS. BEST POTENTIAL FOR SUPERCELLS AND A COUPLE OF TORNADOES WILL EXIST AHEAD OF SURFACE LOW WHICH IS FORECAST TO SHIFT EWD ACROSS THE SRN PENINSULA THIS EVENING OWING TO LOCALLY ENHANCED LOW-LEVEL SHEAR. ...MID SOUTH INTO LOWER MS VALLEY... COLD MID-LEVEL TEMPERATURES /I.E. -20 C AT 500 MB/ COUPLED WITH DIABATIC HEATING ARE EXPECTED TO CONTRIBUTE TO THE DEVELOPMENT OF STEEP LOW TO MID-LEVEL LAPSE RATES AND WEAK CONVECTIVE INSTABILITY AHEAD OF SECONDARY FRONTAL SURGE THIS AFTERNOON. A FEW OF THE STRONGER STORMS WILL BE CAPABLE OF HAIL /SOME APPROACHING SEVERE LEVELS/ AND GUSTY WINDS INTO THE EVENING HOURS. ...MIDWEST... A SECONDARY REGION OF TSTMS WILL BE POSSIBLE TODAY AHEAD OF VORTICITY LOBE ROTATING SEWD OUT OF THE GREAT LAKES. IT APPEARS THAT CLOUD COVER WILL BE MORE WIDESPREAD THAN POINTS TO THE S...EFFECTIVELY LIMITING LAPSE RATES AND RESULTANT DEGREE OF DESTABILIZATION. NONETHELESS...SOME SMALL HAIL WILL BE POSSIBLE WITH THE MORE INTENSE STORMS. ...ERN NEW ENGLAND... DEEP-LAYER FORCING WILL INCREASE ACROSS THE REGION TODAY WITH APPROACH OF SURFACE AND UPPER-LEVEL LOWS. TSTMS ARE EXPECTED TO BECOME INCREASINGLY LIKELY BY AFTERNOON FROM VICINITY OF LOW SWD ALONG COLD FRONT. CURRENTLY...IT APPEARS THAT INSTABILITY WILL REMAIN QUITE WEAK...THOUGH THE STRONG FORCING FOR ASCENT AND INCREASING VERTICAL SHEAR MAY SUPPORT A FEW VIGOROUS STORMS CAPABLE OF GUSTY WINDS AND SMALL HAIL. ..MEAD/TAYLOR.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 12:31:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 08:31:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161228 SWODY1 SPC AC 161227 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0727 AM CDT TUE MAY 16 2006 VALID 161300Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN FL PENINSULA... ...FL... UPPER TROUGH WILL REMAIN OVER THE EASTERN STATES TODAY...ALTHOUGH PRIMARY UPPER LOW CENTER WILL BEGIN SHIFTING NORTHEASTWARD INTO NEW ENGLAND. MORNING SATELLITE AND RADAR IMAGERY SHOW WIDESPREAD CONVECTION OVER THE EASTERN GULF OF MEXICO AND THE FL PENINSULA. THIS ACTIVITY WILL LIKELY CONTINUE TO AFFECT FL FOR MUCH OF THE DAY. LOW AND MID LEVEL WINDS STRENGTHEN SLIGHTLY DURING THE DAY...MAINTAINING VERTICAL SHEAR PARAMETERS FAVORABLE FOR ORGANIZED AND ISOLATED SEVERE STORMS. THE MAIN FORECAST QUESTION INVOLVES THE AMOUNT OF INSTABILITY THAT WILL DEVELOP ACROSS THIS REGION TODAY. WIDESPREAD CLOUDINESS AND SCATTERED PRECIP WILL LIMIT DIURNAL HEATING...WITH POCKETS OF AFTERNOON MLCAPE VALUES AROUND 1500 J/KG. ISOLATED STORMS IN THIS REGION WILL BE CAPABLE OF WET MICROBURSTS AND HAIL. ...MS/TN VALLEY... LATEST WATER VAPOR IMAGERY SHOWS WELL-DEFINED UPPER SHORTWAVE TROUGH ROTATING AROUND UPPER LOW ACROSS IL/MO. THIS FEATURE IS EXPECTED TO MOVE SOUTHWARD INTO THE TN AND MIDDLE MS VALLEYS BY THIS AFTERNOON. COOL MID LEVEL TEMPERATURES AND RELATIVELY STEEP LOW/MID LEVEL LAPSE RATES WILL HELP DESTABILIZE AIR MASS...ALTHOUGH SURFACE DEWPOINTS ARE LIKELY TO REMAIN BELOW 50F. AFTERNOON CAPE VALUES OF UP TO 1000 J/KG WILL AID IN THE DEVELOPMENT OF ISOLATED TO SCATTERED THUNDERSTORMS. THERMODYNAMIC PROFILES SUGGEST HAIL WILL BE POSSIBLE IN STRONGER CELLS. ORGANIZED SEVERE STORMS DO NOT APPEAR LIKELY AT THIS TIME. ..HART/TAYLOR.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 16:11:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 12:11:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161602 SWODY1 SPC AC 161601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1101 AM CDT TUE MAY 16 2006 VALID 161630Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS SOUTHERN FL... ...SRN FL... LARGE TROUGH IN E AND RIDGE IN THE W WITH UNSEASONABLY STRONG WESTERLIES ACROSS FL PENINSULA. COLD FRONTAL ZONE CENTRAL FL IS MOVING ONLY VERY SLOWLY SWD. SATELLITE AND RADAR INDICATE EXTENSIVE CLOUDINESS AND CONVECTION CONTINUING EXTREME S FL SWD TO WRN CUBA AHEAD OF A WEAK S/WV TROUGH CURRENTLY CENTRAL GULF OF MEXICO. WHILE DEEP LAYER SHEAR REMAINS SUPPORTIVE OF ORGANIZED THUNDERSTORMS S FL TO S OF COLD FRONT...THE SEVERE THREAT WILL BE DEPENDENT ON AMOUNT OF INSTABILITY THAT CAN DEVELOP THIS AFTERNOON. HIGHER THREAT FOR SEVERE STORMS APPEARS TO BE PRIMARILY ERN PORTION OF S FL WHERE INSTABILITY AND LOW LEVEL MOISTURE IS GREATEST. MLCAPES COULD CLIMB TO NEAR 2000 J/KG SE COASTAL AREA WHICH COUPLED WITH CONVERGENCE ALONG THE SEA BREEZE FRONT WOULD ENHANCE POTENTIAL FOR SEVERE STORMS BY MID AFTERNOON. ADDITIONALLY DEEPER TROPICAL MOISTURE ACROSS KEYS WILL CONTINUE TO SUPPORT PRIMARILY MULTICELL STORMS ALONG WITH DAMAGING WIND POTENTIAL. ...MS/TN VALLEY REGION... S/WV IMPULSE ROTATING SWD THRU LOWER MO VALLEY AROUND ERN U.S. TROUGH WILL AID IN CONVECTIVE DEVELOPMENT THIS AFTERNOON. HEATING AND STEEP LOW/MID LEVEL LAPSE RATES WILL DESTABILIZE AIR MASS TN VALLEY AREA WWD TO MS VALLEY. THUNDERSTORMS WILL INCREASE THRU THE AFTERNOON WITH HEATING...HOWEVER THE RELATIVE WEAK SHEAR WILL LIMIT SEVERE THREAT TO A FEW HAIL EVENTS. ..HALES/CARBIN.. 05/16/2006  From swody1 at goshenarc.org Tue May 16 19:58:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 15:58:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161953 SWODY1 SPC AC 161952 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0252 PM CDT TUE MAY 16 2006 VALID 162000Z - 171200Z ...NO SVR TSTM AREAS FORECAST... ...LOWER MS/TN VALLEYS... COLDEST MID LEVEL TEMPERATURES ARE SETTLING INTO THE BASE OF THE TROUGH OVER THE LOWER MS VALLEY WHERE H5 READINGS ARE ROUGHLY -20C. RESULTANT THERMODYNAMIC PROFILES ARE QUITE STEEP GIVEN STRONG BOUNDARY LAYER HEATING...LOWEST 3KM LAPSE RATES ON THE ORDER OF 8-8.5C/KM FROM MIDDLE TN...SWWD INTO NRN LA. NUMEROUS SHOWERS AND THUNDERSTORMS HAVE DEVELOPED BENEATH THIS COLD POCKET...IMMEDIATELY AHEAD OF UPPER VORT ROTATING SEWD ACROSS MO...WHERE INCREASING NWLY FLOW IS SUFFICIENTLY STRONG ENOUGH TO MAINTAIN MOVEMENT OF PULSE-MULTI CELL UPDRAFTS. FORECAST SOUNDINGS ACROSS THE LOWER MS/TN VALLEYS SUGGEST SOME HAIL WILL DEVELOP WITHIN THE STRONGEST UPDRAFTS BUT MUCH OF THIS ACTIVITY SHOULD REMAIN AOB ORGANIZED SEVERE LEVELS. ...IA... LATEST WV IMAGERY DEPICTS A FAIRLY WELL DEFINED UPPER VORT ALONG THE IL/IA BORDER...ROTATING SSWWD ALONG THE MS RIVER. THIS FEATURE APPEARS PARTLY RESPONSIBLE FOR RECENT INCREASE IN CONVECTION FROM NEAR LSE TO OTM. SUFFICIENT INSTABILITY EXISTS ACROSS THIS REGION FOR MARGINALLY SEVERE HAIL WITH THE STRONGEST UPDRAFTS THROUGH EARLY EVENING. ...SWRN U.S... CONSIDERABLE AMOUNT OF CONVECTION HAS RECENTLY DEVELOPED WITHIN MOIST HIGH LEVEL DEFORMATION ZONE FROM NWRN AZ INTO SWRN NM. STRONG HEATING OVER THE HIGHER TERRAIN HAS CERTAINLY AIDED RECENT UPDRAFT DEVELOPMENT WHICH APPEARS TO BE DRIFTING SWWD TOWARD THE LOWER ELEVATIONS. MUCH OF THIS ACTIVITY SHOULD HOWEVER STRUGGLE TO GENERATE SIGNIFICANT PRECIPITATION WHICH MAY ULTIMATELY LIMIT STRONGEST STORMS TO BRIEF BOUTS OF GUSTY WINDS OR SOME HAIL. ..DARROW.. 05/16/2006  From swody1 at goshenarc.org Wed May 17 01:02:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 16 May 2006 21:02:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170058 SWODY1 SPC AC 170056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT TUE MAY 16 2006 VALID 170100Z - 171200Z ...NO SVR TSTM AREAS FORECAST... ...SIERRA NEVADAS... MOST VIGOROUS CONVECTION AS OF 0030Z WAS OCCURRING NW OF RNO ALONG WRN EDGE OF MID-LEVEL MOISTURE PLUME PER WATER VAPOR IMAGERY. THIS MOISTURE COUPLED WITH A DEEP AND WELL-MIXED BOUNDARY LAYER WAS CONTRIBUTING TO SBCAPES OF AROUND 600 J/KG BASED ON 17/00Z RNO SOUNDING. SOME MARGINALLY SEVERE HAIL AND/OR LOCALLY STRONG WIND GUSTS WILL BE POSSIBLE THROUGH 03Z GIVEN THE RELATIVELY STEEP LOW AND MID-LEVEL LAPSE RATES AND STRONG EVAPORATIVE COOLING POTENTIAL IN THE SUB-CLOUD LAYER. ...AZ... REGIONAL RADAR IMAGERY INDICATES THAT TSTMS WHICH DEVELOPED EARLIER THIS AFTERNOON ALONG THE MOGOLLON RIM HAVE RECENTLY WEAKENED WITH A CONVECTIVE OUTFLOW BOUNDARY PUSHING SEWD INTO THE LOWER DESERT FLOOR. 17/00Z TUS SOUNDING INDICATED A DEEPLY MIXED AND QUITE DRY BOUNDARY LAYER WITH MARGINAL CONVECTIVE INSTABILITY. SOME POTENTIAL FOR STORM RE-DEVELOPMENT WILL EXIST ALONG THIS BOUNDARY INTO THE EVENING WITH LOCALLY GUSTY WINDS POSSIBLE. ...TN/MS/AL... LOW TOPPED CONVECTIVE LINE IS IN PROGRESS THIS EVENING ALONG PRESSURE TROUGH/WEAK COLD FRONT FROM W OF CSV TO N OF GWO WITHIN ENVIRONMENT OF MODEST LAPSE RATES AND WEAK INSTABILITY. FORCING FOR ASCENT AHEAD OF VORTICITY MAXIMUM TRANSLATING SEWD INTO THE CNTRL GULF STATES SHOULD MAINTAIN AT LEAST SOME OF THIS ACTIVE CONVECTION FOR THE NEXT SEVERAL HOURS. THE LOSS OF DAYTIME HEATING AND FURTHER WEAKENING OF ALREADY MARGINAL INSTABILITY SHOULD PRECLUDE ANY SEVERE THREAT...THOUGH GUSTY WINDS AND SMALL HAIL WILL REMAIN POSSIBLE WITH THE STRONGEST STORMS. ...MIDWEST... A COUPLE OF N-S ORIENTED TSTM BANDS ARE OCCURRING THIS EVENING FROM ERN IA INTO CNTRL MO AND FROM SRN WI INTO WRN AND CNTRL PARTS OF IL AHEAD OF MID-LEVEL IMPULSE DIVING SWD THROUGH THE REGION. HERE TOO...17/00Z SOUNDINGS INDICATED MODEST LAPSE RATES AND WEAK INSTABILITY WHICH WILL SUPPORT ONGOING STORMS INTO THE EVENING. SMALL HAIL AND LOCALLY GUSTY WINDS WILL REMAIN POSSIBLE FOR THE NEXT FEW HOURS....PRIOR TO STORMS WEAKENING WITH THE ONSET OF NOCTURNAL COOLING. ..MEAD.. 05/17/2006  From swody1 at goshenarc.org Fri May 19 05:41:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 01:41:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190539 SWODY1 SPC AC 190537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1237 AM CDT FRI MAY 19 2006 VALID 191200Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS OZARKS REGION TO TN VALLEY.... ...SYNOPSIS... VERY STABLE LARGE SCALE PATTERN WILL FEATURE SYNOPTIC RIDGE OVER WRN NORTH AMERICA AND TROUGH IN ERN PORTIONS CONUS/CANADA. SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN SASK -- SHOULD AMPLIFY AND DIG SEWD WHILE LEAVING MEAN RIDGE POSITION. AS THIS OCCURS...PRONOUNCED MIDDLE-UPPER LEVEL LOW PRESENTLY OVER LE REGION IS FCST TO MOVE EWD THEN NNEWD ACROSS NY AND SRN QUE. WEAK PERTURBATION OVER NRN HIGH PLAINS IS FCST TO MOVE SEWD ACROSS CENTRAL PLAINS AND OZARKS. ASSOCIATED FRONTAL-WAVE LOW -- NOW WEAKLY EVIDENT OVER ND -- IS EXPECTED TO STRENGTHEN SOMEWHAT AS IT PROPAGATES SEWD ALONG CURRENTLY QUASISTATIONARY BAROCLINIC ZONE. THIS LOW SHOULD CROSS OZARKS REGION DURING LATE AFTERNOON/EARLY EVENING. ...OZARKS REGION TO TN VALLEY... WEAKENING CINH AND LIFT NEAR FRONT WILL SUPPORT TSTM DEVELOPMENT DURING AFTERNOON...SHIFTING SEWD AND PERHAPS EXPANDING IN COVERAGE THROUGH LATE EVENING BEFORE DIMINISHING. DAMAGING GUSTS AND LARGE HAIL ARE ANTICIPATED. TORNADO POTENTIAL IS MORE MRGL...UNCERTAIN AND STRONGLY CONDITIONAL ON MESOSCALE TO STORM SCALE PROCESSES. ETA INITIALIZED TOO HIGH ON SFC MOISTURE IN THIS AREA AND UPSTREAM...AND ITS PROGGED DEW POINT AND CAPE VALUES APPEAR TOO LARGE. HOWEVER...WITH EVAPOTRANSPIRATIVE SUPPORT...SFC DEW POINTS MAINLY FROM UPPER 50S TO MID 60S F ARE POSSIBLE ACROSS THIS AREA...PER WRF SOUNDINGS. LOW-MIDLEVEL LAPSE RATES SHOULD BE STEEPEST OVER MO/AR AT 8-9 DEG C/KM...WEAKENING WITH SEWD EXTENT ALONG FRONTAL ZONE. THIS COMBINED WITH DIABATIC HEATING WILL SUPPORT AFTERNOON MLCAPES NEAR 3000 J/KG...ALSO DIMINISHING WITH SEWD EXTENT...BUT SUPPORTING SEVERE POTENTIAL THROUGH NEAR-FRONTAL CORRIDOR FROM OZARKS SEWD ACROSS WRN/MID TN GIVEN FAVORABLE VERTICAL SHEAR PROFILES EXPECTED. SFC WINDS SHOULD RANGE FROM SWLY IN WARM SECTOR TO LIGHT/VARIABLE IN FRONTAL ZONE...AND PERHAPS SLY-SELY JUST SE OF SFC LOW. THIS WILL SUPPORT LARGE VARIATION IN LOW LEVEL SHEAR PROFILES...WITH 0-3 KM SRH 100-400 J/KG WHERE THERE IS SFC-BASED BUOYANCY...AND EFFECTIVE BULK VALUES 35-55 KT OVER MUCH OF OUTLOOK AREA. SOME SUPERCELLS AND BOW ECHOES ARE POSSIBLE. ...ERN NJ TO SRN/CENTRAL NEW ENGLAND AREA... AIR MASS MAY HEAT/RECOVER SUFFICIENTLY AFTER MORNING CLOUDS/PRECIP TO PERMIT ADDITIONAL TSTMS DURING AFTERNOON...SOME OF WHICH MAY PRODUCE HAIL. AS MID/UPPER LEVEL LOW APCHS...MIDLEVEL ASCENT/COOLING SHOULD CONTRIBUTE TO STEEPENED LAPSE RATES. CINH SHOULD BE SMALL...REQUIRING ONLY WEAK SFC HEATING TO CONVECT IN FCST SOUNDINGS WITH MLCAPES UP TO ABOUT 500 J/KG. UNCERTAINTIES ABOUT SPEED/STRENGTH OF DIURNAL DESTABILIZATION PRECLUDE CATEGORICAL OUTLOOK ATTM. STRONG-SVR TSTM POTENTIAL SHOULD DIMINISH MARKEDLY WITH LOSS OF AFTERNOON INSOLATION. ...NWRN CONUS... WIDELY SCATTERED AFTERNOON TSTMS AGAIN ARE EXPECTED TO FORM...INITIALLY OVER HEATED HIGHER TERRAIN WITH DEVELOPMENT/PROPAGATION INTO VALLEYS AND BASINS. STRONGEST SFC HEATING/MIXING AND AT LEAST MRGLLY FAVORABLE SFC MOISTURE IS EXPECTED OVER THIS AREA...AIDED BY EVAPOTRANSPIRATION OF SOME PRECIP THAT FELL ON THURSDAY. LOW-MIDLEVEL LAPSE RATES APCHG DRY ADIABATIC WILL FURTHER CONTRIBUTE TO MLCAPES GENERALLY 300-800 J/KG. ..EDWARDS.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 12:58:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 08:58:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191254 SWODY1 SPC AC 191253 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 AM CDT FRI MAY 19 2006 VALID 191300Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE LWR MO VLY INTO THE TN VLY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER INTERIOR PARTS OF THE PAC NW... ...SYNOPSIS... AMPLIFIED PATTERN WILL CONTINUE OVER THE LWR 48 THIS PERIOD...WITH A RIDGE OVER THE WRN SLOPES OF THE RCKYS AND A TROUGH FROM WRN HUDSON BAY TO THE MID ATLANTIC CST. LEAD IMPULSE ASSOCIATED WITH E PACIFIC TROUGH...NOW OFF THE NRN CA CST...SHOULD EJECT NNE INTO THE LWR COLUMBIA BASIN BY 12Z SATURDAY AS UPSTREAM DISTURBANCE NOW NEAR 40N/135W DROPS SSE TO REPLACE IT. FARTHER E...SHORTWAVE IMPULSES ARE SOMEWHAT HARDER TO DISCERN IN THE NW FLOW ACROSS THE PLAINS. SATELLITE SUGGESTS THAT ONE DISTURBANCE ATTM IS OVER NW MO...WITH ANOTHER OVER CNTRL ND. BOTH SHOULD SHEAR SEWD TODAY AS WRN PA UPR LOW LIFTS NE INTO THE ADIRONDACKS. ...LWR MO VLY INTO TN VLY... STATIONARY FRONTAL ZONE EXTENDING SEWD FROM THE LWR MO VLY INTO TN AND THE SRN APLCNS WILL BE THE FOCUS FOR SCATTERED STORMS THIS PERIOD. WHILE TIMING WITH RESPECT TO SHORTWAVE FEATURES DOES NOT APPEAR TO BE FAVORABLE...WEAKENING CINH PROVIDED BY SURFACE HEATING AND LIFT NEAR BOUNDARY SHOULD SUPPORT DEVELOPMENT OVER MO/AR AND W TN DURING THE AFTERNOON. THIS ACTIVITY SHOULD MOVE/DEVELOP ESE AND MAY EXPAND IN COVERAGE THROUGH LATE EVENING BEFORE DIMINISHING. HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE...BUT TORNADO THREAT APPEARS MARGINAL GIVEN LIMITED MOISTURE AVAILABILITY. CURRENT SURFACE OBSERVATIONS...GOES MICROWAVE SOUNDER PWS...AND AIR MASS MOVEMENTS IN RECENT DAYS SUGGEST THAT THE MODELS ARE OVER-FORECASTING BOUNDARY LAYER MOISTURE INVOF AFOREMENTIONED FRONT. EVEN ACCOUNTING FOR MID-MAY EVAPOTRANSPIRATION...EXPECT THAT SURFACE DEWPOINTS IN WELL MIXED ENVIRONMENT WILL AT BEST REMAIN LIMITED TO THE LOW TO MID 50S FROM MO INTO NRN AR...WITH LESSER VALUES EXTENDING E/SE INTO THE TN VLY. NEVERTHELESS...RELATIVELY COOL MID LEVEL TEMPERATURES AND STRONG SURFACE HEATING WILL CONTRIBUTE TO AN ENVIRONMENT OF STEEP /8-9 DEG C PER KM/ LOW-MID LEVEL LAPSE RATES OVER MO/AR. COUPLED WITH EVEN MODEST MOISTURE...THIS SHOULD YIELD MUCAPE OF 1000-1500 J/KG. GIVEN EXPECTED FAVORABLE VERTICAL SHEAR PROFILES ASSOCIATED WITH NWLY MID/UPR LEVEL FLOW...AND POSSIBLE INCREASE IN LARGE SCALE ASCENT TO BE PROVIDED LATER TODAY BY UPR IMPULSE NOW IN ND...SETUP COULD SUPPORT A FEW ROTATING STORMS WITH HAIL/HIGH WIND. SFC WINDS WILL BE VARIABLE...RANGING FROM SWLY IN WARM SECTOR TO SLY-SELY JUST E OF FRONT...RESULTING IN A LARGE VARIATION IN LOW LEVEL SHEAR PROFILES. BUT BOWING STRUCTURES WILL BE POSSIBLE WITH ANY STORMS THAT DO FORM GIVEN MODERATE MEAN FLOW AND LIKELY 20 DEG F TEMPERATURE-DEWPOINT SPREADS. ...INTERIOR PAC NW... WIND PROFILES WILL STRENGTHEN RELATIVE TO RECENT DAYS OVER INTERIOR PORTIONS OF ORE/WA AND WRN ID LATER TODAY AS E PACIFIC SHORTWAVE IMPULSE LIFTS NNE TOWARD REGION. SURFACE HEATING... POSSIBLY AIDED BY LARGE SCALE ASCENT FROM SHORTWAVE...LIKELY WILL YIELD SCATTERED AFTERNOON/EVENING STORMS OVER CNTRL/ERN ORE/WA AND POSSIBLY WRN ID....INITIALLY OVER THE HIGHER TERRAIN. THE MODERATE...LARGELY UNIDIRECTIONAL SSWLY CLOUD LAYER FLOW MAY SUPPORT DEVELOPMENT OF ONE OR MORE BANDS OF STORMS. COUPLED WITH LARGE TEMPERATURE-DEWPOINT SPREADS/STEEP LOW TO MID LEVEL LAPSE RATES...SOME OF THESE MAY CONTAINING BOWING SEGMENTS WITH HIGH WIND/MARGINALLY SEVERE HAIL. LOW LEVEL MOISTURE IN SOME SPOTS WILL BE AUGMENTED BY RECYCLING OF MOISTURE FROM OVERNIGHT CONVECTION...AND COULD LOCALLY BOOST AFTERNOON MUCAPE TO 1000 J/KG. ...NRN NJ TO SRN/CNTRL NEW ENGLAND... LINGERING AXIS OF LOW LEVEL CONFLUENCE IN SW QUADRANT OF RI/ERN MA SURFACE LOW MAY BE A FOCUS FOR TSTM DEVELOPMENT LATER TODAY AS MODEST AIR MASS RECOVERY OCCURS IN WAKE OF DENSE MORNING CLOUDS/PRECIP. GIVEN COLD MID LEVEL TEMPERATURES /BLO MINUS 20C AT 500 MB/... SOME OF THESE MAY PRODUCE HAIL AS MLCAPE CLIMBS TO AROUND 500 J/KG. STRONG-SVR TSTM POTENTIAL SHOULD DIMINISH WITH ONSET OF DIURNAL COOLING. ..CORFIDI/TAYLOR.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 16:45:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 12:45:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191633 SWODY1 SPC AC 191632 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1132 AM CDT FRI MAY 19 2006 VALID 191630Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE LOWER MO RIVER VALLEY INTO THE TN RIVER VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN INTERMOUNTAIN WEST... ...LOWER MO RIVER VALLEY INTO THE TN VALLEY... SURFACE ANALYSES INDICATE OUTFLOW BOUNDARY/STATIONARY FRONT EXTENDING SE-NW FROM THE MID SOUTH INTO CENTRAL/ERN MO. MORNING CONVECTION APPEARS TO BE TIED TO WEAK SHORTWAVE TROUGH NOW MOVING ACROSS THE LOWER OH RIVER VALLEY. WITH PERSISTENT SURFACE HEATING AHEAD OF THESE STORMS...ACTIVITY MAY INCREASE AND BECOME MARGINALLY SEVERE INTO WRN TN/NERN MS/NRN AL THIS AFTERNOON ONCE CAP WEAKENS. HOWEVER...MORE VIGOROUS ACTIVITY SHOULD DEVELOP AHEAD OF UPSTREAM SHORTWAVE TROUGH NOW MOVING SEWD ACROSS THE DAKOTAS. MODELS CONTINUE TO DRASTICALLY INCREASE SURFACE DEW POINTS AHEAD OF ADVANCING SURFACE COLD FRONT ASSOCIATED WITH APPROACHING SYSTEM. EXPECT NON-ADVECTIVE PROCESSES WILL ALLOW SOME INCREASE IN SURFACE DEW POINTS THROUGH THE AFTERNOON INTO SRN MO/NRN AR WITH DEW POINTS AROUND 60F POSSIBLE ACROSS THIS REGION. MODIFIED FORECAST SOUNDINGS INDICATE HEATING WILL SUPPORT MARGINAL TO MODERATE INSTABILITY WITH MLCAPES AROUND 1O00 J/KG LATE TODAY...WITH RATHER STRONG DEEP LAYER SHEAR UNDER NWLY FLOW ALOFT. EXPECT DEVELOPMENT WILL OCCUR BETWEEN 21-00Z NEAR TRIPLE POINT SURFACE LOW OVER MO AND POSSIBLY ALONG OUTFLOW BOUNDARY/WARM FRONT INTO THE LOWER OH RIVER VALLEY. WLY LLJ WILL BE SUSTAINED/INCREASE ACROSS THE MID SOUTH LATER TODAY AND THIS EVENING SUGGESTING ACTIVITY WILL INCREASE/SPREAD ESEWD INTO THE EARLY NIGHTTIME HOURS. DAMAGING WINDS AND LARGE HAIL WILL BE PRIMARY SEVERE THREATS. ...NRN INTERMOUNTAIN REGION INTO PORTIONS OF THE PAC NW... SLY FLOW ALOFT WILL STRENGTHEN ACROSS THIS REGION AHEAD OF SHORTWAVE TROUGH NOW APPROACHING THE PAC NW COAST. SURFACE DEW POINTS REMAIN IN THE LOWER 50S ALONG AND EAST OF THE CASCADES...SUGGESTING MODERATE INSTABILITY WILL DEVELOP OVER LOWER ELEVATIONS TODAY GIVEN RELATIVELY STEEP LAPSE RATES IN PLACE. DEVELOPMENT SHOULD INCREASE ALONG AND NEAR HIGHER TERRAIN FROM FAR NRN CA INTO CENTRAL ORE/WA BY 21Z...WITH STORMS PERSISTING AND STRENGTHENING AS THEY ENCOUNTER MODERATE INSTABILITY THROUGH THE EARLY EVENING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR SUFFICIENT FOR ORGANIZED LINES/SUPERCELLS WHICH WILL INCREASE THE THREAT OF LARGE HAIL/DAMAGING WINDS. TORNADO THREAT SHOULD BE MITIGATED BY RELATIVELY WEAK LOW LEVEL SHEAR FORECAST. ...COASTAL NEW ENGLAND... DEEP UPPER LOW IS SUSTAINING STRONG...FAST MOVING STORMS NOW APPROACHING THE ME COAST ALONG NWRN EDGE OF MARGINAL SBCAPE AXIS. SHEAR AND DEEP ASCENT REMAIN QUITE STRONG AND MAY ALLOW BRIEF SEVERE WIND GUSTS WITH THESE LINES AS THEY MOVE INLAND. FURTHER DEVELOPMENT MAY OCCUR DURING THE AFTERNOON AND ALSO LIFT QUICKLY NWD ALONG THE NEW ENGLAND COAST. FROM THE LOWER HUDSON INTO THE CT RIVER VALLEYS...ISOLATED HAIL...SOME NEAR SEVERE LIMITS...MAY ACCOMPANY STRONGER CELLS DEVELOPING IN CLOSER PROXIMITY TO UPPER LEVEL LOW/MID LEVEL COLD POCKET NOW MOVING INTO THE NERN U.S. ..EVANS/GUYER.. 05/19/2006  From swody1 at goshenarc.org Fri May 19 20:01:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 16:01:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191958 SWODY1 SPC AC 191957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT FRI MAY 19 2006 VALID 192000Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID MS VALLEY AND TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE PACIFIC NORTHWEST... ...MID MS VALLEY/TN VALLEY... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BELT OF NWLY FLOW ACROSS THE MID MS AND TN VALLEYS. AT THE SFC..A STRONG MOISTURE GRADIENT EXISTS FROM ERN MO EXTENDING SEWD INTO WRN TN AND WRN AL. OBJECTIVE ANALYSIS HAS THE MAIN INSTABILITY AXIS FROM NWRN AR ACROSS SCNTRL MO. ALTHOUGH THIS AREA IS CURRENTLY CAPPED...LOW-LEVEL CONVERGENCE SHOULD INCREASE AS A COLD FRONT MOVES SWD ACROSS MO THIS AFTERNOON. THIS SHOULD BE ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG AND SOUTHEAST OF THE BOUNDARY LATE THIS AFTERNOON. OTHER STORMS WILL CONTINUE TO INITIATE IN WRN KY AND WRN TN. MODEL FORECASTS ARE GENERALLY CONSISTENT...DEVELOPING AN MCS IN SERN MO AND MOVING THE MCS SEWD ACROSS WRN KY AND TN THIS EVENING. FORECAST SOUNDINGS THIS EVENING ACROSS THE SLIGHT RISK AREA SHOW STRONG VERTICAL SHEAR PROFILES. THIS SHOULD BE FAVORABLE FOR SUPERCELLS ESPECIALLY EARLY IN THE DEVELOPMENT OF THE MCS OVER SERN MO WHERE INSTABILITY IS MAXIMIZED. DUE TO STEEP LAPSE RATES ACROSS MO AND AR...THIS AREA WILL HAVE THE GREATEST POTENTIAL FOR LARGE HAIL. AS THE MCS ORGANIZES AND MOVES SEWD INTO WRN KY AND WRN TN...A WIND DAMAGE THREAT WILL ALSO BE LIKELY WITH THE STRONGER MULTICELL CLUSTERS. THE SEVERE THREAT SHOULD GRADUALLY LESSEN AS THE MCS TRACKS SEWD ACROSS THE TN VALLEY DURING THE OVERNIGHT PERIOD. ...PACIFIC NORTHWEST... WATER VAPOR IMAGERY CURRENTLY SHOWS A HIGHLY AMPLIFIED UPPER-LEVEL TROUGH JUST OFF THE WEST COAST. AS THIS TROUGH MOVES SLOWLY TOWARD THE COAST THIS AFTERNOON...LARGE-SCALE ASCENT WILL INCREASE ACROSS THE PACIFIC NORTHWEST. THIS SHOULD CONTINUE TO SUPPORT THUNDERSTORM DEVELOPMENT ACROSS THE SLIGHT RISK AREA THIS AFTERNOON. OBJECTIVE ANALYSIS CURRENTLY SHOWS AN AXIS OF MODERATE INSTABILITY FROM WRN ID EXTENDING NWD INTO NRN ORE. THIS COMBINED WITH MODERATE VERTICAL SHEAR SHOWN ON REGIONAL WSR-88D VWPS SHOULD BE FAVORABLE FOR A FEW SUPERCELL STORMS IN ERN ORE...WRN ID AND SERN WA THIS AFTERNOON. THE INSTABILITY AND STEEP LAPSE RATES SHOWN ON OBJECTIVE ANALYSIS SUGGEST HAIL AND WIND DAMAGE WILL BE POSSIBLE WITH THE STRONGER STORMS. ...NEW ENGLAND STATES... WATER VAPOR IMAGERY CURRENTLY SHOWS THE CENTER OF AN UPPER-LOW OVER SERN NY ATTM. THUNDERSTORMS ARE DEVELOPING JUST AHEAD OF THE TRACK OF THE UPPER-LOW. COLD AIR ALOFT...STEEP LAPSE RATES AND STRONG LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-LOW WILL BE FAVORABLE FOR STRONG WIND GUSTS AND HAIL WITH THE STRONGER CELLS LATE THIS AFTERNOON. ..BROYLES.. 05/19/2006  From swody1 at goshenarc.org Sat May 20 01:12:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 19 May 2006 21:12:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200108 SWODY1 SPC AC 200107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT FRI MAY 19 2006 VALID 200100Z - 201200Z ...THERE IS A SLGT RISK OF SVR TSTMS NERN ORE...SERN WA...NRN ID...EXTREME WRN MT... ...THERE IS A SLGT RISK OF SVR TSTMS ERN MO/SRN IL TO NRN AL/SWRN TN... ...SYNOPSIS... STABLE LONGWAVE PATTERN WILL SUPPORT CONTINUANCE OF WRN MEAN RIDGE AND ERN TROUGH. AS STRONG SHORTWAVE TROUGH DIGS SEWD FROM NRN MB TO NWRN ONT...UPPER LOW NOW OVER NEW ENGLAND WILL EJECT NNEWD OVER ST LAWRENCE RIVER VALLEY OF QUE. SUBTLE SHORTWAVE TROUGH AND ASSOCIATED MID-UPPER SPEED MAX WILL CONTINUE MOVING SEWD ACROSS LOWER MO VALLEY REGION TOWARD TN VALLEY OVERNIGHT...AS WILL ASSOCIATED SFC FRONTAL-WAVE LOW...ALONG NW-SE ALIGNED AND QUASISTATIONARY BAROCLINIC ZONE. MEANWHILE....DEEP-LAYER SSWLY FLOW WILL CONTINUE OVER PACIFIC NW AND NRN ROCKIES...WITH WEAK/EMBEDDED PERTURBATIONS MOVING INTO MEAN RIDGE POSITION. ...NWRN CONUS... SERN WA MCS WILL REMAIN PRIMARY FOCUS FOR SVR POTENTIAL AS IT MOVES NEWD WITH DAMAGING GUSTS AND OCCASIONAL HAIL POSSIBLE. ADDITIONAL SVR WIND/HAIL POTENTIAL REMAINS EWD TOWARD ID/MT BORDER REGION. REF WW 364 AND RELATED MESOSCALE DISCUSSIONS FOR NEAR-TERM THREATS. GEG SOUNDING REMAINS MISSING BECAUSE OF RAOB EQUIPMENT UPGRADES...HOWEVER MODIFIED BOI RAOB AND RUC FCST SOUNDINGS SUGGEST POCKETS OF 500-1000 J/KG MLCAPES WILL SUPPORT ACTIVITY AMIDST LOW-MIDLEVEL LAPSE RATES APCHG 9 DEG C/KM...WITH 40S-50S F SFC DEW POINTS. SVR RISK IS STRONGLY TIED TO PRESENCE OF DEEPLY HEATED/WELL-MIXED BOUNDARY LAYER IN INFLOW REGION OF TSTMS...AS WELL AS LIFT GENERATED ALONG LEADING EDGES OF COLD POOLS FROM MCS...AND SHOULD DIMINISH MARKEDLY AFTER SUNSET WHEN DIABATIC SFC COOLING WILL BE STRONGEST. ...LOWER MO VALLEY...OZARKS TO TN VALLEY REGION... CHANCE STILL EXISTS FOR SFC-BASED DEVELOPMENT OF SVR TSTMS INVOF SFC LOW AND FRONTAL ZONE OVER ERN MO FOR ANOTHER 1-2 HOURS...SUPPORTED BY FRONTAL LIFT...50-60 KT EFFECTIVE SHEAR...200-300 J/KG OF 0-3 KM SRH ALONG FRONT...AND MLCAPES APPROXIMATELY 1500 J/KG. SPECIFIC MORPHOLOGY AND TRACK OF ANY OVERNIGHT MCS WILL DEPEND ON RELATIVE INFLUENCE OF ANY SFC-FORCED STORMS THAT DEVELOP IN ANOTHER 1-2 HOURS VERSUS MORE ELEVATED DEVELOPMENT LATER TONIGHT...FARTHER SE ACROSS SERN MO/WRN KY/WRN TN REGION WHERE 30-40 KT WLY LLJ IS PROGGED. MOST CONCENTRATED ACTIVITY SHOULD MOVE PARALLEL AND CLOSE TO INSTABILITY GRADIENT ASSOCIATED WITH FRONTAL ZONE IN SFC-850 MB LAYER. MAIN CONCERN WILL BE DAMAGING GUSTS...THOUGH LAPSE RATES AND DEEP-LAYER SHEAR PROFILES SUPPORTING SUPERCELLS SUGGEST HAIL THREAT CONTINUES AS WELL. ..EDWARDS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 06:08:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 02:08:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200605 SWODY1 SPC AC 200603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT SAT MAY 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN KS TO COASTAL CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF WI... ...SYNOPSIS... SYNOPTIC PATTERN WILL CONTINUE TO FEATURE WRN CONUS RIDGE AND ERN TROUGH. STRONG SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN MB -- IS FCST TO AMPLIFY AS IT MOVES SEWD TOWARD MEAN TROUGH POSITION. THIS SHOULD RESULT IN SMALL...CLOSED...TIGHTLY DEFINED...MIDDLE-UPPER LEVEL LOW MOVING SEWD ACROSS LS AND LH THROUGH PERIOD. ASSOCIATED SFC COLD FRONT -- NOW PASSING SRN TIP OF LAKE MANITOBA AND MOVING SWWD ACROSS SRN SASK -- IS FCST BY 21/00Z TO EXTEND FROM SSM AREA SWWD ACROSS IL/WI BORDER REGION...THEN WWD ACROSS IA AND SRN SD...BECOMING QUASISTATIONARY OVER SERN-N-CENTRAL MT. FARTHER S...PERSISTENT/QUASISTATIONARY FRONTAL ZONE WILL EXTEND FROM CAROLINAS GENERALLY WWD ACROSS OZARKS TO SWRN KS/SERN CO. MEANWHILE...AS MID/UPPER LEVEL CYCLONE SLOWLY PIVOTS EWD OFFSHORE NRN CA/ORE...PERTURBATION NOW OVER CENTRAL/NRN CA WILL MOVE THROUGH MEAN RIDGE POSITION ACROSS NRN ROCKIES. ...SERN KS TO TN VALLEY... STRONG CAPPING SHOULD PRECLUDE DEVELOPMENT OVER MOST OR ALL OF WARM SECTOR S OF FRONT...WITH POSSIBLE EXCEPTION OF INTENSELY HEATED/MIXED BUT RELATIVELY DRY AIR MASS OVER SRN HIGH PLAINS. LARGEST PROBABILITIES FOR SVR WILL BE WITH LATE AFTERNOON THROUGH EVENING DEVELOPMENT ALONG AND N OF SFC FRONT FROM SERN KS THROUGH TN VALLEY REGION...MOVING SEWD THROUGH OVERNIGHT HOURS. RELATIVE TO AREAS FARTHER E...STEEPEST MIDLEVEL LAPSE RATES AND GREATEST CONDITIONAL POTENTIAL FOR LARGE HAIL WILL BE ACROSS THIS REGION...HOWEVER STRONGER CINH MAY LIMIT CONVECTIVE COVERAGE. LOW LEVEL VERTICAL SHEAR AND HODOGRAPH SIZE WILL BE MAXIMIZED INVOF FRONT WHERE SFC WINDS SHOULD BE WEAK AND BACKED DIRECTIONALLY...COMPARED TO WARM SECTOR. 0-3 KM SRH 200-500 J/KG ARE POSSIBLE ALONG AND WITHIN 50-100 NM N OF FRONT...WHERE EFFECTIVE LIFTED PARCELS STILL ARE ROOTED AT SFC IN FCST SOUNDINGS VALID LATE AFTERNOON/EVENING. THEREAFTER...ACTIVITY SHOULD BE MORE ELEVATED BUT ALSO GREATER IN COVERAGE...WITH LARGE HAIL AND OCCASIONAL DAMAGING GUSTS POSSIBLE. ...SRN APPALACHIANS TO COASTAL CAROLINAS... TWO ROUNDS OF SEVERE POTENTIAL POSSIBLE OVER THIS REGION...MORNING THEN AFTERNOON. SHORT PERIOD OF FAVORABLE SFC HEATING IS POSSIBLE AFTER 12Z...AHEAD OF CONVECTIVE COMPLEX NOW TAKING SHAPE OVER KY...NERN TN AMD FAR SWRN VA. GUSTS/HAIL NEAR SVR LEVELS ARE POSSIBLE WITH THIS ACTIVITY BEFORE IT MOVES OFFSHORE...LEAVING BEHIND REINFORCED/DISPLACED FRONTAL ZONE ACROSS PORTIONS SRN NC AND SC...WNWWD ACROSS NRN GA. THIS BOUNDARY AND ASSOCIATED INSTABILITY GRADIENT SHOULD SERVE AS PRIMARY FOCUS FOR SUBSEQUENT CONVECTIVE DEVELOPMENT/MOTION. AIR MASS RECOVERY IS EXPECTED ALONG BOUNDARY THROUGH LATE MORNING INTO LATE AFTERNOON...WITH ADDITIONAL DEVELOPMENT POSSIBLE AS SFC DIABATICALLY WARMS. WELL-MIXED BOUNDARY LAYERS ARE EXPECTED WITH DEW POINT DEPRESSIONS AROUND 30 DEG F...LEADING TO INVERTED-V THERMODYNAMIC PROFILES BELOW LCL AND SUPPORTING MAINTENANCE TO SFC OF ANY HAIL OR STRONG-SEVERE GUSTS GENERATED ALOFT. DEEP-LAYER VERTICAL SHEAR PROFILES WILL SUPPORT BOTH SUPERCELLULAR AND BOW MODES FOR CONVECTION. ...MT... SCATTERED TSTMS ARE EXPECTED TO DEVELOP OVER HIGHER TERRAIN OF WRN MT DURING DAY...MOVING EWD ACROSS HIGH PLAINS AND POSSIBLY CONGEALING INTO ORGANIZED LINE/CLUSTER OF TSTMS. DAMAGING WIND SHOULD BE MAIN THREAT WITH OCCASIONAL HAIL ALSO PSBL...AS ACTIVITY MOVES INTO DEEPLY HEATED/MIXED AIR MASS WITH STEEP LOW-MIDLEVEL LAPSE RATES ALONG AND W OF SFC FRONT. APCHG SHORTWAVE TROUGH SHOULD ENHANCE CONVECTIVE ENVIRONMENT THROUGH COMBINATION OF INCREASING LARGE SCALE ASCENT/COOLING ALOFT AND LEE-SIDE ISALLOBARIC/ISALLOHYPSIC FORCING IN LOW LEVELS ACROSS MT. LATTER WILL HELP TO MAINTAIN BACKED/ENHANCED SFC WINDS INVOF BAROCLINIC ZONE...AS WELL AS LOW LEVEL WAA AFTER DARK THAT MAY COMBINE WITH FRONTAL LIFT TO SUSTAIN SOME CONVECTION INTO EVENING OR EARLY OVERNIGHT HOURS AS FAR E AS WRN DAKOTAS/NERN WY. ...WI... CONDITIONAL SVR RISK EXISTS OVER THIS REGION...WITH ONLY MINOR ADJUSTMENTS IN INFLOW-LAYER DEW POINTS NEEDED TO SHIFT CONVECTIVE POTENTIAL FROM BAND OF WEAK SHOWERS TO SEVERE SQUALL LINE. STRONG DEEP-LAYER FORCING AND WEAK CINH SHOULD COUNTERACT WEAK MOISTURE ENOUGH TO RESULT IN POTENTIAL FOR FAST MOVING CONVECTION THIS AFTERNOON...WITH THREAT FOR HAIL AND DAMAGING GUSTS. AS SHORTWAVE TROUGH DIGS SEWD TOWARD LS...VERY STRONG LARGE SCALE DPVA/ASCENT WILL BE CONCENTRATED JUST TO ITS SE. MUCH OF THIS REGIME WILL OCCUR BENEATH LEFT EXIT REGION OF STRENGTHENING AND CYCLONICALLY CURVED...115-130 KT JET MAX AT 250 MB...AND ALSO...INVOF VIGOROUS LOW LEVEL FRONTOGENETIC FORCING. ALTHOUGH BOUNDARY LAYER MOISTURE WILL BE MRGL WITH SFC DEW POINTS 40S TO LOW 50S F...SFC HEATING COMBINED WITH COOLING ALOFT SHOULD CONTRIBUTE TO DEEP ENOUGH BUOYANCY PROFILE FOR DEEP CONVECTION. SVR THREAT WILL DIMINISH EWD THIS EVENING ACROSS LM AND LOWER MI WHERE LOW LEVEL AIR MASS SHOULD BE MORE STABLE. ..EDWARDS/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 06:23:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 02:23:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200620 SWODY1 SPC AC 200618 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0118 AM CDT SAT MAY 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN KS TO COASTAL CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF WI... ...SYNOPSIS... SYNOPTIC PATTERN WILL CONTINUE TO FEATURE WRN CONUS RIDGE AND ERN TROUGH. STRONG SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER NRN MB -- IS FCST TO AMPLIFY AS IT MOVES SEWD TOWARD MEAN TROUGH POSITION. THIS SHOULD RESULT IN SMALL...CLOSED...TIGHTLY DEFINED...MIDDLE-UPPER LEVEL LOW MOVING SEWD ACROSS LS AND LH THROUGH PERIOD. ASSOCIATED SFC COLD FRONT -- NOW PASSING SRN TIP OF LAKE MANITOBA AND MOVING SWWD ACROSS SRN SASK -- IS FCST BY 21/00Z TO EXTEND FROM SSM AREA SWWD ACROSS IL/WI BORDER REGION...THEN WWD ACROSS IA AND SRN SD...BECOMING QUASISTATIONARY OVER SERN-N-CENTRAL MT. FARTHER S...PERSISTENT/QUASISTATIONARY FRONTAL ZONE WILL EXTEND FROM CAROLINAS GENERALLY WWD ACROSS OZARKS TO SWRN KS/SERN CO. MEANWHILE...AS MID/UPPER LEVEL CYCLONE SLOWLY PIVOTS EWD OFFSHORE NRN CA/ORE...PERTURBATION NOW OVER CENTRAL/NRN CA WILL MOVE THROUGH MEAN RIDGE POSITION ACROSS NRN ROCKIES. ...SERN KS TO TN VALLEY... STRONG CAPPING SHOULD PRECLUDE DEVELOPMENT OVER MOST OR ALL OF WARM SECTOR S OF FRONT...WITH POSSIBLE EXCEPTION OF INTENSELY HEATED/MIXED BUT RELATIVELY DRY AIR MASS OVER SRN HIGH PLAINS. LARGEST PROBABILITIES FOR SVR WILL BE WITH LATE AFTERNOON THROUGH EVENING DEVELOPMENT ALONG AND N OF SFC FRONT FROM SERN KS THROUGH TN VALLEY REGION...MOVING SEWD THROUGH OVERNIGHT HOURS. RELATIVE TO AREAS FARTHER E...STEEPEST MIDLEVEL LAPSE RATES AND GREATEST CONDITIONAL POTENTIAL FOR LARGE HAIL WILL BE ACROSS THIS REGION...HOWEVER STRONGER CINH MAY LIMIT CONVECTIVE COVERAGE. LOW LEVEL VERTICAL SHEAR AND HODOGRAPH SIZE WILL BE MAXIMIZED INVOF FRONT WHERE SFC WINDS SHOULD BE WEAK AND BACKED DIRECTIONALLY...COMPARED TO WARM SECTOR. 0-3 KM SRH 200-500 J/KG ARE POSSIBLE ALONG AND WITHIN 50-100 NM N OF FRONT...WHERE EFFECTIVE LIFTED PARCELS STILL ARE ROOTED AT SFC IN FCST SOUNDINGS VALID LATE AFTERNOON/EVENING. THEREAFTER...ACTIVITY SHOULD BE MORE ELEVATED BUT ALSO GREATER IN COVERAGE...WITH LARGE HAIL AND OCCASIONAL DAMAGING GUSTS POSSIBLE. ...SRN APPALACHIANS TO COASTAL CAROLINAS... TWO ROUNDS OF SEVERE POTENTIAL POSSIBLE OVER THIS REGION...MORNING THEN AFTERNOON. SHORT PERIOD OF FAVORABLE SFC HEATING IS POSSIBLE AFTER 12Z...AHEAD OF CONVECTIVE COMPLEX NOW TAKING SHAPE OVER KY...NERN TN AMD FAR SWRN VA. GUSTS/HAIL NEAR SVR LEVELS ARE POSSIBLE WITH THIS ACTIVITY BEFORE IT MOVES OFFSHORE...LEAVING BEHIND REINFORCED/DISPLACED FRONTAL ZONE ACROSS PORTIONS SRN NC AND SC...WNWWD ACROSS NRN GA. THIS BOUNDARY AND ASSOCIATED INSTABILITY GRADIENT SHOULD SERVE AS PRIMARY FOCUS FOR SUBSEQUENT CONVECTIVE DEVELOPMENT/MOTION. AIR MASS RECOVERY IS EXPECTED ALONG BOUNDARY THROUGH LATE MORNING INTO LATE AFTERNOON...WITH ADDITIONAL DEVELOPMENT POSSIBLE AS SFC DIABATICALLY WARMS. WELL-MIXED BOUNDARY LAYERS ARE EXPECTED WITH DEW POINT DEPRESSIONS AROUND 30 DEG F...LEADING TO INVERTED-V THERMODYNAMIC PROFILES BELOW LCL AND SUPPORTING MAINTENANCE TO SFC OF ANY HAIL OR STRONG-SEVERE GUSTS GENERATED ALOFT. DEEP-LAYER VERTICAL SHEAR PROFILES WILL SUPPORT BOTH SUPERCELLULAR AND BOW MODES FOR CONVECTION. ...MT... SCATTERED TSTMS ARE EXPECTED TO DEVELOP OVER HIGHER TERRAIN OF WRN MT DURING DAY...MOVING EWD ACROSS HIGH PLAINS AND POSSIBLY CONGEALING INTO ORGANIZED LINE/CLUSTER OF TSTMS. DAMAGING WIND SHOULD BE MAIN THREAT WITH OCCASIONAL HAIL ALSO PSBL...AS ACTIVITY MOVES INTO DEEPLY HEATED/MIXED AIR MASS WITH STEEP LOW-MIDLEVEL LAPSE RATES ALONG AND W OF SFC FRONT. APCHG SHORTWAVE TROUGH SHOULD ENHANCE CONVECTIVE ENVIRONMENT THROUGH COMBINATION OF INCREASING LARGE SCALE ASCENT/COOLING ALOFT AND LEE-SIDE ISALLOBARIC/ISALLOHYPSIC FORCING IN LOW LEVELS ACROSS MT. LATTER WILL HELP TO MAINTAIN BACKED/ENHANCED SFC WINDS INVOF BAROCLINIC ZONE...AS WELL AS LOW LEVEL WAA AFTER DARK THAT MAY COMBINE WITH FRONTAL LIFT TO SUSTAIN SOME CONVECTION INTO EVENING OR EARLY OVERNIGHT HOURS AS FAR E AS WRN DAKOTAS/NERN WY. ...WI... CONDITIONAL SVR RISK EXISTS OVER THIS REGION...WITH ONLY MINOR ADJUSTMENTS IN INFLOW-LAYER DEW POINTS NEEDED TO SHIFT CONVECTIVE POTENTIAL FROM BAND OF WEAK SHOWERS TO SEVERE SQUALL LINE. STRONG DEEP-LAYER FORCING AND WEAK CINH SHOULD COUNTERACT WEAK MOISTURE ENOUGH TO RESULT IN POTENTIAL FOR FAST MOVING CONVECTION THIS AFTERNOON...WITH THREAT FOR HAIL AND DAMAGING GUSTS. AS SHORTWAVE TROUGH DIGS SEWD TOWARD LS...VERY STRONG LARGE SCALE DPVA/ASCENT WILL BE CONCENTRATED JUST TO ITS SE. MUCH OF THIS REGIME WILL OCCUR BENEATH LEFT EXIT REGION OF STRENGTHENING AND CYCLONICALLY CURVED...115-130 KT JET MAX AT 250 MB...AND ALSO...INVOF VIGOROUS LOW LEVEL FRONTOGENETIC FORCING. ALTHOUGH BOUNDARY LAYER MOISTURE WILL BE MRGL WITH SFC DEW POINTS 40S TO LOW 50S F...SFC HEATING COMBINED WITH COOLING ALOFT SHOULD CONTRIBUTE TO DEEP ENOUGH BUOYANCY PROFILE FOR DEEP CONVECTION. SVR THREAT WILL DIMINISH EWD THIS EVENING ACROSS LM AND LOWER MI WHERE LOW LEVEL AIR MASS SHOULD BE MORE STABLE. ..EDWARDS/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 12:46:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 08:46:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201243 SWODY1 SPC AC 201242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT SAT MAY 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SE KS/THE OZARKS TO THE TN VLY...N GA...SC... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MT... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF WI AND MI... ...SYNOPSIS... AMPLIFIED PATTERN WILL PREVAIL AGAIN TODAY ACROSS THE CONUS. THE MAIN LARGE SCALE FEATURES WILL CONTINUE TO BE RIDGE ALONG THE RCKYS... BROAD TROUGH OVER ONTARIO/QUEBEC...AND MORE ELONGATED TROUGH OFF THE W CST. SEVERAL SHORTWAVE IMPULSES LIKELY WILL MODULATE TSTM DEVELOPMENT TODAY. THE FIRST OF THESE...NOW OVER ERN ORE...SHOULD CONTINUE NNE INTO SE AB BY THIS EVENING. FARTHER DOWNSTREAM IN SAME BAND OF FLOW...SATELLITE AND RUC ANALYSES DEPICT A SERIES OF WEAKER DISTURBANCES SHEARING SEWD FROM THE DAKOTAS THROUGH THE LWR MO VLY INTO TN AND THE CAROLINAS. IN THE NRN STREAM...A MUCH STRONGER IMPULSE NOW IN FAR WRN ONTARIO SHOULD REACH LK SUPERIOR/UPR MI BY TONIGHT...AND LK HURON EARLY SUNDAY. ...SE KS/OZARKS INTO TN/N GA/SC... WEAK FRONT NOW IN PLACE FROM SRN KS/SRN MO INTO MIDDLE TN AND SRN NC SHOULD REMAIN MORE OR LESS STATIONARY OR SETTLE JUST SLIGHTLY S TODAY. THE BOUNDARY LIKELY WILL SERVE AS A FOCUS FOR DIURNAL STORM DEVELOPMENT...ESPECIALLY FROM N GA WNW INTO NRN AL AND MIDDLE/WRN TN...WHERE HEATING SHOULD BE STRONGEST AND CINH RELATIVELY WEAK. TRUE/DEEPLY MIXED BOUNDARY LAYER DEWPOINTS SHOULD REMAIN IN THE UPR 50S TO LOW 60S. BUT GIVEN STRONG HEATING AND STEEP MID LEVEL LAPSE RATES ON SWRN FRINGE OF GRT LKS TROUGH...AFTERNOON SBCAPE SHOULD RANGE FROM 1500-2000 J/KG. A BIT LATER IN THE DAY...STORMS MAY ALSO FORM WWD ALONG FRONT INTO NRN AR/SRN MO. 30 KT WNWLY MID LEVEL FLOW AND WEAK IMPULSES ALOFT SHOULD SUPPORT ORGANIZED STORMS/STORM CLUSTERS WITH HAIL AND HIGH WIND. WHILE A FEW ROTATING STORMS MAY OCCUR...FAIRLY LARGE TEMP-DEWPOINT SPREADS AND FOCUSED LOW LEVEL FORCING SUGGEST PREFERRED EVOLUTION TOWARD COLD-POOL DRIVEN CLUSTERS WITH BOWING SEGMENTS/HIGH WIND. FARTHER W/SW...SUBSTANTIAL CAP EXPECTED TO PROHIBIT WARM SECTOR DEVELOPMENT...EXCEPT PERHAPS FOR A BRIEF PERIOD LATE THIS AFTERNOON/EARLY THIS EVENING INVOF LEE TROUGH OVER WRN OK AND THE TX PANHANDLE. LATER TONIGHT/EARLY SUNDAY...ADDITIONAL STORMS MAY FORM IN WAA AREA ALONG AND N OF STALLED FRONT IN SE KS AND SRN/CNTRL MO. IT APPEARS THAT LLJ WILL STRENGTHEN AS A RESULT OF BOTH DIURNAL INFLUENCES...AND THE CONTINUED SE MOTION OF WRN ONTARIO DISTURBANCE. SUFFICIENT SHEAR/INSTABILITY MAY BE PRESENT FOR ELEVATED STORMS WITH HAIL AND POSSIBLY HIGH WIND. ...MT/NRN PLNS... SCATTERED TSTMS SHOULD FORM OVER THE MOUNTAINS OF WRN MT TODAY ...WITH MOVEMENT/DEVELOPMENT EXPECTED TO SPREAD E/NE INTO THE NRN HI PLAINS AS ORE UPR IMPULSE CONTINUES NNEWD. SUSTAINED FORCING FOR ASCENT AND MODERATE TEMP-DEWPOINT SPREADS SHOULD FAVOR EVOLUTION INTO A LINE/CLUSTER MODE WITH DAMAGING WIND AND MARGINALLY SEVERE HAIL. BACKED/SLIGHTLY UPSLOPE FLOW ALONG LEE TROUGH OVER THE CNTRL PART OF THE STATE SHOULD ENHANCE LOW LEVEL CONVERGENCE...AND FORWARD PROPAGATION OF STORMS INTO ERN MT BY MID TO LATE EVENING. LATER TONIGHT...WAA MAY INCREASE OVER THE WRN DAKOTAS ON BACK SIDE OF SURFACE RIDGE BUILDING SWD IN WAKE OF ONTARIO DISTURBANCE. ENHANCED FRONTAL UPLIFT AND LARGE SCALE ASCENT IN ENTRANCE REGION OF ASSOCIATED UPR LEVEL JET STREAK MAY SUSTAIN SOME OF THE STORMS INTO EARLY SUNDAY OVER THE WRN DAKOTAS/NE WY. ...WI/MI... LARGE SCALE FORCING FOR ASCENT WILL INCREASE SUBSTANTIALLY ACROSS THE UPR GRT LKS REGION TODAY AS POTENT WRN ONTARIO TROUGH DROPS SE TOWARD LK SUPERIOR. BOUNDARY LAYER MOISTURE WILL BE LIMITED... WITH AVERAGE SURFACE DEWPOINTS LIKELY REMAINING IN THE MID 40S ACROSS WI AND MI. BUT COINCIDENTAL ARRIVAL OF STRONG FRONTOGENETIC FORCING WITH DAYTIME HEATING/STEEPENING LOW LEVEL LAPSE RATES...AND STRENGTHENING OF MEAN WNWLY FLOW TO AOA 40 KTS...ALL SUGGEST POTENTIAL FOR A STRONGLY FORCED LINE OF LOW-TOPPED/ LOW-REFLECTIVITY STORMS WITH DAMAGING WIND. THIS ACTIVITY MAY REACH AS FAR S AS THE MKE/GRR/MBS AREAS BEFORE WEAKENING OVER SERN LWR MI LATER TONIGHT. ..CORFIDI/GRAMS.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 16:25:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 12:25:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201618 SWODY1 SPC AC 201616 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1116 AM CDT SAT MAY 20 2006 VALID 201630Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE OZARKS TO THE CAROLINA COAST... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE CENTRAL GREAT LAKES... ...MID SOUTH ACROSS SRN APPALACHIANS INTO THE COASTAL CAROLINAS... QUASI-STATIONARY FRONT EXTENDING FROM FAR SRN MO ESEWD INTO MIDDLE TN AND EWD INTO THE PIEDMONT OF NC/VA THIS MORNING WILL PROVIDE PRIMARY FOCUS FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON/EVENING. SURFACE OUTFLOW BOUNDARY ACROSS SERN SC INTO NRN GA MAY PROVIDE ADDITIONAL FOCUS. THOUGH MID/UPPER LEVEL PATTERN REMAINS MORE LIKE MID-SUMMER...WARM SECTOR MOISTURE IS NOT OVERLY IMPRESSIVE WITH SURFACE DEW POINTS IN THE LOWER TO MID 60S. LIMITED LARGE SCALE ASCENT AND RISING HEIGHTS AT H5 INDICATE DEVELOPMENT WILL BE DRIVEN BY HEATING TODAY. LACK OF LARGE SCALE FOCUS AND LIMITED LLJ DEVELOPMENT SUGGEST THUNDERSTORMS COULD INITIATE ANYWHERE ALONG THE FRONT/OUTFLOW BOUNDARY THIS AFTERNOON...WHERE POCKETS OF WEAK CINH DEVELOP. HOWEVER...SATELLITE IMAGERY AND RECENT CONVECTIVE TRENDS MAY SUPPORT WEAK IMPULSE NOW MOVING ESEWD ACROSS MIDDLE TN WHICH COULD FOCUS INITIAL DEVELOPMENT ACROSS THE SRN APPALACHIANS EARLY THIS AFTERNOON. MODELS ARE AGAIN FAR TOO MOIST NEAR THE SURFACE AND APPEAR TO BE OVER FORECASTING EXPECTED SBCAPE/MLCAPE TODAY. HOWEVER...MLCAPE MAY STILL APPROACH 2000 J/KG ACROSS THE UPPER SOUTH /SOUTH OF SURFACE BOUNDARY/ WHERE AFTERNOON TEMPS APPROACH/EXCEED 90F. MODEST WLY FLOW ALOFT WILL ALSO SUSTAIN 35-45 KT EFFECTIVE SHEAR...SUPPORTIVE OF SUPERCELLS AND ORGANIZATION INTO SMALL LINES/BOW ECHOES MOVING SEWD LATER TODAY AND THIS EVENING. STEEP SUB-CLOUD LAPSE RATES AND NEAR UNIDIRECTIONAL FLOW ALOFT WILL SUPPORT PRIMARY THREAT OF DAMAGING WINDS. THOUGH PRESENCE OF SURFACE BOUNDARY MAY ENHANCE LOW LEVEL SHEAR ENOUGH FOR A TORNADO OR TWO...WHILE MLCAPE AND STEEP LAPSE RATES ALSO SUPPORT LARGE HAIL. ...SRN HIGH PLAINS INTO THE OZARKS... BOUNDARY WILL REMAIN STALLED NEAR THE MO/AR BORDER INTO FAR SRN KS/NWRN OK TODAY...AS WEAK LOW CENTER PERSISTS ALONG TRIPLE POINT OF FRONT AND DRY LINE NEAR THE TX/OK PANHANDLES. STRONG HEATING AND INFLUX OF ASCENT AHEAD OF WEAK SHORTWAVE TROUGH NOW SHIFTING SEWD ACROSS NEB SHOULD SUPPORT A FEW THUNDERSTORMS NEAR THIS BOUNDARY LATER TODAY. WRN END OF FRONT ACROSS NRN EXTENT OF SRN PLAINS REMAINS UNDER MID LEVEL RIDGE AND ASSOCIATED WEAK MID LEVEL FLOW... SUGGESTING STORMS ACROSS THIS AREA WILL BE MORE PULSE IN NATURE WITH BRIEF DAMAGING WINDS/HAIL. STORMS WHICH CAN DEVELOP AHEAD OF WEAK MID LEVEL SYSTEM INTO SRN MO/FAR SERN KS WILL HAVE MODEST SHEAR AND LIKELY ORGANIZE INTO MULTICELL CLUSTERS/LINES WITH THREATS OF LARGE HAIL/DAMAGING WINDS LATE TODAY AND THIS EVENING. ...MT INTO FAR NERN WY... WELL DEFINED SHORTWAVE TROUGH NOW LIFTING ACROSS THE NRN INTERMOUNTAIN REGION WILL INCREASE MOIST CONVECTION ACROSS THE NRN ROCKIES TODAY...WHERE MODEST LAPSE RATES AND SURFACE DEW POINTS AROUND 50F WILL SUPPORT MARGINAL TO MODERATE INSTABILITY TODAY. ASSOCIATED 40-50 KT SWLY MID LEVEL SPEED MAX WILL ALSO INCREASE DEEP LAYER SHEAR ACROSS MUCH OF WRN/CENTRAL MT AND NRN WY THIS AFTERNOON...WHERE FORECAST SOUNDINGS YIELD SUFFICIENT DEEP LAYER SHEAR FOR A FEW SUPERCELLS AND ORGANIZED CLUSTERS/LINES. SURFACE COLD FRONT NOW MOVING SWD INTO THE NRN PLAINS HAS PUSHED WWD INTO ERN MT THIS MORNING AND MAY LIMIT EWD EXTENT OF ANY SEVERE THREAT LATER THIS EVENING. HOWEVER...ACTIVITY INCREASING ACROSS WRN MT INTO NRN WY WILL LIKELY BECOME SEVERE OVER LOWER ELEVATIONS GIVEN STRONG HEATING AND SHIFT ENEWD THROUGH THE EVENING. ...CENTRAL GREAT LAKES... SEVERE THREAT APPEARS CONDITIONAL ACROSS THIS REGION AS PRE-FRONTAL BOUNDARY LAYER MOISTURE AND MID LEVEL LAPSE RATES REMAIN WEAK THIS MORNING. HOWEVER...STRONG COLD FRONT ASSOCIATED WITH DEEPENING SHORTWAVE TROUGH NOW SHIFTING SSEWD INTO THE NRN GREAT LAKES WILL SUPPORT STRONG LARGE SCALE ASCENT ACROSS THE CENTRAL GREAT LAKES TODAY. MODELS CONTINUE TO INCREASE SURFACE DEW POINTS INTO THE LOWER 50S IMMEDIATELY AHEAD OF APPROACHING COLD FRONT. HOWEVER...LATEST OBSERVATIONAL DATA SUGGESTS THIS MAY BE OVERDONE AND CASTS SOME DOUBT AS TO WHETHER OR NOT SUFFICIENT INSTABILITY WILL DEVELOP FOR SURFACE-BASED CONVECTION ALONG THE FRONT. SHOULD THUNDERSTORMS FORM WITHIN NARROW AXIS OF MARGINAL INSTABILITY TODAY...VERY STRONG WINDS ALOFT AND INCREASING LARGE SCALE ASCENT COULD SUPPORT DAMAGING WINDS AS STEEP SUB-CLOUD LAPSE RATES DEVELOP FROM SURFACE TEMPERATURES APPROACHING 70F. ..EVANS/GUYER.. 05/20/2006  From swody1 at goshenarc.org Sat May 20 20:06:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 16:06:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 202002 SWODY1 SPC AC 202001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT SAT MAY 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF MT AND WY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID MS VALLEY...TN VALLEY AND CAROLINAS... ...CAROLINAS/TN VALLEY/OZARK PLATAEA... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BAND OF NORTHWEST FLOW ACROSS THE MID-MS AND TN VALLEYS. AT THE SFC...A NEARLY STATIONARY FRONT EXTENDS EWD ACROSS NRN TN INTO NC. SOUTH OF THE BOUNDARY...SFC DEWPOINTS ARE IN THE 60S F AND MODERATE INSTABILITY EXISTS. AN MCS IS CURRENTLY DEVELOPING ALONG THE NRN EDGE OF THE INSTABILITY AXIS AHEAD OF A SUBTLE SHORTWAVE TROUGH IN THE SRN APPALACHIAN MTNS. THIS STORM COMPLEX WILL CONTINUE TO EXPAND AND SPREAD ESEWD ACROSS NRN GA AND WRN SC LATE THIS AFTERNOON INTO THE EARLY EVENING. FORECAST SOUNDINGS LATE THIS AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ALONG THE FRONTAL BOUNDARY IN THE TN VALLEY AND CAROLINAS SUGGESTING SUPERCELLS WILL BE LIKELY ESPECIALLY EARLY IN THE DEVELOPMENT OF THE MCS. THE TORNADO THREAT SHOULD BE ENHANCED OVER NRN GA AND WRN SC WHERE THE LOW-LEVEL SHEAR ENVIRONMENT APPEARS MORE FAVORABLE DUE TO A 30-40 KT LOW-LEVEL JET. IN ADDITION...OBJECTIVE ANALYSIS SHOWS A PLUME OF STEEP MID-LEVEL LAPSE RATES EXTENDING EWD ACROSS MS...AL AND NRN GA SUGGESTING SUPERCELLS WITH VERY LARGE HAIL WILL ALSO BE POSSIBLE. AS THE MCS MATURES THIS EVENING...THE UNIDIRECTIONAL WIND ENVIRONMENT SUGGESTS THE WIND DAMAGE THREAT MAY ALSO BECOME ENHANCED. FURTHER WEST ACROSS THE OZARK PLATEAU...CONVECTIVE INITIATION WILL LIKELY HOLD OFF DUE TO A CAPPING INVERSION UNTIL THE LATE AFTERNOON AND/OR EARLY EVENING. FORECAST SOUNDINGS IN THIS AREA FOR EARLY THIS EVENING SHOW STEEP LAPSE RATES AND MODERATE VERTICAL SHEAR PROFILES SUGGESTING LARGE HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE. THE SEVERE THREAT MAY PERSIST THROUGH THE EVENING WITH ANY MCS CLUSTER THAN DEVELOPS AND MOVES ESEWD ACROSS THE REGION. ...MT/WY... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL RIDGE IN PLACE ACROSS THE ROCKIES WITH A SHORTWAVE TROUGH TOPPING THE RIDGE. AT THE SFC...A TROUGH CURRENTLY EXTENDS NNWD INTO NRN WY AND WCNTRL MT. SFC DEWPOINTS EAST OF THE SFC TROUGH RANGE FROM THE MID 40S TO MID 50S F WHERE POCKETS OF MODERATE INSTABILITY ARE PRESENT ACCORDING TO OBJECTIVE ANALYSIS. A LINE OF STRONG THUNDERSTORMS IS ORGANIZING IN THE FOOTHILLS AND WILL INCREASE IN COVERAGE...MOVING INTO THE PLAINS THIS AFTERNOON. FORECAST SOUNDINGS THIS AFTERNOON SHOW MODERATE VERTICAL SHEAR PROFILES SUGGESTING ISOLATED SUPERCELLS WITH LARGE HAIL WILL BE POSSIBLE WHERE THE INSTABILITY IS LOCALLY MAXIMIZED. IF LINEAR MCS DEVELOPMENT CONTINUES...BOW ECHOES EMBEDDED WITH THE LINE WOULD ALSO BE LIKELY WITH A THREAT FOR WIND DAMAGE THROUGH EARLY EVENING. ...UPPER GREAT LAKES... WATER VAPOR IMAGERY CURRENTLY SHOWS A BROAD BAND OF NWLY FLOW ACROSS THE UPPER MIDWEST. AN 80 KT MID-LEVEL JET EMBEDDED IN THE FLOW IS PUNCHING SEWD ACROSS THE REGION WHICH IS ENHANCING VERTICAL SHEAR PROFILES. MODEL FORECASTS SHOW LINEAR CONVECTIVE DEVELOPMENT MOVING SEWD ACROSS THE REGION LATE THIS AFTERNOON. ALTHOUGH INSTABILITY IS WEAK...THE STRONG SHEAR ENVIRONMENT SUGGESTS A MARGINAL WIND DAMAGE AND/OR HAIL THREAT MAY EXIST WITH THIS CONVECTION FOR A FEW HOURS THIS AFTERNOON. ..BROYLES.. 05/20/2006  From swody1 at goshenarc.org Sun May 21 01:12:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 20 May 2006 21:12:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210109 SWODY1 SPC AC 210107 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0807 PM CDT SAT MAY 20 2006 VALID 210100Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS SE KS TO SC COAST... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS ERN MT...NERN WY...EXTREME WRN SD... ...SYNOPSIS... LARGE SCALE PATTERN CONTINUES TO FEATURE ERN CONUS MEAN TROUGH AND RIDGE FROM N-CENTRAL MEX ACROSS CENTRAL ROCKIES TO CANADIAN NW TERRITORIES. EMBEDDED IN PREVAILING NW FLOW...WEAK SHORTWAVE TROUGH IS EVIDENT IN MOISTURE CHANNEL IMAGERY AND VWP/PROFILER DATA OVER PORTIONS IL/MO. THIS FEATURE IS FCST TO TURN ESEWD THEN EWD ACROSS SRN APPALACHIANS AS IT MOVES THROUGH MEAN TROUGH POSITION...REACHING INVOF TIDEWATER REGION OF ATLANTIC COAST BY END OF PERIOD. AT SFC...QUASISTATIONARY BAROCLINIC ZONE -- MODULATED/SHIFTED ON MESOBETA SCALE BY CONVECTIVE OUTFLOWS TO ITS S -- IS ANALYZED FROM ERN VA WSWWD ACROSS TN...AR/MO BORDER REGION AND KS/OK BORDER REGION...BECOMING DIFFUSE WWD INTO S-CENTRAL ROCKIES. SECONDARY/REINFORCING FRONTAL SURGE -- ASSOCIATED WITH GREAT LAKES MID/UPPER TROUGH -- IS ANALYZED FROM LH WSWWD ACROSS NRN/WRN LOWER MI...NRN IA...WRN SD...E-CENTRAL MT. THIS FRONT SHOULD CONTINUE TO MOVE SEWD THROUGH REMAINDER LM/LH AND ADJOINING PARTS MI/WI...SWD ACROSS N-CENTRAL PLAINS AND SLOWLY WWD OVER NRN HIGH PLAINS. ...OZARK REGION TO CAROLINAS COAST... REF SPC WWS 368...370...371 AND RELATED MESOSCALE DISCUSSIONS FOR NOWCAST SCENARIO ACROSS THIS REGION. LARGE SCALE ASCENT AHEAD OF MIDLEVEL PERTURBATION...30-40 KT LLJ AND NARROW PLUME OF AT LEAST MRGL 925-850 MB LAYER MOISTURE WILL SUPPORT CLUSTERS OF TSTMS THROUGH MUCH OF THIS SWATH...WITH EPISODIC POTENTIAL FOR SVR HAIL AND DAMAGING GUSTS. LATE THIS EVENING INTO OVERNIGHT HOURS...CORRIDOR OF MOST FAVORABLE SEVERE POTENTIAL WILL BE NARROWED FROM N-S AND RENDERED MORE ELEVATED/MRGL. THIS WILL OCCUR AS 1. COLLECTIVE CONVECTIVE OUTFLOWS EFFECTIVELY SHUNT FRONTAL ZONE SWD...AND AS 2. POCKETS OF RELATIVELY DRY AND WELL MIXED BOUNDARY LAYER AIR -- NOW ANALYZED IN SFC CHARTS FROM CENTRAL MS TO CENTRAL GA -- ADVECT ENEWD WHILE DIABATICALLY COOLING AND DESTABILIZING. ...NRN HIGH PLAINS... AREA OF OPTIMAL SEVERE POTENTIAL IS SHRINKING AS PRIMARY CENTRAL MT MCS MOVES INTO SUBSTANTIALLY MORE STABLE AIR MASS ALONG AND E OF SFC FRONT...REPRESENTED BY 00Z GGW RAOB. REF WW 367 AND LATEST ACCOMPANYING MESOSCALE DISCUSSION FOR MORE DETAILS. OVERALL SEVERE POTENTIAL SHOULD DIMINISH AFTER DARK AS BOUNDARY LAYER COOLS BETWEEN FRONT AND CONVECTIVE FORCING BOUNDARIES. WAA AND WEAK MOIST ADVECTION -- ASSOCIATED WITH SELY-SSELY LLJ OF 30-40 KT -- MAY HELP TO SUSTAIN SOME OF THIS CONVECTION AFTER 6Z...WITH HAIL/GUSTS TO NEAR SVR LEVELS POSSIBLE. ..EDWARDS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 06:05:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 02:05:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210601 SWODY1 SPC AC 210559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT SUN MAY 21 2006 VALID 211200Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS ERN ORE...SERN WA...WRN ID... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS MT...EXTREME N-CENTRAL WY... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL KS TO WRN KY AND NWRN TN... ...SYNOPSIS... STABLE LARGE SCALE PATTERN WITH MEAN WRN RIDGE AND ERN TROUGH WILL CONTINUE...BUT WITH SOME IMPORTANT SHORTWAVE CHANGES DURING DAY-1. STRONG MID/UPPER LEVEL LOW INITIALLY OVER UPPER GREAT LAKES IS FCST TO TURN EWD THEN NEWD PAST MEAN TROUGH POSITION...THEN PRONOUNCED MID/UPPER LEVEL LOW -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY INVOF 35N130W...HAS BEGUN SLGT SEWD TURN AND SHOULD CONTINUE THIS TREND THROUGH PERIOD. LOW SHOULD BE LOCATED JUST OFFSHORE SRN CA/NRN BAJA BY 22/12Z...WITH ASSOCIATED LOW LEVEL BAROCLINIC ZONE INCREASING CONVECTIVE POTENTIAL ACROSS MUCH OF CENTRAL/SRN CA WITH TIME THROUGH DAY-1. HEIGHTS ALSO SHOULD FALL ACROSS PACIFIC NW MID-LATE PERIOD IN RESPONSE TO SPEED MAX NOW DIGGING SEWD ACROSS GULF OF AK. AT SFC...RAGGED BAROCLINIC ZONE WITH MESOBETA SCALE OUTFLOW ENHANCEMENTS WILL PERSIST FROM SC COAST WNWWD OVER OZARKS REGION AND SRN KS...BECOMING DIFFUSE FARTHER WNW INTO ERN CO. SECONDARY/REINFORCING FRONT NOW EVIDENT FROM ERN MT SEWD ACROSS NERN NEB SHOULD BECOME NEARLY STATIONARY OVER NRN HIGH PLAINS THROUGH MOST OF PERIOD...AND NEARLY COLOCATED WITH LEE TROUGH IN MT. ...INTERIOR NWRN CONUS... AS HEIGHTS FALL AND GRADIENTS TIGHTEN ACROSS THIS REGION...DEEP-LAYER VERTICAL SHEAR PROFILES ARE EXPECTED TO BECOME FAVORABLE FOR SEVERE DURING AFTERNOON IN TANDEM WITH PEAK SFC WARMTH. NEARLY STRAIGHT LOW-MIDDLE LEVEL HODOGRAPHS ARE PROGGED...RESULTING FROM LOW LEVEL FLOW WITH WEAK SPEEDS BUT PRONOUNCED VEERING THAT TRANSITIONS TO 50-60 KT SSWLY FLOW IN 400-600 MB LAYER...YIELDING ABOUT 50 KT EFFECTIVE SHEAR. MODIFIED ETA/WRF SOUNDINGS SUGGEST SFC TEMPS LOW 70S AND DEW POINTS LOW 50S F WILL RESULT IN WELL MIXED BOUNDARY LAYERS WITH LITTLE OR NO CINH...INVERTED-V THERMODYNAMIC PROFILES IN SUBCLOUD LAYER...AND 600-1200 J/KG MLCAPE. THESE FACTORS SUPPORT BOTH BOW AND SUPERCELL POTENTIAL...WITH DAMAGING GUSTS AND LARGE HAIL. MAIN CONCERN FOR CONVECTIVE COVERAGE AND ORGANIZATION IS STRENGTH OF AFTERNOON HEATING GIVEN POTENTIAL FOR MID/HIGH LEVEL CLOUDS STREAMING NWD FROM VICINITY OF LOW APCHG CA. SVR THREAT SHOULD DIMINISH ONCE EVENING COOLING BEGINS TO STABILIZE PRECONVECTIVE BOUNDARY LAYER...AND AS ACTIVITY MOVES INTO MORE STABLE AMBIENT AIR MASS FARTHER NE. ...MT... ANOTHER EPISODE OF STRONG-SEVERE TSTMS IS POSSIBLE DURING AFTERNOON INTO EARLY EVENING...RESULTING FROM ACTIVITY INITIATING INVOF HIGHER TERRAIN OF SRN/WRN MT MID-LATE AFTERNOON. TSTMS MAY ORGANIZE INTO ONE OR MORE OUTFLOW-DOMINANT BANDS OR CLUSTERS...FORWARD PROPAGATING WITH MAIN THREAT BEING DAMAGING WIND. ALTHOUGH HEIGHTS ARE EXPECTED TO RISE GRADUALLY THROUGHOUT PERIOD OVER THIS REGION AS MEAN RIDGE AMPLIFIES...STRONG SFC HEATING AND WEAKENING CINH SHOULD SUPPORT AFTERNOON TSTM DEVELOPMENT. FAVORABLE DEEP-LAYER SHEAR PROFILES ARE EXPECTED WITH 40-50 KT OVER NRN PORTION OUTLOOK AREA...TRENDING TO ABOUT 35 KT AND LESS S OF MT/WY BORDER. SVR POTENTIAL IS EXPECTED TO DIMINISH MARKEDLY DURING EVENING AS FOREGOING BOUNDARY LAYER DIABATICALLY COOLS...AND AS ACTIVITY MOVES INTO PROGRESSIVELY LESS BUOYANT AIR MASS E OF SFC FRONT. ...CENTRAL PLAINS TO SC COAST... AS GREAT LAKES UPPER LOW EJECTS...HEIGHTS ARE FCST TO RISE ACROSS MOST OF CENTRAL/SERN CONUS THROUGHOUT PERIOD. CORRESPONDING DECREASE IN HEIGHT GRADIENT ALOFT...AND RELATED WEAKENING OF BOTH LARGE SCALE SUPPORT AND DEEP-LAYER KINEMATIC FIELDS WITH TIME -- INDICATE MORE CONDITIONAL/DISORGANIZED SEVERE POTENTIAL THIS PERIOD OVER MOST OF THIS CORRIDOR. HOWEVER...WILL MAINTAIN MRGL THRESHOLD PROBABILITIES FOR CATEGORICAL SLGT RISK ACROSS SUBSET OF THIS CORRIDOR...FROM S-CENTRAL KS TO NWRN TN -- COMBINING 1. CONDITIONAL DIURNAL RISK OF WIND AND HAIL INVOF FRONT WITH 2. SOMEWHAT HIGHER CONFIDENCE BUT LOWER MAGNITUDE HAIL THREAT AFTER DARK N OF FRONT. VEERING WIND PROFILES WITH HEIGHT WILL CONTINUE DESPITE WEAKENING LOW-MIDLEVEL SPEEDS...SUPPORTING POTENTIAL FOR STORM ORGANIZATION WITH ANY ACTIVITY THAT DEVELOPS. MIDLEVEL LAPSE RATES ACROSS THIS REGION SHOULD REMAIN RELATIVELY STEEP -- 7.5-8.5 DEG C/KM -- IN SUPPORT OF FAVORABLE BUOYANCY. AFTERNOON MLCAPES ALONG FRONT...AND LATE EVENING ELEVATED MUCAPES FARTHER N...SHOULD BE ENHANCED BY LOW LEVEL MOIST AXIS WITH VALUES OF EACH AROUND 1000-1500 J/KG. ...CENTRAL HIGH PLAINS... WIDELY SCATTERED TSTMS IN LOOSELY ORGANIZED CLUSTERS MAY EVOLVE DURING LATE AFTERNOON AND EVENING ACROSS HIGH PLAINS FROM NERN WY TO ERN CO/WRN KS...SOME OF WHICH MAY PRODUCE GUSTS NEAR SEVERE LIMITS. AFTERNOON INITIATION WILL BE AIDED BY ELY/UPSLOPE COMPONENT OF SFC FLOW...AMIDST WEAK CINH CAUSED BY AT LEAST MRGL SFC MOISTURE AND STRONG HEATING OF ELEVATED TERRAIN. VERY WEAK LOW/MIDLEVEL FLOWS AND DEEP-LAYER SHEAR PROFILES ARE EXPECTED TO LIMIT POTENTIAL FOR SUSTAINED/WELL-ORGANIZED SVR...THOUGH DEEPLY MIXED BOUNDARY LAYERS WILL SUPPORT STRONG/POSSIBLY SVR OUTFLOW WINDS IN SOME LOCALES. ..EDWARDS/GRAMS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 12:56:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 08:56:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211253 SWODY1 SPC AC 211251 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 AM CDT SUN MAY 21 2006 VALID 211300Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SE KS INTO THE TN VLY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CNTRL HI PLNS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER INTERIOR PARTS OF THE PAC NW/MT... ...SYNOPSIS... RCKYS RIDGE EXPECTED TO AMPLIFY SLIGHTLY AS IT SHIFTS E INTO THE HI PLNS BETWEEN NOW AND MONDAY...LARGELY IN RESPONSE TO DEEPENING OF UPR LOW W OF BC. DEEPENING OF BC LOW SHOULD DRIVE UPR SYSTEM NOW OFF THE CNTRL CA CST SE TOWARD SAN DIEGO BY EARLY MONDAY...AND MAINTAIN DEEP SSWLY FLOW OVER THE FAR WEST. AT THE SAME TIME... SYSTEM THAT CROSSED THE UPR GRT LKS YESTERDAY WILL REINFORCE EXISTING TROUGH OVER THE NORTHEAST. ASSOCIATED COLD FRONT SHOULD CONTINUE SW INTO THE LWR MO/MID MS VLYS...AND S/SE ACROSS THE OH VLY AND MID ATLANTIC STATES. THE FRONT SHOULD EVENTUALLY MERGE WITH WEAKER ONE NOW EXTENDING FROM CNTRL KS ESE INTO THE TN VLY. ...KS/MO E/SE INTO TN VLY... WHILE UPR RIDGE WILL AMPLIFY SOMEWHAT OVER THE HI PLNS...GLANCING INFLUENCE OF GRT LKS SPEED MAX WILL MAINTAIN 25-30 KT MID LEVEL WNWLY FLOW ABOVE WEAK FRONT STALLED FROM KS/SRN MO ESE INTO THE TN VLY. MODERATE SURFACE HEATING...RELATIVELY STEEP MID LEVEL LAPSE RATES /7.5-8.5 DEG C PER KM/...FAIRLY MOIST AIR /WARM SECTOR DEWPOINTS IN THE LOW 60S/ AND FRONTAL CONVERGENCE TOGETHER SHOULD SUPPORT RENEWED STORM DEVELOPMENT ALONG THE BOUNDARY BY MID TO LATE AFTERNOON. THIS POTENTIAL APPEARS MOST LIKELY FROM SE KS INTO SW MO...WHERE A RELATIVE MAXIMUM IN LOW LEVEL INFLOW SHOULD EXIST INVOF OUTFLOW BOUNDARIES LEFT BY OVERNIGHT STORMS. MORE WIDELY SCATTERED/ LESS SUSTAINED ACTIVITY SHOULD PREVAIL FARTHER E/SE ALONG FRONT... FROM THE TN VLY TO THE SC CST. 30-35 KT DEEP NWLY SHEAR SHOULD BE SUFFICIENT FOR ORGANIZED/ SUSTAINED STORMS AND POSSIBLE SUPERCELLS WITH HAIL/HIGH WIND... ESPECIALLY GIVEN ENHANCED DIRECTIONAL COMPONENT INVOF FRONT. ADDITIONAL STORMS MAY FORM N OF BOUNDARY IN MO TONIGHT/EARLY MONDAY AS NOCTURNAL STRENGTHENING/VEERING OF LLJ...AND AFOREMENTIONED MERGING OF FRONTS...ENHANCE WAA ACROSS THE REGION. ...CNTRL HI PLNS... WIDELY SCATTERED TSTMS THAT EVOLVE INTO LOOSELY ORGANIZED CLUSTERS WITH A THREAT FOR HIGH WIND MAY FORM LATE THIS AFTERNOON/EARLY TONIGHT FROM NE CO INTO ERN WY/THE NEB PANHANDLE. INITIATION WILL BE SUPPORTED BY ELY/UPSLOPE SFC FLOW...DUE LARGELY TO STRONG HEATING OF ELEVATED TERRAIN. SLOWLY RISING HEIGHTS ALOFT AND WEAK LOW LEVEL WINDS SHOULD LIMIT OVERALL STORM STRENGTH. BUT 25+ KT MID LEVEL WNW FLOW AND VERY DEEPLY MIXED BOUNDARY LAYER ENVIRONMENT WILL SUPPORT STRONG STORM OUTFLOW AND UPSCALE GROWTH INTO CLUSTERS. ...INTERIOR PAC NW INTO MT... WATER VAPOR IMAGERY AND RUC 500 MB VORT ANALYSIS SHOW A WEAK IMPULSE OVER NE NV THAT SHOULD CONTINUE NNE ACROSS SRN/ERN ID THROUGH MIDDAY...AND INTO N CNTRL MT BY THIS LATE AFTERNOON. THIS FEATURE...COUPLED WITH SURFACE HEATING...OROGRAPHIC ASCENT AND WEAKLY CONVERGENT LOW LEVEL FLOW...MAY SUPPORT ANOTHER ROUND OF STRONG TO SEVERE STORMS IN CNTRL MT. LARGE TEMP-DEWPOINT SPREADS AND MODERATE UNIDIRECTIONAL CLOUD LAYER FLOW SUGGEST MAIN SEVERE THREATS WILL BE WIND AND MARGINALLY SEVERE HAIL. FARTHER W...A CONDITIONAL RISK FOR STRONG/POSSIBLY SEVERE DIURNAL STORMS WILL EXIST IN MORE STRONGLY SHEARED UNIDIRECTIONAL WIND ENVIRONMENT OVER ERN/NRN ORE AND SE WA/WRN ID. MODIFIED ETA/WRF SOUNDINGS WITH SFC TEMPS IN THE LOW 70S AND DEWPOINTS IN THE LOW 50S F YIELD WELL-MIXED BOUNDARY LAYERS WITH LITTLE OR NO CINH...INVERTED-VEE SUBCLOUD LAYER THERMODYNAMIC PROFILES...AND ABOUT 1000 J/KG MLCAPE. COUPLED WITH 40+ KT DEEP SLY FLOW ON ERN FRINGE OF OFFSHORE TROUGH...SUCH A SETUP WOULD SUPPORT SUSTAINED STORMS AND POSSIBLE SUPERCELLS. ASSOCIATED EMBEDDED BOWS WOULD HAVE THE POTENTIAL FOR BOTH HIGH WIND AND HAIL. A MAJOR UNCERTAINTY REMAINS...HOWEVER...REGARDING CONVECTIVE COVERAGE AS LARGE SCALE FORCING FOR ASCENT SHOULD REMAIN WEAK...AND MID/HIGH LEVEL CLOUDS WILL LIMIT LOW LEVEL HEATING. SEEMS PRUDENT ATTM TO MAINTAIN A LOW PROBABILITY RISK FOR SEVERE IN THIS AREA UNTIL IT IS CLEAR THAT STORMS WILL INDEED NOT FORM. ..CORFIDI/GRAMS.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 16:29:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 12:29:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211614 SWODY1 SPC AC 211613 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1113 AM CDT SUN MAY 21 2006 VALID 211630Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN KS/NERN OK TO THE SC COAST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL HIGH PLAINS... ...TN VALLEY TO THE SOUTHEASTERN U.S. COAST... SURFACE FRONT REMAINS IN PLACE FROM THE SERN NC COAST WNWWD INTO THE MO BOOTHEEL REGION TODAY...WITH MODERATE TO STRONG WNWLY FLOW ALOFT PERSISTING ALONG THIS BOUNDARY. AIR MASS HAS BEEN OVERTURNED THE PAST COUPLE DAYS AND INSTABILITY WILL NOT BE AS STRONG AS YESTERDAY...THOUGH STRONG HEATING WILL AGAIN OCCUR WITHIN THE WARM SECTOR. AFTERNOON TEMPERATURES RISING THROUGH THE 80S AND SURFACE DEW POINTS HOLDING IN THE LOWER 60S ARE EXPECTED TO SUPPORT MODEST CAPE WITH MLCAPE FROM 1000-1500 J/KG. IN ADDITION...WEAK IMPULSE AIDING CONVECTIVE CLUSTER NOW MOVING INTO SERN TN WILL CONTINUE SEWD INTO SC AGAIN TODAY. GIVEN 40-50 KT EFFECTIVE SHEAR STILL IN PLACE...ACTIVITY MAY INCREASE IN COVERAGE AND INTENSITY AS STORMS SPREAD SEWD ACROSS THE SRN APPALACHIANS THIS AFTERNOON. SEVERITY WILL LIKELY NOT BE AS ROBUST AS YESTERDAY. HOWEVER...ENVIRONMENT STILL APPEARS SUPPORTIVE OF A FEW ORGANIZED CLUSTERS/SUPERCELLS SHOULD STORMS ROOT INTO MODEST MIXED-LAYER CAPE DURING THIS AFTERNOON. ...SERN KS ACROSS THE OZARK REGION INTO THE MID SOUTH... MCV FROM SMALL MCS WHICH ERODED ACROSS SWRN KS OVERNIGHT WAS EVIDENT ON SATELLITE IMAGERY OVER S-CENTRAL KS THIS MORNING. SMALL SCALE ENHANCEMENT OF LOW TO MID TROPOSPHERIC WINDS AND DEEP ASCENT SHOULD SUPPORT INCREASED CLUSTER OF STRONG TO SEVERE THUNDERSTORMS INTO SERN KS/FAR NERN OK AND SWRN MO AS CAP BREAKS THIS AFTERNOON. AIR MASS WILL LIKELY BECOME MODERATE TO STRONGLY UNSTABLE WITH STRONG HEATING ALONG AND SOUTH OF EFFECTIVE SURFACE FRONT NOW EXTENDING FROM SWRN MO WWD INTO FAR S-CENTRAL KS AND WSWWD ACROSS NWRN OK THIS MORNING. GIVEN LOCAL ENHANCEMENT OF DEEP LAYER SHEAR...STORMS MAY DEVELOP INTO SUPERCELLS THOUGH ITS MORE LIKELY STORMS WILL INCREASE INTO A CLUSTER/MCS WITH THREATS OF LARGE HAIL AND DAMAGING WINDS AS ACTIVITY MOVES SLOWLY SEWD THROUGH THE EVENING. ...CENTRAL HIGH PLAINS... RIDGING ALOFT WILL BUILD ACROSS THE CENTRAL ROCKIES TODAY. HOWEVER...SUFFICIENT WLY FLOW WILL PERSIST ACROSS NRN CO INTO ERN WY FOR MODEST DEEP LAYER SHEAR...WHERE FORECAST SOUNDINGS MAINTAIN 35-40 KT EFFECTIVE SHEAR. SURFACE WINDS ARE FORECAST BY ALL THE SHORT-TERM MODELS TO BACK TO SELY ACROSS THE CENTRAL HIGH PLAINS WITH WEAK LOW CENTER/TROUGH DEVELOPING INTO CENTRAL WY. THIS SHOULD SUSTAIN LOW 50F SURFACE DEW POINTS ALONG AND JUST EAST OF THE HIGHER TERRAIN FROM NRN CO INTO MUCH OF ERN WY. GIVEN STRONG HEATING...AIR MASS SHOULD BECOME MODERATELY UNSTABLE BY MID TO LATE AFTERNOON WITH INCREASING CONVECTION OVER HIGHER TERRAIN AND/OR INVOF LEE TROUGH. ACTIVITY WILL LIKELY PERSIST FOR SEVERAL HOURS WITH THREATS OF LARGE HAIL AND DAMAGING WINDS AS IT SHIFTS EWD OVER THE HIGH PLAINS LATE TODAY/THIS EVENING. CONSOLIDATION INTO A SMALL MCS IS POSSIBLE ALONG NOSE OF MODEST SLY H85 WIND MAX ACROSS WRN NEB LATER THIS EVENING. THOUGH ISOLATED SEVERE MAY DEVELOP INTO THE NRN HIGH PLAINS AND SWD INTO PORTIONS OF WEST TX ALONG LEE TROUGH TODAY...OVERALL SEVERE THREAT WARRANTS ONLY LOW PROBABILITIES ACROSS THESE AREAS. ...NRN INTERMOUNTAIN REGION... COMPLEX CONVECTIVE SCENARIO ACROSS THIS AREA TODAY AS RIDGE BUILDS OVER THE ROCKIES AND A STRONG UPPER LOW STAYS OFF THE CA COAST. CONSIDERABLE CLOUDINESS HAS OVERSPREAD MUCH OF THE NWRN INTERMOUNTAIN REGION THIS MORNING WHICH WILL LIMIT INSTABILITY AND RESULTANT THUNDERSTORM POTENTIAL TODAY. SHEAR WILL REMAIN MODEST AND SUPPORT SOME ORGANIZATION WITH ANY STORM WHICH CAN BE SUSTAINED OFF HIGHER TERRAIN...THOUGH OVERALL SEVERE THREAT APPEARS MARGINAL ATTM. ...WRN MT INTO THE NRN HIGH PLAINS... HEATING WILL BE ROBUST OVER THE NRN ROCKIES INTO CENTRAL MT AHEAD OF A SHORTWAVE TROUGH NOW EJECTING NWD OUT OF NV TODAY. THIS SYSTEM WILL LIKELY MAINTAIN SUFFICIENT MID LEVEL MOISTURE/LIFT FOR INCREASED THUNDERSTORMS OVER THE NRN ROCKIES THIS AFTERNOON WHICH WILL SPREAD NEWD ACROSS CENTRAL MT LATER TODAY AND THIS EVENING. HOWEVER...AIR MASS IS DRIER TODAY OVER MT WITH PW/S AT TFX LESS THAN .5 INCH AT 12Z. THUS...INSTABILITY WILL LIKELY BE MARGINAL AND WILL LIMIT SEVERITY WITH EXPECTED STORM CLUSTER/S TODAY. ISOLATED DAMAGING WINDS/LARGE HAIL MAY STILL ACCOMPANY STRONGER STORMS...THOUGH APPEARS OVERALL THREAT WARRANTS LOWER PROBABILITIES THAN EARLIER FORECAST. ..EVANS/GUYER.. 05/21/2006  From swody1 at goshenarc.org Sun May 21 20:03:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 16:03:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 212000 SWODY1 SPC AC 211958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT SUN MAY 21 2006 VALID 212000Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL PLAINS...OZARK PLATEAU...TN VALLEY AND SRN ATLANTIC SEABOARD... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL AND NRN HIGH PLAINS... ...SRN ATLANTIC SEABOARD/SRN APPALACHIANS AND TN VALLEY... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL TROUGH OVER THE ERN SEABOARD WITH AN MCS DEVELOPING ACROSS WRN SC. AT THE SFC...A NEARLY STATIONARY FRONT IS LOCATED FROM TN EXTENDING EWD ACROSS NRN SC. ALONG AND SOUTH OF THE BOUNDARY...SFC DEWPOINTS ARE IN THE 60S F WITH A POCKET OF MODERATE INSTABILITY CURRENTLY LOCATED IN NRN SC WHICH SHOULD SUSTAIN THE DEVELOPING MCS THIS AFTERNOON. IN ADDITION...OBJECTIVE ANALYSIS SHOWS 0-6 KM SHEAR VALUES EXCEEDING 30 KT NEAR AND TO THE NORTH OF THE BOUNDARY. AS A RESULT..THE ENVIRONMENT SHOULD BE SUPPORTIVE OF SUPERCELLS ESPECIALLY AS STORMS ORGANIZE AND MOVE INTO THE STRONGER INSTABILITY IN THE COASTAL PLAINS. STORM DEVELOPMENT WILL ALSO BE LIKELY FURTHER WEST ACROSS THE TN VALLEY LATER THIS AFTERNOON AND EARLY THIS EVENING. THE STRONGER CELLS SHOULD DEVELOP A POTENTIAL FOR LARGE HAIL AND ISOLATED WIND DAMAGE ACROSS TN...FAR NRN MS AND FAR NRN AL WHERE MLCAPE VALUES CURRENTLY RANGE FROM 1000-1500 J/KG AND MODERATE VERTICAL SHEAR EXISTS. ...CNTRL PLAINS AND OZARK PLATEAU... WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A SHORTWAVE TROUGH AND PLUME OF MID-LEVEL MOISTURE OVER CNTRL KS. AT THE SFC...A NEARLY STATIONARY FRONT IS LOCATED ACROSS ERN KS AND SRN MO. ALONG AND SOUTH OF THE BOUNDARY...AN AXIS OF INSTABILITY EXISTS WITH MLCAPE VALUES RANGING FROM 1500-2500 J/KG. IN ADDITION...REGIONAL PROFILERS SHOW MODERATE VERTICAL SHEAR PROFILES ACROSS MUCH OF ERN KS EXTENDING ESEWD ACROSS THE OZARK PLATEAU. AS A RESULT...THE ENVIRONMENT SHOULD BE SUPPORTIVE OF SUPERCELLS AS STORMS INITIATE AHEAD OF THE SHORTWAVE TROUGH ALONG THE BOUNDARY AND MOVE SEWD INTO THE INSTABILITY AXIS LATE THIS AFTERNOON. STEEP MID-LEVEL LAPSE RATES WILL BE FAVORABLE FOR LARGE HAIL. THE WIND DAMAGE POTENTIAL SHOULD ALSO INCREASE AS LOW-LEVEL LAPSE RATES STEEPEN AND THE STORMS INCREASE IN COVERAGE BY EARLY EVENING. ...CNTRL AND NRN HIGH PLAINS... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL RIDGE IN PLACE ACROSS THE HIGH PLAINS. SCATTERED THUNDERSTORMS ARE DEVELOPING UNDER THE RIDGE ALONG AND EAST OF A LEE SFC TROUGH. DEWPOINTS ARE IN THE 50S F WITH AN AXIS OF MODERATE INSTABILITY EXTENDING NNWWD FROM WRN KS ACROSS WRN NEB...FAR NE CO AND ERN WY. IN ADDITION TO THE INSTABILITY...REGIONAL PROFILERS SHOW SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. AS STORMS INCREASE IN COVERAGE AND MOVE EWD INTO THE INSTABILITY AXIS...THE SEVERE POTENTIAL SHOULD INCREASE. STEEP LAPSE RATES SHOULD FAVOR LARGE HAIL AND ISOLATED WIND DAMAGE AS THE PRIMARY SEVERE THREAT. FURTHER NORTHWEST ACROSS THE NRN ROCKIES...SCATTERED THUNDERSTORMS SHOULD DEVELOP THIS AFTERNOON AND MOVE NEWD ACROSS THE REGION. ALTHOUGH OBJECTIVE ANALYSIS SHOWS MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES IN PLACE ACROSS MOST OF THE REGION...INSTABILITY IS WEAKER FROM CNTRL MT EXTENDING WWD ACROSS ID. THIS WEAKNESS IN INSTABILITY SHOULD KEEP ANY SEVERE THREAT MARGINAL LATE THIS AFTERNOON AND EARLY THIS EVENING. ..BROYLES.. 05/21/2006  From swody1 at goshenarc.org Mon May 22 01:06:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 21 May 2006 21:06:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220103 SWODY1 SPC AC 220101 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0801 PM CDT SUN MAY 21 2006 VALID 220100Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE OZARK REGION ESE INTO TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS WRN PARTS OF THE NRN/CENTRAL PLAINS... ...OZARK REGION ESE TO TN VALLEY/SRN APPALACHIANS... QUASI-STATIONARY BOUNDARY REMAINED LOCATED FROM THE SRN APPALACHIANS WNWWD THROUGH SRN-WRN TN INTO NRN AR TO NORTH CENTRAL OK BEFORE BECOMING A LITTLE MORE DIFFUSE INTO THE SRN HIGH PLAINS. WATER VAPOR IMAGERY INDICATED SEVERAL WEAK SHORT WAVE TROUGHS/MCVS ALONG THE EXTENT OF THIS BOUNDARY WITH ONE LOCATED OVER THE TN VALLEY AND TWO UPSTREAM OVER WRN AR AND NERN OK/SERN KS. ASCENT ASSOCIATED WITH THESE FEATURES AS THEY TRACK ESE COMBINED WITH LOW-LEVEL WAA AND AIR MASS REMAINING MODERATELY UNSTABLE THROUGH 06-09Z ALONG THE SURFACE BOUNDARY WILL SUPPORT ADDITIONAL TSTMS. GREATEST THUNDERSTORM COVERAGE AND SEVERE POTENTIAL IS EXPECTED TO EXTEND FROM SRN MO/NRN AR INTO MIDDLE TN/FAR NRN AL...AND POSSIBLY NWRN GA THROUGH 12Z. EFFECTIVE SHEAR/INSTABILITY WILL FAVOR HAIL/ STRONG WIND GUSTS WITH ADDITIONAL STORMS. ...WRN PART OF THE NRN/CENTRAL PLAINS... THUNDERSTORMS OVER CENTRAL/ERN MT AND SWD FROM FAR ERN WY INTO WRN NEB/NWRN KS ARE BEING AIDED BY LARGE SCALE ASCENT ASSOCIATED WITH A COUPLE OF SHORT WAVE TROUGHS OVER MT AND WY. THIS ASCENT COMBINED WITH INCREASING WAA PER A STRENGTHENING SLY LLJ OVER WRN KS AND SSELY LLJ ALONG NRN HIGH PLAINS EXPECTED TO MAINTAIN POTENTIAL FOR ADDITIONAL THUNDERSTORMS THROUGH 06-09Z. GREATEST LIKELIHOOD FOR UPSCALE GROWTH INTO AN MCS IS EXPECTED WITH SRN CLUSTER OF STORMS OVER SWRN NEB/FAR NWRN KS WITH ACTIVITY SPREADING ESE OVERNIGHT ALONG INSTABILITY AXIS. STRONG WIND GUSTS AND HAIL ARE EXPECTED TO BE THE PRIMARY SEVERE THREATS. ...OK/TX PANHANDLES SWD THROUGH W TX... ISOLATED SEVERE STORMS WILL REMAIN POSSIBLE FOR THE NEXT FEW HOURS ACROSS WEST TX INCLUDING THE PANHANDLE...WHERE 00Z SOUNDINGS INDICATED A DEEPLY MIXED SUB-CLOUD LAYER SUPPORTIVE OF STRONG DOWNDRAFTS. DIABATIC COOLING SHOULD WEAKEN AVAILABLE INSTABILITY AND REDUCE THE LIKELIHOOD FOR SEVERE STORMS LATER THIS EVENING. ...INTERIOR PACIFIC NORTHWEST... INCREASING SLY MID LEVEL FLOW ACROSS ERN ORE/WA/ID/FAR WRN MT AND ASSOCIATED LARGE SCALE ASCENT WITHIN EXIT REGION OF THIS JET EXPECTED TO SUPPORT ADDITIONAL POTENTIAL FOR THUNDERSTORMS THROUGH THE EVENING. STRONG DEEP LAYER SHEAR WILL SUPPORT SOME STORM ORGANIZATION...BUT WEAK INSTABILITY SHOULD LIMIT SEVERE COVERAGE. ...ERN NEW ENGLAND... THE PORTION OF THE STRONGLY FORCED LINE OF LOW-TOPPED CONVECTION THAT HAD PRODUCED SOME SEVERE STORMS ACROSS NEW ENGLAND DURING THE LATE AFTERNOON HAS MOVED EWD OFFSHORE THE MA COAST...THUS LIMITING THE POTENTIAL FOR ADDITIONAL SEVERE STORMS. OVERALL PROBABILITY FOR THUNDERSTORMS WILL ALSO DECREASE OVERNIGHT AS THE ATTENDANT STRONG MID LEVEL IMPULSE...NOW CENTERED OVER NEW ENGLAND...TRACKS EWD TOWARD NOVA SCOTIA. ..PETERS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 06:04:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 02:04:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220601 SWODY1 SPC AC 220559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT MON MAY 22 2006 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE INTERIOR NW EWD ACROSS MT THEN SEWD TO THE CENTRAL HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE TN VALLEY TO NRN-ERN GA AND PARTS OF SRN SC... ...SYNOPSIS... STRONG SHORT WAVE TROUGH...CURRENTLY LOCATED JUST W OF SRN CA PER WATER VAPOR IMAGERY...IS EXPECTED TO EJECT NEWD AS A NEGATIVELY TILTED TROUGH ACROSS THE SWRN STATES REACHING THE FOUR CORNERS REGION BY 23/00Z...THEN INTO THE CENTRAL ROCKIES/HIGH PLAINS BY 12Z TUESDAY. ALTHOUGH THIS TROUGH SHOULD DE-AMPLIFY SOME AS IT TRACKS NEWD INTO THE PLAINS UPPER RIDGE...60-90 METER 500 MB HEIGHT FALLS WILL BE MAINTAINED ALONG ITS PATH. THE EJECTION OF THIS TROUGH IS IN RESPONSE TO UPSTREAM HEIGHT FALLS UNDERWAY 300-500 MILES W OF NRN CA/ORE...AS THE NERN PACIFIC DEEP UPPER LOW SETTLES SWD PRIOR TO 12Z TODAY. IN THE EAST...LONG WAVE TROUGH WILL REMAIN OVER THIS REGION WITH SRN PERIPHERY OF STRONGEST MID LEVEL FLOW EXTENDING FROM THE WRN GREAT LAKES SEWD ACROSS THE CENTRAL APPALACHIANS TO MID ATLANTIC STATES/ CAROLINAS. QUASI-STATIONARY SURFACE BOUNDARY SHOULD EXTEND FROM SC COAST NWWD THROUGH TN VALLEY INTO NRN AR AND ALONG THE OK/KS BORDER WHERE IT SHOULD BE MORE DIFFUSE. ...CENTRAL/NRN HIGH PLAINS... SSELY LOW-LEVEL FLOW WILL ALLOW MOISTURE TO CONTINUE TO RETURN NNWWD ACROSS THE CENTRAL/NRN PLAINS THIS FORECAST PERIOD. WEAK HEIGHT FALLS EXPECTED IN ADVANCE OF MAIN SWRN TROUGH AND POTENTIALLY ASSOCIATED WITH A WEAK IMPULSE TRACKING NEWD ACROSS THIS REGION WILL LIKELY AID IN THUNDERSTORMS THIS AFTERNOON FROM ERN CO TO ERN MT. THIS ACTIVITY WILL BE ALONG THE WRN EDGE OF THE DEEP MOISTURE WHERE MIXING AND SURFACE HEATING SHOULD WEAKEN THE CAP BY MID-LATE AFTERNOON. DEEP LAYER SHEAR WILL INITIALLY NOT BE STRONG...BUT EXPECTED TO INCREASE THIS EVENING/TONIGHT AS MID LEVEL WIND MAX WITH STRONGER SHORT WAVE TROUGH MOVES INTO CO. THUS...DESPITE SOME DECREASE IN INSTABILITY AFTER 00Z...STRONG ASCENT SPREADING NEWD WITH APPROACH OF UPPER TROUGH/PACIFIC COLD FRONT SHOULD ALLOW SEVERE THREAT TO PERSIST THIS EVENING/TONIGHT. ...INTERIOR NW INTO WRN MT... DEEP UPPER LOW REMAINING OVER THE NERN PACIFIC WILL MAINTAIN MODERATE SLY MID LEVEL FLOW ACROSS THIS REGION FOR MUCH OF THE FORECAST PERIOD. THE AMOUNT OF CLOUD COVER EXPECTED ACROSS THIS REGION TODAY MAY LIMIT THE DEGREE OF SURFACE HEATING. HOWEVER... RESIDUAL LOW-LEVEL MOISTURE BENEATH STEEP MID LEVEL LAPSE RATES SHOULD RESULT IN MLCAPE VALUES RANGING FROM 500-1000 J/KG...WITH THE HIGHER VALUES IN LOCATIONS WITH STRONGER SURFACE HEATING. DESPITE THE POTENTIAL FOR WEAKER INSTABILITY...LARGE SCALE ASCENT ASSOCIATED WITH A SHORT WAVE TROUGH ROTATING AROUND THE ERN PERIPHERY OF THE OFFSHORE UPPER LOW EXPECTED TO BE SUFFICIENT FOR THUNDERSTORMS TO DEVELOP BY THIS AFTERNOON. DEEP LAYER SHEAR WILL BE MORE THAN ADEQUATE TO SUPPORT ORGANIZED STORMS...WITH STRONG WIND GUSTS AND HAIL THE PRIMARY THREATS FROM THIS AFTERNOON INTO THE EVENING. ...TN VALLEY SE TO ERN GA/PARTS OF SRN SC... A COUPLE OF WEAK MID LEVEL IMPULSES ARE EXPECTED TO TRACK ESEWD ACROSS THE TN VALLEY TOWARD GA/SC TODAY. ALTHOUGH LOW LEVEL WINDS/CONVERGENCE SHOULD BE WEAK ALONG THE SURFACE BOUNDARY... ASCENT WITH THESE IMPULSES...MODERATE INSTABILITY AND 35-40 KT 0-6 KM SHEAR WILL LIKELY SUPPORT A FEW SEVERE STORMS. HAIL AND STRONG WIND GUSTS WILL BE THE PRIMARY THREAT...WHILE WEAK LOW-LEVEL WINDS SHOULD TEND TO MINIMIZE THE TORNADO POTENTIAL. ...LOWER CO RIVER VALLEY NEWD INTO CENTRAL/SRN ROCKIES... STRONG HEIGHT FALLS/FORCING EXPECTED TO SPREAD ACROSS THIS REGION TODAY AHEAD OF UPPER TROUGH. THIS COMBINED WITH STRONG SURFACE HEATING/OROGRAPHIC ASCENT EXPECTED TO SUPPORT WIDESPREAD CONVECTION ALONG THE TRACK OF THE UPPER TROUGH. HOWEVER...WEAK INSTABILITY SHOULD PRECLUDE A GREATER SEVERE THREAT. STEEP LAPSE RATES AND INCREASING DEEP LAYER SHEAR FROM W-E ACROSS THIS REGION SHOULD SUPPORT A LOW PROBABILITY FOR SEVERE HAIL/STRONG WIND GUSTS. ..PETERS/GRAMS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 12:58:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 08:58:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221255 SWODY1 SPC AC 221254 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT MON MAY 22 2006 VALID 221300Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER A LARGE PART OF THE INTERMOUNTAIN WEST AND CNTRL RCKYS/HI PLNS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE TN VLY AND SOUTHEAST... ...SYNOPSIS... AN ACTIVE SEVERE WEATHER DAY EXPECTED OVER PARTS OF THE INTERMOUNTAIN REGION AND RCKYS TODAY AS STRONG SHORTWAVE TROUGH NOW OVER SRN CA/NRN BAJA IS EJECTED RAPIDLY NEWD BY DEEP LOW OFF THE BC CST. EJECTING SYSTEM WILL INDUCE LEE TROUGHING OVER THE CNTRL/NRN HI PLNS...WITH SURFACE LOW EXPECTED TO DEEPEN ALONG THE TROUGH OVER S CNTRL MT TONIGHT/EARLY TUESDAY. IN THE EAST...A SERIES OF IMPULSES WILL MAINTAIN BROADER SCALE TROUGH OVER THE GRT LKS/NEW ENG....WITH ASSOCIATED SURFACE FRONT REMAINING MORE OR LESS STATIONARY FROM THE TN VLY TO THE SC CST. ...FOUR CORNERS REGION INTO CNTRL RCKYS/CNTRL HI PLNS... SEVERAL BANDS OF TSTMS EXPECTED TO PRECEDE AND POSSIBLY ACCOMPANY SRN CA SYSTEM AS IT MOVES E/NE ACROSS THE SRN/ERN GRT BASIN AND INTO THE CNTRL RCKYS LATER TODAY/TONIGHT. GIVEN STRONG BACKGROUND WIND FIELD /500 MB SPEEDS INCREASING TO AROUND 50 KTS/...INVERTED VEE SOUNDINGS EXPECTED WITH DAYTIME HEATING...AND SUSTAINED FORCING FOR ASCENT...SOME OF THE STORM BANDS MAY CONTAIN BOTH LARGE AND SMALL SCALE BOWING SEGMENTS WITH HIGH WIND. DOWNSTREAM FROM THE MORE DYNAMICALLY-DRIVEN CONVECTION...OTHER STORMS EXPECTED TO FORM THIS AFTERNOON THROUGH TONIGHT IN CONFLUENT ...WEAKLY UPSLOPE ENVIRONMENT ALONG THE CO/SRN WY FRONT RANGE EWD INTO THE CNTRL HI PLNS OF ERN CO/SE WY AND THE NEB PANHANDLE. DEVELOPMENT MAY BE MODULATED...AND POSSIBLY ENHANCED...INVOF CONVECTIVE OUTFLOW/LOW LEVEL MOISTURE AXES LEFT BY OVERNIGHT MCS IN KS. GIVEN INCREASINGLY STRONG WIND FIELDS...AND PRESENCE OF SUBSTANTIAL DIRECTIONAL COMPONENT TO THE LOW LEVEL SHEAR...POTENTIAL WILL EXIST FOR SUPERCELLS WITH LARGE HAIL/HIGH WIND AND PERHAPS A COUPLE TORNADOES. THIS ACTIVITY LIKELY WILL BE OVERTAKEN BY FASTER MOVING STORMS ARRIVING FROM THE WRN/SRN CO. THE RESULTING CLUSTERS SHOULD CONTINUE GENERALLY E IN A DIMINISHING STATE INTO PARTS OF NRN KS AND WRN/CNTRL NEB EARLY TUESDAY. ...NRN INTERMOUNTAIN REGION... MODERATE SURFACE HEATING OF STRONGLY SHEARED ENVIRONMENT MAY YIELD ANOTHER DAY OF STRONG STORMS/POSSIBLE SUPERCELLS OVER WRN ID AND ERN WA/ORE. THIS CORRIDOR SHOULD EXPERIENCE THE STRONGEST/DEEPEST FORCING FOR ASCENT IN DEFORMATION ZONE BETWEEN EJECTING SYSTEM TO THE S...AND NEARLY STATIONARY LOW OFF THE BC/WA CST. SOME OF THESE STORMS MAY REMAIN STRONG INTO THE NIGHT IN NRN ID. ...TN VLY TO SC CST... ANOTHER ROUND OF STRONG TO SEVERE DIURNAL STORMS EXPECTED ALONG STALLED FRONT IN THE SOUTHEAST. BOUNDARY WILL REMAIN PARALLEL TO MODERATE DEEP WNWLY SHEAR. DETAILS OF CONVECTIVE EVOLUTION WILL ONCE AGAIN BE DOMINATED BY STORM-SCALE AND...POSSIBLY...ONCE AGAIN BY OROGRAPHIC FACTORS ASSOCIATED WITH THE SRN APLCNS. CLOUDS OVER THE SC MIDLANDS WILL LIMIT LOW LEVEL DESTABILIZATION IN THAT REGION. BUT AREA SOUNDINGS SUGGEST SUFFICIENT SHEAR/INSTABILITY TO SUPPORT DEVELOPMENT OF SUSTAINED...MULTICELL FORWARD-PROPAGATING CLUSTERS WITH HAIL/HIGH WIND...WITH INITIATION FAVORED IN SPOTS RECEIVING MORE SUN. ..CORFIDI/GRAMS.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 16:40:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 12:40:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221628 SWODY1 SPC AC 221626 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1126 AM CDT MON MAY 22 2006 VALID 221630Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM JUST WEST OF THE ROCKIES EWD ACROSS THE HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE NRN INTERMOUNTAIN WEST AND NRN ROCKIES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SERN KS AND THE OZARK PLATEAU... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE SRN APPALACHIANS ACROSS SC... ...ALONG/JUST WEST OF ROCKIES EWD ACROSS THE HIGH PLAINS... DEEP...NEGATIVELY-TILTED TROUGH WITH STRONGEST ENERGY NOW APPROACHING THE LOWER CO RIVER VALLEY WILL ENHANCE THUNDERSTORM POTENTIAL ACROSS MUCH OF THE WRN U.S. TODAY. DEEP SLY FLOW AND INCREASED MID LEVEL MOISTURE IS SUSTAINING WIDESPREAD CLOUDS OVER A LARGE PART OF THE GREAT BASIN INTO THE PAC NW WHICH WILL LIMIT HEATING AND INSTABILITY OVER THESE REGIONS. APPEARS JUST EAST OF THIS CLOUD SHIELD...INTO THE SRN ROCKIES AND ERN PORTIONS OF THE INTERMOUNTAIN WEST...HEATING WILL ALLOW STEEP LOW LEVEL LAPSE RATES TO DEVELOP UNDER MOISTENING MID LEVELS AND INCREASING LARGE SCALE ASCENT THIS AFTERNOON. TEMPERATURES ARE ALREADY APPROACHING 80F OVER WRN CO...WITH FURTHER HEATING THROUGH THE DAY. THUS...INCREASING THUNDERSTORMS WILL SPREAD A THREAT OF HAIL AND DAMAGING WINDS EWD INTO THE SRN/CENTRAL ROCKIES THROUGH THE EARLY EVENING. EAST OF THE ROCKIES...SELY WINDS AND BOUNDARY LAYER MOISTURE HAVE BECOME MORE FAVORABLE TODAY FOR SEVERE THUNDERSTORMS THAN THE PAST COUPLE DAYS FROM SERN MT INTO ERN NM. IN ADDITION...PRESSURE FALLS AND SSWLY WINDS ALOFT WILL STRENGTHEN LATER TODAY AHEAD OF APPROACHING UPPER TROUGH...INCREASING DEEP LAYER SHEAR AS FAR SOUTH AS ERN NM. THUS...INCREASING MLCAPE OVER THE HIGH PLAINS THROUGH THE AFTERNOON WILL BECOME MORE FAVORABLE FOR INTENSE THUNDERSTORMS PERSISTING EWD OVER THE HIGH PLAINS THROUGH THE EVENING. FORECAST SOUNDINGS INDICATE SHEAR ADEQUATE FOR SUPERCELLS...WITH TORNADO POTENTIAL INCREASING INTO NWRN KS/NERN CO/NEB PANHANDLE BY THE EARLY EVENING WHERE RUC DEVELOPS 40 KT SSELY LLJ BY 00Z. ISOLATED DAMAGING WINDS AND VERY LARGE HAIL MAY ALSO ACCOMPANY STRONGER CORES THIS EVENING. OVERALL EVOLUTION INTO SEVERAL CLUSTERS AND SMALL MCSS APPEARS LIKELY LATER THIS EVENING...ESPECIALLY INTO WRN KS/WRN NEB ALONG NOSE OF STRONGER SLY LLJ. ...FAR ERN ORE/ERN WA INTO WRN MT... THIN CLOUDS WITH SOME BREAKS ARE EVIDENT OVER PORTIONS OF WRN ID INTO FAR NERN ORE THIS MORNING. SHEAR WILL REMAIN QUITE STRONG OVER THIS REGION UNDER 45 KT SLY MID LEVEL WINDS AND MID LEVELS WILL COOL UNDER -16C H5 THERMAL TROUGH. THUS...EVEN MODEST HEATING WILL PROVIDE SUFFICIENT DESTABILIZATION FOR A FEW SEVERE THUNDERSTORMS OVER HIGHER TERRAIN AND NEAR SURFACE LOW/COLD FRONT MOVING EWD ACROSS NRN ID INTO WRN MT TODAY. ...SERN KS ACROSS THE OZARK PLATEAU... REFERENCE SWOMCD 932 FOR SHORT-TERM GUIDANCE ON THIS REGION. MUCH STRONGER HEATING/INSTABILITY TODAY AS COMPARED TO YESTERDAY AHEAD OF SLOW MOVING MCV NOW OVER S-CENTRAL KS. EXPECT WEAKLY SHEARED CLUSTER OF STRONG/SEVERE THUNDERSTORMS WILL EVOLVE AND REMAIN FOCUSED IMMEDIATELY AHEAD OF MCV AS IT TRACKS SLOWLY EWD ACROSS SERN KS INTO SWRN MO. LARGE HAIL AND DAMAGING WINDS MAY ACCOMPANY THIS ACTIVITY. ...TN INTO SC... SURFACE BOUNDARY REMAINS IN PLACE OVER THIS REGION AND SHOULD FOCUS THUNDERSTORMS LATER TODAY AS CAP WEAKENS...AS HAS BEEN THE CASE FOR A COUPLE DAYS NOW. HOWEVER...APPEARS WEAKER SHEAR WILL LIMIT ORGANIZED/SUSTAINED SEVERE THREAT OVER THE MID SOUTH AND TN RIVER VALLEY. SHEAR REMAINS STRONGER ALONG PORTION OF THE FRONT PERSISTING ACROSS SC...WHERE ERODING CLOUDS ARE NOW SUPPORTING ROBUST HEATING ONCE AGAIN. OVERALL THREAT MAY BE LESS THAN THE PAST TWO DAYS...THOUGH ENVIRONMENT WILL STILL FAVOR A FEW ORGANIZED CLUSTERS AS STORMS DEVELOP AND SPREAD ESEWD THROUGH THE EARLY EVENING. ..EVANS/GUYER.. 05/22/2006  From swody1 at goshenarc.org Mon May 22 21:06:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 17:06:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 222101 SWODY1 SPC AC 222059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0359 PM CDT MON MAY 22 2006 VALID 222000Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLATEAU REGION.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL ROCKIES FROM SERN MT INTO NRN NM.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS CENTRAL AND SERN KS.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SC AND GA.... ...SYNOPSIS... NEGATIVELY TILTED MID/UPPER LEVEL TROUGH IS CURRENTLY MOVING NEWD OVER WRN/SCENTRAL NV ACCORDING TO LATEST WATER VAPOR SATELLITE LOOP. WIDESPREAD AREA OF THUNDERSTORMS EXTENDS FROM SERN WY SEWD/SWD THRU WRN CO INTO CENTRAL NM AS INDICATED ON LATEST LIGHTNING NETWORK. THIS ACTIVITY IS OCCURRING AHEAD OF SURFACE TROUGH/FRONTAL BOUNDARY WHICH IS EXPECTED TO ACCOMPANY THE MID/UPPER LEVEL TROUGH EWD/NEWD THROUGH THE REMAINDER OF THE PERIOD. ...CENTRAL AND SERN KS... MORNING CONVECTION AND ASSOCIATED MCV JUST E OF ICT IS MOVING SLOWLY EWD WITH NEW CONVECTION DEVELOPING RIGHT NEAR THE MCV. AIR MASS CONTINUES TO DESTABILIZE N-NE-E OF THE MCV WITH MLCAPE BETWEEN 1500-2000 J/KG. ALSO...CIRRUS CANOPY FROM CURRENT CONVECTION HAS RETARDED FURTHER DESTABILIZATION ESE AND S WHERE CAPPING INVERSION REMAINS. THUS...LOOKS LIKE CONTINUED THREAT FOR HAIL AND DAMAGING WINDS WILL BE FROM S CENTRAL INTO SERN KS...POSSIBLY INTO THE EXTREME WRN COUNTIES OF SWRN MO. ALSO ADDITIONAL STRONG/SEVERE THUNDERSTORMS COULD DEVELOP NWD BETWEEN HUT AND SLN...AND JUST S OF THE KS/OK BORDER FROM PNC TO NEAR GMJ. ...SERN MT SWD INTO E CENTRAL NM... STRONG/SEVERE THUNDERSTORMS WILL CONTINUE TO DEVELOP AHEAD OF NEGATIVELY TILTED TROUGH/ASSOCIATED SURFACE TROUGH/FRONTAL BOUNDARY. FORECAST SOUNDINGS SHOW INVERTED-V TYPE PROFILES WITH 700-500 MB LIFTED INDICES AROUND -4 ACROSS WRN CO INTO CENTRAL NM. IN ADDITION...MID LEVEL LAPSE RATES BETWEEN 7.5 TO 9C/KM ARE EXPECTED THIS AFTERNOON INDICATING THE THREAT FOR DOWNBURST WINDS AND POSSIBLY HAIL AS MID LEVEL COLD POOL MOVES ACROSS PARTS OF CO. ...PARTS OF NRN PLATEAU REGION... LOW PRESSURE AHEAD OF ADVANCING TROUGH WILL BE MOVING ACROSS THIS REGION. ONCE AGAIN...AIR MASS IS EXPECTED TO DESTABILIZE AND STEEPENING LAPSE RATES TO AROUND 8C/KM WOULD SUPPORT STRONG/SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND POSSIBLY HAIL. ...PARTS OF SC/E CENTRAL GA... REMNANTS OF QUASISTATIONARY BOUNDARY EXTENDS E-W ACROSS EXTREME SRN SC THROUGH CENTRAL GA. STORMS ARE DEVELOPING IN THE VICINITY OF THE FRONT AT THIS TIME WITH MLCAPES APPROACHING 1000 J/KG. ISOLATED STORMS EXPECTED THROUGH EARLY TONIGHT POSSIBLY PRODUCING DAMAGING WINDS. ..MCCARTHY.. 05/22/2006  From swody1 at goshenarc.org Tue May 23 01:04:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 22 May 2006 21:04:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230101 SWODY1 SPC AC 230059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT MON MAY 22 2006 VALID 230100Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS HIGH PLAINS FROM SERN MT TO NERN NM... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE INTERIOR NORTHWEST... ...HIGH PLAINS FROM SERN MT TO NERN NM... STRONG NEGATIVELY TILTED SHORT WAVE TROUGH...NOW LOCATED OVER THE FOUR CORNERS REGION...WILL CONTINUE TO TRACK NEWD REACHING THE CENTRAL/NRN HIGH PLAINS FROM ERN CO TO ERN WY/SERN MT BY 12Z TUESDAY. ASCENT SPREADING NEWD AHEAD OF THIS TROUGH WILL CONTINUE TO PROMOTE THUNDERSTORM DEVELOPMENT THROUGH THE REMAINDER OF THE FORECAST PERIOD FROM NERN NM/CO/SRN WY AND NNEWD INTO REST OF WY/WRN NEB/WRN DAKOTAS/ERN MT. DESPITE SOME WEAKENING OF INSTABILITY...INCREASING EFFECTIVE DEEP LAYER SHEAR DUE TO 50-60 KT SWLY MID LEVEL JET MOVING INTO CO/WRN NEB AND STRENGTHENING SLY LLJ TO 40-50 KT ALONG WRN PLAINS WILL SUPPORT STORM ORGANIZATION/ ADDITIONAL SEVERE THREAT. LARGE HAIL AND STRONG WIND GUSTS/DAMAGING WINDS SHOULD REMAIN THE PRIMARY THREATS THIS EVENING/TONIGHT. ...INTERIOR NW... EARLY EVENING WATER VAPOR IMAGERY SHOWED A SHORT WAVE TROUGH EXTENDING FROM NRN CA/NWRN NV TO OFFSHORE OF ORE. THIS IMPULSE IS PROGGED TO CONTINUE ROTATING NE THEN MORE NWD AROUND THE ERN PERIPHERY OF A LARGE DEEP UPPER LOW CENTERED 650 MILES WEST OF THE ORE/WA COAST LINE. ASCENT AHEAD OF THIS TROUGH WILL CONTINUE TO AID IN ADDITIONAL THUNDERSTORM DEVELOPMENT ACROSS MUCH OF THE INTERIOR NW. STRONG DEEP LAYER SLY SHEAR PROFILES PER 00Z SOUNDINGS COMBINED WITH MARGINAL INSTABILITY WILL MAINTAIN A SEVERE THREAT WITH BOTH BOWING SEGMENTS AND SUPERCELLS THROUGH THE EVENING. A DECREASING TREND IN THE SEVERE POTENTIAL IS EXPECTED LATER TONIGHT AS THE AIR MASS STABILIZES THROUGH DIABATIC COOLING AND IS CONVECTIVELY OVERTURNED BY ONGOING ACTIVITY. ...ERN KS/SWRN MO/NWRN AR... WEAK MCV LOCATED OVER SERN KS/SWRN MO IS EXPECTED TO MOVE VERY LITTLE OVERNIGHT AS IT REMAINS WITHIN THE AXIS OF THE UPPER RIDGE. WEAK ASCENT ALONG ERN-NRN PERIPHERIES OF THIS FEATURE ACROSS NWRN AR/SWRN MO AND EAST CENTRAL KS MAY SUPPORT A FEW ADDITIONAL STRONG/ POTENTIALLY PULSE SEVERE STORMS. HOWEVER...BOUNDARY LAYER COOLING IS EXPECTED TO LIMIT THE OVERALL SEVERE THREAT. THUS...HAVE REDUCED SEVERE PROBABILITIES ACROSS THIS REGION. ...NRN PARTS OF MS/AL TO SRN SC... AIR MASS WILL CONTINUE TO STABILIZE THIS EVENING ACROSS THIS REGION LIMITING ANY ADDITIONAL THREAT OF THUNDERSTORMS AND ATTENDANT SEVERE THREAT. ..PETERS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 06:02:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 02:02:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230559 SWODY1 SPC AC 230557 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1257 AM CDT TUE MAY 23 2006 VALID 231200Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF CENTRAL/NRN PLAINS EWD TO SRN MN/CENTRAL IA/NWRN MO... ...SYNOPSIS... STRONG NEGATIVELY TILTED MID/UPPER LEVEL SHORT WAVE TROUGH WILL TRACK NEWD ACROSS THE NRN HIGH PLAINS TODAY...THEN TURN EWD ACROSS SD/NEB TONIGHT. BAND OF 45-55 KT MID LEVEL FLOW WITHIN THE SRN-ERN PERIPHERY OF THIS TROUGH WILL SPREAD ACROSS MUCH OF THE CENTRAL/NRN PLAINS TODAY REACHING THE MID MO RIVER VALLEY TONIGHT. IN THE LOW LEVELS...A REMNANT SURFACE BOUNDARY/MOISTURE AXIS EXTENDED FROM THE GULF COAST STATES/LOWER MS VALLEY NWWD ACROSS THE OZARKS TO ERN KS/NEB TO WRN SD. NRN EXTENT OF THIS BOUNDARY WILL DEVELOP NEWD AS A PACIFIC COLD FRONT SPREADS ENEWD ACROSS SD/NEB/KS. PRIMARY SURFACE LOW IS PROGGED TO TRACK NEWD FROM ERN MT INTO SRN CANADA... WHILE A SECONDARY LOW DEVELOPS OVER CENTRAL/ERN SD AND/OR EXTENDS INTO ERN NEB BY MID-LATE AFTERNOON. IN THE WEST...ANOTHER SHORT WAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF THE DEEP LOW OVER THE NERN PACIFIC IS EXPECTED TO MOVE INLAND ACROSS THE PACIFIC NW TODAY. ...PARTS OF CENTRAL/NRN PLAINS TO SRN MN/CENTRAL IA/NWRN MO... THUNDERSTORMS...SOME POTENTIALLY SEVERE...ARE EXPECTED TO BE ONGOING AT 12Z THIS MORNING ACROSS WRN PARTS OF THE CENTRAL PLAINS TO SWRN SD WITHIN DEEP LAYER ASCENT ALONG NOSE OF STRONG NOCTURNAL SLY LLJ OVER THE WRN PLAINS AND WITH HEIGHT FALLS AHEAD OF APPROACHING TROUGH. THIS ACTIVITY IS EXPECTED TO SPREAD NEWD TOWARD THE CENTRAL DAKOTAS...BUT SHOULD WEAKEN AS THE LLJ DECREASES IN STRENGTH THIS MORNING. SLY L0W LEVEL FLOW WILL PERSIST ACROSS THE CENTRAL U.S. WITH LOWER- MID 60S SURFACE DEWPOINTS RETURNING NWD ACROSS THE ERN PLAINS AND LOWER MO RIVER VALLEY TO WRN MN. STEEP LAPSE RATES ATOP THIS MOISTURE RETURN COUPLED WITH STRONG SURFACE HEATING WILL CONTRIBUTE TO MODERATE INSTABILITY WITHIN THE WARM SECTOR BY THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP INITIALLY ACROSS CENTRAL SD IN THE VICINITY OF THE SURFACE LOW BY MID AFTERNOON... AND THEN SWD ALONG A DRY LINE INTO CENTRAL NEB....WITH MORE ISOLATED DEVELOPMENT POSSIBLE SWD INTO CENTRAL KS. MODERATE INSTABILITY COMBINED WITH INCREASING SLY LLJ ACROSS THE ERN PLAINS BENEATH STRENGTHENING SWLY MID LEVEL FLOW WILL RESULT IN FAVORABLE DEEP LAYER AND DIRECTIONAL SHEAR FOR SUPERCELLS. LARGE HAIL... SOME POSSIBLY VERY LARGE...AND DAMAGING WINDS WILL BE LIKELY. IN ADDITION...LOW-LEVEL DIRECTIONAL SHEAR/CURVED HODOGRAPHS SUGGEST POTENTIAL FOR ISOLATED TORNADOES WITH INITIAL ACTIVITY AND AS STORMS DEVELOP EWD ACROSS SD/NEB/NRN KS TOWARD WRN IA. SLY LLJ IS EXPECTED TO STRENGTHEN THIS EVENING AND VEER OVERNIGHT FROM THE ERN PLAINS INTO NRN MO TO UPPER MS VALLEY AS 60-90 METER HEIGHT FALLS DEVELOP EWD ACROSS SD INTO NRN IA/MN WITH THE APPROACH OF THE UPPER TROUGH. THIS SUGGESTS UPSCALE GROWTH OF INITIAL ACTIVITY INTO CLUSTERS OF STORMS...THEN A FORWARD PROPAGATING MCS MOVING EWD TOWARD SWRN MN/WRN IA THIS EVENING...POTENTIALLY TURNING SEWD ACROSS IA/NRN MO AND ERN KS TONIGHT. DAMAGING WINDS SHOULD BECOME PRIMARY SEVERE THREAT WITH THE MCS...THOUGH HAIL SHOULD REMAIN A THREAT AS WELL. ...WRN MO/NWRN AR... ISOLATED STORMS...SOME SEVERE...MAY DEVELOP ALONG THE SURFACE BOUNDARY EXTENDING SSEWD THROUGH WRN MO INTO NWRN AR AS THE AIR MASS BECOMES MODERATELY UNSTABLE THIS AFTERNOON. DEEP LAYER SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORMS...BUT MODELS SUGGEST SOMEWHAT WEAK UPPER FORCING WITHIN THE RIDGE AXIS SHOULD LIMIT COVERAGE OF SEVERE WEATHER. ...ERN MT/WRN ND... THUNDERSTORMS MAY BE ONGOING AT THE START OF DAY 1 ACROSS THE NRN HIGH PLAINS. MODELS SUGGEST THIS ACTIVITY SHOULD PERSIST THROUGH THE DAY WITHIN DEFORMATION ZONE ALONG NWRN PERIPHERY OF UPPER TROUGH. INSTABILITY WILL BE WEAK...BUT DEEP LAYER SHEAR MAY BECOME SUFFICIENT FOR A FEW SEVERE STORMS MAINLY ACROSS ERN MT INTO WRN ND. ...MUCH OF WA/CENTRAL-ERN ORE/WRN-NRN ID... ASCENT SPREADING NEWD ACROSS THE PACIFIC NORTHWEST TODAY AHEAD OF THE APPROACHING PACIFIC SHORT WAVE TROUGH IS EXPECTED TO PROVE SUFFICIENT IN SUPPORTING THUNDERSTORMS MOVING/DEVELOPING FROM SW-NE ACROSS THIS REGION TODAY INTO THIS EVENING. ALTHOUGH INSTABILITY IS EXPECTED TO BE MARGINAL...SURFACE HEATING COMBINED WITH STEEPENING LAPSE RATES AND STRONG DEEP LAYER SHEAR SHOULD SUPPORT A FEW SEVERE STORMS...ESPECIALLY ALONG/E OF THE WA/ORE CASCADES. ..PETERS/GRAMS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 12:53:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 08:53:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231250 SWODY1 SPC AC 231248 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 AM CDT TUE MAY 23 2006 VALID 231300Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CNTRL AND NRN PLNS... ...SYNOPSIS... NEG TILT TROUGH NOW EJECTING NE ACROSS THE CNTRL RCKYS SHOULD TURN MORE ELY AND EVOLVE INTO A CLOSED LOW AS IT MOVES OFF THE HIGHER TERRAIN LATER TODAY/TONIGHT. THE LOW SHOULD REACH NE SD BY 12Z WEDNESDAY AS DEEP LOW PERSISTS OFF THE BC CST. AT LWR LEVELS... SURFACE LOW NOW OVER SE MT SHOULD CONTINUE NE INTO CANADA AND WEAKEN AS A NEW CIRCULATION CENTER DEVELOPS CLOSER TO TRACK OF UPR LOW IN NRN SD. TRAILING COLD FRONT/LEE TROUGH ATTENDING THE LOW SHOULD BECOME BETTER DEFINED ACROSS THE CNTRL PLNS DURING THE DAY TODAY AS EFFECTS OF OVERNIGHT MCS DIMINISH. WARM FRONT SHOULD ALSO BECOME BETTER DEFINED...EXTENDING S/SE FROM THE LOW INTO LWR MO AND LWR TN VLYS. ...CNTRL/NRN PLNS... FOCUS FOR ANOTHER FAIRLY ACTIVE SEVERE WEATHER DAY WILL SHIFT E/NE INTO THE CNTRL/NRN PLNS...WHERE ASCENT AND SHEAR WILL BE MAXIMIZED AHEAD OF CNTRL RCKYS/HI PLNS TROUGH. SURFACE HEATING AND MID LEVEL COLD ADVECTION WILL FOSTER SUBSTANTIAL DESTABILIZATION AHEAD OF MERGING PACIFIC COLD FRONT/LEE TROUGH FROM SD SWD INTO KS. SBCAPE SHOULD RANGE FROM 1000 TO 2000 J/KG FROM SD SWD INTO NRN/ERN KS ...WITH GREATER MOISTURE AVAILABILITY/STRONGER HEATING COMPENSATING FOR WARMER MID LEVEL TEMPS/WEAKER FORCING WITH SWD EXTENT. AMPLE SHEAR WILL BE PRESENT FOR SUSTAINED STORMS/SUPERCELLS. FORCING/INSTABILITY CONSIDERATIONS SUGGEST THAT TSTMS WILL FIRST DEVELOP IN SD/NRN NEB...CLOSER TO DEVELOPING SURFACE WAVE. ACTIVITY SHOULD THEN BUILD SWD WITH TIME...LIKELY INTO KS BY EARLY EVENING. MODERATE TO STRONG /35-45 KT/ SWLY MID LEVEL JET...CHARACTER OF FORCING AND LIKELIHOOD FOR DEEP MIXING SUGGEST THAT STORMS IN NEB SHOULD TEND TO BE OUTFLOW-DOMINANT...WITH FAIRLY RAPID EVOLUTION INTO FORWARD-PROPAGATING LINES/BANDS WITH HIGH WIND. CELLS ON THE SRN FRINGE OF THIS ACTIVITY COULD ALSO POSE A THREAT FOR LARGE HAIL AND POSSIBLY A TORNADO OR TWO INTO NRN KS. THE STORMS SHOULD EVOLVE INTO AN MCS THAT EVENTUALLY TURNS MORE ESE TOWARD MO/WRN AND SRN IA TONIGHT. IN SD AND NRN ND...CLOUDS AND PROXIMITY OF DEVELOPING SURFACE LOW SHOULD KEEP BOUNDARY LAYER MIXING MORE LIMITED. WHILE DEEP SHEAR WILL BE WEAKER RELATIVE TO POINTS FARTHER S...BACKED NEAR-SURFACE FLOW WILL CONTRIBUTE TO ENHANCED LOW LEVEL SHEAR. STORMS IN THIS CORRIDOR MAY THEREFORE POSE A THREAT FOR TORNADOES IN ADDITION TO HAIL AND LOCALLY DAMAGING WIND. FARTHER N/NW...LOW LEVEL CONVERGENCE INVOF DEFORMATION ZONE NW OF EJECTING TROUGH...COUPLED WITH DAYTIME HEATING...MAY YIELD A FEW SMALL CLUSTERS OF STORMS WITH MARGINALLY SEVERE HAIL/WIND IN ERN MT/WRN ND. IN ADDITION...WIDELY SCATTERED ELEVATED STORMS... A FEW POSSIBLY WITH HAIL...MAY PERSIST/DEVELOP IN WARM ADVECTION ZONE OVER ERN ND/NRN MN. ...PAC NW INTO NRN ID... LARGE SCALE ASCENT WILL INCREASE OVER PARTS OF WA/ORE AND ID LATER TODAY AS SHORTWAVE IMPULSE NOW APPROACHING THE NRN CA CST SWEEPS NEWD. WHILE INSTABILITY WILL REMAIN LIMITED AND LOW LEVEL CONVERGENCE WEAK...DIFFERENTIAL HEATING AND LARGE SCALE FORCING MAY PROVE SUFFICIENT FOR SCATTERED LATE DAY/EVENING STORMS. SHEAR PROFILES AND COOL AIR ALOFT COULD YIELD A FEW SEVERE CELLS... ESPECIALLY ALONG/E OF THE WA/ORE CASCADES. ..CORFIDI/MEAD/GRAMS.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 16:27:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 12:27:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231622 SWODY1 SPC AC 231620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT TUE MAY 23 2006 VALID 231630Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF THE NRN AND CENTRAL PLAINS... ...NRN/CENTRAL PLAINS... COMPACT MID/UPPER LEVEL SYSTEM WITH ASSOCIATED 45+ KT SSWLY MID LEVEL JET WILL SPREAD EWD ACROSS THE CENTRAL AND NRN PLAINS TODAY. SYSTEM WILL OVERSPREAD A MODEST LATE-MAY BOUNDARY LAYER WITH CURRENT SURFACE DEW POINTS IN THE LOWER-MID 60S AS FAR NORTH AS SERN SD THIS MORNING. STRONG HEATING WILL BE COMMON TODAY AHEAD OF ADVANCING SURFACE COLD FRONT/TROUGH MOVING W-E ACROSS THE PLAINS AND SUPPORT TEMPERATURES APPROACHING 90F INTO NEB/SD. HEATING AND MID LEVEL DRY INTRUSION WILL SUPPORT STRONG MIXING/DRYING ALONG WRN EDGE OF LOW LEVEL MOIST AXIS...THOUGH MORNING UA ANALYSES/SOUNDINGS INDICATE BOUNDARY LAYER MOISTURE REMAINS SUFFICIENTLY DEEP FOR 60-65F SURFACE DEW POINTS TO SURVIVE DEEP MIXING ACROSS ERN KS INTO SERN SD. THIS WILL SUPPORT A MODERATE TO STRONGLY UNSTABLE AIR MASS BY THE LATE AFTERNOON...WITH RAPID SEVERE THUNDERSTORM DEVELOPMENT LIKELY AROUND 20-21Z ALONG SURFACE TROUGH FROM CENTRAL SD INTO NEB/FAR NRN KS. SHEAR WILL BECOME INCREASINGLY FAVORABLE FOR SUPERCELLS...AND POSSIBLY A FEW TORNADOES...AS REGION IS PLACED UNDER 35-40 KT SLY LLJ. LARGE SURFACE T/TD SPREADS SHOULD RESULT IN RELATIVELY HIGH CLOUD BASES/LCLS AND MAY INHIBIT PERSISTENT TORNADO THREAT WITH DEVELOPING SUPERCELLS. LARGE HAIL AND DAMAGING WINDS WILL BE PREVAILING SEVERE THREAT AS STORMS CONSOLIDATE INTO ONE OR MORE SQUALL LINES/CLUSTERS AND SHIFT ENEWD THROUGH THE EVENING. MORE ORGANIZED CLUSTERS/MCSS WILL LIKELY TURN MORE ESEWD AFTER DARK AND SPREAD ISOLATED SEVERE THREAT INTO MORE OF WRN IA/MO AND SRN/ERN KS. STRONG ASCENT/CONVERGENCE WILL ALSO SUPPORT THUNDERSTORM DEVELOPMENT NEAR LOW CENTER/OCCLUDED FRONT OVER WRN HALF OF ND INTO FAR NERN MT PRIOR TO 21Z. MLCAPE AND DEEP LAYER SHEAR WILL BE WEAKER IN CLOSER PROXIMITY TO MID LEVEL LOW AND ALONG NWRN PORTION OF LOW LEVEL MOISTURE AXIS. HOWEVER...MLCAPE AROUND 1000 J/KG AND STRONG ASCENT WILL LIKELY SUPPORT A SEPARATE CLUSTER OF SEVERE THUNDERSTORMS INTO WRN ND/FAR NERN MT THROUGH THE EARLY EVENING. ...PAC NW EAST OF THE CASCADES... WELL DEFINED SHORTWAVE TROUGH WILL REMAIN NEGATIVELY TILTED AS IT MOVES NNEWD ACROSS ORE AND WA TODAY. CLOUDS AHEAD OF THIS FEATURE MAY LIMIT HEATING/OVERALL INSTABILITY ACROSS CENTRAL/ERN ORE/WA. HOWEVER...SUFFICIENT HEATING WILL OCCUR FOR MODEST INSTABILITY AND A GENERAL INCREASE IN DEEP MOIST CONVECTION SPREADING NWD THROUGH THE AFTERNOON AHEAD OF APPROACHING SYSTEM. OVERALL SETUP APPEARS MARGINAL FOR SUSTAINED SEVERE THREAT...THOUGH AN ISOLATED SEVERE THUNDERSTORM OR TWO IS STILL POSSIBLE. ..EVANS/CROSBIE.. 05/23/2006  From swody1 at goshenarc.org Tue May 23 19:54:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 15:54:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231951 SWODY1 SPC AC 231949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT TUE MAY 23 2006 VALID 232000Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT ACROSS PARTS OF THE NRN AND CENTRAL PLAINS.... ...SYNOPSIS... WATER VAPOR IMAGERY SHOWS THE MID/UPPER LEVEL LOW IS NOW OVER NWRN SD/SWRN ND/SERN MT. THE LOW IS EXPECTED TO BEGIN MOVING EWD ALONG THE ND/SD BORDER THROUGH TONIGHT. LATEST SURFACE ANALYSIS SHOWS 997 LOW OVER THE MT/ND BORDER WITH A COLD FRONT THAT EXTENDS SEWD/SWD ACROSS WRN NEB AND NWRN KS INTO NERN NM. AHEAD OF THE FRONT...AIR MASS IS MOIST AND UNSTABLE WITH SURFACE DEW POINTS IN THE LOW/MID 60S AND MLCAPES BETWEEN 1000 AND 1500 J/KG. ...NRN AND CENTRAL PLAINS... AS MID/UPPER LEVEL LOW BEGINS MOVING EWD WITHIN THE NEXT FEW HOURS...LATEST RUC MODEL INDICATES AN INCREASE OF LOW LEVEL FLOW TO 40 KTS FROM NWRN OK NWD INTO SERN SD. ALSO...MID LEVEL FLOW WILL BECOME MORE WLY AT AROUND 50 KTS ENHANCING DEEP LAYER SHEAR PROFILES ACROSS ERN NEB INTO SERN SD. THIS IS REFLECTED IN THE LATEST FORECAST SOUNDINGS ACROSS THE AREA WHERE SHEAR BECOMES FAVORABLE FOR SUPERCELL STORMS. THIS ALSO COINCIDES WITH STRONG FRONTAL PUSH EWD ENHANCING UVVS ALONG THE WRN PARTS OF THE MOIST AXIS. AIR MASS IS EXPECTED TO DESTABILIZE AS ASSOCIATED MID LEVEL COLD POOL MOVES EWD OVER AREA WITH MLCAPES FORECAST TO 2000 J/KG. THUS...LARGE HAIL IS EXPECTED ALONG WITH THE POSSIBILITY OF SOME TORNADOES THIS AFTERNOON AND EARLY TONIGHT. COLD FRONT IS EXPECTED TO EXTEND SEWD/SWD THROUGH N CENTRAL SD/ERN NEB INTO CENTRAL KS BY MID EVENING WITH A LINE OF STRONG/SEVERE THUNDERSTORMS JUST AHEAD OF IT. LOW LEVEL JET IS PROJECTED TO INCREASE TO 50 KT ALONG THE NEB/IA BORDER. MODELS SHOW THAT DEEP LAYER SHEAR DECREASES FROM 40-50 KT TO 30-40 KT OVERNIGHT. THUS... MCS IS EXPECTED TO TAKE OVER TONIGHT ACROSS ERN NEB/WRN IA INTO NWRN MO WITH MAIN THREATS BEING HAIL AND DAMAGING WINDS. ..MCCARTHY.. 05/23/2006  From swody1 at goshenarc.org Wed May 24 01:02:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 23 May 2006 21:02:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240059 SWODY1 SPC AC 240057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT TUE MAY 23 2006 VALID 240100Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF NRN/CENTRAL PLAINS EWD INTO WRN MN/WRN-CENTRAL IA AND NWRN MO... ...NRN/CENTRAL PLAINS INTO NWRN MO/WRN-CENTRAL IA/SWRN MN... UPPER TROUGH...CURRENTLY LOCATED OVER THE WRN DAKOTAS...WILL BEGIN TO MAKE A MORE EWD MOVEMENT ACROSS ND/SD THE REST OF THIS FORECAST PERIOD. BAND OF 50 KT SWLY MID LEVEL WINDS ACCOMPANYING THIS STORM SYSTEM AND NOW EXTENDING FROM WRN KS ACROSS NEB TO ERN SD WILL CONTINUE TO TRANSLATE EWD ATOP SOMEWHAT NARROW/MOIST WARM SECTOR OVER THE ERN PLAINS TO WRN MN/WRN IA/WRN MO. THIS MID LEVEL FLOW COMBINED WITH STRENGTHENING NOCTURNAL SLY LLJ TO 50 KT FROM ERN KS TO ERN NEB/WRN IA WILL RESULT IN INCREASING DEEP LAYER SHEAR FOR CONTINUATION OF ORGANIZED STORMS ALONG COLD FRONT ADVANCING EWD THROUGH SD/NEB/KS OVERNIGHT. SHEAR VECTORS ORIENTED PARALLEL TO MUCH OF THE ONGOING LINE OF STORMS FROM ERN SD SWD INTO ERN NEB EXPECTED TO MAINTAIN LINEAR CONVECTIVE MODE WITH DAMAGING WINDS AND HAIL THE PRIMARY THREATS...THOUGH EMBEDDED SUPERCELLS WILL BE POSSIBLE. TORNADO POTENTIAL...EXPECTED MAINLY DURING THIS EVENING...SHOULD EXTEND FROM PARTS OF ERN NEB INTO WRN IA AND SWD INTO NERN KS WHERE LOW LEVEL DIRECTIONAL SHEAR WILL BE GREATEST ALONG INCREASING LLJ AND BENEATH SWLY FLOW ALOFT. ALSO...DEEP LAYER SHEAR INCREASING IN MAGNITUDE IS EXPECTED TO REMAIN MORE NORMAL TO THE COLD FRONT/PRE-FRONTAL DRY LINE FAVORING ADDITIONAL THREAT FOR DISCRETE STORMS. LLJ WILL BE MAINTAINED AND SHOULD VEER TO SWLY OVERNIGHT IN RESPONSE TO 60-90 METER 500 MB HEIGHT FALLS SPREADING EWD TOWARD THE UPPER MS VALLEY AHEAD OF THE UPPER TROUGH. PRIND SUGGEST UPSCALE GROWTH OF ONGOING ACTIVITY INTO AN MCS WITH STRONG WIND GUSTS AND HAIL BECOMING THE PRIMARY THREAT...WITH ACTIVITY POTENTIALLY TURNING TOWARD THE SE ACROSS IA INTO NRN MO/ERN KS. ...NWRN MN WWD THROUGH ND TO NERN MT... AIR MASS IS MODERATELY UNSTABLE ACROSS NWRN MN WWD THROUGH NRN ND INTO NERN MT. ASCENT AHEAD OF THE UPPER TROUGH IS EXPECTED TO SUPPORT ADDITIONAL THUNDERSTORMS THROUGH THE EVENING/OVERNIGHT ACROSS MAINLY ND INTO NWRN MN...WITH A DECREASING TREND OVER ERN MT. ONGOING STORMS OVER PARTS OF WEST CENTRAL MN/SERN ND AND MORE RECENT STORMS WWD ALONG VICINITY OF ND/SD BORDER WILL CONTINUE TO TRACK NNEWD INTO THE INSTABILITY AXIS SUPPORTING SOME THREAT FOR HAIL AND STRONG WIND GUSTS. ...NERN ORE/ERN WA/NRN ID... ASCENT AHEAD OF A SHORT WAVE TROUGH MOVING NNEWD ACROSS ORE/WA AT THIS TIME WILL AID IN ADDITIONAL THUNDERSTORM DEVELOPMENT THIS EVENING. STEEP LAPSE RATES...MARGINAL INSTABILITY AND 25-30 KT OF DEEP LAYER SHEAR PER 00Z RAOB AT SPOKANE SUGGESTS A CONTINUED POTENTIAL FOR AN ISOLATED SEVERE THREAT OF HAIL/STRONG WIND GUSTS. ..PETERS.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 05:58:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 01:58:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240556 SWODY1 SPC AC 240554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT WED MAY 24 2006 VALID 241200Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN IA/SRN WI/IL SWWD TO CENTRAL OK... ...SYNOPSIS... UPPER TROUGH TOPPING THE MEAN RIDGE DURING THE FIRST FEW HOURS OF THE DAY 1 FORECAST PERIOD ACROSS THE ERN DAKOTAS IS EXPECTED TO THEN TRACK SEWD OVER THE UPPER MS VALLEY/WRN GREAT LAKES REGION TODAY. PRIMARY SURFACE LOW IS PROGGED TO TRACK EWD FROM ND INTO NRN/CENTRAL MN BY THIS AFTERNOON. AT 12Z TODAY...AN OCCLUDED FRONT SHOULD EXTEND SEWD INTO WRN IA...THEN SWWD AS A COLD FRONT THROUGH ERN KS TO NWRN OK. THESE BOUNDARIES WILL MOVE EWD EXTENDING FROM THE UPPER MS VALLEY THROUGH ERN IA TO NRN MO AND THEN SWWD INTO CENTRAL OK BY 25/00Z. MEANWHILE...A QUASISTATIONARY FRONT WILL PERSIST FROM THE GULF COAST STATES NNWWD INTO THE MID MS VALLEY WHERE IT WILL INTERSECT THE COLD FRONT. ...ERN IA/SRN WI/IL SWWD THROUGH MO TO CENTRAL OK... THUNDERSTORMS SHOULD BE ONGOING AT THE START OF THE FORECAST PERIOD ACROSS PARTS OF IA/NRN MO WITHIN WAA REGIME ALONG NOSE OF SWLY LLJ. THIS ACTIVITY SHOULD SPREAD EWD INTO SRN WI/IL AND TEND TO DIMINISH IN INTENSITY AS THE LLJ WEAKENS. HOWEVER...IF STORMS PERSIST INTO THE LATE MORNING/AFTERNOON...IT IS POSSIBLE FOR THIS ACTIVITY TO INGEST INCREASINGLY HIGHER THETA-E AIR FROM THE DESTABILIZING WARM SECTOR AND INTENSIFY. SSWLY LOW LEVEL FLOW EXPECTED IN ADVANCE OF THE SURFACE FRONTS WILL ADVECT SURFACE DEWPOINTS IN THE MID 60S...NOW RESIDING ACROSS SERN PLAINS/OZARKS TO WRN IA...NEWD INTO IL/WI. SURFACE HEATING MAY BE LIMITED ACROSS PARTS OF IL/IND DUE TO ANY ONGOING THUNDERSTORMS/ ATTENDANT CLOUDINESS SPREADING ESE THROUGH THESE STATES INTO THE AFTERNOON. STRONGER SURFACE HEATING WILL BE MORE LIKELY IN THE WAKE OF THIS MORNING ACTIVITY FROM ALONG/E OF THE COLD FRONT IN CENTRAL OK/SERN KS THROUGH MO TO SWRN WI...WHERE SURFACE DEWPOINTS IN THE MIDDLE 60S WILL RESULT IN MODERATE INSTABILITY /MLCAPE UP TO 2500 J/KG/. BAND OF 40-55 KT WNWLY MID LEVEL FLOW ACCOMPANYING UPPER TROUGH WILL SPREAD ESE ACROSS THE COLD FRONT AND WARM SECTOR THIS AFTERNOON RESULTING IN 35-45 KT OF DEEP LAYER SHEAR. THUNDERSTORMS SHOULD DEVELOP ALONG THE ADVANCING FRONTS FROM WRN WI SSWWD THROUGH ERN IA BY MID-LATE AFTERNOON...WITH POTENTIAL FOR DEVELOPMENT ALSO ALONG ANY CONVECTIVE BOUNDARIES LEFT OVER BY MORNING CONVECTION IN IL/MO. MODERATE INSTABILITY COMBINED WITH INCREASING DEEP LAYER SHEAR SUPPORTS POTENTIAL FOR SUPERCELLS WITH MODELS SUGGESTING POTENTIAL FOR LINEAR STRUCTURE/SQUALL LINE DEVELOPMENT ALONG THE COLD FRONT...ESPECIALLY OVER WI INTO IL. AS ASCENT AHEAD OF THE UPPER TROUGH CONTINUES TO SPREAD SE... THUNDERSTORMS SHOULD CONTINUE TO DEVELOP SWWD ALONG THE COLD FRONT INTO NERN OK...AND EVENTUALLY CENTRAL OK AS THE SWLY LLJ STRENGTHENS. POTENTIAL EXISTS FOR STORMS TO CONTINUE THROUGH THE NIGHT SPREADING EWD INTO THE OH VALLEY AND SWD THROUGH THE OZARKS AND OK. SEVERE THREAT INTO OH VALLEY SHOULD BE MITIGATED BY EWD EXTENT OF AIR MASS DESTABILIZATION. ...ERN DAKOTAS/MUCH OF MN... THUNDERSTORMS WILL BE POSSIBLE FARTHER N ALONG THE TRACK OF THE SURFACE LOW AND ASSOCIATED WITH COLDER MID LEVEL TEMPERATURES WITH THE UPPER TROUGH. WEAK INSTABILITY/SHEAR SHOULD PRECLUDE DEVELOPMENT OF SEVERE WEATHER WITH THIS ACTIVITY. ..PETERS/JEWELL.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 12:55:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 08:55:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241252 SWODY1 SPC AC 241251 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 AM CDT WED MAY 24 2006 VALID 241300Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS ... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VLY SW INTO ERN PARTS OF THE SRN PLNS... ...SYNOPSIS... NE SD UPR LOW SHOULD CONTINUE GENERALLY E ACROSS THE UPR MS VLY THIS PERIOD AS DEEP E PACIFIC LOW EDGES SLOWLY TOWARD THE WA CST. THE SD LOW SHOULD...HOWEVER...TURN SLIGHTLY S OF E WITH TIME AS /1/ SYSTEM HAS PASSED HI PLNS RIDGE AXIS AND /2/ WNWLY JET STREAK NOW OVER THE NEB PANHANDLE WILL DRIVE STRONGEST FORCING FOR ASCENT/UPR DIVERGENCE ESEWD. AT LWR LEVELS...PACIFIC OCCLUSION/COLD FRONT ARCING S AND SW FROM DAKS/MN SURFACE LOW SHOULD PROGRESS STEADILY SE INTO THE MID MS VLY TODAY/TONIGHT. EXPECT THAT THE SRN PART OF THIS BOUNDARY WILL EDGE ONLY SLOWLY S/SE ACROSS WRN MO/KS...AND LIKELY WILL DEVOLVE INTO A WINDSHIFT LINE AS A NEW THERMAL SURGE DEVELOPS FARTHER N IN RESPONSE TO NEB JET STREAK. ELSEWHERE...WEAK N/S WARM FRONT NOW IN CNTRL/ERN MO SHOULD MOVE E/NE THROUGH THE PERIOD...REACHING CNTRL OH BY 12Z THURSDAY. ...ERN IA/SW WI/NW IL... CONVECTIVE DEBRIS ASSOCIATED WITH LAST EVENING'S SQUALL LINE SHOULD CLEAR FROM SW TO NE ACROSS WRN WI/EXTREME SE MN/ERN IA AND NW IL LATER THIS MORNING. GIVEN CURRENT LOW LEVEL MOISTURE DISTRIBUTION...AND 30-40 KT SWLY LLJ ACROSS WRN MO/IA...SETUP SHOULD ALLOW FOR CONSIDERABLE LOW LEVEL DESTABILIZATION /SBCAPE TO 2000 J PER KG/ NEWD INTO MDT RISK AREA ALONG/AHEAD OF COLD/OCCLUDED FRONT. CONVERGENCE ALONG FRONT...AND LARGE SCALE ASCENT IN EXIT REGION OF 50+ KT MID LEVEL JET STREAK...SHOULD CREATE FAVORABLE ENVIRONMENT FOR STORM INITIATION BY MID AFTERNOON OVER WRN WI. ACTIVITY SHOULD THEN DEVELOP S ALONG FRONT INTO ERN IA/NW IL. LINEAR FORCING...MODERATE TO STRONG MEAN FLOW AND DRY AIR AT MID LEVELS SUGGEST THAT STORMS WILL...SIMILAR TO THOSE IN CNTRL NEB YESTERDAY...FAIRLY QUICKLY EVOLVE INTO A FORWARD-PROPAGATING LINE PRODUCING A CORRIDOR OF HIGH WIND/HAIL. BEFORE MERGING... INDIVIDUAL STORMS MAY ALSO POSE A THREAT FOR TORNADOES GIVEN EXPECTED DEGREE OF LOW LEVEL DIRECTIONAL SHEAR AND MOISTURE /AVERAGE DEWPOINTS IN THE LOW 60S/. THE SQUALL LINE SHOULD CONTINUE E INTO THE REMAINDER OF WI AND NRN IL EARLY TONIGHT. THE STORMS SHOULD DIMINISH FAIRLY RAPIDLY GIVEN WEAKER DESTABILIZATION EXPECTED IN THESE AREAS. ...CNTRL/SRN IL WSW INTO CNTRL/SRN MO AND PARTS OF AR/OK... SURFACE HEATING AND CONVERGENCE ALONG WEAKENING FRONT/WINDSHIFT LINE SHOULD RESULT IN A SEPARATE AREA OF MORE CONCENTRATED STORMS OVER PARTS OF MO THIS AFTERNOON/EVENING...ALONG ROUGHLY THE I-70 AND I-44 CORRIDORS FROM NEAR STL TO COU/SGF. SUBSTANTIAL SBCAPE /UP TO 3000 J PER KG/ SHOULD BE PRESENT IN THIS REGION BENEATH 35-40 KT WLY MID LEVEL FLOW ON SRN FRINGE OF NEB JET. HIGH LEVEL WINDS...HOWEVER...ARE FORECAST TO REMAIN RELATIVELY WEAK /AOB 30 KTS/ AND ORIENTED ROUGHLY PARALLEL TO INITIATING BOUNDARY. STORMS/POTENTIAL SUPERCELLS WILL POSE A THREAT FOR LARGE HAIL/HIGH WIND AND PERHAPS AN ISOLATED TORNADO DURING THEIR EARLY STAGES OF DEVELOPMENT. BUT THE ACTIVITY SHOULD FAIRLY QUICKLY EVOLVE INTO ONE OR MORE ELONGATED CLUSTERS THAT...WHILE CONTAINING REMNANT EMBEDDED CIRCULATIONS...SHOULD POSE A DIMINISHING THREAT FOR HIGH-END SEVERE. THE CLUSTERS COULD EXHIBIT BOTH BACKBUILDING/ REGENERATIVE TENDENCIES SWWD INTO AR/OK...AND FORWARD PROPAGATING SEGMENTS EWD INTO IL/IND LATER TONIGHT THROUGH EARLY THURSDAY. ..CORFIDI/JEWELL.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 16:26:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 12:26:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241616 SWODY1 SPC AC 241614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT WED MAY 24 2006 VALID 241630Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF SWRN WI AND FAR ERN IA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN MS RIVER VALLEY/WRN GREAT LAKES INTO THE OZARKS... ...SYNOPSIS... COMPACT...VERTICALLY STACKED LOW OVER THE ERN DAKOTAS WILL SHIFT SLOWLY EWD TOWARD THE NRN MS RIVER VALLEY TODAY...WITH TRAILING COLD FRONT/SURFACE TROUGH ADVANCING STEADILY ESEWD INTO WRN WI/ERN IA/NRN MO. TAIL END OF THIS BOUNDARY WILL SLOW AND LIKELY STALL INTO CENTRAL OK/SERN KS/WRN MO BY LATER TODAY. STRONG HEATING AND DEEP BOUNDARY LAYER MIXING WILL TEND TO ERODE CURRENT MID/UPPER 60F SURFACE DEW POINT AXIS NOW EXTENDING FROM ERN OK INTO ERN IA. HOWEVER...INCREASING SSWLY BOUNDARY LAYER FLOW AHEAD OF THIS SYSTEM WILL LIKELY MAINTAIN AT LEAST MID/UPPER 50F SURFACE DEW POINTS NWD ACROSS THE LOWER MO AND INTO THE NRN MS RIVER VALLEYS. ...NRN MS RIVER VALLEY ACROSS ERN IA AND INTO NWRN IL/WI... STRONGEST ASCENT ALONG NOSE OF 50+ KT MID/UPPER LEVEL JET AND JUST AHEAD OF DEEP CONVERGENCE AXIS/FAST MOVING SHORTWAVE TROUGH NOW EVIDENT ON WV IMAGERY MOVING INTO SWRN MN/ERN IA WILL OVERSPREAD THE NRN MS RIVER VALLEY TODAY. THIS IS EXPECTED TO FOCUS GREATEST POTENTIAL/COVERAGE OF SEVERE THUNDERSTORMS ALONG NRN EXTENT OF MODEST LOW LEVEL MOISTURE AXIS DURING THE MID TO LATE AFTERNOON. INITIATION MAY OCCUR INTO FAR ERN MN/W-CENTRAL WI BY THE MID AFTERNOON WITH DEVELOPMENT INCREASING SSWWD INTO ERN IA/NWRN IL BY THE EARLY EVENING. MLCAPE AROUND 1000 J/KG IS ANTICIPATED INTO SWRN WI WITH CINH WEAKENING/DIMINISHING PRIOR TO 21Z. FORECAST SOUNDINGS INDICATE 35-45 KT EFFECTIVE SHEAR WILL DEVELOP ACROSS THIS REGION...WITH NEAR UNIDIRECTIONAL WIND PROFILES AND STRONG/DEEP ASCENT LIKELY SUPPORTING QUICK EVOLUTION INTO ONE OR MORE LINES OF STORMS. EMBEDDED OR PRECEEDING SUPERCELLS MAY HAVE BRIEF TORNADO POTENTIAL GIVEN MAGNITUDE OF LOW AND DEEP LAYER SHEAR. HOWEVER...SUPERCELLS WILL LIKELY BECOME OUTFLOW DOMINANT WITHIN LARGE T-TD SURFACE SPREADS/STEEP LOW LEVEL LAPSE RATES AND MAY ENHANCE BOW ECHO DEVELOPMENT WITHIN EWD MOVING LINEAR MCS. E-SEWD EXTENT OF SEVERE THREAT WILL BE LIMITED BY NARROW INSTABILITY AXIS ACROSS WI AND LOSS OF HEATING THIS EVENING. ...MO ESEWD INTO LOWER OH RIVER VALLEY AND SWWD INTO SERN KS/OK... WEAKER ASCENT SUGGESTS HEATING WILL DRIVE DEVELOPMENT SSWWD ALONG AND AHEAD OF APPROACHING SURFACE TROUGH THIS AFTERNOON ACROSS MO AND INTO PORTIONS OF SERN KS/NERN OK AND POSSIBLY INTO CENTRAL/SWRN OK. SHEAR DIMINISHES WITH SWWD EXTENT INTO THE SRN PLAINS AND RESULTANT STORMS WILL DEVELOP WEAKER ORGANIZATION SOUTHWEST OF THE OZARK PLATEAU. CONVECTIVE EVOLUTION A BIT MORE DIFFUSE ACROSS THIS REGION AS ALL THE MORNING MODELS INCREASE THUNDERSTORMS AHEAD OF SURFACE TROUGH ACROSS MUCH OF MO BY THE EARLY AFTERNOON. THOUGH SHEAR AND ASCENT WILL BE WEAKER SOUTH OF IA...AIR MASS WILL BECOME MODERATE TO STRONGLY UNSTABLE EARLY THIS AFTERNOON. SHOULD THIS DEVELOPMENT INCREASE AS CAP WEAKENS ACROSS THIS WARM SECTOR...30-40 KT OF EFFECTIVE SHEAR WILL SUPPORT ORGANIZATION INTO MULTICELL CLUSTERS/LINES WITH EMBEDDED SUPERCELLS. LARGE HAIL AND DAMAGING WINDS WILL ACCOMPANY THESE STORMS AS THEY INCREASE IN COVERAGE/INTENSITY AND SPREAD SLOWLY ESEWD THROUGH THE EVENING. AS CAP BREAKS SWWD INTO OK EARLY THIS EVENING...ISOLATED STORMS MAY PRODUCE DAMAGING WINDS GIVEN VERY STRONG HEATING. HOWEVER... SEVERE THREAT WILL BECOME MORE PULSE IN NATURE/ISOLATED WITH SWWD EXTENT. ...ERN ND AND VICINITY... RUC INDICATES SUFFICIENT HEATING LATER TODAY WITHIN RELATIVELY MOIST LOW LEVEL AIR MASS INTO NWRN MN/ERN ND WHERE SURFACE DEW POINTS ARE AROUND 60F. GIVEN COLD AIR ALOFT UNDER -12C MID LEVEL COLD POCKET AND EXPECTED 500-750 J/KG SBCAPE ACROSS THIS REGION... STORMS MAY PRODUCE HAIL AND WILL INTRODUCE LOW SEVERE PROBABILITIES INTO THE EARLY EVENING. ..EVANS/CROSBIE.. 05/24/2006  From swody1 at goshenarc.org Wed May 24 20:06:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 16:06:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 242002 SWODY1 SPC AC 242001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT WED MAY 24 2006 VALID 242000Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF SRN WI/ERN IA/NWRN IL/NERN MO... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID AND UPPER MS VALLEY INTO THE OZARKS... ...OZARKS INTO THE MID AND UPPER MO VALLEY... THUNDERSTORMS CONTINUE TO DEVELOP ACROSS WRN WI/CENTRAL AND NRN IL AND INTO PARTS OF MO AHEAD OF COLD FRONT...WHERE AIRMASS HAS BECOME MODERATELY UNSTABLE. AS UPPER LOW NOW OVER ERN ND MOVES SLOWLY SEWD...EXPECT SWLY LOW-LEVEL JET TO INCREASE BENEATH MODERATE WNWLY FLOW AT MID-LEVELS. RESULTING SHEAR WILL THUS CONTINUE TO FAVOR SEVERE STORMS/SUPERCELLS ACROSS THIS REGION. ALONG WITH THREAT FOR LARGE HAIL...DAMAGING WINDS AND A COUPLE OF TORNADOES APPEAR LIKELY AS STORM COVERAGE INCREASES. CONVECTION MAY EVOLVE INTO ONE OR MORE SEVERE MCS LATER THIS EVENING...THOUGH EWD EXTENT OF THREAT INTO INDIANA SHOULD REMAIN LIMITED DUE TO COOLER/MORE STABLE AIRMASS E OF NNW-ESE WARM FRONT NOW OVER WI/IL. ...NRN FL/FL PANHANDLE... A COUPLE OF PULSE-TYPE STORMS CAPABLE OF PRODUCING MARGINAL HAIL OR BRIEF GUSTY WINDS WILL REMAIN POSSIBLE THROUGH THIS AFTERNOON WITHIN MOIST/MARGINALLY-UNSTABLE AIRMASS INDICATED INVOF SEA-BREEZE BOUNDARY ACROSS THE FL PANHANDLE/NRN FL. THREAT SHOULD DIMINISH RAPIDLY THIS EVENING. ..GOSS.. 05/24/2006  From swody1 at goshenarc.org Thu May 25 00:46:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 24 May 2006 20:46:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250045 SWODY1 SPC AC 250044 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 PM CDT WED MAY 24 2006 VALID 250100Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH EARLY THURSDAY MORNING FROM SRN WI INTO IL/IN AND MO.... ...SYNOPSIS... MID/UPPER LEVEL LOW WILL CONTINUE TO DRIFT ESEWD FROM W CENTRAL MN INTO SWRN WI THE REMAINDER OF TONIGHT. OCCLUDED LOW OVER W CENTRAL MN HAS FRONTAL BOUNDARY EXTENDING SEWD INTO SWRN WI...THEN SWD AND SWWD THRU NWRN MO INTO THE OK PANHANDLE. CURRENT STRONG/SEVERE THUNDERSTORM ACTIVITY HAS LAID OUT SEVERAL CONVECTIVE BOUNDARIES ACROSS WRN LOWER MI INTO NRN INDIANA...AND ACROSS CENTRAL IL INTO CENTRAL MO. ...PARTS OF WI/IL/INDIANA/MO... MUCH OF THE INTENSE CONVECTION IS NOW MOVING SWD WITHIN THE LINE MAINLY GOING FOR THE BETTER MOISTURE/INSTABILITY SOURCE. THE ACTIVITY MOVING THROUGH NRN INDIANA TOWARDS OH IS WEAKENING AS IT PULLS FURTHER AWAY FROM STRONG DYNAMIC FORCING AND INTO MOISTURE STARVED AIR WITH OH HAVING DEW POINTS IN THE UPR 30S/LOWER 40S. THUS...PROBABILITIES FOR STRONG TO SEVERE THUNDERSTORMS WILL REMAIN ASSOCIATED WITH LINE OF ACTIVITY MOVING EWD INTO EAST CENTRAL AND SERN WI FOR THE NEXT HOUR OR SO UNTIL IT HITS LAKE BREEZE THAT EXTENDS FROM GRB SWD TO JUST W OF MKE AREA. AS STORMS WEAKEN ACROSS ERN WI...THERE COULD BE SOME DAMAGING WINDS AS STORMS COLLAPSE ALONG LAKE BREEZE BOUNDARY. FARTHER SOUTH...MAIN BAND OF STRONG/SEVERE THUNDERSTORMS EXTEND FROM S CENTRAL IL SWWD INTO S CENTRAL MO. AIR MASS HERE REMAINS VERY UNSTABLE WITH MLCAPE BETWEEN 1500 AND 2500 J/KG. COLD FRONT WILL CONTINUE TO PRESS EWD/SEWD ACROSS REGION AND STORMS COULD BUILD BACK TOWARDS THE SW THROUGH EARLY THURSDAY MORNING. SEVERAL BOW ECHOES ARE ALONG THIS LINE...THUS DAMAGING WINDS AND HAIL LOOK TO BE THE MAIN THREAT. LOOKS LIKE THE TORNADO THREAT IS DECREASING AS LINE MOVES AWAY FROM MAIN BAND OF MID LEVEL WINDS /45-55 KT/ AND THUS DECREASING SHEAR. ...PARTS OF W TX... STRONG/ISOLATED SEVERE THUNDERSTORMS HAVE DEVELOPED IN VICINITY OF SURFACE DRYLINE FROM SWRN OK INTO THE TX BIG BEND. STRONG DAYTIME HEATING HAS PUSHED MLCAPES TO AROUND 2000 J/KG...ENOUGH TO SUPPORT SOME HAIL...BUT ACTIVITY SHOULD DECREASE BY MID EVENING WITH LOSS OF DAYTIME HEATING. ..MCCARTHY.. 05/25/2006  From swody1 at goshenarc.org Fri May 26 06:40:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 02:40:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260638 SWODY1 SPC AC 260637 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0137 AM CDT FRI MAY 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NORTHEAST/MID ATLANTIC/SOUTHEAST/TN VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CNTRL AND NRN PLAINS/HIGH PLAINS... ...SYNOPSIS... PROGRESSIVE LARGE SCALE FLOW OF MODEST AMPLITUDE WILL CONTINUE ACROSS THE CONUS THROUGH FRIDAY AS ONE DEEP LAYER CYCLONE MOVES FROM THE GREAT LAKES TO THE NORTHEAST...AND A STRONG MID/UPPER LEVEL TROUGH EVOLVES ACROSS THE INTERIOR WEST. A MID/UPPER LEVEL RIDGE WILL SEPARATE THE TWO TROUGHS AND MOVE EAST FROM THE PLAINS TO THE MIDWEST AND DEEP SOUTH DURING THE FORECAST PERIOD. HOT AND VERY UNSTABLE CONDITIONS WILL AGAIN DEVELOP BENEATH THE RIDGE AXIS TODAY WHERE A DEEP LAYER FRONTAL ZONE WILL EXIST. EARLY TODAY...THE FRONT ORIGINATING WITH THE GREAT LAKES/NORTHEAST TROUGH...WILL EXTEND SWWD ALONG THE APPALACHIANS...THEN WWD TO THE TN VALLEY...AND NWWD INTO THE PLAINS. CONVECTIVELY ENHANCED COLD POOLS/OUTFLOW WILL LOCALLY REINFORCE THE FRONTAL ZONE FROM THE APPALACHIANS TO THE PLAINS. AS ERN TROUGH MOVES ACROSS THE NORTHEAST AND MID ATLANTIC... ASSOCIATED COLD FRONT WILL DEVELOP EAST ACROSS THE APPALACHIANS AND THEN MOVE OFF THE ATLANTIC COAST THROUGH THE PERIOD. THE BOUNDARY WILL LIKELY BECOME QUASI-STATIONARY FROM THE SRN APPALACHIANS/TN VALLEY TO THE LOWER MO VALLEY. AS WRN U.S. TROUGH SPREADS EAST AND LOW LEVEL SLY FLOW INCREASES ACROSS THE PLAINS...THE FRONTAL ZONE OVER THE PLAINS SHOULD REDEVELOP NWD FROM KS TO THE CNTRL/NRN PLAINS...AS LEE TROUGH STRENGTHENS ACROSS THE HIGH PLAINS. ...NORTHEAST/MID ATLANTIC... STRONG DYNAMIC FORCING/HEIGHT FALLS WITH THE UPPER TROUGH WILL ACT ON INCREASING INSTABILITY TO AT LEAST MAINTAIN...AND POSSIBLY ENHANCE...CONVECTIVE LINE MOVING EAST THROUGH THE AFTERNOON. STRENGTHENING DEEP LAYER FLOW COINCIDENT WITH THE INCREASING INSTABILITY SHOULD SUPPORT FAST MOVING LINE SEGMENTS WITH DAMAGING WINDS AND PERHAPS SOME HAIL FROM THE LOWER HUDSON VALLEY SWD ACROSS ERN PA AND NJ. FROM DELMARVA AREA SWD ACROSS THE VA/NC CAPES...GREATER MOISTURE AND LATER ARRIVAL OF FORCING ASSOCIATED WITH THE WITH THE UPPER TROUGH WILL ALLOW FOR GREATER DESTABILIZATION THESE AREAS. SHEAR WILL INITIALLY BE LIMITED BUT SHOULD INCREASE AS STORMS DEVELOP ON STRENGTHENING LEE TROUGH THROUGH LATE AFTERNOON. POTENTIAL FOR MORE DISCRETE CONVECTION... AT LEAST INITIALLY...AND POSSIBLE SEA/BAY/SOUND BREEZE INTERACTIONS MAY RESULT IN SLIGHTLY GREATER SUPERCELL/LARGE HAIL THREAT...IN ADDITION TO DAMAGING WINDS FROM POSSIBLE EVOLUTION INTO CONVECTIVE LINE. ...NRN/CNTRL PLAINS... INCREASINGLY STRONG SWLY FLOW ALOFT AND GRADUALLY FALLING HEIGHTS WILL STRENGTHEN LEE-TROUGHING ACROSS THE NRN AND CNTRL HIGH PLAINS TODAY. A NUMBER OF LOW AMPLITUDE DISTURBANCES ROTATING NEWD OUT OF THE LARGER SCALE WRN TROUGH ARE SUGGESTED BY MODEL GUIDANCE AND WILL AID CONVECTIVE INITIATION ACROSS THE HIGHER TERRAIN. LOW LEVEL UPSLOPE FLOW AND MOISTURE ADVECTION APPEAR TO BE GREATEST FROM NERN CO NWD ACROSS THE WRN DAKOTAS THROUGH LATE EVENING. LEE-SIDE SURFACE LOWS MAY FURTHER FOCUS CONVECTIVE DEVELOPMENT WITH ACTIVITY MOVING EWD/NEWD INTO STRONGER INSTABILITY EAST OF THE LEE TROUGH/DRYLINE. SEVERAL CLUSTERS OF STORMS/SUPERCELLS APPEAR LIKELY. LARGE HAIL AND HIGH WINDS SHOULD ACCOMPANY THIS ACTIVITY AS IT SPREADS GENERALLY NEWD THROUGH LATE EVENING WITH SOME POTENTIAL FOR ISOLATED TORNADOES NEAR ANY SURFACE LOW AND/OR LEE TROUGH/RETREATING WARM FRONT INTERSECTION. AN MCS OR TWO MAY EVOLVE THROUGH THE LATE EVENING...ESPECIALLY NEAR THE RETREATING WARM FRONT OVER NEB...AND PERHAPS ACROSS ND WHERE GUIDANCE DEPICTS STRONGER QG FORCING FOR ASCENT WILL PERSIST INTO EARLY SATURDAY. ...HIGH PLAINS SERN CO SOUTH TO BIG BEND... LEE TROUGH/DRYLINE WILL ALSO SPUR GENERALLY HIGH-BASED TSTM DEVELOPMENT FROM SERN CO SWD TO THE RIO GRANDE BY AFTERNOON. WEAKER LARGE SCALE FORCING FOR ASCENT ACROSS THESE AREAS SUGGESTS MORE ISOLATED DEVELOPMENT. NONETHELESS...VERY HOT BOUNDARY LAYER AND SUFFICIENT EFFECTIVE SHEAR WILL SUPPORT VIGOROUS SUPERCELL STORMS WITH AT LEAST A LOW PROBABILITY THREAT OF LARGE HAIL AND DAMAGING DOWNBURST WINDS. ...TN VALLEY ACROSS MID MS VALLEY AND LOWER MO VALLEY... STRONG TO EXTREME INSTABILITY WILL DEVELOP ALONG THE STALLED FRONTAL ZONE...BUT BENEATH RIDGING ALOFT AND STOUT CAPPING INVERSION. THERE IS FURTHER UNCERTAINTY REGARDING AFTERNOON TSTM DEVELOPMENT ACROSS PARTS OF THE REGION GIVEN ONGOING MCS ACTIVITY ACROSS KS AND SWRN MO. FAVORABLE ORIENTATION/FORCING FROM MCS OUTFLOWS AND RESIDUAL FRONT...COUPLED WITH LOCALLY INTENSE HEATING/DESTABILIZATION FROM TN SEWD ACROSS SC SHOULD OVERCOME CAP THESE AREAS TO RESULT IN POTENTIALLY EXPLOSIVE CONVECTIVE DEVELOPMENT. LARGE HAIL AND LOCALLY DAMAGING WINDS APPEAR POSSIBLE DURING THE DAY FROM THIS CONVECTION. HOWEVER...FROM THE MS RIVER NWWD ACROSS MO...GENERALLY WEAKER SHEAR AND FORCING BENEATH MID LEVEL RIDGE...AND CURRENT UNCERTAINTIES REGARDING MCS EVOLUTION...PRECLUDE HIGHER PROBABILITY SEVERE WEATHER FORECAST OVER THIS REGION AT THIS TIME. ...SOUTH FL... LATEST GUIDANCE INDICATED THAT DIURNAL TSTM DEVELOPMENT MAY COINCIDE WITH THE ARRIVAL OF SLIGHTLY STRONGER WLY MID LEVEL FLOW ACROSS SRN FL. STORMS DEVELOPING ON EAST COAST SEA BREEZE...AND ACROSS THE KEYS...MAY PERSIST OR BECOME BETTER ORGANIZED TO PRODUCE AN ISOLATED TORNADO...OR A COUPLE OF HAIL/WIND EVENTS. OVERALL POTENTIAL DOES NOT APPEAR TO SUPPORT HIGHER PROBABILITIES AT THIS TIME. ..CARBIN/JEWELL.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 13:09:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 09:09:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261308 SWODY1 SPC AC 261306 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 AM CDT FRI MAY 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN/CENTRAL PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC REGION INTO THE APPALACHIANS AND TN VALLEY/MID SOUTH... ...SYNOPSIS... UPPER LOW OVER THE GREAT LAKES IS FORECAST TO CONTINUE EWD TODAY ACROSS THE LOWER LAKES...OPENING INTO A TROUGH TONIGHT AS IT MOVES TOWARD THE ATLANTIC COAST. WATER VAPOR IMAGERY INDICATES THE UPSTREAM FLOW PATTERN IS BEGINNING TO AMPLIFY PER MODEL FORECASTS WITH A RIDGE BEGINNING TO BUILD OVER THE PLAINS AS TROUGH DEEPENS ALONG THE PACIFIC COAST. THESE SYSTEMS WILL PROGRESS EWD THROUGH THE PERIOD WITH THE RIDGE REACHING THE MS VALLEY WHILE THE TROUGH SETTLES OVER THE PACIFIC NORTHWEST BY 27/12Z. AT THE SURFACE...A LOW OVER LOWER MI IS EXPECTED TO MOVE EWD INTO NY THIS AFTERNOON AND ACROSS NEW ENGLAND TONIGHT. COLD FRONT TRAILING SWWD FROM THE LOW WILL MOVE ACROSS THE APPALACHIANS TOWARD THE MID ATLANTIC COAST...CONTINUING WWD AS A STATIONARY FRONT THROUGH THE TN VALLEY...THEN LIFTING NWD AS A WARM FRONT INTO THE MO RIVER VALLEY AS A LOW MOVES INTO THE NRN HIGH PLAINS TONIGHT. A SERIES OF CONVECTIVE OUTFLOW BOUNDARIES ARE LOCATED AHEAD OF THE FRONT FROM VA WWD INTO THE TN VALLEY AND CENTRAL PLAINS...AND THESE MAY PROVIDE ADDITIONAL FOCI FOR REDEVELOPMENT OF THUNDERSTORMS LATER TODAY. LASTLY...A NORTH-SOUTH DRY LINE IS EXPECTED TO BECOME BETTER ESTABLISHED THIS AFTERNOON ACROSS THE CENTRAL/SRN HIGH PLAINS. ...MID ATLANTIC STATES INTO CAROLINAS AND SRN APPALACHIANS... DYNAMIC FORCING FOR LARGE SCALE ASCENT ASSOCIATED WITH GREAT LAKES UPPER LOW IS EXPECTED TO SPREAD EWD ACROSS THIS REGION TODAY...ENHANCED BY MESOSCALE CONVERGENCE ALONG SURFACE TROUGH EXPECTED TO DEVELOP IN THE LEE OF THE APPALACHIANS. EARLY VISIBLE IMAGERY SHOWS CLEAR SKIES FROM THE DELMARVA ACROSS SERN VA INTO MUCH OF THE CAROLINAS. ALTHOUGH SOME CLOUDS ARE SPREADING EWD ACROSS THE APPALACHIANS BREAKS IN THE CLOUD COVER ARE LIKELY TO OCCUR. THIS WILL ALLOW STRONGER DIURNAL HEATING ACROSS PARTS OF THIS REGION TODAY WHERE DEW POINTS ARE EXPECTED TO INCREASE INTO THE 65-70F RANGE. 12Z REGIONAL SOUNDINGS EXHIBIT MODERATE STEEP LAPSE RATES WHICH WILL INCREASE MAGNITUDE OF INSTABILITY THIS AFTERNOON /MLCAPE OF 1500-2000 J/KG/. SEVERAL BANDS OF THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE LEE TROUGH EAST OF THE APPALACHIANS...AND ALONG/AHEAD OF THE COLD FRONT OVER WV/WRN VA/WRN PA REGION AS UPPER SYSTEM MOVES ACROSS THE AREA DURING THE AFTERNOON. STRONGEST DEEP LAYER SHEAR OF 30-35 KT IS EXPECTED ACROSS THE CAROLINAS NWD INTO THE DELMARVA REGION WHICH WILL ENHANCE STORM ORGANIZATION AND INTENSITY. A FEW SEVERE THUNDERSTORMS WILL BE POSSIBLE MAINLY THIS AFTERNOON AND EVENING WITH PRIMARY THREAT FOR DAMAGING WINDS AND LARGE HAIL. ADDITIONAL SEVERE STORMS MAY DEVELOP WWD INTO PARTS OF GA AND AL ALONG REMNANTS OF OUTFLOW BOUNDARIES ALONG SRN EDGE OF UPPER TROUGH WHERE UNSTABLE ENVIRONMENT (MLCAPE OF 2000-3000 J/KG) WILL BE LOCATED. ...MID SOUTH REGION... ANIMATED RADAR IMAGERY SUGGESTS MCS MOVING ACROSS SERN KS/NERN OK HAS GENERATED AN MCV. THIS FEATURE MAY CONTINUE MOVING SEWD TOWARD AR TODAY...WHERE 12Z LZK SOUNDING SHOWS VERY STEEP LAPSE RATE IN THE 800-550 MB LAYER. THE CAP IS EXPECTED TO GRADUALLY WEAKEN AS LOW LEVEL HEATING COUPLES WITH POSSIBLE ASCENT ASSOCIATED WITH THE UPSTREAM MCV...WITH POTENTIAL FOR THUNDERSTORMS TO REDEVELOP THIS AFTERNOON. STRONG INSTABILITY WITH MLCAPE OF 2000-3000 J/KG SUGGESTS THREAT FOR SEVERE THUNDERSTORMS ACROSS THIS AREA. ...CENTRAL/NRN PLAINS... ONGOING ELEVATED THUNDERSTORMS FROM SOUTH CENTRAL NEB INTO PARTS OF KS ARE EXPECTED TO CONTINUE MOVING EWD/ESEWD THIS MORNING. STRONGER CELLS IN KS MAY HAVE POTENTIAL TO PRODUCE HAIL. OTHER SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP LATER THIS AFTERNOON AND EVENING OVER THE HIGH PLAINS FROM NERN CO NWD ACROSS WRN PARTS OF THE DAKOTAS AND ERN MT...AS WEAK PERTURBATIONS WITHIN STRENGTHENING SWLY FLOW ALOFT MOVE ACROSS WRN EDGE OF LOW LEVEL MOISTURE FIELD. 12Z SOUNDINGS SHOW STEEP MID LEVEL LAPSE RATES IN PLACE...AND CLEAR SKIES WILL PROMOTE STRONG INSOLATION WHICH WILL CONTRIBUTE TO DESTABILIZATION. DEEP LAYER SHEAR WILL BE THE STRONGEST OVER THE NRN HIGH PLAINS REGION WITH 40-50 KT IN THE LOWEST 6 KM...WITH SHEAR OF 30-35 KT EXTENDING SWD INTO THE CENTRAL PLAINS. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE HIGH PLAINS AND MOVE NEWD LATE THIS AFTERNOON AND EVENING...WITH SOME OF THE ACTIVITY LIKELY PERSISTING INTO THE OVERNIGHT HOURS AS THE LOW LEVEL JET INTENSIFIES AFTER DARK. ...SRN HIGH PLAINS... VERY UNSTABLE ENVIRONMENT IS EVIDENT IN 12Z SOUNDINGS AT AMA AND MAF WITH NEARLY DRY ADIABATIC LAPSE RATES PRESENT ABOVE THE PBL. THIS WILL CONTRIBUTE TO STRONGLY UNSTABLE ENVIRONMENT EAST OF THE DRY LINE WHERE MLCAPE OF 2000-3000 J/KG IS EXPECTED. FORCING FOR LARGE SCALE ASCENT WILL BE MINIMAL AS THE UPPER RIDGE MOVES OVER THE AREA AND DRY LINE CONVERGENCE IS ALSO EXPECTED TO BE WEAK SUGGESTING THUNDERSTORM ACTIVITY WILL BE ISOLATED AT BEST. HOWEVER...THE 06Z ETA AND NAM-WRF PARALLEL AND THE 00Z EXPERIMENTAL HIGH RESOLUTION WRF-NMM ALL DEVELOP CONVECTION OVER PARTS OF WRN TX LATE THIS AFTERNOON/EVENING. GIVEN THE WEAK SHEAR A FEW PULSE STORMS OR MULTICELL CLUSTERS MAY DEVELOP WITH POTENTIAL FOR ISOLATED LARGE HAIL/DOWNBURSTS. ...SRN FL... WILL MAINTAIN LOW PROBABILITY FOR SEVERE STORMS ACROSS THIS AREA TODAY AS STRONGER BRANCH OF MID LEVEL FLOW IS FORECAST OVER THE AREA...ENHANCING DEEP LAYER SHEAR. PRIMARY THREAT IS EXPECTED OVER THE INTERIOR AND EAST COAST OF SOUTH FL AS STORMS PROGRESS EWD TOWARD EAST COAST SEA BREEZE FRONT. ..WEISS/JEWELL.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 16:41:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 12:41:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261631 SWODY1 SPC AC 261630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT FRI MAY 26 2006 VALID 261630Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NORTHERN AR...ACROSS THE TN VALLEY...INTO THE MID ATLANTIC AND SOUTHERN NEW ENGLAND STATES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CENTRAL AND NORTHERN PLAINS... ...SOUTHERN NEW ENGLAND INTO CAROLINAS... STRONG UPPER TROUGH WILL CONTINUE TO ROTATE EASTWARD INTO NY AND NEW ENGLAND TODAY...WITH BAND OF 40-50 KNOT WESTERLY FLOW EXTENDING ACROSS THE SOUTHERN APPALACHIANS AND CAROLINAS. VISIBLE SATELLITE IMAGERY SHOWS A LARGE AREA OF CLOUDINESS BENEATH UPPER SYSTEM ACROSS MUCH OF THE GREAT LAKES REGION AND OH VALLEY. HOWEVER...STRONG HEATING IS EXPECTED AHEAD OF LEADING EDGE OF CLOUDS ACROSS SOUTHERN NEW ENGLAND...AND OVER PARTS OF SOUTHEAST VA AND MUCH OF NC. THIS AREA IS LIKELY TO DESTABILIZE THROUGH THE EARLY AFTERNOON WITH MLCAPE VALUES OF AROUND 500 J/KG OVER NEW ENGLAND...AND 1000-2000 J/KG OVER VA/NC. SCATTERED THUNDERSTORMS ARE LIKELY TO DEVELOP OVER THIS AREA...WITH A THREAT OF DAMAGING WINDS AND HAIL IN STRONGER CELLS. POTENTIAL FOR ORGANIZED SEVERE STORMS OVER SOUTHERN NEW ENGLAND WILL BE MITIGATED BY LESS LOW LEVEL MOISTURE AND ONSHORE FLOW. ...AR/TN/MS/AL/GA... REMNANT OUTFLOW BOUNDARIES FROM OVERNIGHT CONVECTION EXTEND FROM STORMS OVER KS...ACROSS PARTS OF AR/TN INTO MS/AL/GA. BOUNDARIES ARE WEAKENING RAPIDLY THIS AFTERNOON...BUT MAY BECOME THE FOCUS FOR SCATTERED THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING. AMPLE MOISTURE AND MODERATELY/VERY UNSTABLE AIR MASS SUGGEST A THREAT OF HAIL AND DAMAGING WINDS IN STRONGER CELLS. UPPER RIDGE WILL BEGIN TO BUILD INTO WESTERN PARTS OF AREA AFTER 00Z...LIKELY DIMINISHING THREAT. ...NORTHERN/CENTRAL PLAINS... BROAD ZONE OF MODERATE SOUTHWESTERLY MID LEVEL FLOW IS PRESENT FROM KS INTO ND TODAY. STRONG DAYTIME HEATING WILL RESULT IN AFTERNOON TEMPERATURES IN THE 90S AND STEEP LOW/MID LEVEL LAPSE RATES THROUGHOUT THE REGION. DEEP MIXING IS EXPECTED TO RESULT IN SCATTERED THUNDERSTORM DEVELOPMENT BY LATE AFTERNOON ALONG WEST EDGE OF LOW LEVEL INSTABILITY ACROSS EASTERN WY. ACTIVITY IS FORECAST TO SPREAD EASTWARD INTO THE DAKOTAS/NEB/KS THROUGH THE EVENING. DAMAGING WINDS AND HAIL WILL BE THE MAIN THREATS. STRONGER LOW LEVEL BAROCLINIC ZONE IS FORECAST TO LIE ACROSS PARTS OF WESTERN NEB AND NORTHERN KS...WHERE ISOLATED SUPERCELLS AND PERHAPS TORNADOES MAY ALSO OCCUR. ...EASTERN MT... MODELS SUGGEST THAT MAIN SURFACE LOW WILL MOVE FROM EASTERN WY INTO ND THIS EVENING. NORTHEASTERLY UPSLOPE FLOW WILL RESULT ACROSS EASTERN AND SOUTH CENTRAL MT. SURFACE DEWPOINTS IN THE LOWER 50S AND FULL SUNSHINE MOST OF THE DAY WILL AID IN THE DEVELOPMENT OF MODERATE INSTABILITY AND SCATTERED EVENING STORMS. FORECAST SOUNDINGS SHOW SIGNIFICANT LOW LEVEL AND DEEP LAYER SHEAR ...FAVORABLE FOR SUPERCELLS CAPABLE OF LARGE HAIL. ...OH/PA/WV... BREAKS IN THE CLOUDS AND POCKET OF COOLER MID LEVEL TEMPERATURES WILL SUPPORT DEVELOPMENT OF SCATTERED THUNDERSTORMS THIS AFTERNOON. HAIL MAY OCCUR IN STRONGER CELLS BEFORE ACTIVITY WEAKENS THIS EVENING. ...SOUTH FL... VERY MOIST AND MODERATELY UNSTABLE AIR MASS IS PRESENT TODAY OVER SOUTH FL...BENEATH BRANCH OF STRONGER WESTERLY MID/UPPER LEVEL FLOW. CLOUDINESS SHOULD LIMIT DAYTIME HEATING IN THIS REGION. HOWEVER...CONDITIONAL THREAT WILL EXIST WITH ANY STORMS THAT CAN DEVELOP ACROSS AREA. LOCALLY DAMAGING WINDS WOULD LIKELY BE THE MAIN THREAT. ...SOUTHERN HIGH PLAINS... WATER VAPOR IMAGERY SHOWS A WEAK UPPER VORT MAX MOVING EASTWARD ACROSS WESTERN NM. THIS FEATURE WILL APPROACH THE SOUTHERN HIGH PLAINS THIS AFTERNOON AND EVENING NEAR TIME OF PEAK HEATING. SCATTERED THUNDERSTORMS MAY DEVELOP ALONG WEST EDGE OF STRONGER MOISTURE/INSTABILITY OVER WEST TX. WEAK VERTICAL SHEAR SHOULD LIMIT AREAL COVERAGE AND INTENSITY OF STORMS. ..HART/TAYLOR.. 05/26/2006  From swody1 at goshenarc.org Fri May 26 19:47:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 15:47:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261944 SWODY1 SPC AC 261943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT FRI MAY 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-ATLANTIC/CAROLINAS WWD INTO THE MID-SOUTH... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL/NRN PLAINS... ...ERN STATES... WATER VAPOR IMAGERY SHOWS THE UPPER LOW ROTATING EWD INTO THE UPPER OH VLY THIS AFTN. MODEST H5 JET WRAPPING EWD BENEATH THE LOW WAS ENHANCING LARGE SCALE ASCENT ACROSS THE CAROLINAS. STRONG-SEVERE TSTMS HAVE BEEN FAVORING THE SEA-BREEZE AND LEE-TROUGH FROM SCNTRL VA SWD INTO THE CAROLINAS...ENHANCED BY THE LARGE SCALE LIFT. STRONG HEATING HAS CONTRIBUTED TO MLCAPES FROM 2000-3000 J/KG AND WILL BE SUPPORTIVE FOR VIGOROUS UPDRAFTS. THIRTY-40 KTS OF MEAN FLOW IN WELL-MIXED BOUNDARY LAYER WILL ENCOURAGE LARGE HAIL AND DAMAGING WINDS...ESPECIALLY FROM SERN VA INTO THE ERN CAROLINAS THROUGH THIS EVENING. MEANWHILE...RESIDUAL BOUNDARY LAYER MSTR BENEATH MINUS 12 DEGREE C H5 TEMPERATURES ASSOCD WITH THE UPPER LOW HAS BEEN FAVORABLE FOR SCT TSTMS FROM THE KY COALFIELDS NWD INTO THE UPPER OH VLY. SOME OF THESE TSTMS MAY ADVANCE EAST OF THE ALLEGHENY PLATEAU AND/OR DEVELOP ACROSS THE FOOTHILLS IN VA/MD THROUGH THE AFTN. ACTIVITY SHOULD BE LARGELY DIURNAL AND STRONGER UPDRAFTS WILL CONTAIN LARGE HAIL AND GUSTY WINDS. FARTHER N...CLOUDS AND PCPN HAVE UNDERMINED STRONG BOUNDARY LAYER DESTABILIZATION THIS AFTN THROUGHOUT CNTRL/ERN PA NEWD INTO SRN NEW ENGLAND. THIS COMBINED WITH POOR MID-TROP LAPSE RATES SUGGESTS THAT WIDESPREAD SEVERE WEATHER IS NOT LIKELY. ...NRN PLAINS... SFC LOW APPEARS TO BE CONSOLIDATING ACROSS CNTRL WY AT 19Z WITH BOUNDARY LAYER FLOW BACKING TO A MORE UPSLOPE COMPONENT IN NERN WY AND SCNTRL MT. THIS LOW-LEVEL TRAJECTORY SHOULD ADVECT 50S SFC DEW POINTS SWWD AND BE FAVORABLE FOR INCREASING MOUNTAIN TSTMS LATER THIS AFTERNOON. ACTIVITY SHOULD MOVE AND/OR DEVELOP NEWD ALONG/N OF THE BAROCLINIC ZONE INTO PARTS OF ND OVERNIGHT...ALONG SERN PERIPHERY OF THE UPSTREAM UPPER TROUGH. FAVORABLE VERTICAL SHEAR AND LAPSE RATES WILL EXIST FOR SUPERCELLS EVOLVING INTO LINE SEGMENTS CAPABLE OF MAINLY LARGE HAIL. ...CNTRL PLAINS... WATER VAPOR SHOWS A WEAK VORT MAX ROTATING NEWD THROUGH NCNTRL NM AND SCNTRL CO THIS AFTN. THIS HAS LIKELY ENHANCED THE DIURNAL UPSLOPE ACROSS THE CO/WY FRONT RANGE...MAINTAINING MODEST BOUNDARY LAYER MSTR TO THE MOUNTAINS. HEATING...UPSLOPE FLOW AND LARGE SCALE ASCENT WILL BE FAVORABLE FOR UPSCALE GROWTH OF MOUNTAIN TSTMS THROUGH THE EVENING AS THEY MOVE ONTO THE PLAINS. VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS...PRIMARILY EARLY IN THE TSTM LIFE-CYCLES WITH LARGE HAIL AND PERHAPS A TORNADO OR TWO. EVOLUTION INTO AN MCS IS LIKELY OVERNIGHT FROM NERN CO/SERN WY ACROSS NEB AND SRN SD. HERE...THE LLJ AXIS IS EXPECTED TO IMPINGE ON A NW-SE ORIENTED WARM FRONT...MAXIMIZING LOW/MID-LEVEL WARM ADVECTION. LARGE HAIL MAY ACCOMPANY THE STRONGER STORMS OWING TO THE STEEP MID-TROPOSPHERIC LAPSE RATES. ...SRN HIGH PLAINS... A PATCH OF MID-LEVEL MSTR WAS EVIDENT ACROSS THE TX HIGH PLAINS ON SATL IMAGERY. GIVEN VERY HOT BOUNDARY LAYER TEMPERATURES AND LOW-LEVEL CONVERGENCE ALONG THE DRYLINE/LEE-TROUGH...CINH SHOULD ERODE SUFFICIENTLY FOR THE POTENTIAL FOR TSTMS WITHIN THE MID-CLOUD LATER THIS AFTN. VERTICAL SHEAR 30-40 KTS WILL BE FAVORABLE FOR SUPERCELLS AND WELL-MIXED BOUNDARY LAYER WILL ENCOURAGE MICROBURSTS. COVERAGE SHOULD REMAIN ISOLD. ...CNTRL/SRN FL... WEAK SEABREEZE WAS THE FOCUS FOR TSTM INITIATION ACROSS CNTRL/SRN FL EARLY THIS AFTN. THROUGH THE REMAINDER OF PEAK HEATING... LOCALIZED OUTFLOW BOUNDARIES WILL BE IMPETUS FOR NEW UPDRAFTS. MAIN THREAT WILL BE HEAVY RAIN...THOUGH MODEST MID-LEVEL LAPSE RATES WILL FAVOR MARGINALLY SEVERE HAIL. ACTIVITY WILL DIMINISH AFTER SUNDOWN. ..RACY.. 05/26/2006  From swody1 at goshenarc.org Sat May 27 01:07:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 26 May 2006 21:07:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270106 SWODY1 SPC AC 270105 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT FRI MAY 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL AND NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE TN VALLEY...MID MS VALLEY...SRN APPALACHIANS...CAROLINAS AND VA... ...CNTRL AND NRN PLAINS... WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A SOUTHWEST FLOW PATTERN OVER THE NCNTRL US WITH SEVERAL MINOR SHORTWAVE TROUGHS EMBEDDED IN THE FLOW. SEVERAL MCS CLUSTERS ARE DEVELOPING ON THE WRN EDGE OF AN AXIS OF MODERATE INSTABILITY LOCATED FROM SRN NEB EXTENDING NWD INTO THE WCNTRL DAKOTAS. AS THE CONVECTION MOVES NEWD INTO INCREASING INSTABILITY...STORM COVERAGE SHOULD EXPAND DUE TO THE WIDESPREAD LARGE-SCALE ASCENT AND INCREASING LOW-LEVEL JET LATE THIS EVENING. AS A RESULT...A COUPLE OF OVERNIGHT MCS CLUSTERS SHOULD DEVELOP WITH ONE MCS LIKELY NEAR A LOW-LEVEL JET MAX IN ND AND ANOTHER LIKELY IN THE NOSE OF A SECONDARY LOW-LEVEL JET MAX IN CNTRL AND ERN NEB. FORECAST SOUNDINGS ACROSS THE CNTRL AND NRN PLAINS THIS EVENING SHOW MODERATE VERTICAL SHEAR PROFILES IN PLACE DUE TO STRONG DIRECTIONAL SHEAR. AS LOW-LEVEL FLOW INCREASES OVERNIGHT...THE VERTICAL SHEAR SHOULD BECOME ENHANCED WITH A CONTINUED THREAT OF SUPERCELLS. A FEW TORNADOES WILL BE POSSIBLE ESPECIALLY ACROSS NEB ON THE NOSE OF A 45 KT LOW-LEVEL JET WHICH IS FORECAST TO ENHANCE THE LOW-LEVEL SHEAR OVERNIGHT. IN ADDITION...STEEP LAPSE RATES WILL ALSO MAKE LARGE HAIL LIKELY WITH SUPERCELLS THAT PERSIST. THE WIND DAMAGE POTENTIAL MAY ALSO INCREASE AS CELLS MERGE AND MCS DEVELOPMENT OCCURS ACROSS THE REGION OVERNIGHT. ...MID MS AND TN VALLEYS/SRN APPALACHIANS/CAROLINAS... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LEVEL TROUGH LOCATED ALONG THE ERN SEABOARD. AT THE SFC...A COLD FRONT IS LOCATED ACROSS THE SRN APPALACHIAN MTNS AND A MODERATELY UNSTABLE AIRMASS EXISTS AHEAD OF THE FRONT. STORMS SHOULD REMAIN SUSTAINED LATE THIS EVENING ACROSS THE WARM SECTOR DUE TO WIDESPREAD LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-TROUGH. THE GREATEST COVERAGE OF STORMS SHOULD BE IN THE ERN CAROLINAS AS A 40-45 LOW-LEVEL JET EXPANDS LATE THIS EVENING. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES WHICH COMBINED WITH THE INSTABILITY SHOULD CONTINUE TO BE FAVORABLE FOR SUPERCELLS. STEEP LAPSE RATES SHOWN ON FORECAST SOUNDINGS SUGGEST LARGE HAIL AND WIND DAMAGE WILL BE LIKELY WITH THE STRONGER CELLS LATE THIS EVENING. HOWEVER...THE SEVERE THREAT SHOULD DECREASE AFTER MIDNIGHT AS INSTABILITY WEAKENS ACROSS THE REGION. ..BROYLES.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 06:03:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 02:03:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270602 SWODY1 SPC AC 270600 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT SAT MAY 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...NRN PLAINS... AN UPPER-LOW AND ASSOCIATED TROUGH WILL DRIFT EWD INTO THE NRN ROCKIES AND FOUR CORNERS REGION THROUGH SATURDAY. SWLY FLOW WILL REMAIN IN PLACE ACROSS THE NRN PLAINS AS MID-LEVEL FLOW GRADUALLY STRENGTHENS ACROSS THE REGION. AHEAD OF THE TROUGH...WIDESPREAD LARGE-SCALE ASCENT WILL SUPPORT THUNDERSTORM DEVELOPMENT SATURDAY AFTERNOON NEAR A SFC LOW AND FRONTAL BOUNDARY EXTENDING ENEWD ACROSS NRN ND. SFC DEWPOINTS NEAR 60 F SHOULD RESULT IN STRONG INSTABILITY ALONG AND SOUTH OF THE BOUNDARY. AS STORMS ORGANIZE AND MOVE EWD ALONG THE GRADIENT IN INSTABILITY...MCS DEVELOPMENT APPEARS LIKELY BY SATURDAY EVENING ACROSS NRN AND ERN ND INTO NRN MN. FORECAST SOUNDINGS ACROSS THE REGION LATE SATURDAY AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES WITH STEEP MID-LEVEL LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. BECAUSE OF THE VERY UNSTABLE AIRMASS...VERY LARGE HAIL WILL ALSO BE POSSIBLE WITH THE STRONGER SUPERCELLS. IN ADDITION...A FEW TORNADOES MAY OCCUR WITH SUPERCELLS THAT PARALLEL THE BOUNDARY AS AN IMPRESSIVE 45-55 KT LOW-LEVEL JET STRENGTHENS IN THE LATE AFTERNOON AND EARLY EVENING. A STRONG TORNADO REMAINS POSSIBLE NORTHEAST OF THE SFC LOW ESPECIALLY IF STORMS REMAIN DISCRETE AND SFC DEWPOINTS REACH THE LOWER 60S F ACROSS NERN ND BY LATE AFTERNOON. IF STORMS DEVELOP INTO A LINEAR ORIENTATION...THEN THE WIND DAMAGE THREAT WOULD ALSO BE ENHANCED IN THE EVENING. AN ISOLATED SEVERE THREAT MAY CONTINUE OVERNIGHT AS THE MCS TRACKS EWD ACROSS NRN MN CONSIDERING THE AMOUNT OF INSTABILITY FORECAST ACROSS THE REGION. ...SRN PLAINS... SOUTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE SRN PLAINS THROUGH SATURDAY. AT THE SFC...A TROUGH IS FORECAST TO BE LOCATED ACROSS WRN KS AND WEST TX WITH DEWPOINTS EAST OF THE TROUGH IN THE 60S F. THIS SHOULD RESULT IN MODERATE TO STRONG INSTABILITY BY LATE AFTERNOON EAST OF THE TROUGH. A CAPPING INVERSION SHOULD WEAKEN ENOUGH BY LATE AFTERNOON FOR THE INITIATION OF A FEW ISOLATED STORMS ACROSS WRN KS...WRN OK...THE ERN TX PANHANDLE AND WCNTRL TX. ALTHOUGH FORECAST SOUNDINGS SHOW 0-6 KM SHEAR VALUES GENERALLY BELOW 3O KT...THE STEEP LAPSE RATES AND AMOUNT OF INSTABILITY MAY BE ENOUGH FOR A FEW MARGINALLY SEVERE STORMS IN THE LATE AFTERNOON OR EARLY EVENING. ...SERN STATES... AN UPPER-LEVEL RIDGE WILL BE IN PLACE ACROSS THE OH AND TN VALLEYS THROUGH SATURDAY. AT THE SFC...A BOUNDARY IS FORECAST TO BE IN PLACE FROM WRN TN EXTENDING SEWD ACROSS AL AND GA. AS SFC TEMPS WARM SATURDAY...CONVECTION SHOULD INITIATE ALONG THE BOUNDARY AND MOVE SWD ACROSS THE REGION. FORECAST SOUNDINGS SHOW MODERATE TO STRONG INSTABILITY WITH WEAK VERTICAL SHEAR PROFILES. THIS SUGGESTS STORM MODE WILL BE PULSE IN NATURE. ALTHOUGH A CLUSTER OF STORMS WITH HAIL AND/OR ISOLATED WIND DAMAGE MAY STILL OCCUR...IT IS TOO EARLY TO IDENTIFY AN AREA WITH ENHANCED SEVERE POTENTIAL. UPGRADE TO SLIGHT RISK MAY BE NECESSARY ACROSS PARTS OF THE REGION ONCE THE AMOUNT OF INSTABILITY AND LOCATION OF MCS DEVELOPMENT BECOMES MORE CERTAIN. ..BROYLES.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 13:05:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 09:05:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271303 SWODY1 SPC AC 271301 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0801 AM CDT SAT MAY 27 2006 VALID 271300Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN PLAINS INTO NWRN MN... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF IL... ...SYNOPSIS... AMPLIFIED FLOW PATTERN IS FORECAST TO PERSIST TODAY AS DEEPENING UPPER TROUGH OVER THE PACIFIC COAST STATES MOVES SLOWLY EWD TOWARD THE INTERMOUNTAIN REGION...AND UPPER RIDGE BUILDS INTO THE ERN STATES IN THE WAKE OF THE DEPARTING TROUGH ALONG THE ATLANTIC COAST. AT THE SURFACE...LOW PRESSURE IS EXPECTED TO REMAIN OVER THE NORTHERN HIGH PLAINS TODAY WITH A QUASISTATIONARY FRONT EXTENDING NEWD INTO SERN MANITOBA/NWRN ONTARIO...WHILE A COLD FRONT EXTENDING SWWD INTO WY AND UT MOVES SLOWLY SEWD. A NORTH/SOUTH DRY LINE WILL CONTINUE OVER THE CENTRAL/SRN HIGH PLAINS. IN THE EAST...A WEAK COLD FRONT WILL MOVE SWD ACROSS THE CAROLINAS...THEN RETURN NWWD AS A WARM FRONT THROUGH THE TN VALLEY TOWARD THE UPPER MS VALLEY. ...NRN PLAINS... STEEP MID LEVEL LAPSE RATES WILL REMAIN OVER THE REGION TODAY ABOVE INCREASINGLY MOIST BOUNDARY LAYER ALONG/SOUTH OF THE FRONT...RESULTING IN VERY UNSTABLE ENVIRONMENT WITH MLCAPE OF 2000-3500 J/KG THIS AFTERNOON AND EVENING. WARM LAYER ABOVE 850 MB IN WARM SECTOR SOUNDINGS IS EXPECTED TO INHIBIT CONVECTIVE DEVELOPMENT INTO THE AFTERNOON...WITH GREATER THREAT FOR CONVECTION DEVELOPING ALONG/NORTH OF THE FRONT LATER THIS AFTERNOON AND EVENING IN RESPONSE TO STRENGTHENING CONVERGENCE AND WARM ADVECTION ASSOCIATED WITH LOW LEVEL JET. ALTHOUGH STRONGEST SWLY FLOW ALOFT IS FORECAST TO LAG WELL TO THE WEST OF THE WARM SECTOR...VERTICAL SHEAR NEAR THE FRONT WILL BE SUFFICIENTLY STRONG TO ENHANCE CONVECTIVE ORGANIZATION AND PROMOTE DEVELOPMENT OF A FEW SUPERCELLS. PARTS OF CENTRAL AND ERN ND...ESPECIALLY ALONG/NORTH OF THE FRONT...APPEAR TO HAVE GREATEST SEVERE POTENTIAL WITH THE POSSIBILITY OF STORMS PRODUCING VERY LARGE HAIL AND A FEW TORNADOES...IN ADDITION TO DAMAGING WIND GUSTS. THIS ACTIVITY IS EXPECTED TO MOVE NEWD TONIGHT WITH ISOLATED SEVERE STORMS POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...ERN NEB/IA INTO IL AREA... RADAR IMAGERY INDICATES TWO MCV'S ASSOCIATED WITH MORNING CONVECTION...WITH BETTER-DEFINED MCV MOVING EWD INTO ERN IA AND TRAILING CIRCULATION MOVING FROM ERN NEB INTO EXTREME WRN IA. THUNDERSTORMS ALONG LEADING EDGE OF ERN IA MCV HAVE WEAKENED...BUT ADDITIONAL STORMS HAVE DEVELOPED WWD ACROSS NWRN MO INTO ERN NEB NORTH OF THE EARLIER OUTFLOW BOUNDARY. 12Z TOP SOUNDING EXHIBITS STEEP LAPSE RATE ABOVE 680 MB WITH MORE THAN 2000 J/KG OF ELEVATED CAPE FOR PARCELS ORIGINATING AROUND 750 MB....SUGGESTING A THREAT FOR HAIL WITH STRONGER CELLS. ACTIVITY IS LIKELY TO SPREAD EWD ACROSS EXTREME NRN MO/EXTREME SRN IA INTO MID MORNING BEFORE WEAKENING AFTER IT MOVES EAST OF THE LOW LEVEL JET. NEW THUNDERSTORMS ARE EXPECTED TO DEVELOP DOWNSTREAM FROM THE LEAD MCV THIS AFTERNOON AS IT MOVES SLOWLY EWD TODAY AND INTERACTS WITH INCREASINGLY MOIST/UNSTABLE ENVIRONMENT OVER PARTS OF NRN/CENTRAL IL. COMBINATION OF AMPLE LOW LEVEL MOISTURE /SURFACE DEW POINTS REACHING 65-70F/ AND STRONG INSOLATION WILL CONTRIBUTE TO DESTABILIZATION WITH MLCAPE 1500-2500 J/KG. THUNDERSTORMS ARE EXPECTED TO INCREASE IN INTENSITY THIS AFTERNOON/EVENING WITH THREAT FOR LARGE HAIL AND DAMAGING WIND GUSTS. ...TN VALLEY INTO SERN STATES... MOIST UNSTABLE AIR MASS IS EXPECTED TO CONTINUE ALONG/SOUTH OF THE FRONT THAT IS FORECAST TO MOVE SWD ACROSS THE CAROLINAS INTO GA. STRONG DIURNAL HEATING COUPLED WITH A WEAK CAP WILL RESULT IN SCATTERED AREAS OF THUNDERSTORMS DEVELOPING THIS AFTERNOON. WEAK VERTICAL SHEAR SUGGESTS PULSE STORMS WILL BE THE DOMINANT CONVECTIVE TYPE WITH POTENTIAL FOR ISOLATED BRIEF WET MICROBURSTS AND HAIL WITH STRONGER STORMS. ...CENTRAL/SRN HIGH PLAINS... UNSTABLE AIR MASS IS EXPECTED TO PERSIST ALONG/EAST OF THE DRY LINE THIS AFTERNOON. HOWEVER...WEAK LOW LEVEL CONVERGENCE WITHIN A CAPPED ENVIRONMENT AND MINIMAL FORCING FOR LARGE SCALE ASCENT WILL LIKELY TO INHIBIT CONVECTIVE DEVELOPMENT. ALTHOUGH MOST MODELS EXCEPT PARALLEL NAM GENERATE LITTLE IF ANY CONVECTION IN THE HIGH PLAINS...FORECAST SOUNDINGS INDICATE CIN WILL GRADUALLY DIMINISH DURING MAXIMUM HEATING PERIOD WILL WELL-MIXED BOUNDARY LAYER DEVELOPING. THIS SUGGESTS THAT A LOW PROBABILITY FOR THUNDERSTORMS SHOW BE MAINTAINED WITH COINCIDENT THREAT FOR ISOLATED SEVERE CELLS ALONG/EAST OF DRY LINE. ..WEISS/GUYER.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 16:31:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 12:31:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271626 SWODY1 SPC AC 271624 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT SAT MAY 27 2006 VALID 271630Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF WEST TX AND SOUTHWEST OK... ...DAKOTAS AND NWRN MN... UPPER TROUGH OVER THE WESTERN STATES CONTINUES TO AMPLIFY TODAY...WHILE UPPER RIDGE BUILDS OVER THE CENTRAL AND EASTERN U.S. MAIN SURFACE LOW WILL DEVELOP FROM NORTHEAST WY ACROSS SD INTO ND TONIGHT...ALONG SURFACE WARM FRONT. MODEL SOUNDINGS IN THIS AREA SHOW STEEP LOW AND MID LEVEL LAPSE RATES AND MLCAPE VALUES OVER 3500 J/KG. SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP AHEAD OF LOW FROM BLACK HILLS REGION INTO CENTRAL/WESTERN ND...MAINLY AFTER 00Z. SUPERCELLS CAPABLE OF LARGE HAIL/DAMAGING WINDS AND PERHAPS ISOLATED TORNADOES ARE EXPECTED. STORMS MAY SPREAD EASTWARD DURING THE LATE EVENING INTO NORTHWEST MN. DEVELOPMENT FARTHER SOUTH IS EXPECTED TO BE PRECLUDED BY CAPPING INVERSION AND WARM TEMPERATURES ALOFT. ...MN/WI/IA/IL... CLUSTER OF THUNDERSTORMS IS ONGOING THIS MORNING OVER SOUTHWEST IA. THIS ACTIVITY IS JUST NORTH OF REMNANT OUTFLOW BOUNDARY...AND ON NOSE OF STRONGER SOUTHERLY LOW LEVEL JET. WARMING TEMPERATURES ALOFT SHOULD TEND TO WEAKEN STORMS IN THIS REGION BY EARLY AFTERNOON. HOWEVER...NEW STORMS MAY DEVELOP FARTHER NORTHEASTWARD INTO PARTS OF MN/WI/IA AND NORTHERN IL AS MCV DRIFTS INTO AREA. MODELS AGREE ON DEVELOPING MODERATE-STRONG INSTABILITY IN THIS REGION...FAVORABLE FOR HAIL AND GUSTY WINDS. MODELS ALSO SUGGEST THAT ACTIVITY MAY PERSIST MUCH OF THE NIGHT DUE TO STRENGTHENING NOCTURNAL LOW LEVEL JET AND ENHANCED LOW LEVEL WARM ADVECTION. ...WEST TX INTO SOUTHWEST OK... DIFFUSE DRYLINE IS EXPECTED TO BECOME ESTABLISHED THIS AFTERNOON FROM SOUTHWEST OK INTO THE BIG BEND REGION OF TX. HOT SURFACE TEMPERATURES APPROACHING 100F...COUPLED WITH DEWPOINTS NEAR 60F EAST OF DRYLINE...WILL RESULT IN A ZONE OF HIGH INSTABILITY /MLCAPE VALUES OF 2000-3000 J/KG/. FORECAST SOUNDINGS SHOW A DEEP MIXED BOUNDARY LAYER AND NO CAP...LIKELY RESULTING IN SCATTERED THUNDERSTORM DEVELOPMENT NEAR/JUST AFTER PEAK HEATING. WATER VAPOR IMAGERY HINTS AT A WEAK UPPER FEATURE MOVING INTO WEST TX. THIS MAY HELP TO ORGANIZE CONVECTION AND ENHANCE THREAT OF LOCALLY DAMAGING WINDS AND HAIL IN STRONGER CELLS. THUS...HAVE INTRODUCED A SLIGHT RISK FOR THIS AREA. ...TN VALLEY INTO THE SOUTHEAST... WEAK SURFACE BOUNDARY CURRENTLY EXTENDS FROM SC/GA INTO IL. AIR MASS ALONG AND SOUTH OF BOUNDARY REMAINS VERY MOIST/UNSTABLE WITH AFTERNOON MUCAPE VALUES EXPECTED TO RANGE FROM 3000-4000 J/KG. VERTICAL SHEAR PROFILES ARE WEAK IN THIS AREA. HOWEVER...ISOLATED PULSE OR MULTICELL SEVERE STORMS ARE POSSIBLE ALONG THIS AXIS. THREAT SHOULD SUBSIDE BY EARLY EVENING. ...SOUTH FL... SUBTROPICAL JET REMAINS ACROSS SOUTH FL TODAY...WITH WATER VAPOR IMAGERY SHOWING WELL-DEFINED SHORTWAVE TROUGH OVER THE CENTRAL GULF OF MEXICO. AMPLE MOISTURE/INSTABILITY ARE PRESENT OVER THIS REGION...LIKELY LEADING TO SCATTERED AFTERNOON THUNDERSTORMS. SUFFICIENT UPPER LEVEL WIND FIELDS AND FAVORABLE THERMODYNAMIC PARAMETERS SUGGEST A THREAT OF GUSTY WINDS AND HAIL IN STRONGER CELLS. ..HART/TAYLOR.. 05/27/2006  From swody1 at goshenarc.org Sat May 27 20:00:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 16:00:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271959 SWODY1 SPC AC 271957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT SAT MAY 27 2006 VALID 272000Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN PLAINS TO THE UPPER MS VLY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN GA AND SRN SC... ...NRN PLAINS... 19Z SFC ANALYSIS PLACES A SFC LOW SW OF KBIS WITH A FRONT SITUATED FROM CYWG-KDIK-KGCC. 18Z BIS RAOB SHOWED SUBSTANTIAL CINH IN THE WARM SECTOR WITH H7 TEMPERATURES AOA 12 DEGREES C AND CONVECTIVE TEMPERATURES IN THE MID 90S. PROFILERS/VWPS SEEM TO SUGGEST THAT A SPEED MAX IS DEVELOPING NEWD THROUGH THE CNTRL ROCKIES AND MAY BE AIDING HIGH BASED CONVECTION ACROSS THE SANDHILLS OF NEB AND ECNTRL WY. AS THIS FEATURE MOVES INTO THE DAKS LATER THIS EVENING...TSTMS ARE APT TO DEVELOP. QUESTION REMAINS IF STORMS WILL DEVELOP IN THE WARM SECTOR OR ON THE COLD SIDE OF THE FRONT. MOST LIKELY SCENARIO WOULD BE FOR NOCTURNAL STORMS TO FORM ATOP THE COLDER AIR ACROSS THE HIGHER PLAINS WITH THREATS FOR LARGE HAIL. BUT...THERE WILL BE A CONDITIONAL THREAT FOR MORE SFC-BASED STORMS TO DEVELOP ALONG THE EDGE OF THE STRONGER CAP IN EXTREME NRN SD AND CNTRL/ERN ND THIS EVE. 0-6KM SHEAR IN THE WARM SECTOR WAS WEAK...BUT MAGNITUDE OF LAPSE RATES SUGGEST ANY STORM COULD EVOLVE INTO SUPERCELLS WITH LARGE HAIL...HIGH WINDS AND A TORNADO OR TWO. EVOLUTION INTO A NOCTURNAL MCS SEEMS REASONABLE AS THE LLJ ACCELERATES...CROSSING THE RED RVR VLY BY EARLY SUNDAY MORNING. ...UPPER MS VLY... DIFFERENTIAL HEATING ON THE PERIPHERY OF A MORNING CORN BELT MCS HAS DESTABILIZED THE BOUNDARY LAYER ACROSS THE UPPER MS VLY. THIS HAS CONTRIBUTED TO INCREASING DEEP MOIST CONVECTION DOWNSTREAM... ARCING FROM ECNTRL MN THROUGH CNTRL WI...THEN SWWD INTO NRN IL. ACTIVITY SHOULD CONTINUE TO SPREAD RADIALLY OUTWARD...REACHING UPPER MI AND SRN WI...NRN IL THROUGH THE NIGHT. AT LEAST THROUGH MID-EVENING...STORMS MAY CONTAIN LARGE HAIL AND DAMAGING WIND GUSTS. ...SRN HIGH PLAINS... MODEST BOUNDARY LAYER MSTR HAS BEEN MAINTAINED ALONG/E OF THE CAPROCK SWD INTO THE LWR TRANSPECOS VLY AND THE BIG BEND REGION. TSTMS HAVE INITIATED...PRIMARILY OVER THE DAVIS...DEL NORTE MOUNTAINS OF SW TX. FARTHER N...A PERSISTENT CU FIELD WAS EVIDENT OVER THE LOW ROLLING PLAINS AND BENEATH A MID-LEVEL CLOUD PATCH OVER THE SRN HIGH PLAINS OF W TX. AS THE BOUNDARY LAYER CONTINUES TO HEAT...TSTMS WILL THRIVE NEAR THE SW TX MOUNTAINS AND PROBABLY INITIATE FARTHER N INVOF CAPROCK FROM JUST E OF KLBB SWD AFTER 22Z...AIDED BY A WEAK DISTURBANCE ALOFT. EFFECTIVE VERTICAL SHEAR IS EXPECTED TO REMAIN WEAK...BUT MAGNITUDE OF LAPSE RATES WILL FAVOR SLOW MOVING SUPERCELLS...SHOULD A STORM BECOME ESTABLISHED. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE THREATS. ACTIVITY SHOULD DIMINISH AFTER DARK. ...MID-SOUTH TO THE SERN STATES... NW-SE ORIENTED FRONT LIES FROM WRN TN ACROSS NRN AL TO THE SAV RVR VLY. SCT TSTMS HAVE BEEN FAVORING THIS ZONE OF CONVERGENCE AND WILL LIKELY CONCENTRATE ACROSS THE SAV RVR VLY VCNTY COLDER TEMPERATURES ALOFT AND ACROSS THE TN VLY TIED TO A WEAK MCV. VERTICAL SHEAR WAS VERY WEAK ACROSS THE REGION...BUT THE AIR MASS WAS QUITE UNSTABLE. THUS...ISOLD MULTICELL PULSE SEVERE STORMS CAN BE EXPECTED GIVING LOCAL DAMAGING WIND GUSTS OR HAIL. ACTIVITY SHOULD DIMINISH THIS EVENING. ...CNTRL/SRN FL... SLIGHTLY STRONGER AMBIENT BOUNDARY LAYER FLOW TODAY DELAYED THE SEA-BREEZE...BUT 19Z VSBL SATL SHOWS TSTMS BEGINNING TO INCREASE ACROSS CNTRL/SRN FL. GIVEN PRESENCE OF A WEAK VORT MAX MOVING ACROSS THE CNTRL/SRN PORTIONS OF THE STATE...RELATIVELY STEEP MID-LEVEL LAPSE RATES AND MOIST BOUNDARY LAYER...ISOLD STRONG-SEVERE STORMS CAN BE EXPECTED. STORMS SHOULD MOVE EWD TOWARD THE ECOAST DURING THE EVENING WITH ISOLD DAMAGING WINDS AND HAIL. ..RACY.. 05/27/2006  From swody1 at goshenarc.org Sun May 28 01:14:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 27 May 2006 21:14:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280113 SWODY1 SPC AC 280111 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0811 PM CDT SAT MAY 27 2006 VALID 280100Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS SRN HIGH PLAINS... ...NRN HIGH PLAINS... POTENT LEE-SIDE CYCLONE IS FORECAST TO TRACK NEWD ALONG INTENSE BAROCLINIC ZONE SITUATED FROM WRN SD THROUGH CNTRL ND THROUGH EARLY SUNDAY. VERY HOT AND UNSTABLE AIR MASS WAS PRESENT ACROSS CNTRL DAKOTAS AND WILL FUEL NUMEROUS SEVERE STORMS...PRIMARILY ACROSS ND WHERE FORCING CAN OVERCOME STRONG CAP/INHIBITION SITUATED ACROSS THE BULK OF THE GREAT PLAINS. GIVEN STRENGTH OF LOW LEVEL JET/SHEAR AND MASS INFLOW INTO THE DEVELOPING STORMS...SUPERCELLS WITH LARGE HAIL AND HIGH WINDS APPEAR LIKELY. TORNADO POTENTIAL WILL ALSO EXIST FOR DISCRETE CELLS TRACKING NEAR THE FRONTAL BOUNDARY OVER THE NEXT FEW HOURS. ...NERN IA/MN/WI... STRONG STORMS HAVE BEEN REDEVELOPING ACROSS WI...IN THE WAKE OF EARLIER MCS NOW DECAYING ACROSS LAKE MI/UPPER MI. BROADLY DIFFLUENT FLOW ALOFT AND INCREASING LIFT/WAA ACROSS THE REGION SHOULD SUPPORT ADDITIONAL DEVELOPMENT...OR SUSTAIN ONGOING CONVECTION OVER THE NEXT SEVERAL HOURS. NEAR SURFACE-BASED DEVELOPMENT HAS RECENTLY FORMED ON THE NRN EDGE OF INTENSE INSTABILITY ACROSS NERN IA WHERE DIAGNOSTIC DATA INDICATES SUFFICIENT EFFECTIVE SHEAR EXISTS FOR SUPERCELLS. DESPITE SOME INHIBITION INDICATED ON EVENING SOUNDINGS FROM IA/MN...CONTINUED STRONG WAA OVER THIS AREA...COUPLED WITH PRESENCE OF VERY STEEP LAPSE RATES...SHOULD RESULT IN AN INCREASING CHANCE OF SCATTERED SEVERE HAIL OVERNIGHT...AND PERHAPS A BRIEF TORNADO WHERE LOW LEVEL FLOW IS BACKED IN THE WAKE OF EARLIER MCS. ...SRN HIGH PLAINS... WEAK HEIGHT FALLS/BACKGROUND ASCENT ROTATING OUT AHEAD OF THE LARGE SCALE WRN TROUGH...AND STRONG DEEP-LAYER HEATING/MIXING HAVE PROMOTED A NUMBER OF SEVERE HIGH-BASED TSTMS FROM THE RIO GRANDE NWD TO THE TX/OK PNHDLS. BAND OF 30KT WLY MID LEVEL FLOW ATOP WEAK SLY/VARIABLE FLOW WITHIN DEEP BOUNDARY LAYER WAS RESULTING IN ADEQUATE SHEAR FOR A FEW SUSTAINED ROTATING UPDRAFTS. HAIL AND HIGH WINDS SHOULD ACCOMPANY THIS ACTIVITY FOR AT LEAST A FEW MORE HOURS. IT IS POSSIBLE A SMALL MCS OR TWO COULD EVOLVE AS ACTIVITY DRIFTS GRADUALLY EAST INTO STRONGER INSTABILITY THROUGH THE EVENING. HOWEVER...STRONG INHIBITION...AND MASS INFLOW DIRECTED AWAY FROM THE REGION AND INTO THE STRONGER SYSTEM ACROSS THE NRN PLAINS...SHOULD LIMIT OVERALL SEVERE STORM COVERAGE LATER TONIGHT. ..CARBIN.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 05:58:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 01:58:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280557 SWODY1 SPC AC 280555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT SUN MAY 28 2006 VALID 281200Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM WRN/NRN NEB ACROSS THE ERN DAKOTAS AND WRN MN... ...SYNOPSIS... STRONGLY AMPLIFIED MID/UPPER LEVEL FLOW PATTERN WILL FEATURE A LARGE SUMMER-LIKE RIDGE ACROSS MUCH OF THE EAST...AND A RELATIVELY DEEP TROUGH ACROSS THE WEST AND ROCKIES. SHORT WAVE IMPULSES EMANATING FROM THE WRN TROUGH AND ENCOUNTERING STRONG DOWNSTREAM RIDGING HAVE BEEN LIFTING NNEWD/NEWD ACROSS THE HIGH PLAINS AND UPPER MS VALLEY OVER THE WEEKEND AND DRIVING MCS DEVELOPMENT ACROSS THESE AREAS...AS WELL AS ACROSS SCNTRL CANADA. EXTENSIVE PLUME OF WARM AIR ALOFT COVERING MUCH OF THE GREAT PLAINS AND PARTS OF THE MIDWEST HAS LIMITED MORE WIDESPREAD TSTM DEVELOPMENT OVER THESE REGIONS DESPITE PRONOUNCED DIURNAL DESTABILIZATION. SIMILAR CONDITIONS WILL PERSIST TODAY. A STRONG IMPULSE/SPEED MAX CURRENTLY CROSSING THE SRN GREAT BASIN IS FORECAST TO PIVOT NEWD AROUND THE ERN FLANK OF THE LARGE SCALE WRN TROUGH AND PRODUCE MODEST HEIGHT FALLS FROM CO TO THE WRN DAKOTAS THROUGH SUNDAY NIGHT. SHARP BAROCLINIC ZONE...ALIGNED WITH DEEP-LAYER MERIDIONAL FLOW FROM CO TO ND...WILL PROVIDE FOCUS FOR TRIPLE POINT LOW FORMATION ON COLD FRONT/DRYLINE/STATIONARY FRONT INTERSECTION NERN CO TO WRN/CNTRL NEB PNHDL DURING LATE AFTERNOON AS WRN IMPULSE APPROACHES. ANOTHER SURFACE LOW WILL BE SITUATED ON THE BOUNDARY OVER ERN ND...ASSOCIATED WITH A LEADING IMPULSE LIFTING INTO SRN CANADA. THE ND LOW IS FORECAST TO TRACK INTO SRN MANITOBA THROUGH THE EVENING WHILE CO/NEB SURFACE LOW MOVES NEWD ACROSS TO NRN NEB...AND THEN TO ERN SD/WRN MN THROUGH MONDAY MORNING. COLD FRONT ASSOCIATED WITH THE NEB LOW WILL SURGE SWD ACROSS THE CNTRL HIGH PLAINS TO SWRN KS BY THE END OF THE FORECAST PERIOD. ...NEB/DAKOTAS... VERY STRONG TO EXTREME WARM SECTOR INSTABILITY WILL AGAIN DEVELOP FROM CNTRL/ERN NEB NWD ACROSS ND/MN THIS AFTERNOON WITH MLCAPE VALUES IN THIS CORRIDOR AOA 2500 J/KG. DESPITE TEMPERATURES CLIMBING INTO THE 90S ACROSS THE WARM SECTOR...CONVECTIVE INHIBITION WILL AGAIN LIMIT SURFACE-BASED STORM DEVELOPMENT TO THOSE AREAS WHERE EITHER EXCESSIVE HEATING/MIXING...AND/OR PERSISTENT STRONG FORCING CAN OVERCOME THE CAP. MOST LIKELY AREAS TO EXPERIENCE THESE CONDITIONS...LEADING TO SURFACE-BASED TSTM INITIATION...APPEAR TO BE NEAR THE LEADING SURFACE LOW OVER NERN ND...AND NEAR TRIPLE POINT LOW MOVING TOWARD NCNTRL NEB DURING THE EVENING. STORMS DEVELOPING NEAR THESE FEATURES WILL ENCOUNTER SUFFICIENT SHEAR AND INSTABILITY FOR ORGANIZATION/PERSISTENCE WITH VERY LARGE HAIL/HIGH WINDS...AND PERHAPS AN ISOLATED TORNADO OR TWO. LATEST DETERMINISTIC AND ENSEMBLE GUIDANCE SUGGESTS THAT GREATER STORM COVERAGE IS MORE LIKELY TO OCCUR ON THE COOLER/DRIER SIDE OF THE FRONTAL ZONE...FROM NERN CO/WRN NEB ACROSS CNTRL SD THROUGH THE LATE NIGHT. THIS SCENARIO APPEARS REALISTIC GIVEN STRONGER HEIGHT FALLS TO THE WEST OF THE DEEP LAYER BAROCLINIC ZONE... MERIDIONAL CONFIGURATION OF THE LARGER SCALE SYSTEM...AND STRENGTH OF THE CAP. EVEN THOUGH THIS POST-FRONTAL ACTIVITY MAY BE ROOTED ABOVE A MORE STABLE BOUNDARY LAYER...EXTREME SHEAR...STRONG FORCING...AND STEEP LAPSE RATES SHOULD RESULT IN NUMEROUS INTENSE STORMS/SUPERCELLS WITH LARGE HAIL POTENTIAL. AS THIS CONVECTION EVOLVES INTO AN MCS AND SPREADS NEWD ACROSS NEB/SD THROUGH LATE TONIGHT...OUTFLOW REINFORCED FRONTAL SURGE MAY PROVE SUFFICIENT TO PROMOTE ADDITIONAL HIGH-BASED TSTMS...WITH SOME WIND AND HAIL THREAT SPREADING EAST TO ERN NEB AND WRN MN THROUGH EARLY MONDAY. ...DRYLINE FROM SRN NEB TO WEST TX... STRONG HEATING/MIXING WILL AGAIN PRODUCE POCKETS OF MESOSCALE FORCING SUFFICIENT FOR ISOLATED HIGH-BASED TSTM DEVELOPMENT BY LATE AFTERNOON THESE AREAS. UNLIKE SATURDAY AFTERNOON...GRADUAL HEIGHT RISES AND GENERALLY WEAKER MID LEVEL FLOW/SHEAR MAY TEND TO LIMIT OVERALL STORM COVERAGE/INTENSITY AND ONLY A LOW PROBABILITY WIND/HAIL THREAT APPEARS WARRANTED FOR THE DRYLINE TODAY. ...TX/LA GULF COAST TO LOWER MS VALLEY... WEAK IMPULSE/MCV CURRENTLY TRACKING EWD ACROSS SOUTH TX COULD ENHANCE TSTM POTENTIAL IN VERY MOIST UNSTABLE GULF COAST AIR MASS. STRONG INFLUX OF GULF MOISTURE AROUND SWRN FLANK OF EAST COAST ANTICYCLONE WILL FUEL A FEW INTENSE STORM CLUSTERS SPREADING INLAND SIMILAR TO SATURDAY ACROSS LA. A COUPLE OF HAIL EVENTS AND A FEW WET MICRO BURSTS APPEAR POSSIBLE. ....FL/AL/GA... RESIDUAL FRONT SITUATED ACROSS AL/GA BORDER MAY AGAIN PROVIDE A FOCUS FOR AFTERNOON STORMS IN VERY UNSTABLE AND WEAKLY CAPPED ENVIRONMENT. ADDITIONALLY...STRONG INSTABILITY AND SEA/GULF BREEZE COLLISION ACROSS FL WILL RESULT IN NUMEROUS STRONG STORMS OVER THE PENINSULA. DESPITE LIMITED SHEAR...STORM MERGERS AND BOUNDARY INTERACTIONS IN VERY MOIST AND UNSTABLE REGIME SHOULD RESULT IN A FEW SEVERE WIND/HAIL EVENTS. ..CARBIN/GUYER.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 13:05:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 09:05:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281304 SWODY1 SPC AC 281302 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0802 AM CDT SUN MAY 28 2006 VALID 281300Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN HIGH PLAINS... ...SYNOPSIS... WATER VAPOR IMAGERY SUGGESTS JET STREAK IS MOVING INTO BASE OF THE DEEP UPPER TROUGH OVER THE WRN STATES...SUGGESTING SYSTEM HAS REACHED MAXIMUM AMPLITUDE. AS JET STREAK BEGINS TO MOVE NEWD ON EAST SIDE OF TROUGH...TROUGH WILL ALSO LIFT NEWD ACROSS NRN ROCKIES TODAY AND INTO CANADA TONIGHT AS DOWNSTREAM RIDGE BUILDS OVER ERN STATES. AT THE SURFACE...NORTHEAST/SOUTHWEST QUASI-STATIONARY FRONT FROM SERN MANITOBA INTO LOW OVER EXTREME NRN SD...THEN CONTINUES SWWD INTO SECOND LOW OVER NERN CO. A COLD FRONT TRAILS SWWD FROM THE CO LOW INTO FOUR-CORNERS REGION AND NWRN AZ. THE SD LOW IS EXPECTED TO LIFT NEWD ALONG THE FRONT TOWARD NERN ND THIS AFTERNOON AND INTO SERN MANITOBA TONIGHT. THE CO LOW IS FORECAST TO MOVE LITTLE TODAY BEFORE LIFTING NEWD AND WEAKENING TONIGHT AS COLD FRONT BEGINS TO MOVE EWD ACROSS THE NRN AND CENTRAL PLAINS...REACHING A NRN MN/ERN NEB/SERN CO LINE BY 29/12Z. A NORTH/SOUTH DRY LINE EXTENDING FROM WRN NEB AND KS INTO SERN NM AND THE TRANSPECOS REGION OF TX IS EXPECTED TO MIX EWD THIS AFTERNOON. IN THE EAST...WEAK COLD FRONT EXTENDS FROM THE GA COAST NWWD INTO NRN AL...CONTINUING NWWD AS A QUASI-STATIONARY FRONT ACROSS IND...THEN AS A WARM FRONT INTO NRN MN. SERN PART OF THE FRONT WILL MOVE SWD INTO THE FL PENINSULA TODAY. ...NRN PLAINS/NRN MN... ELEVATED THUNDERSTORMS HAVE DEVELOPED OVER EXTREME NRN MN NORTH OF THE SURFACE WARM FRONT WITHIN THAT LAST HOUR. 12Z INL SOUNDING EXHIBITS STRONG INSTABILITY ABOVE COOL SURFACE-BASED LAYER...WITH MODEST EFFECTIVE SHEAR. PRIMARY THREAT WILL BE LARGE HAIL OVER PARTS OF KOOCHICHING...NRN ST LOUIS...AND POSSIBLY LAKE AND COOK COUNTIES DURING THE NEXT 2 HOURS...AFTER WHICH ACTIVITY SHOULD MOVE INTO ONTARIO. AMPLE LOW LEVEL MOISTURE /SURFACE DEW POINTS IN THE MID/UPPER 60S/IN THE WARM SECTOR COUPLED WITH STEEP MID LEVEL LAPSE RATES ASSOCIATED WITH ELEVATED MIXED LAYER WILL CONTRIBUTE TO STRONG INSTABILITY THIS AFTERNOON WITH MLCAPE REACHING 2500-3500 J/KG. 12Z SOUNDINGS SHOW A STRONG CAP JUST ABOVE 850 MB...AND THIS IS LIKELY TO REMAIN IN PLACE INTO THE AFTERNOON INHIBITING DEVELOPMENT OF SURFACE-BASED CONVECTION EAST OF THE FRONT. MODEL GUIDANCE INDICATES INITIAL STORMS THIS AFTERNOON WILL BE ELEVATED WEST OF SURFACE FRONT OVER NORTH CENTRAL CO/ERN WY/NEB PANHANDLE AND WRN SD...FORMING IN RESPONSE TO DYNAMIC FORCING ASSOCIATED WITH MID/UPPER LEVEL JET STREAK LIFTING NNEWD FROM THE CENTRAL TOWARD THE NRN HIGH PLAINS. THIS CONVECTION IS LIKELY TO SPREAD NEWD WEST OF THE FRONT INTO PARTS OF THE DAKOTAS DURING THE EVENING...WHILE POTENTIAL EXISTS FOR ADDITIONAL STORMS TO DEVELOP ALONG THE FRONT FROM ERN SD INTO EXTREME ERN ND/NWRN MN. STRONGEST DEEP LAYER SHEAR WILL BE LOCATED WEST OF THE FRONT AND WILL SUPPORT ELEVATED SUPERCELLS IN THAT REGION. ALTHOUGH SHEAR DIMINISHES WITH EWD EXTENT INTO THE WARM SECTOR IT SHOULD BE SUFFICIENT TO ENHANCE ORGANIZED SEVERE STORM THREAT WITH ANY SURFACE-BASED STORMS ALONG THE FRONT. LARGE HAIL IS EXPECTED TO BE THE PRIMARY THREAT ALONG WITH DAMAGING WIND GUSTS. ACTIVITY IS EXPECTED TO CONTINUE NEWD INTO THE OVERNIGHT HOURS. ...CENTRAL/SRN HIGH PLAINS... UNSTABLE AIR MASS WILL EXTEND ALG/EAST OF THE DRY LINE AS MOISTURE RETURNS WWD IN THE WAKE OF MORNING CONVECTION OVER PARTS OF SRN OK AND CENTRAL TX. ALTHOUGH LARGE SCALE ASCENT WILL BE MINIMAL AS UPPER TROUGH LIFTS NEWD AWAY FROM THE REGION...COMBINATION OF STRONG HEATING AND WEAK CONVERGENCE ALONG THE DRYLINE MAY BE SUFFICIENT TO WEAKEN CAP AND PERMIT DEVELOPMENT OF A FEW THUNDERSTORMS DURING THE LATE AFTERNOON AND EVENING. VERY STEEP LAPSE RATES WILL ENHANCE UPWARD ACCELERATION FOR ANY PARCELS THAT REACH THE LFC...AND DEEP WELL-MIXED BOUNDARY LAYER WILL SUPPORT STRONG DOWNDRAFTS SUGGESTING THREAT FOR LARGE HAIL AND STRONG WIND GUSTS. SREF ETA-KF MEMBERS AND 06Z ETA SUGGEST MOST LIKELY REGION FOR CONVECTIVE DEVELOPMENT WILL BE ALONG GAG-SJT AXIS...AND SLIGHT RISK HAS BEEN ADDED TO THAT REGION. ...CENTRAL/ERN TX AND SERN OK INTO SWRN AR AND LA... ANIMATED RADAR IMAGERY OF CONVECTIVE SYSTEMS DURING THE PRE-DAWN HOURS INDICATED THE PRESENCE OF MCV/S OVER CENTRAL TX AND EXTREME NRN TX NEAR THE RED RIVER EAST OF SPS. IF THESE SYSTEMS MAINTAIN ORGANIZATION AND CONTINUE EWD TODAY...THEY MAY INCREASE THUNDERSTORM DEVELOPMENT FROM CENTRAL/ERN TX AND SERN OK EWD INTO SWRN AR AND LA. PRESENCE OF MODERATELY UNSTABLE PRE-CONVECTIVE ENVIRONMENT WITH MLCAPE OF 2000-3000 J/KG AND DYNAMICALLY ENHANCED MID LEVEL WINDS/ASSOCIATED VERTICAL SHEAR SUGGESTS POTENTIAL FOR ISOLATED SEVERE STORMS THIS AFTERNOON AND EVENING. ...PARTS OF AL/GA/FL... COLD FRONT SAGGING SWD/SWWD ACROSS PARTS OF GA INTO AL AND FL IS EXPECTED TO PROVIDE FOCUS FOR THUNDERSTORM DEVELOPMENT TODAY. 12Z REGIONAL SOUNDINGS SUGGEST MLCAPE WILL INCREASE TO 2000-2500 J/KG AS STRONG INSOLATION OCCURS. WEAK VERTICAL SHEAR COUPLED WITH DRY AIR AVAILABILITY AND STEEP LOW LEVEL LAPSE RATES SUGGEST POTENTIAL FOR PULSE STORMS WITH MARGINAL HAIL AND ISOLATED WET MICROBURSTS. ..WEISS/GUYER.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 16:35:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 12:35:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281629 SWODY1 SPC AC 281628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT SUN MAY 28 2006 VALID 281630Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NORTHERN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF WESTERN OK AND TX... WATER VAPOR LOOPS SHOW STRONG UPPER TROUGH ROTATING EASTWARD ACROSS UT. THIS FEATURE WILL SURGE INTO CO/WY THIS EVENING...AND INTO THE NORTHERN HIGH PLAINS BY MONDAY MORNING. STRONG SOUTHERLY LOW LEVEL WINDS AHEAD OF SYSTEM WILL MAINTAIN AMPLE MOISTURE IN WARM SECTOR OF SURFACE LOW MOVING FROM CO INTO WESTERN MN DURING THE PERIOD. HOWEVER...VERY WARM 700MB TEMPERATURES SHOULD EFFECTIVELY CAP THE WARM SECTOR. THIS WILL FOCUS GREATEST THREAT OF DEEP CONVECTION TO THE NORTH/WEST OF SURFACE LOW AND WARM FRONT...AND IN THE HIGH PLAINS WHERE STRONG HEATING AND DEEP MIXING WILL AID CONVECTIVE INITIATION. ...NORTHERN ND/MN... SCATTERED THUNDERSTORMS CONTINUE TO FORM THIS MORNING IN LOW/MID LEVEL WARM ADVECTION ZONE ACROSS NORTHERN ND AND NORTHERN MN...INTO SOUTHERN MANITOBA/NORTHWEST ONTARIO. RICH LOW LEVEL MOISTURE HAS BECOME ESTABLISHED FROM CENTRAL ND INTO MN WITH DEWPOINTS NEAR 70F. INCREASING CAPPING INVERSION OVER THIS REGION WILL LIMIT AREAL COVERAGE OF STORMS. HOWEVER...STRONG HEATING WITH AFTERNOON TEMPS NEAR 90F WILL RESULT IN MLCAPE VALUES OVER 4000 J/KG. LOW AND MID LEVEL WIND FIELDS WILL NOT BE VERY STRONG...BUT SOME VEERING WITH HEIGHT AND REMNANT BOUNDARIES MAY PROMOTE SUPERCELL DEVELOPMENT AND THREAT OF LARGE HAIL AND DAMAGING WINDS. ISOLATED TORNADOES CANNOT BE RULED OUT THIS AFTERNOON AND EVENING. ...WY/NEB/SD/ND/MN... STRONG DAYTIME HEATING WILL OCCUR THIS AFTERNOON ACROSS EASTERN WY AND WESTERN SD/NEB...RESULTING IN NEAR DRY-ADIABATIC LOW/MID LEVEL LAPSE RATES AND DEEP MIXING. THIS SHOULD AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER THIS REGION...WEST OF PRIMARY MOISTURE GRADIENT. THESE HIGH-BASED STORMS MAY PRODUCE LOCALLY GUSTY WINDS AND HAIL. ACTIVITY IS EXPECTED TO INTERACT WITH RICHER MOISTURE PLUME BY EARLY EVENING ACROSS WESTERN SD/NEB...WHERE FURTHER INTENSIFICATION IS EXPECTED. THESE STORMS ARE LIKELY TO SPREAD NORTHEASTWARD TOWARD SOUTHEAST ND AND WESTERN MN OVERNIGHT. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE IN STRONGER CELLS. ...WEST TX/OK... ANOTHER DAY OF FULL SUNSHINE AND DEEP MIXING WILL OCCUR TODAY ALONG THE DIFFUSE DRYLINE OVER WEST TX AND WESTERN OK. ISOLATED THUNDERSTORM DEVELOPMENT APPEARS POSSIBLE ALONG THIS AXIS...ALTHOUGH DRIER AIR ON WATER VAPOR IMAGERY AND SLIGHTLY WEAKER FORECAST SHEAR PROFILES SUGGEST LESS COVERAGE AND INTENSITY THAN YESTERDAY. HIGH-BASED STORMS CAPABLE OF GUSTY WINDS AND HAIL ARE THE MAIN THREAT. ...SOUTHEAST TX/SOUTHWEST LA... LARGE CLUSTER OF THUNDERSTORMS IS ONGOING THIS MORNING OVER THE MIDDLE TX GULF COAST. THESE STORMS MAY PERSIST FOR SEVERAL MORE HOURS...ALONG WITH THE THREAT OF EASTWARD DEVELOPMENT ALONG COAST. HIGH CAPE VALUES AND WEAK VERTICAL SHEAR SUGGEST THAT PULSE-TYPE SEVERE STORMS ARE MOST LIKELY...WITH LOCALLY GUSTY WINDS. ...GA/FL... UPPER RIDGE AXIS EXTENDS FROM EASTERN AL ALONG THE FL PENINSULA TODAY. AIR MASS UNDER RIDGE IS VERY MOIST/UNSTABLE WITH DEWPOINTS NEAR 70F AND AFTERNOON MLCAPE VALUES AROUND 2000 J/KG. WEAK WINDS ALOFT WILL LIMIT CONVECTIVE ORGANIZATION WITH PULSE-TYPE STORMS MOST LIKELY. HOWEVER...SEA-BREEZE INTERACTIONS AND REMNANT WEAK COLD FRONT MAY HELP FOCUS ACTIVITY WITH THE POTENTIAL FOR WET-MICROBURSTS AND HAIL IN STRONGEST CELLS. ..HART/LEVIT.. 05/28/2006  From swody1 at goshenarc.org Sun May 28 20:01:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 16:01:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281958 SWODY1 SPC AC 281957 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0257 PM CDT SUN MAY 28 2006 VALID 282000Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE SRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER SRN GA AND PARTS OF NRN/CNTRL FL... ...NRN PLAINS... 19Z SFC ANALYSIS PLACES A 995 LOW NCNTRL ND WITH A COLD FRONT EXTENDING S THROUGH CNTRL SD...THEN WWD ACROSS NCNTRL NEB INTO NERN CO. OUTFLOW FROM MANT/NWRN ONT MCS HAS STALLED FROM NEAR KINL WWD TO JUST N OF KRDR THEN TO THE LOW. THOUGH THE AIR MASS WAS BEGINNING TO RECOVER ALONG THE INTERNATIONAL BORDER...VERY WARM H8-H7 TEMPERATURES CONTINUES TO CAP A HOT AND MOIST BOUNDARY LAYER ACROSS THE PLAINS. LATEST RUC/ACARS SHOWS +14 DEGREE C H7 TEMPERATURES SURGING INTO SRN MANT/NWRN ONT THROUGH LATE AFTN. THUS...PROSPECTS FOR SFC-BASED STORM INITIATION ARE NOT HIGH...BUT NOT ENTIRELY OUT OF THE QUESTION...ALONG THE OUTFLOW BOUNDARY OR COLD FRONT THROUGH THE AFTN IN THE U.S. THUS...HAVE MAINTAINED CONDITIONAL LOW PROBABILITIES FOR TORNADOES AND/OR LARGE HAIL-DAMAGING WINDS OVER FAR NERN ND AND NWRN MN. UPSTREAM...BOUNDARY LAYER FLOW WAS BEGINNING TO TURN UPSLOPE ACROSS SWRN SD...NEB AND WY...OWING TO WY CYCLOGENESIS AND DIURNAL AFFECTS. WATER VAPOR SHOWS EVIDENCE OF A WEAK SPEED MAX MOVING NWD THROUGH THE CNTRL ROCKIES. AS WEAK HEIGHT FALLS/WEAK COOLING ALOFT SPREAD NEWD ACROSS THE HIGH PLAINS...TSTMS ARE EXPECTED TO INCREASE OVER THE HIGHER TERRAIN OF SD AND WY LATER THIS AFTN. THESE STORMS WILL PROBABLY DEVELOP ENEWD ALONG/N OF THE COLD FRONT INTO NWRN NEB AND SD OVERNIGHT. EFFECTIVE SHEAR IMPROVES WEST OF THE FRONT AND SUPERCELLS WILL BE POSSIBLE WITH LARGE HAIL ALONG THE HIGHER PLAINS. IT IS NOT CLEAR HOW OVERNIGHT ACTIVITY WILL EVOLVE...BUT IT IS REASONABLE TO EXPECT A LOOSELY ORGANIZED MCS TO LIFT ENEWD ACROSS PARTS OF THE DAKS WITH RISKS OF DAMAGING WINDS...HAIL AND PERHAPS AN ISOLD TORNADO. ..SRN HIGH PLAINS... SATL SHOWS SMALL CU DEVELOPING VCNTY THE CAPROCK WHERE BOUNDARY LAYER HAS BECOME HOT AND SFC DEW POINTS HAVE REMAINED 52-61 DEGREE F. PRIND HIGH-BASED TSTMS WILL DEVELOP ALONG THE CAPROCK AFT 22Z AND COULD BRIEFLY BECOME SUPERCELLULAR. COVERAGE WILL BE LESS THAN YESTERDAY...BUT GIVEN MAGNITUDE OF LAPSE RATES...LARGE HAIL AND DAMAGING WINDS WILL BE LIKELY. ACTIVITY SHOULD DIMINISH DURING THE EVENING. ...DEEP S TX... COLD POOL FROM NIGHTTIME SCNTRL TX MCS HAS GONE STATIONARY NW-SE ACROSS DEEP S TX. TSTMS CONTINUE TO FORM ALONG THIS BOUNDARY WHERE CINH HAS ERODED OWING TO STRONG HEATING/MOISTENING AND CIRCULATION INVOF THE COLD POOL. STORM MERGERS WILL BRIEFLY ENHANCE UPDRAFTS AND STORMS COULD GIVE LOCAL DAMAGING WINDS AND HAIL. ...MID-SOUTH TO FL... UPPER RIDGE AXIS EXTENDS FROM EASTERN AL ALONG THE FL PENINSULA TODAY. AIR MASS UNDER RIDGE IS VERY MOIST/UNSTABLE WITH DEWPOINTS NEAR 70F AND AFTERNOON MLCAPE VALUES AROUND 2000 J/KG. WEAK WINDS ALOFT WILL LIMIT CONVECTIVE ORGANIZATION WITH PULSE-TYPE STORMS MOST LIKELY. HOWEVER...SEA-BREEZE INTERACTIONS AND REMNANT WEAK COLDFRONT MAY HELP FOCUS ACTIVITY WITH THE POTENTIAL FOR WET MICROBURSTS AND HAIL IN STRONGEST CELLS. ..RACY.. 05/28/2006  From swody1 at goshenarc.org Mon May 29 01:04:17 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 28 May 2006 21:04:17 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290102 SWODY1 SPC AC 290100 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0800 PM CDT SUN MAY 28 2006 VALID 290100Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF WEST TX AND WRN OK... ...NRN PLAINS... LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW SSWLY FLOW ACROSS THE HIGH PLAINS WITH A SHORTWAVE TROUGH EMBEDDED IN THE FLOW OVER NERN CO AND SERN WY. AN MCS IS DEVELOPING AHEAD OF THIS FEATURE AND WILL LIKELY CONTINUE NEWD ACROSS WRN AND CNTRL SD THIS EVENING. ALTHOUGH THE MAIN AXIS OF INSTABILITY IS LOCATED WELL EAST OF THE EXPECTED TRACK OF THE MCS...THE STORM COMPLEX SHOULD MOVE INTO INCREASING INSTABILITY HELPING TO SUSTAIN THE CONVECTIVE SYSTEM THROUGH THE OVERNIGHT PERIOD POSSIBLY REACHING ERN ND AND NWRN MN LATE TONIGHT. ALTHOUGH THE MCS IS CURRENTLY IN AN AREA OF WEAK INSTABILITY...THE STRONG VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS IN WRN SD SUGGEST SUPERCELLS WILL BE POSSIBLE. AS THE STORMS MOVE INTO INCREASING INSTABILITY...THE SUPERCELL THREAT MAY INCREASE CONTINUING OVERNIGHT. IN ADDITION...OBJECTIVE ANALYSIS SHOWS A PLUME OF VERY STEEP LAPSE RATES EXTENDING NEWD ACROSS WRN NEB INTO ERN SD. THIS COMBINED WITH STEEP LOW-LEVEL LAPSE RATES SUGGESTS A THREAT FOR LARGE HAIL AND WIND DAMAGE WILL BE ILKLEY WITH THE STRONGER SUPERCELLS AND/OR BOW ECHOES. AN ISOLATED TORNADO THREAT WILL ALSO LIKELY EXIST AS LOW-LEVEL SHEAR PROFILES BECOME MORE FAVORABLE DUE TO A 60 KT LOW-LEVEL JET EXPANDING NWD INTO CNTRL SD LATE THIS EVENING. ...WEST TX AND WRN OK... LATEST WATER VAPOR IMAGERY SHOWS SWLY FLOW IN PLACE ACROSS THE SRN PLAINS. AT THE SFC...A DRYLINE IS LOCATED FROM WRN KS EXTENDING SWD THROUGH THE CNTRL TX PANHANDLE INTO WEST TX ALONG THE ERN EDGE OF THE CAPROCK. SFC DEWPOINTS EAST OF THE DRYLINE ARE IN THE UPPER 50S TO NEAR 60 F WHERE AN AXIS OF MODERATE INSTABILITY IS LOCATED. ISOLATED SEVERE THUNDERSTORMS ARE ONGOING ALONG THE INSTABILITY GRADIENT. CURRENT STORM INTENSITY SHOULD PERSIST THROUGH MOST OF THE EVENING AS SEVERAL MCS CLUSTERS DEVELOP AND MOVE EWD INTO INCREASING INSTABILITY. THE JAYTON TX PROFILER CURRENTLY SHOWS 0-6 KM SHEAR VALUES OF 35-40 KT SUGGESTING THE SUPERCELL THREAT WILL CONTINUE. STEEP LAPSE RATES FROM THE SFC TO MID-LEVELS EXCEED 8.0 C/KM AND THIS SHOULD ENHANCE THE POTENTIAL FOR LARGE HAIL AND ISOLATED WIND DAMAGE POTENTIAL WITH THE STRONGER STORMS. ..BROYLES.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 06:04:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 02:04:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290603 SWODY1 SPC AC 290601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT MON MAY 29 2006 VALID 291200Z - 301200Z ...NO SVR TSTM AREAS FORECAST... ...UPPER MIDWEST/CNTRL AND SRN PLAINS... A SOUTHWEST FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE CNTRL U.S. AS AN UPPER-LEVEL TROUGH MOVES NEWD ACROSS THE NRN PLAINS TODAY. AT THE SFC...A COLD FRONT WILL EXTEND SSWWD FROM CNTRL MN TO CNTRL KS WITH DEWPOINTS EAST OF THE FRONT IN THE MID TO UPPER 60S F. AS SFC TEMPS WARM DURING THE DAY...A MODERATELY TO STRONGLY UNSTABLE UNCAPPED AIRMASS SHOULD BE IN PLACE ALONG AND EAST OF THE FRONTAL ZONE. STORMS SHOULD INITIATE ALONG THE BOUNDARY FIRST IN MN WHERE STRONGER LARGE-SCALE ASCENT IS FORECAST ASSOCIATED WITH THE NRN PLAINS UPPER-TROUGH. AS STORM COVERAGE INCREASES IN THE LATE AFTERNOON...THUNDERSTORM DEVELOPMENT SHOULD OCCUR SWD FROM CNTRL IA ACROSS ERN NEB...NW MO INTO KS AND POSSIBLY NW OK. FORECAST SOUNDINGS THIS AFTERNOON ACROSS THE UPPER MIDWEST SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ACROSS MN AND NRN IA SUGGESTING SUPERCELLS WILL BE LIKELY IN THE AFTERNOON. THE INSTABILITY AND RELATIVELY COOLER AIR ALOFT SHOULD BE FAVORABLE FOR LARGE HAIL WITH THE STRONGER SUPERCELLS. A WIND DAMAGE THREAT WILL ALSO BE LIKELY AND MAY BECOME ENHANCED AS STORM COVERAGE INCREASES AND CELLS MERGE IN THE LATE AFTERNOON. MCS DEVELOPMENT APPEARS LIKELY BY EARLY EVENING AS A LINE OF STORMS WITH LARGE HAIL AND WIND DAMAGE POTENTIAL MOVES EWD INTO WRN WI. FURTHER SOUTH ACROSS THE SRN AND CNTRL PLAINS...STRONG INSTABILITY SHOULD BE PRESENT BY LATE AFTERNOON WITH MLCAPE VALUES ABOVE 3000 J/KG FORECAST ALONG AND AHEAD OF THE BOUNDARY. IN ADDITION...AFTERNOON FORECAST SOUNDINGS SHOW MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. A FEW SUPERCELLS MAY HAVE VERY LARGE HAIL ESPECIALLY WITH STORMS THAT HAVE ACCESS TO LOCALLY STRONG TO EXTREME INSTABILITY. WIND DAMAGE WILL ALSO BE POSSIBLE WITH THE STRONGER STORMS AND MAY CONTINUE OVERNIGHT WITH ANY MCS THAT DEVELOPS AND TRACKS EWD ACROSS THE REGION. ...SRN NEW ENGLAND/MID-ATLANTIC.... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN U.S. TODAY AS A SHORTWAVE TROUGH TOPS THE RIDGE AND MOVES ACROSS NEW ENGLAND. IN RESPONSE...THUNDERSTORM DEVELOPMENT SHOULD OCCUR AHEAD OF THE SHORTWAVE IN THE NRN APPALACHIAN MTNS AND SPREAD SEWD ACROSS SRN NEW ENGLAND INTO THE MID-ATLANTIC STATES IN THE AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW SFC DEWPOINTS IN THE 60S F WHICH SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY. IN ADDITION...0-6 KM SHEAR VALUES ARE FORECAST TO BE THE 30-35 KT RANGE SUGGESTING SUPERCELLS WILL BE POSSIBLE NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. HAIL AND ISOLATED WIND DAMAGE WOULD BE THE MAIN THREAT WITH ANY SUPERCELLS THAT DEVELOP IN THE MID TO LATE AFTERNOON. ..BROYLES/GUYER.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 06:18:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 02:18:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290616 SWODY1 SPC AC 290614 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0114 AM CDT MON MAY 29 2006 VALID 291200Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST...CNTRL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SRN NEW ENGLAND AND THE MID-ATLANTIC STATES... CORRECTED CATEGORICAL OUTLOOK GRAPHIC ...UPPER MIDWEST/CNTRL AND SRN PLAINS... A SOUTHWEST FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE CNTRL U.S. AS AN UPPER-LEVEL TROUGH MOVES NEWD ACROSS THE NRN PLAINS TODAY. AT THE SFC...A COLD FRONT WILL EXTEND SSWWD FROM CNTRL MN TO CNTRL KS WITH DEWPOINTS EAST OF THE FRONT IN THE MID TO UPPER 60S F. AS SFC TEMPS WARM DURING THE DAY...A MODERATELY TO STRONGLY UNSTABLE UNCAPPED AIRMASS SHOULD BE IN PLACE ALONG AND EAST OF THE FRONTAL ZONE. STORMS SHOULD INITIATE ALONG THE BOUNDARY FIRST IN MN WHERE STRONGER LARGE-SCALE ASCENT IS FORECAST ASSOCIATED WITH THE NRN PLAINS UPPER-TROUGH. AS STORM COVERAGE INCREASES IN THE LATE AFTERNOON...THUNDERSTORM DEVELOPMENT SHOULD OCCUR SWD FROM CNTRL IA ACROSS ERN NEB...NW MO INTO KS AND POSSIBLY NW OK. FORECAST SOUNDINGS THIS AFTERNOON ACROSS THE UPPER MIDWEST SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ACROSS MN AND NRN IA SUGGESTING SUPERCELLS WILL BE LIKELY IN THE AFTERNOON. THE INSTABILITY AND RELATIVELY COOLER AIR ALOFT SHOULD BE FAVORABLE FOR LARGE HAIL WITH THE STRONGER SUPERCELLS. A WIND DAMAGE THREAT WILL ALSO BE LIKELY AND MAY BECOME ENHANCED AS STORM COVERAGE INCREASES AND CELLS MERGE IN THE LATE AFTERNOON. MCS DEVELOPMENT APPEARS LIKELY BY EARLY EVENING AS A LINE OF STORMS WITH LARGE HAIL AND WIND DAMAGE POTENTIAL MOVES EWD INTO WRN WI. FURTHER SOUTH ACROSS THE SRN AND CNTRL PLAINS...STRONG INSTABILITY SHOULD BE PRESENT BY LATE AFTERNOON WITH MLCAPE VALUES ABOVE 3000 J/KG FORECAST ALONG AND AHEAD OF THE BOUNDARY. IN ADDITION...AFTERNOON FORECAST SOUNDINGS SHOW MODERATE VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL WILL BE LIKELY. A FEW SUPERCELLS MAY HAVE VERY LARGE HAIL ESPECIALLY WITH STORMS THAT HAVE ACCESS TO LOCALLY STRONG TO EXTREME INSTABILITY. WIND DAMAGE WILL ALSO BE POSSIBLE WITH THE STRONGER STORMS AND MAY CONTINUE OVERNIGHT WITH ANY MCS THAT DEVELOPS AND TRACKS EWD ACROSS THE REGION. ...SRN NEW ENGLAND/MID-ATLANTIC.... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN U.S. TODAY AS A SHORTWAVE TROUGH TOPS THE RIDGE AND MOVES ACROSS NEW ENGLAND. IN RESPONSE...THUNDERSTORM DEVELOPMENT SHOULD OCCUR AHEAD OF THE SHORTWAVE IN THE NRN APPALACHIAN MTNS AND SPREAD SEWD ACROSS SRN NEW ENGLAND INTO THE MID-ATLANTIC STATES IN THE AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW SFC DEWPOINTS IN THE 60S F WHICH SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY. IN ADDITION...0-6 KM SHEAR VALUES ARE FORECAST TO BE THE 30-35 KT RANGE SUGGESTING SUPERCELLS WILL BE POSSIBLE NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. HAIL AND ISOLATED WIND DAMAGE WOULD BE THE MAIN THREAT WITH ANY SUPERCELLS THAT DEVELOP IN THE MID TO LATE AFTERNOON. ..BROYLES.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 13:02:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 09:02:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291301 SWODY1 SPC AC 291259 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 AM CDT MON MAY 29 2006 VALID 291300Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM THE UPPER MS VALLEY INTO THE CENTRAL PLAINS... ...SYNOPSIS... MAIN PATTERN IS MID/UPPER LEVEL TROUGH OVER THE WEST WITH RIDGING OVER THE ERN THIRD OF THE U.S. SURFACE FRONTAL BOUNDARY EXTENDED FROM NWRN MN SSWWD ACROSS SERN SD INTO SWRN KS AND THE OK PANHANDLE. ...CENTRAL MN INTO WRN WI..AND SWD INTO IA... MODELS BRING SEVERAL SHORTWAVE TROUGHS AROUND BASE OF WRN U.S. FULL LATITUDE TROUGH NNEWD INTO THE NRN PLAINS/NRN MN. MUCH OF THE FLOW IS UNIDIRECTIONAL...AND WOULD EXPECT LITTLE MOVEMENT EWD OF FRONTAL BOUNDARY INTO EARLY THIS AFTERNOON. NAM/GFS MOVE THE FRONT INTO ERN MN SSWWD INTO EXTREME SERN NEB BY 2100Z. ASSUME MUCH OF THIS WILL BE DUE TO CONVECTION DEVELOPING ON/JUST BEHIND THE BOUNDARY WHERE THERE WILL BE SOME SHEAR. AHEAD OF THE FRONT...AIR MASS IS EXPECTED TO BECOME VERY UNSTABLE DUE TO STRONG DAYTIME HEATING IN THE MIXED LAYER. MLCAPE ARE PROJECTED TO BE 3000-4000 J/KG FROM CENTRAL MN SSWWD INTO PARTS OF IA WITH SFC-3KM LAPSE RATES AROUND 8.0-8.5C/KM MOSTLY DUE TO HEATING. THIS AREA WILL ALSO BE IN FAVORABLE ENTRANCE REGION OF MID/UPPER LEVEL JET STREAK EXTENDING FROM WRN NEB INTO NERN ND BY TONIGHT ENHANCING UVVS ALONG THE BOUNDARY MOVING INTO VERY UNSTABLE AIR MASS. MAIN THREATS THIS AFTERNOON INTO EARLY TONIGHT WILL BE LARGE HAIL AND DAMAGING WINDS SUPPORTED BY STEEP LOW-MID LEVEL LAPSE RATES. ...AREA FROM IA SWWD THRU KS INTO WRN OK AND ERN TX PANHANDLE... NAM MODEL DEVELOPS STRONG SLOW MOVING CONVECTION/MCS LATE THIS AFTERNOON AND TONIGHT AS A WEAK SHORTWAVE TROUGH MOVES NEWD EMBEDDED IN WEAKER MID LEVEL FLOW OVER SERN AZ INTO SERN CO. DEVELOPMENT WILL BE NEAR FRONTAL BOUNDARY/DRYLINE INTERSECTION. SURFACE PROG INDICATES SELY INTO ELY FLOW INTO AREA OF UPSLOPE FLOW AND DEW POINTS POOLING IN THE MID/UPPER 60S WILL RESULT IN THUNDERSTORM/MCS DEVELOPMENT IN VICINITY OF WEAK LOW OVER NWRN OK/TX PANHANDLE WHERE STEEP LOW/MID LEVEL LAPSE RATES WILL BE AROUND 8C/KM AND MLCAPE WILL BE AROUND 3000 J/KG. POSSIBILITY EXISTS FOR LARGE HAIL AND DOWNBURST WINDS THIS EVENING... DECREASING TONIGHT WITH LOSS OF DAYTIME HEATING. ...PARTS NY INTO MA/CT/RI... REMNANTS OF MCV MENTIONED IN MESOSCALE DISCUSSION 1019 ISSUED AT 1008Z CONTINUES TO MOVE SEWD ACROSS NERN NY STATE THIS MORNING. MORNING RAOB DATA FROM BUF SHOWS SOME MID LEVEL INSTABILITY ASSOCIATED WITH MID LEVEL LAPSE RATES NEAR 7C/KM. ACTIVITY WILL MOVE SEWD THROUGH EARLY THIS AFTERNOON PRODUCING MOSTLY STRONG STORMS WITH SOME SMALL HAIL. ..MCCARTHY/GUYER.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 16:20:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 12:20:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291612 SWODY1 SPC AC 291610 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1110 AM CDT MON MAY 29 2006 VALID 291630Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MIDWEST STATES AND CENTRAL PLAINS... LARGE UPPER RIDGE REMAINS OVER THE EASTERN UNITED STATES TODAY...WHILE SERIES OF SHORTWAVE TROUGHS ROTATE AROUND LONGWAVE TROUGH OVER THE WESTERN STATES. MAIN SURFACE BAROCLINIC ZONE HAS SHIFTED EASTWARD INTO PARTS OF MN/IA/NEB/KS TODAY...WHERE POTENTIAL EXISTS FOR SCATTERED THUNDERSTORMS. OTHER ACTIVITY WILL ONCE AGAIN OCCUR ALONG DRYLINE OVER PARTS OF OK/TX. FINALLY...STRONG INSTABILITY AND AMPLE MOISTURE MAY LEAD TO ISOLATED THUNDERSTORMS OVER PARTS OF THE MS/OH/TN VALLEYS AND SOUTHEAST STATES. ...UPPER MIDWEST INTO CENTRAL PLAINS... MORNING SURFACE ANALYSIS SHOWS FRONT EXTENDING FROM WESTERN MN INTO CENTRAL KS AND THE TX PANHANDLE. AIR MASS ALONG AND EAST OF FRONT REMAINS MOIST AND MODERATELY UNSTABLE WITH DEWPOINTS IN THE UPPER 60S AND AFTERNOON MLCAPE VALUES EXPECTED TO EXCEED 3000 J/KG. MORNING SOUNDINGS AND MODEL GUIDANCE SUGGEST THAT CAP HAS WEAKENED SINCE YESTERDAY...WHICH SHOULD ALLOW SCATTERED THUNDERSTORM DEVELOPMENT ALONG THE FRONT THIS AFTERNOON AND EVENING. HOWEVER...MAIN UPPER FORCING AND VERTICAL SHEAR IS WELL WEST OF BOUNDARY EXCEPT OVER MN. SHEAR IS SUFFICIENT FOR SUPERCELLS AND BOWS OVER PARTS OF CENTRAL/NORTHERN MN...WHERE HIGHER SEVERE PROBABILITIES HAVE BEEN MAINTAINED. HOWEVER... ACTIVITY WILL BE RATHER DISORGANIZED FARTHER SOUTH UNLESS UPSCALE ORGANIZATION CAN OCCUR THIS EVENING AS CONVECTIVE CLUSTERS GROW. DEGREE OF INSTABILITY WILL POSE A THREAT OF LARGE HAIL AND DAMAGING WINDS IN STRONGER CELLS. ...OK/TX... SURFACE DRYLINE IS EXPECTED TO BECOME ESTABLISHED THIS AFTERNOON FROM THE EASTERN TX PANHANDLE INTO THE TRANSPECOS AREA. WEAK FLOW ALOFT...COMBINED WITH RELATIVELY STRONG INSTABILITY...WILL ONCE AGAIN RESULT IN ISOLATED STRONG/SEVERE STORMS. HIGH-BASED CELLS WILL BE CAPABLE OF DAMAGING WINDS AND HAIL FOR A FEW HOURS THIS EVENING BEFORE WEAKENING. ...NORTHEAST STATES... WATER VAPOR IMAGERY SHOWS WELL-DEFINED SHORTWAVE TROUGH TRACKING SOUTHEASTWARD ACROSS NY. WEAK FORCING FOR UPWARD VERTICAL MOTION ALONG THE SOUTHERN PERIPHERY OF THIS FEATURE WILL LIKELY AID IN THE DEVELOPMENT OF ISOLATED AFTERNOON THUNDERSTORMS FROM EASTERN NY/PA SOUTHWARD INTO THE DELMARVA REGION. AIR MASS IN THIS REGION IS MODERATELY UNSTABLE WITH MLCAPE VALUES UP TO 1500 J/KG...ALONG WITH SUFFICIENT NORTHERLY FLOW ALOFT FOR SOME CONVECTIVE ORGANIZATION. AREAL COVERAGE OF STRONGER CELLS REMAINS IN QUESTION DUE TO WEAK FORCING...SO WILL MAINTAIN ONLY LOW SEVERE PROBABILITIES AT THIS TIME. ...MID MS AND TN VALLEYS INTO FL... WATER VAPOR IMAGERY SHOWS AXIS OF MID LEVEL MOISTURE EXTENDING FROM PARTS OF IL/IND ACROSS TN/AL INTO SOUTH FL. THIS IS THE SAME AXIS IN WHICH SCATTERED INTENSE STORMS DEVELOPED YESTERDAY. STRONG DAYTIME HEATING IN THIS ZONE...COUPLED WITH DEWPOINTS NEAR 70F MAY AGAIN PROVE SUFFICIENT FOR WEAKLY ORGANIZED MULTICELL STORMS CAPABLE OF WET MICROBURSTS AND HAIL. SEA-BREEZE INTERACTIONS MAY ALSO ENHANCE STORMS OVER THE WESTERN COAST OF THE FL PENINSULA. ..HART/LEVIT.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 20:05:15 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 16:05:15 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292003 SWODY1 SPC AC 292002 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0302 PM CDT MON MAY 29 2006 VALID 292000Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/TX... ...UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/WRN N TX... STRONG/SEVERE THUNDERSTORMS CONTINUE TO INCREASE AHEAD OF COLD FRONT OVER MN ATTM...WHERE VERY UNSTABLE AIRMASS IS INDICATED. THOUGH STRONGEST FLOW ALOFT SHOULD REMAIN ON THE COOL SIDE OF THE BOUNDARY...SHEAR REMAINS SUFFICIENT GIVEN DEGREE OF INSTABILITY FOR ORGANIZED/LOCALLY INTENSE STORMS. THREAT FOR HAIL AND DAMAGING WINDS WILL CONTINUE INTO THIS EVENING WHILE SHIFTING EWD INTO WI AND WRN UPPER MI...AS STORMS REMAIN ORGANIZED IN A QUASI-LINEAR FASHION. FURTHER S ALONG FRONT...WEAKER WIND FIELD EXISTS. HOWEVER...EXPECT SCATTERED STORMS TO DEVELOP SWD ALONG FRONT WITHIN MARGINALLY-UNSTABLE AIRMASS. LOCALLY STRONG/SEVERE STORMS ARE EXPECTED...ALONG WITH THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL. STORMS WILL LIKELY CONTINUE THROUGH MUCH OF THE PERIOD -- PARTICULARLY ACROSS PARTS OF KS/OK AND VICINITY...AS LOW-LEVEL JET DEVELOPS THIS EVENING. OVERALL SEVERE THREAT SHOULD DIMINISH WITH TIME HOWEVER THROUGH THE END OF THE PERIOD. ...PARTS OF SRN NEW ENGLAND INTO NJ/ERN PA... ISOLATED THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THIS REGION WHERE AIRMASS HAS DESTABILIZED -- PARTICULARLY ALONG AND W OF THE HUDSON VALLEY. THOUGH A STRONGER CELL OR TWO COULD PRODUCE LOCALLY GUSTY WINDS OR SMALL HAIL...OVERALL CONVECTIVE THREAT APPEARS TO BE QUITE LOW. ...TN VALLEY INTO THE CENTRAL GULF COAST REGION... DIURNAL/PULSE-TYPE THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND EARLY EVENING ACROSS THIS REGION...BENEATH UPPER HIGH WHERE WEAK FLOW BUT MODERATE INSTABILITY EXISTS. THREAT FOR LOCALLY GUSTY WINDS/HAIL WILL PERSIST WITH STRONGER STORMS...RAPIDLY DIMINISHING THROUGH THE EVENING. ...S FL... THUNDERSTORMS HAVE DEVELOPED ACROSS S FL NEAR SEA BREEZE BOUNDARIES THIS AFTERNOON...IN AIRMASS FEATURING MODERATE INSTABILITY BUT WEAK SHEAR. THOUGH A FEW PULSE-TYPE SEVERE STORMS WILL REMAIN POSSIBLE INTO THIS EVENING...OVERALL THREAT WILL REMAIN LIMITED/TRANSIENT. ..GOSS.. 05/29/2006  From swody1 at goshenarc.org Mon May 29 21:26:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 17:26:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292122 SWODY1 SPC AC 292121 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0421 PM CDT MON MAY 29 2006 VALID 292000Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/TX... CORRECTED TO CHANGE MARGINAL TO MODERATE IN SECOND PARAGRAPH ...UPPER MS VALLEY SSWWD INTO PARTS OF KS/OK/WRN N TX... STRONG/SEVERE THUNDERSTORMS CONTINUE TO INCREASE AHEAD OF COLD FRONT OVER MN ATTM...WHERE VERY UNSTABLE AIRMASS IS INDICATED. THOUGH STRONGEST FLOW ALOFT SHOULD REMAIN ON THE COOL SIDE OF THE BOUNDARY...SHEAR REMAINS SUFFICIENT GIVEN DEGREE OF INSTABILITY FOR ORGANIZED/LOCALLY INTENSE STORMS. THREAT FOR HAIL AND DAMAGING WINDS WILL CONTINUE INTO THIS EVENING WHILE SHIFTING EWD INTO WI AND WRN UPPER MI...AS STORMS REMAIN ORGANIZED IN A QUASI-LINEAR FASHION. FURTHER S ALONG FRONT...WEAKER WIND FIELD EXISTS. HOWEVER...EXPECT SCATTERED STORMS TO DEVELOP SWD ALONG FRONT WITHIN MODERATELY-UNSTABLE AIRMASS. LOCALLY STRONG/SEVERE STORMS ARE EXPECTED...ALONG WITH THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL. STORMS WILL LIKELY CONTINUE THROUGH MUCH OF THE PERIOD -- PARTICULARLY ACROSS PARTS OF KS/OK AND VICINITY...AS LOW-LEVEL JET DEVELOPS THIS EVENING. OVERALL SEVERE THREAT SHOULD DIMINISH WITH TIME HOWEVER THROUGH THE END OF THE PERIOD. ...PARTS OF SRN NEW ENGLAND INTO NJ/ERN PA... ISOLATED THUNDERSTORMS MAY DEVELOP ACROSS PARTS OF THIS REGION WHERE AIRMASS HAS DESTABILIZED -- PARTICULARLY ALONG AND W OF THE HUDSON VALLEY. THOUGH A STRONGER CELL OR TWO COULD PRODUCE LOCALLY GUSTY WINDS OR SMALL HAIL...OVERALL CONVECTIVE THREAT APPEARS TO BE QUITE LOW. ...TN VALLEY INTO THE CENTRAL GULF COAST REGION... DIURNAL/PULSE-TYPE THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND EARLY EVENING ACROSS THIS REGION...BENEATH UPPER HIGH WHERE WEAK FLOW BUT MODERATE INSTABILITY EXISTS. THREAT FOR LOCALLY GUSTY WINDS/HAIL WILL PERSIST WITH STRONGER STORMS...RAPIDLY DIMINISHING THROUGH THE EVENING. ...S FL... THUNDERSTORMS HAVE DEVELOPED ACROSS S FL NEAR SEA BREEZE BOUNDARIES THIS AFTERNOON...IN AIRMASS FEATURING MODERATE INSTABILITY BUT WEAK SHEAR. THOUGH A FEW PULSE-TYPE SEVERE STORMS WILL REMAIN POSSIBLE INTO THIS EVENING...OVERALL THREAT WILL REMAIN LIMITED/TRANSIENT. ..GOSS.. 05/29/2006  From swody1 at goshenarc.org Tue May 30 01:02:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 29 May 2006 21:02:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300100 SWODY1 SPC AC 300059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT MON MAY 29 2006 VALID 300100Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN AND CNTRL PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PART OS NERN IL AND FAR NW IND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SERN AND SCNTRL MO... ...UPPER MIDWEST/CNTRL AND SRN PLAINS... LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-RIDGE IN PLACE ACROSS THE ERN U.S. WITH SOUTHWEST FLOW PRESENT ACROSS THE PLAINS AND UPPER MIDWEST. AT THE SFC...A COLD FRONT IS LOCATED FROM ERN MN EXTENDING SSWWD INTO SERN NEB. SFC DEWPOINTS EAST OF THE BOUNDARY ARE IN THE MID TO UPPER 60S F PRODUCING VERY UNSTABLE AIR WITH MLCAPE VALUES AROUND 2500 J/KG. A LINEAR MCS IS CURRENTLY ONGOING ACROSS NE MN AND NWRN WI AND THE MCS SHOULD CONTINUE EWD ACROSS THE ARROWHEAD OF MN AND INTO NRN/CNTRL WI LATE THIS EVENING. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES WHICH COMBINED WITH THE MODERATE TO STRONG INSTABILITY SHOULD SUSTAIN THE SUPERCELL THREAT WITH THE STRONGER CELLS EMBEDDED IN THE LINE. THE SEVERE THREAT SHOULD REMAIN MORE ISOLATED ACROSS IA AND SE NEB DUE TO WEAKER LOW-LEVEL FLOW IN THAT AREA. FURTHER SOUTH ACROSS THE CNTRL AND SRN PLAINS...A NEARLY STATIONARY FRONT EXISTS FROM CNTRL KS SWWD INTO WEST TX. SCATTERED STORMS ARE ONGOING ALONG AND JUST AHEAD OF THE FRONT AND SHOULD CONTINUE EWD INTO THE STRONG INSTABILITY LATE THIS EVENING. THE GREATEST CONVECTIVE COVERAGE SHOULD BE ACROSS NRN OK AND SRN KS AS THE LOW-LEVEL JET STRENGTHENS. FORECAST SOUNDINGS ACROSS THE REGION SHOW MODERATE VERTICAL SHEAR PROFILES ALONG THE BOUNDARY FROM NRN OK TO NRN KS SUGGESTING SUPERCELLS WILL BE LIKELY. IN ADDITION...STEEP MID-LEVEL LAPSE RATES IN PLACE WILL BE FAVORABLE FOR LARGE HAIL WITH WIND DAMAGE ALSO POSSIBLE AS STORMS MERGE AND MCS DEVELOPMENT OCCURS LATE THIS EVENING. ...ERN MO/NERN IL... SEVERAL MCS CLUSTERS ARE CURRENTLY ONGOING ALONG THE WRN EDGE OF AN ERN U.S. UPPER-LEVEL RIDGE IN NRN IL AND ERN MO. THE STORMS COMPLEXES ARE LOCATED IN A MODERATELY UNSTABLE AIRMASS AND SHOULD CONTINUE THROUGH THE LATE EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW RELATIVELY WEAK SHEAR PROFILES IN PLACE...AN AXIS OF STEEP LOW-LEVEL LAPSE RATES EXIST FROM ERN MO EXTENDING NEWD INTO CNTRL IL AS SHOWN ON OBJECTIVE ANALYSIS. THIS COMBINED WITH THE MODERATE INSTABILITY SHOULD BE ENOUGH TO CONTINUE AN ISOLATED SEVERE THREAT ACROSS ERN MO AND NERN IL FOR AT LEAST A FEW MORE HOURS. ..BROYLES.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 05:57:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 01:57:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300555 SWODY1 SPC AC 300554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT TUE MAY 30 2006 VALID 301200Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...CNTRL PLAINS...NRN OZARKS AND LOWER OH VALLEY... ...TX PANHANDLE/WEST TX/WRN OK/SE CO/WRN KS... A WEAK FLOW PATTERN WILL REMAIN IN PLACE ACROSS THE PLAINS TODAY AS A SUBTLE SHORTWAVE TROUGH MOVES NEWD ACROSS THE HIGH PLAINS IN STRONGER FLOW. AT THE SFC...A COLD FRONT SHOULD BE LOCATED ACROSS SERN CO...THE NRN TX PANHANDLE EXTENDING ENEWD INTO SRN KS. SOUTH OF THE FRONT...SFC DEWPOINTS FROM THE UPPER 50S F TO THE UPPER 60S F SHOULD RESULT IN MODERATE TO STRONG INSTABILITY BY AFTERNOON. STORMS SHOULD INITIATE ALONG THE NRN EDGE OF THE INSTABILITY AXIS WITH SEVERAL CONVECTIVE CLUSTERS MOVING SEWD ACROSS SERN CO...THE TX PANHANDLE AND WRN OK. FORECAST SOUNDINGS ACROSS THE REGION LATE THIS AFTERNOON SHOW MODERATE TO STRONG VERTICAL SHEAR PROFILES ALONG THE FRONTAL BOUNDARY WITH 0-6 KM SHEAR VALUES IN THE 35 TO 45 KT RANGE. THIS COMBINED WITH THE INSTABILITY AND STEEP LAPSE RATES IN PLACE SHOULD BE FAVORABLE FOR SUPERCELLS WITH LARGE HAIL AND ISOLATED WIND DAMAGE. LOW-LEVEL SHEAR PROFILES ARE FORECAST TO BACK AND INCREASE IN THE EARLY EVENING FROM THE WEST TX CAPROCK INTO SWRN OK AND MAY RESULT IN AN ISOLATED TORNADO THREAT WITH THE STRONGER SUPERCELLS. ALTHOUGH THE SEVERE THREAT SHOULD GRADUALLY DROP OFF OVERNIGHT...MODEL FORECASTS ARE GENERAL AGREEMENT DRIVING AN MCS SEWD ACROSS THE LOW-ROLLING PLAINS AND ANOTHER MCS ESEWD ACROSS SWRN KS. ...CNTRL PLAINS/NRN OZARKS/LOWER OH VALLEY... A WEAK FLOW PATTERN WILL REMAIN IN PLACE TODAY AS A COLD FRONT MOVES SLOWLY SWD ACROSS ERN KS...THE NRN OZARKS AND SRN GREAT LAKES. SOUTH OF THE BOUNDARY...MODERATE TO STRONG INSTABILITY SHOULD DEVELOP BY AFTERNOON WITH MLCAPE VALUES RANGING FROM 2000-3000 J/KG. SCATTERED THUNDERSTORMS SHOULD DEVELOP ALONG AND AHEAD OF THE BOUNDARY...SPREAD SEWD ACROSS THE REGION IN THE LATE AFTERNOON AND EARLY EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW RELATIVELY WEAK SHEAR PROFILES...THE AMOUNT OF INSTABILITY SUGGESTS THAT PULSE SEVERE STORMS WILL BE LIKELY. WIND DAMAGE AND HAIL WILL BE POSSIBLE WITH THE STRONGER STORMS ESPECIALLY WHERE LOW-LEVEL LAPSE RATES ARE LOCALLY MAXIMIZED. ...WRN NY/WRN PA AND UPPER 0H VALLEY... AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE ERN SEABOARD AS A SHORTWAVE TROUGH MOVES ACROSS THE TOP OF THE RIDGE INTO NEW ENGLAND. AT THE SFC...A WARM FRONT SHOULD BE IN PLACE ACROSS ERN NY WITH SFC DEWPOINTS WEST OF THE BOUNDARY IN THE 60S F. THIS SHOULD RESULT IN POCKETS OF MODERATE INSTABILITY BY AFTERNOON WITH SCATTERED THUNDERSTORMS INITIATING IN THE HIGHER TERRAIN. FORECAST SOUNDINGS SHOW WEAK SHEAR PROFILES SUGGESTING STORMS WILL REMAIN PULSE OR MULTICELLULAR IN NATURE. HOWEVER...A MARGINAL THREAT FOR WIND DAMAGE AND HAIL WILL BE POSSIBLE ESPECIALLY NEAR AREAS OF LOCALLY MAXIMIZED INSTABILITY. ..BROYLES.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 12:45:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 08:45:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301243 SWODY1 SPC AC 301242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT TUE MAY 30 2006 VALID 301300Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS CONTINUES FROM THE CENTRAL/SRN HIGH PLAINS NEWD INTO THE UPPER GREAT LAKES.... ...SYNOPSIS... LATEST WATER VAPOR IMAGERY CONTINUES TO ILLUSTRATE MID/UPPER LEVEL TROUGH OVER THE WRN U.S. ALONG 114W. LAST IN A SERIES OF EMBEDDED MINOR SHORTWAVES LOOK TO BE OVER NRN UT THIS MORNING AND WILL BE LIFTING NEWD TODAY. MODELS INDICATE THAT AS THIS HAPPENS TROUGH WILL BECOME LESS AMPLIFIED AS ERN U.S. RIDGE HOLD ITS POSITION OVER THE ERN OHIO AND TENNESSEE VALLEYS. SURFACE ANALYSIS THIS MORNING HAS BECOME A STATE OF DISARRAY THANKS TO THE NUMEROUS CLUSTERS OF CONVECTION THAT HAVE BEEN OCCURRING FROM WI THROUGH IA/MO INTO KS...OK AND WEST TEXAS. WHAT IS LEFT OF A QUASISTATIONARY FRONT EXTENDS FROM ERN UPPER MI SWWD INTO SERN MN BEFORE THE PLETHORA OF BOUNDARIES EXTEND FROM CENTRAL IA INTO NERN KS INTO THE EDWARDS PLATEAU REGION OF TX. ...PARTS OF ERN WI SWWD INTO ERN KS... WEAKENING FRONTAL BOUNDARY AND THE NUMEROUS CONVECTIVE BOUNDARIES WILL CONTINUE TO BE FOCUS OF CONVECTION AND ITS REDEVELOPMENT THIS AFTERNOON AND EVENING. AIR MASS ACROSS THE SOUTHERN HALF OF THE PLAINS EWD INTO THE MISSISSIPPI AND OHIO VALLEYS REMAIN POTENTIALLY VERY UNSTABLE WITH MUCAPES BETWEEN 2500 AND 4000 J/KG. THUS...AS DAYTIME HEATING TAKES PLACE THROUGH THIS AFTERNOON...STRONG/SEVERE THUNDERSTORMS WILL DEVELOP WITHIN THIS AIR MASS AND NEAR AREAS CLOSE TO THE OLD CONVECTIVE BOUNDARIES. SOME LARGE HAIL AND DOWNBURST WINDS WILL BE THE MAIN THREAT ACROSS THIS LARGE AREA MAINLY THIS AFTERNOON AND EARLY TONIGHT. ...CENTRAL AND SOUTHERN HIGH PLAINS INTO CENTRAL KS... DUE TO THE CONVECTIVE BOUNDARIES AND WRN U.S. TROUGHING...SURFACE WINDS ARE SELY FOR THE MOST PART ACROSS THE SOUTHERN HALF OF THE PLAINS THIS MORNING AIDING IN THE UPSLOPE FLOW THAT HAS LEAD TO CONVECTION OVER PARTS OF ERN CO AND WRN KS. AGAIN THE BOUNDARIES FROM THIS CONVECTION WILL PLAY ROLE IN INITIATION OF NEW CONVECTION THIS EVENING AND TONIGHT AS LOW LEVEL JET COUPLES WITH MOIST BOUNDARY LAYER. SLY LOW LEVEL JET AROUND 30 KT WILL EXTEND THRU THE SRN HIGH PLAINS ENHANCING WAA/LIFT NEAR THE BOUNDARY FORECAST TO BE E-W ACROSS THE CENTRAL TX PANHANDLE. IN ADDITION...NAM MODELS DEPICTS A SHORTWAVE TROUGH THAT WILL ADVANCE EWD TONIGHT AHEAD OF RELAXING WRN U.S. TROUGH. CONTINUED CONVERGENCE NEAR THE BOUNDARY ENHANCED BY UPSLOPE FLOW COMBINED WITH THIS TROUGH WILL LEAD TO DEVELOPMENT OF MCS TONIGHT OVER PARTS OF ERN CO/SWRN KS INTO THE OK/TX PANHANDLES. FORECAST SOUNDINGS SHOW FAVORABLE PROFILES AND LOW LEVEL SHEAR FOR ISOLATED TORNADOES WITH SOME OF THE DEVELOPING STORMS...CLUSTERING INTO THE MCS WITH THE MAIN THREAT BECOMING HAIL AND DAMAGING WINDS INTO EARLY TONIGHT. ...ERN GREAT LAKES INTO PARTS OF NEW ENGLAND... SECOND IN A SERIES OF WEAK SHORTWAVES HAS TURNED ANTICYCLONICALLY AROUND RIDGE THAT EXTENDS NWD THROUGH THE ERN GREAT LAKES. THIS BROUGHT SOME ISOLATED THUNDERSTORMS TO PARTS OF UPSTATE NY OVERNIGHT. ANOTHER SHORTWAVE IS POISED OVER SERN ONTARIO/SWRN QUEBEC AND IS EXPECTED TO MOVE SEWD THROUGH NERN NY STATE INTO NEW HAMPSHIRE LATER TODAY AND TONIGHT. THUNDERSTORMS COULD OCCUR ONCE AGAIN PRODUCING STRONG WINDS AND SOME HAIL. ...CENTRAL AND SRN FL PENINSULA... 06Z RUN OF THE NAM DEPICTED DEVELOPMENT THIS AFTERNOON OF E TO W MOVING SEA BREEZE BOUNDARY ACROSS PARTS OF THE CENTRAL PENINSULA TOWARDS AREAS FROM TPA SWD THRU FMY AND SRQ THIS AFTERNOON. GIVEN THAT SOUNDINGS SHOW LOW LEVEL LAPSE RATES NEAR 9C/KM BEFORE THE BOUNDARY MOVES INTO AREA...SOME OF THESE STORMS COULD PRODUCE SOME STRONG GUSTY WINDS. ..MCCARTHY.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 16:37:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 12:37:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301629 SWODY1 SPC AC 301627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT TUE MAY 30 2006 VALID 301630Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE CENTRAL AND SOUTHERN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE UPPER MS VALLEY... LARGE UPPER RIDGE CONTINUES TO DOMINATE THE WEATHER OVER MUCH OF THE EASTERN HALF OF THE UNITED STATES TODAY...WITH BROAD/FLAT TROUGH OVER THE WEST AND NORTHWEST FLOW OVER NEW ENGLAND. WIDESPREAD MOIST/UNSTABLE AIR SHOULD LEAD TO NUMEROUS SHOWERS AND THUNDERSTORMS TODAY FROM THE PLAINS INTO THE MIDWEST/GREAT LAKES REGION AND NORTHEAST...AS WELL AS THE MS/TN VALLEYS AND SOUTH FL. MANY OF THESE AREAS WILL HAVE A RISK OF VERY ISOLATED PULSE-TYPE SEVERE STORMS. THE MOST ORGANIZED SEVERE THREAT WILL BE IN THE CENTRAL/SOUTHERN PLAINS. ...CO/NM/KS/OK/TX... SOUTHERN FRINGE OF STRONGER SOUTHWESTERLY MID LEVEL WINDS WILL BE MAINTAINED TODAY ACROSS PARTS OF NM/WEST TX...WITH 20-30 KNOT 500MB FLOW EXPECTED THIS AFTERNOON. LOW LEVEL WINDS ARE BACKED TO SOUTHEASTERLY ACROSS THIS REGION...TRANSPORTING RICHER MOISTURE WESTWARD INTO THE FOOTHILLS AND HIGHER TERRAIN OF EASTERN NM/CO. STRONG HEATING IN THIS REGION WILL LIKELY RESULT IN SCATTERED THUNDERSTORM ACTIVITY DURING THE MID/LATE AFTERNOON. SUFFICIENT CAPE AND VEERING WINDS WITH HEIGHT SUGGEST A POTENTIAL FOR SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. ENHANCED UPSLOPE NEAR THE PALMER/RATON RIDGES MAY AID DEVELOPMENT. OTHER HIGH-BASED STORMS ARE LIKELY IN DEEP MIXED BOUNDARY LAYER SOUTHWARD INTO WEST TX. THIS ACTIVITY WILL SPREAD SLOWLY EASTWARD THIS EVENING INTO AN INCREASINGLY MORE MOIST/UNSTABLE AND MORE STRONGLY SHEARED ENVIRONMENT. THREAT OF SUPERCELLS WILL BE MAINTAINED UNTIL AFTER DARK...WITH ISOLATED TORNADOES POSSIBLE OVER THE NORTHERN TX PANHANDLE AND SOUTHERN KS WHERE STRONGEST VERTICAL SHEAR PROFILES ARE ANTICIPATED. MCS MAY FORM OVERNIGHT...SPREADING INTO CENTRAL KS AND NORTHWEST OK. ...CO/WY... WEAK UPSLOPE FLOW PATTERN WILL BE PRESENT TODAY INTO NORTHEAST CO AND EASTERN WY...WITH DEWPOINTS IN THE 40S AND FULL SUNSHINE. FORECAST SOUNDINGS FOR THIS AFTERNOON IN THIS AREA SHOW FAVORABLE DEEP LAYER SHEAR AND STEEP LAPSE RATES...ALONG WITH MUCAPE AROUND 500 J/KG. SCATTERED CONVECTION IS EXPECTED TO FORM OVER THE FOOTHILLS OF THE FRONT RANGE AND POSSIBLY THE BLACK HILLS...AND SPREAD SLOWLY EASTWARD. A FEW SUPERCELLS ARE POSSIBLE WITH A RISK OF HAIL AND GUSTY WINDS. SEVERE ACTIVITY IS EXPECTED TO REMAIN RATHER ISOLATED. ...UPPER MS VALLEY AND GREAT LAKES REGION... VISIBLE SATELLITE AND RADAR IMAGERY SHOW SCATTERED THUNDERSTORMS ACROSS MUCH OF IA/WI/MI THIS MORNING. THIS TREND IS LIKELY TO CONTINUE THROUGH THE AFTERNOON AS MCV FROM OVERNIGHT CONVECTION TRACKS FROM IA ACROSS WI. THREAT OF IS0LATED SEVERE STORMS IS EXPECTED THIS AFTERNOON ACROSS PARTS OF IA/IL AND SOUTHERN WI. PLEASE REFER TO MESOSCALE DISCUSSION NUMBER 1029 FOR FURTHER DETAILS. ...IL/IN/KY/TN/AL... PATTERN IS VERY SIMILAR TO LAST TWO DAYS...WITH AMPLE LOW LEVEL MOISTURE IN PLACE ACROSS THIS REGION AND STRONG DAYTIME HEATING. MLCAPE VALUES OVER 3000 J/KG THROUGHOUT THIS AREA WILL LEAD TO SCATTERED THUNDERSTORMS BY MID AFTERNOON. VERTICAL SHEAR IS VERY WEAK...SUGGESTING MULTICELL OR PULSE-TYPE SEVERE ACTIVITY IS POSSIBLE. WET MICROBURSTS AND MARGINAL HAIL ARE THE MOST LIKELY THREATS. ACTIVITY SHOULD DIMINISH SHORTLY AFTER SUNSET. ...NY/PA/NJ... MORNING SURFACE ANALYSIS SHOWS POCKET OF VERY MOIST AND POTENTIALLY UNSTABLE AIR REMAINING ACROSS PARTS OF NY/PA. EARLY CU DEVELOPMENT OVER THIS REGION SUGGESTS THE THREAT OF SCATTERED AFTERNOON THUNDERSTORMS. VERTICAL SHEAR IS WEAK...WITH 500MB WIND SPEEDS FORECAST TO BE ONLY 5-10 KNOTS. HOWEVER...DEGREE OF INSTABILITY AND WARM LOW LEVEL TEMPERATURES /19C AT 850MB/ SUGGESTS A THREAT OF ISOLATED PULSE-TYPE SEVERE STORMS CAPABLE OF GUSTY WINDS AND HAIL. OVERALL COVERAGE OF SEVERE STORMS SHOULD BE LIMITED BY WEAK SHEAR...SO WILL ONLY MAINTAIN LOW SEVERE PROBABILITIES. ...FL... DEEP NORTHEASTERLY FLOW ACROSS THE FL PENINSULA SHOULD FOCUS AFTERNOON THUNDERSTORM DEVELOP ALONG THE WESTERN/SOUTHERN SEA-BREEZE TODAY. VERY MOIST/UNSTABLE AIR MASS SUGGESTS A POTENTIAL FOR GUSTY WINDS AND HAIL IN STRONGEST CELLS. ORGANIZED SEVERE STORMS ARE NOT ANTICIPATED TODAY. ..HART/GRAMS.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 20:04:49 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 16:04:49 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302002 SWODY1 SPC AC 302001 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0301 PM CDT TUE MAY 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN IA/SRN WI/NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN NY AND VICINITY... ...PARTS OF THE CENTRAL AND SRN PLAINS... STORMS CONTINUE TO DEVELOP WITHIN MODERATELY-UNSTABLE AIRMASS OVER PARTS OF KS/OK...AND STORM INITIATION IS NOW OCCURRING WWD ACROSS THE HIGH PLAINS INTO ERN CO/NERN NM WHERE DRIER BOUNDARY LAYER/MORE MARGINAL INSTABILITY EXISTS. WITH ELY COMPONENT TO THE LOW-LEVEL FLOW BENEATH 20 TO 30 KT MID-LEVEL WSWLYS...SHEAR SUFFICIENT FOR ORGANIZED/ROTATING STORMS EXISTS. ALONG WITH THREAT FOR HAIL AND LOCALLY-DAMAGING WINDS NOW EVIDENT ACROSS PARTS OF KS/OK...SEVERE THREAT -- MAINLY IN THE FORM OF LOCALLY-DAMAGING WIND GUSTS -- SHOULD ALSO INCREASE ACROSS THE HIGH PLAINS OVER THE NEXT FEW HOURS. AS SELY LOW-LEVEL JET DEVELOPS ACROSS W TX/WRN OK/WRN KS INTO ERN PORTIONS OF CO/NM...EXPECT ONE OR MORE MCS TO EVOLVE AND ROLL SEWD ACROSS THE HIGH PLAINS...WITH LIMITED SEVERE THREAT POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...PARTS OF THE NORTHEAST... DESPITE WEAK SHEAR...MEAN-LAYER CAPE AS HIGH AS 3000 J/KG IS CONTRIBUTING TO A CLUSTER OF THUNDERSTORMS ACROSS ERN NY ATTM...WITH OTHER/MORE ISOLATED STORMS DEVELOPING ACROSS PARTS OF VT/NY/PA SWD INTO NRN VA. DUE TO PERSISTENCE OF STORMS...COLD POOL APPEARS TO BE DEVELOPING WITH THE STORM CLUSTER OVER E CENTRAL/NERN NY NEAR AND W OF GFL /GLEN FALLS NY/...WHICH IS RESULTING IN SOME MESOSCALE ORGANIZATION. THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL WILL CONTINUE ACROSS THIS AREA...PARTICULARLY WITH THE MORE ORGANIZED CLUSTER OF STORMS. ...UPPER MIDWEST... WEAK VORT MAX WILL CONTINUE DRIFTING NWD ACROSS SRN WI...WHILE THUNDERSTORMS PERSIST INVOF THIS FEATURE. THOUGH DEEP-LAYER WIND FIELD REMAINS WEAK...MODERATE INSTABILITY WILL CONTRIBUTE TO A LIMITED HAIL/WIND THREAT WITH STRONGER STORMS INVOF VORT MAX. THREAT SHOULD DIMINISH THIS EVENING AS AIRMASS STABILIZES. ..GOSS.. 05/30/2006  From swody1 at goshenarc.org Tue May 30 20:15:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 30 May 2006 16:15:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302012 SWODY1 SPC AC 302011 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0311 PM CDT TUE MAY 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL AND SRN PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF ERN IA/SRN WI/NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN NY AND VICINITY... CORRECTED TO REMOVE SEE TEXT LABEL FROM FL ...PARTS OF THE CENTRAL AND SRN PLAINS... STORMS CONTINUE TO DEVELOP WITHIN MODERATELY-UNSTABLE AIRMASS OVER PARTS OF KS/OK...AND STORM INITIATION IS NOW OCCURRING WWD ACROSS THE HIGH PLAINS INTO ERN CO/NERN NM WHERE DRIER BOUNDARY LAYER/MORE MARGINAL INSTABILITY EXISTS. WITH ELY COMPONENT TO THE LOW-LEVEL FLOW BENEATH 20 TO 30 KT MID-LEVEL WSWLYS...SHEAR SUFFICIENT FOR ORGANIZED/ROTATING STORMS EXISTS. ALONG WITH THREAT FOR HAIL AND LOCALLY-DAMAGING WINDS NOW EVIDENT ACROSS PARTS OF KS/OK...SEVERE THREAT -- MAINLY IN THE FORM OF LOCALLY-DAMAGING WIND GUSTS -- SHOULD ALSO INCREASE ACROSS THE HIGH PLAINS OVER THE NEXT FEW HOURS. AS SELY LOW-LEVEL JET DEVELOPS ACROSS W TX/WRN OK/WRN KS INTO ERN PORTIONS OF CO/NM...EXPECT ONE OR MORE MCS TO EVOLVE AND ROLL SEWD ACROSS THE HIGH PLAINS...WITH LIMITED SEVERE THREAT POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. ...PARTS OF THE NORTHEAST... DESPITE WEAK SHEAR...MEAN-LAYER CAPE AS HIGH AS 3000 J/KG IS CONTRIBUTING TO A CLUSTER OF THUNDERSTORMS ACROSS ERN NY ATTM...WITH OTHER/MORE ISOLATED STORMS DEVELOPING ACROSS PARTS OF VT/NY/PA SWD INTO NRN VA. DUE TO PERSISTENCE OF STORMS...COLD POOL APPEARS TO BE DEVELOPING WITH THE STORM CLUSTER OVER E CENTRAL/NERN NY NEAR AND W OF GFL /GLEN FALLS NY/...WHICH IS RESULTING IN SOME MESOSCALE ORGANIZATION. THREAT FOR LOCALLY-DAMAGING WINDS AND HAIL WILL CONTINUE ACROSS THIS AREA...PARTICULARLY WITH THE MORE ORGANIZED CLUSTER OF STORMS. ...UPPER MIDWEST... WEAK VORT MAX WILL CONTINUE DRIFTING NWD ACROSS SRN WI...WHILE THUNDERSTORMS PERSIST INVOF THIS FEATURE. THOUGH DEEP-LAYER WIND FIELD REMAINS WEAK...MODERATE INSTABILITY WILL CONTRIBUTE TO A LIMITED HAIL/WIND THREAT WITH STRONGER STORMS INVOF VORT MAX. THREAT SHOULD DIMINISH THIS EVENING AS AIRMASS STABILIZES. ..GOSS.. 05/30/2006