From swody1 at goshenarc.org Sat Jul 1 05:38:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 01:38:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 010537 SWODY1 SPC AC 010535 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1235 AM CDT SAT JUL 01 2006 VALID 011200Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES ACROSS THE CNTRL PLAINS TO THE FRONT RANGE... ...SYNOPSIS... DEEP LAYER FRONT ASSOCIATED WITH UPPER MS VALLEY TO GREAT LAKES SHORT WAVE IMPULSE WILL SETTLE INTO ZONE OF LARGE SCALE CONFLUENCE BETWEEN SUBTROPICAL RIDGE AXIS ESTABLISHED ACROSS THE SRN STATES...AND FASTER ZONAL FLOW REGIME EVOLVING ACROSS THE NRN BORDER STATES. WHILE DYNAMIC FORCING AND DEEPER ASCENT ACCOMPANYING THE LOW AMPLITUDE SHORT WAVE TROUGH WILL SPREAD RAPIDLY EAST FROM THE GREAT LAKES TO NEW ENGLAND THIS PERIOD...LIFT ALONG THE TRAILING/WRN EXTENSION OF THE FRONT...FROM THE MS VALLEY WWD TO THE FRONT RANGE...WILL BE MAINTAINED AND DIURNALLY ENHANCED BY LOW LEVEL CONFLUENCE...WARM AIR ADVECTION...AND OROGRAPHIC FORCING. AN AMALGAMATION OF WEAK SUBTROPICAL DISTURBANCES AND WEAK PERTURBATIONS CAST OFF FROM THE WESTERLIES WILL DRIFT ACROSS THE SRN STATES FROM FL AND THE GULF ACROSS TX TO THE SOUTHWEST AND FOUR CORNERS AND AID SCATTERED TSTM DEVELOPMENT ACROSS THESE AREAS. ...UPPER MS VALLEY/GREAT LAKES... FRONTAL ZONE WILL DEVELOP EWD/SEWD INTO INCREASINGLY UNSTABLE AIR MASS FROM WI/UPPER MI TO LOWER MI AND SWRN ONTARIO. GREATER LOW LEVEL MOISTURE ADVECTING ENEWD FROM THE CORN BELT COUPLED WITH DIURNAL HEATING WILL CONTRIBUTE TO THE DEVELOPMENT OF MODEST INSTABILITY /MLCAPE 1000-1500 J/KG/ AS THE SHORT WAVE TROUGH AND FRONT APPROACH DURING THE AFTERNOON. LOW THROUGH MID LEVEL FLOW WILL INCREASE THROUGH THE DAY AND LEAD TO MORE THAN SUFFICIENT SHEAR FOR ORGANIZED STORMS. LINEAR FORCING WITH THE FRONT SUGGESTS POTENTIAL WILL EXIST FOR LINE SEGMENT/BOW ECHO FORMATION WITH THE WIND DAMAGE THREAT INCREASING FROM WI ACROSS LOWER MI THROUGH THE AFTERNOON AND INTO THE EVENING. SUPERCELL TORNADO AND LARGE HAIL POTENTIAL CANNOT BE RULED OUT WITH FORECAST SOUNDINGS DEPICTING INCREASINGLY STRONG LOW LEVEL FLOW AND EFFECTIVE SRH VALUES IN EXCESS OF 200 M2/S2 ACROSS WEAKLY CAPPED WARM SECTOR. LAKE BREEZE BOUNDARY/CELL INTERACTIONS MAY ALSO LOCALLY ENHANCE THE CHANCE FOR BRIEF TORNADOES. ...CNTRL PLAINS TO FRONT RANGE... SURFACE TEMPERATURES WILL AGAIN CLIMB INTO THE 90S F OVER THE PLAINS AND LEAD TO THE DEVELOPMENT OF NEARLY DRY ADIABATIC LAPSE RATES FROM THE SURFACE THROUGH AT LEAST 3KM AGL. THIS HEATING WILL OCCUR COINCIDENT WITH AN AXIS OF GREATER MOISTURE BENEATH A STRONG CAP AND FOCUSED WITHIN THE CONFLUENT/FRONTAL ZONE WHERE MLCAPE MAY LOCALLY INCREASE TO OVER 2000 J/KG. COMBINATION OF DEEP MIXING AND WEAK HEIGHT FALLS ARE FORECAST TO OVERCOME INHIBITION AND RESULT IN SCATTERED VIGOROUS LATE DAY THROUGH EVENING TSTM DEVELOPMENT. OUTFLOW DOMINANT STORMS WITH DAMAGING WINDS AND SOME HAIL ARE EXPECTED. ALTHOUGH...FARTHER WEST...MOIST POST-FRONTAL UPSLOPE FLOW AND SOMEWHAT GREATER LOW LEVEL DIRECTIONAL SHEAR COULD SUPPORT A FEW HIGH-BASED STORMS WITH SUPERCELLULAR CHARACTERISTICS FROM WRN NEB TO THE FRONT RANGE. ...COASTAL CAROLINAS... STRONG HEATING OF VERY MOIST/WEAKLY CAPPED AIR MASS MAY AGAIN LEAD TO THE DEVELOPMENT OF STRONG TO ISOLATED SEVERE STORMS NEAR THE SEA BREEZE. SIMILAR TO FRIDAY...HAIL COULD OCCUR WITH A FEW OF THE STRONGER UPDRAFTS. WET MICROBURSTS ALSO APPEAR POSSIBLE BASED ON STEEP THETAE LAPSE RATES AND FORECAST DCAPE VALUES OVER 1000 J/KG. ...AZ... THERMODYNAMIC ENVIRONMENT HAS CHANGED LITTLE FROM PAST FEW DAYS AND SHOULD AGAIN SUPPORT THE DEVELOPMENT OF STORMS ACROSS THE HIGHER TERRAIN DURING THE AFTERNOON. DEEP LAYER ELY FLOW ON THE SRN PERIPHERY OF SUBTROPICAL RIDGE WILL AGAIN STEER CONVECTIVE OUTFLOW WWD/SWWD INTO THE LOWER DESERTS WITH ATTENDANT ISOLATED WIND DAMAGE THREAT. ...TX... COOL POCKET ALOFT ASSOCIATED WITH ORPHANED AND NEARLY STATIONARY MID LEVEL VORTEX WILL AGAIN CONTRIBUTE TO THE DEVELOPMENT OF SCATTERED TO NUMEROUS AFTERNOON STORMS ACROSS PARTS OF SCNTRL TX AND THE RIO GRANDE VALLEY. DESPITE WEAK FLOW/SHEAR...MODEST INSTABILITY AND POTENTIAL FOR WELL-MIXED BOUNDARY LAYER COULD RESULT IN A FEW STRONG TO ISOLATED DAMAGING WIND GUSTS. SURGE OF TROPICAL MOISTURE...POSSIBLY ASSOCIATED WITH AN ELY WAVE...IS FORECAST TO SPREAD INLAND ACROSS THE TX GULF COAST AND COULD LEAD TO AN INCREASED THREAT OF ISOLATED WET DOWNBURSTS...OR A BRIEF TORNADO/WATERSPOUT. ...ORE.. UPSLOPE FLOW AND WEAK HEIGHT FALLS MAY AGAIN PROMOTE THE DEVELOPMENT OF A FEW POTENT STORMS WITH SMALL HAIL ACROSS CASCADES DURING THE AFTERNOON. THIS ACTIVITY SHOULD DRIFT EAST ACROSS RELATIVELY DEEP/DRY SUB CLOUD LAYER WITH A SMALL CHANCE OF DAMAGING WINDS. ..CARBIN/GUYER.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 13:00:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 09:00:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011256 SWODY1 SPC AC 011255 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0755 AM CDT SAT JUL 01 2006 VALID 011300Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM THE CENTRAL HIGH PLAINS TO THE UPPER GREAT LAKES AREA.... ...WI/MI AREA THIS AFTERNOON/EVENING... A LOW AMPLITUDE SHORTWAVE TROUGH OVER ERN ND/NW MN THIS MORNING WILL MOVE ESEWD OVER THE UPPER GREAT LAKES REGION LATER THIS AFTERNOON INTO EARLY TONIGHT. A SURFACE LOW WILL MOVE ACROSS SRN ONTARIO IN ADVANCE OF THIS MID LEVEL WAVE...WHILE A TRAILING COLD FRONT ADVANCES SEWD ACROSS IA/WI/MI THIS AFTERNOON. SEVERAL DAYS OF EVAPOTRANSPIRATION HAVE RAISED SURFACE LAYER DEWPOINTS INTO THE MID-UPPER 60S ACROSS THE CORN BELT...IN THE CORRIDOR ALONG A REMNANT NW-SE BAROCLINIC ZONE WHERE THE BOUNDARY LAYER HAS BEEN SHELTERED FROM DEEPER MIXING. THIS MOIST LAYER IS STILL RELATIVELY SHALLOW...BUT SHOULD PERSIST TODAY ACROSS IA/WI AND SPREAD NEWD INTO LOWER MI FROM IL/INDIANA BY AFTERNOON. ADDITIONALLY...A PLUME OF RELATIVELY STEEP MID LEVEL LAPSE RATES WILL OVERSPREAD THE WI/MI AREA IN ADVANCE OF THE MID LEVEL TROUGH. THE STEEP LAPSE RATES...LOW-LEVEL MOISTURE...AND AFTERNOON TEMPERATURES IN THE MID-UPPER 80S WILL ALL CONTRIBUTE TO THE DEVELOPMENT OF MLCAPE VALUES OF 1500-2500 J/KG AHEAD OF THE COLD FRONT BY AFTERNOON. SCATTERED THUNDERSTORMS SHOULD DEVELOP INVOF THE FRONT ACROSS NRN WI/WRN UPPER MI BY MID AFTERNOON...WITH ADDITIONAL STORM DEVELOPMENT EXPECTED FARTHER SW INTO WI AND NE IA BY EVENING. FORECAST VERTICAL SHEAR APPEARS SUFFICIENT FOR A FEW SUPERCELLS IN A BROKEN BAND NEAR THE FRONT...THOUGH SOME OF THE CONVECTION MAY ALSO EVOLVE INTO BOWING LINE SEGMENTS. DAMAGING WINDS AND LARGE HAIL WILL THE MAIN SEVERE THREATS. THE TORNADO THREAT IS MORE UNCERTAIN AND WILL DEPEND ON LOCAL ENHANCEMENTS TO LOW-LEVEL MOISTURE IN THE REGION OF STRONGER LOW-LEVEL SHEAR FROM ERN WI INTO LOWER MI LATER THIS AFTERNOON/EVENING. ...CENTRAL PLAINS/HIGH PLAINS THIS AFTERNOON INTO TONIGHT... A SURFACE COLD FRONT IS MOVING SEWD ACROSS NEB AND NE CO AS OF 12Z...THOUGH THE BOUNDARY SHOULD STALL THIS AFTERNOON FROM ERN CO ACROSS NW KS TO SE NEB AND SRN IA. STRONG SURFACE HEATING WILL OCCUR S OF THE BOUNDARY...WHILE SOMEWHAT RICHER MOISTURE AND MODERATE INSTABILITY WILL BE MAINTAINED IN A NARROW BAND IMMEDIATELY N OF THE FRONT. A FEW THUNDERSTORMS SHOULD DEVELOP ALONG THE BOUNDARY BY LATE AFTERNOON AND PERSIST INTO THE EARLY OVERNIGHT HOURS. VERTICAL SHEAR WILL BE MARGINALLY FAVORABLE FOR SUPERCELLS N OF THE BOUNDARY AND IN THE UPSLOPE FLOW AREA OF NE CO/SE WY...WHICH MAY TEND TO LOCALLY ENHANCE THE THREAT FOR LARGE HAIL. OTHERWISE...STORMS SHOULD EVOLVE INTO A FEW SMALL CLUSTERS WITH THE POTENTIAL TO PRODUCE ISOLATED LARGE HAIL AND DAMAGING WINDS INTO TONIGHT. ...SE ATLANTIC STATES THIS AFTERNOON... ONE WEAK MID LEVEL WAVE IS MOVING OFFSHORE OF NC...WHILE OTHER SUBTLE WAVES ARE LOCATED UPSTREAM OVER TN/KY. 12Z SOUNDINGS SHOW THE POTENTIAL FOR MODERATE INSTABILITY THIS AFTERNOON ACROSS THE CAROLINA COASTAL PLAINS WHERE LOW-LEVEL MOISTURE WILL BE MAXIMIZED. MORNING SOUNDINGS ALSO REVEAL STEEP LAPSE RATES BELOW 700 MB OVER THE SRN APPALACHIANS/TN VALLEY. STRONG SURFACE HEATING WILL RESULT IN PROFILES THAT MAY SUPPORT ISOLATED STRONG DOWNBURSTS OVER PORTIONS OF THE SRN APPALACHIANS AND COASTAL CAROLINAS...AS WELL AS ISOLATED HAIL. ..THOMPSON/GUYER.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 16:30:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 12:30:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011629 SWODY1 SPC AC 011628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT SAT JUL 01 2006 VALID 011630Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM THE GREAT LAKES INTO THE CENTRAL HIGH PLAINS.... ...SYNOPSIS... MID/UPPER LEVEL SHORTWAVE TROUGH/ASSOCIATED VORTICITY MAX IS LOCATED OVER WRN PORTIONS OF LK SUPERIOR THIS MORNING EXTENDING SSWWD THRU CENTRAL IA. THIS FEATURE IS EXPECTED TO TRACK EWD THIS AFTN OVER THE NRN PARTS OF THE GREAT LAKES REGION BEFORE SWINGING NEWD OVER SERN ONTARIO TNGT. BROAD RIDGING WILL CONTINUE ACROSS THE SRN TIER OF THE U.S. WITH THE MAIN BAND OF WESTERLIES REMAINING FROM THE NRN PLATEAU REGION ESEWD THRU THE LOWER GREAT LAKES AND SRN NEW ENGLAND. AT THE SFC...COLD FRONT EXTENDS FROM A LOW JUST NW OF THE NWRN SHORES OF LK SUPERIOR SWWD ACROSS NWRN WI AND NWRN IA INTO SWRN NEB. THIS FRONT WILL PROGRESS EWD WITH THE MID/UPPER LEVEL TROUGH AND PLAY AS THE MAIN SOURCE OF FORCING FOR ACTIVITY THIS AFTN AND TNGT. ...MUCH OF LOWER MI SWWD INTO SRN WI... COLD FRONT WILL PUSH EWD ACROSS MUCH OF NRN AND CENTRAL LOWER MI THIS AFTN AND TRAIL SWWD ACROSS SRN WI. MORNING RAOB DATA INDICATED MAIN BAND 35-45 KT SWLY LOW LEVEL FLOW EXTENDS FROM NERN KS INTO NERN WI AND IS EXPECTED TO REACH FROM NRN IL INTO NERN LOWER MI BY THIS EVENING. WINDS AT 500 MB ARE EXPECTED TO BE WLY AT 45-55 KT FROM SERN MN INTO NRN LOWER MI AND BE SOMEWHAT DIVERGENT ENHANCING VERTICAL SHEAR AND UVVS ALONG/AHEAD OF THE FRONTAL BOUNDARY BY MID AFTN INTO EARLY TNGT. IN ADDITION...AIR MASS IS ALREADY EXPERIENCING SOME DESTABILIZATION AS SFC DEW POINTS ARE IN THE MID 60S AND CURRENT MESOANALYSIS SHOWS LIFTED INDICES AROUND -6 AND MUCAPES ABV 2000 J/KG. THUS...PRIND ARE THUNDERSTORMS WILL BE MOVING INTO WRN LOWER MI EARLY THIS AFTN AHEAD OF THE ADVANCING FRONTAL BOUNDARY. SOME OF THIS ACTIVITY IS EXPECTED TO BECOME SEVERE WITH THE MAIN THREATS BEING DAMAGING WINDS AND HAIL. ...AREAS FROM IA INTO THE HIGH PLAINS OF CO/WY... QUASI STATIONARY FRONTAL BOUNDARY IS EXPECTED TO EXTEND FROM SWRN WI THRU CENTRAL IA INTO NWRN KS AND SERN CO BY LATER THIS AFTN. NWLY WINDS AT THE SFC ATTM ARE EXPECTED TO BECOME MORE ELY BY TONIGHT WHICH WILL ENHANCE UPSLOPE FLOW TO THE AREA. SEVERAL WEAK SHORTWAVES ARE FORECAST TO COME FROM MONSOONAL EXTENSION OVER THE INTERMOUNTAIN REGION MOVING ESEWD WITHIN THE MAIN BAND OF THE WESTERLIES AIDING IN THE DEVELOPMENT OF WIDELY SCATTERED THUNDERSTORMS OVER THE HIGH PLAINS THEN ENEWD ALONG/JUST N OF THE FRONTAL BOUNDARY THIS EVENING AND EARLY TONIGHT. SOME OF THE ACTIVITY COULD PRODUCE SOME HAIL AND DAMAGING WINDS GIVEN VERY STEEP LAPSE RATES BETWEEN 8 AND 8.5C/KM. ..MCCARTHY/TAYLOR.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 19:56:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 15:56:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011955 SWODY1 SPC AC 011953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT SAT JUL 01 2006 VALID 012000Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE HIGH PLAINS...CNTRL PLAINS...UPPER MIDWEST AND GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE FAR NERN STATES... ...UPPER MIDWEST/GREAT LAKES... A WELL-DEFINED SHORTWAVE TROUGH IS EVIDENT ON WATER VAPOR IMAGERY OVER WI AND LAKE SUPERIOR. A LINE OF THUNDERSTORMS IS DEVELOPING JUST AHEAD OF THE PRIMARY VORTICITY MAX ALONG A COLD FRONT OVER NRN WI AND UPPER MI. THUNDERSTORMS SHOULD CONTINUE TO INCREASE IN COVERAGE MOVING SEWD ACROSS ERN WI...UPPER MI AND INTO NRN LOWER MI LATE THIS AFTERNOON. OBJECTIVE ANALYSIS CURRENTLY SHOWS A MAXIMUM OF STRONG INSTABILITY OVER WCNTRL WI WHERE MLCAPE VALUES RANGE FROM 2500 TO 3000 J/KG. INSTABILITY IS INCREASING ACROSS LOWER MI WHERE MLCAPE VALUES RANGE FROM 1000 TO 1500 J/KG. IN ADDITION...FORECAST SOUNDINGS SHOW STRONG VERTICAL SHEAR PROFILES IN PLACE ASSOCIATED WITH A 60 KT MID-LEVEL JET CENTERED OVER NERN WI. THE STRONG SHEAR AND INSTABILITY SUGGEST SUPERCELLS AND/BOW ECHOES WILL BE LIKELY. A PLUME OF STEEP MID-LAPSE RATES EXIST FROM IA EXTENDING ENEWD INTO LOWER MI SUGGESTING LARGE HAIL WILL BE LIKELY WITH SUPERCELLS. THE STRONG LOW-LEVEL SHEAR MAY BE FAVORABLE FOR A TORNADO OR TWO WITH SUPERCELLS THAT PERSIST INTO THE LATE AFTERNOON. WIND DAMAGE WILL ALSO BE LIKELY WITH BOW ECHOES EMBEDDED IN THE LINE DUE TO THE STEEP LOW-LEVEL LAPSE RATES AND STRONG LOW-LEVEL FLOW IN PLACE. AN ISOLATED SEVERE THREAT SHOULD CONTINUE INTO THE EVENING AS A LARGE MCS ORGANIZES AND TRACKS SEWD ACROSS SRN WI...LAKE MI AND THE LOWER PENINSULA OF MI. ...FAR NERN STATES... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER LOW OVER ERN QUEBEC WITH STRONG WLY FLOW IN PLACE ACROSS NEW ENGLAND. LARGE-SCALE ASCENT AND COLD AIR ALOFT ASSOCIATED WITH THE TROUGH IS RESULTING IN SCATTERED THUNDERSTORM DEVELOPMENT IN THE NRN APPALACHIAN MTNS AND IN THE COASTAL PLAINS OF NEW ENGLAND. ALTHOUGH INSTABILITY IS RELATIVELY WEAK...LAPSE RATES ARE VERY STEEP AS SHOWN BY OBJECTIVE ANALYSIS. THIS COMBINED WITH THE STRONGER VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS SUGGEST A SEVERE THREAT WILL LIKELY CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON. LARGE HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE WITH THE STRONGER MULTICELL STORMS. ...HIGH PLAINS/CNTRL PLAINS... WATER VAPOR IMAGERY CURRENTLY SHOWS A PLUME OF MONSOONAL MOISTURE IN PLACE ACROSS THE FOUR CORNERS REGION EXTENDING NEWD INTO THE HIGH PLAINS. SCATTERED STRONG THUNDERSTORMS HAVE DEVELOPED FROM ERN MT SWD ACROSS ERN WY INTO NRN CO. OBJECTIVE ANALYSIS SHOWS POCKETS OF MODERATE INSTABILITY IN PLACE ACROSS THE HIGH PLAINS EXTENDING EWD INTO SRN NEB ALONG A FRONTAL BOUNDARY WHERE ADDITIONAL STORMS MAY INITIATE LATE THIS AFTERNOON. UPSLOPE FLOW IS IN PLACE ACROSS MOST OF THE REGION WHICH IS CREATING STRONG DIRECTIONAL SHEAR PROFILES IN THE LOWER TO MID-LEVELS. AS A RESULT...THE STORMS WILL HAVE ACCESS TO MODERATE VERTICAL SHEAR SUGGESTING A SUPERCELL THREAT WILL CONTINUE THIS AFTERNOON THROUGH EARLY EVENING. STEEP MID-LEVEL LAPSE RATES WILL FAVOR LARGE HAIL AS THE MAIN THREAT ALTHOUGH AN ISOLATED WIND DAMAGE THREAT MAY ALSO ACCOMPANY THE STRONGER CELLS. ..BROYLES.. 07/01/2006  From swody1 at goshenarc.org Sun Jul 2 01:08:35 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 21:08:35 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020107 SWODY1 SPC AC 020106 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT SAT JUL 01 2006 VALID 020100Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES SWWD TO THE CNTRL PLAINS... ...UPPER MS VALLEY/GREAT LAKES... VIGOROUS SHORT WAVE IMPULSE WAS DEPICTED WELL BY LATEST WATER VAPOR SATELLITE LOOP AND WAS TRACKING EAST ACROSS THE NWRN GREAT LAKES REGION. ASSOCIATED FRONTAL BAND/WIND SHIFT WAS SITUATED FROM NRN LOWER MI WSWWD ACROSS WI/IA...AND THEN FROM SERN NEB TO NWRN KS. DESPITE SOMEWHAT LIMITED INSTABILITY DOWNWIND FROM LAKE MI...ACROSS MUCH OF LOWER MI...STRONG DYNAMIC FORCING ASSOCIATED WITH THE MID LEVEL IMPULSE AND FRONTAL LIFT SHOULD CONTINUE TO SUPPORT AT LEAST A COUPLE OF SEVERE STORMS WITH WIND AND HAIL AS THE FRONT CROSSES THE REGION TONIGHT. BOTH CAP AND INSTABILITY STRENGTHEN SWWD ALONG THE FRONT/WIND SHIFT...FROM WI/IA SWWD ACROSS NEB/KS. DIURNAL HEATING COUPLED WITH LIFT ALONG THE FRONT HAVE EFFECTIVELY OVERCOME INHIBITION AND RESULTED IN INTENSE STORM DEVELOPMENT FROM NERN IA INTO SRN WI OVER THE PAST FEW HOURS. RUC SOUNDINGS AND DIAGNOSTIC DATA INDICATE THAT STRONG DIRECTIONAL AND SPEED SHEAR IN THE STORM UPDRAFT LAYER WERE CONTRIBUTING TO HIGH VALUES OF LOW LEVEL SR-HELICITY...AND EFFECTIVE CLOUD-BEARING SHEAR WAS MORE THAT SUFFICIENT FOR SUPERCELLS. THE PRESENCE OF MODEST AMBIENT INHIBITION AND WARM/DRY AIR ABOVE THE SURFACE LAYER ARE PROBABLY RESULTING IN A RELATIVELY HIGH LFC WHICH MAY TEND TO LESSEN A MORE SIGNIFICANT TORNADO THREAT. HOWEVER... ACTIVITY WILL REMAIN CAPABLE OF LARGE HAIL AND DAMAGING WINDS AS IT SPREADS ESEWD FROM THE MS RIVER ACROSS SRN WI AND NRN IL AND SWRN MI THROUGH LATE TONIGHT. ...CNTRL PLAINS... MOIST POST-FRONTAL UPSLOPE FLOW HAS AIDED DEEP CONVECTION DEVELOPING EAST ACROSS ERN CO...NWRN NEB...AND EXTREME SWRN SD. IN ADDITION... MORE ISOLATED POST-FRONTAL ACTIVITY HAS INITIATED FROM NWRN KS ACROSS ERN NEB WHERE MOISTENING AND FRONTAL LIFT HAVE ACTED TO OVERCOME STRONG INHIBITION. WHILE THERE APPEARS TO BE SUFFICIENT INSTABILITY AND POCKETS OF GREATER DEEP LAYER SHEAR TO MAINTAIN A CHANCE FOR SEVERE STORMS ACROSS THESE AREAS...GENERALLY WEAKER LARGE SCALE UPWARD MOTION MAY LIMIT COVERAGE AND PERSISTENCE THROUGH LATER TONIGHT. INCREASING NOCTURNAL LOW LEVEL JET FROM KS TO NEB WILL BE DIRECTED INTO THE DEEP LAYER FRONTAL ZONE AND MAY PROVE ADEQUATE TO MAINTAIN A CHANCE FOR SCATTERED SEVERE STORMS OVER THE CNTRL PLAINS FOR AT LEAST SEVERAL MORE HOURS. ..CARBIN.. 07/02/2006  From swody1 at goshenarc.org Sun Jul 2 05:58:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 01:58:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020558 SWODY1 SPC AC 020556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT SUN JUL 02 2006 VALID 021200Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL/NRN PLAINS...ACROSS THE MIDWEST/UPPER OH VALLEY...TO THE NORTHEAST... ...SYNOPSIS... GENERALLY WEAK HEIGHT FALLS WILL ACCOMPANY A PAIR OF LOW AMPLITUDE SHORT WAVE TROUGHS EMBEDDED WITHIN A LARGER SCALE BAND OF MODEST WNWLY FLOW FROM SCNTRL CANADA TO THE NORTHEAST THIS PERIOD. THE LEAD DISTURBANCE...CURRENTLY CROSSING THE GREAT LAKES...WILL CONTINUE EAST TO QUEBEC BEFORE MOVING ACROSS THE ST. LAWRENCE VALLEY TO NRN NEW ENGLAND THROUGH SUNDAY NIGHT. THE FRONTAL ZONE ASSOCIATED WITH THIS FEATURE...EMBEDDED WITHIN A RELATIVELY STRONG DEEP-LAYER FLOW FIELD...WILL SPREAD ESEWD ACROSS THE NORTHEAST THROUGH TONIGHT. THE WRN EXTENSION OF THIS FRONT WILL REMAIN QUASI-STATIONARY FROM THE UPPER OH VALLEY/MIDWEST TO THE CNTRL PLAINS. WEAK MID/UPPER LEVEL PERTURBATIONS...EMANATING IN PART FROM WIDESPREAD DEEP CONVECTION ACROSS THE ROCKIES...IN COMBINATION WITH PERSISTENT MASS INFLOW ON THE NOSE OF GREAT PLAINS LOW LEVEL JET...WILL MAINTAIN THE PROSPECTS FOR ASCENT ALONG THIS PORTION OF THE STALLED BOUNDARY. THE NEXT UPSTREAM IMPULSE IN THE FASTER NWLY FLOW ACROSS SRN CANADA AND THE NRN U.S. WILL BRING A WEAK COLD FRONT ACROSS THE NRN PLAINS AND UPPER MS VALLEY THROUGH EARLY MONDAY. ...NORTHEAST... CONVECTION IS FORECAST TO CONTINUE SPREADING EAST FROM THE GREAT LAKES AND UPSTATE NY INTO NRN NEW ENGLAND EARLY TODAY AIDED BY LIFT AND WEAK DESTABILIZATION ON THE NOSE OF WLY LOW LEVEL JET. IN THE WAKE OF THIS EARLY WARM CONVEYOR BELT CONVECTION...WEAK TO MODERATE INSTABILITY /MLCAPE 500-1500 J PER KG/ SHOULD DEVELOP IN AN AXIS FROM SRN NY/NRN PA ENEWD ACROSS SRN/CNTRL NEW ENGLAND. SCATTERED CONVECTION OCCURRING ALONG THE WEAK COLD FRONT/WIND SHIFT SHOULD INCREASE IN BOTH COVERAGE AND INTENSITY AS GREATER INSTABILITY IS REALIZED AND FRONTAL FORCING SPREADS ESEWD. RELATIVELY STRONG WLY FLOW THROUGH THE TROPOSPHERE AND POTENTIALLY STEEP LOW LEVEL LAPSE RATES SUGGEST FAST MOVING BANDS/CLUSTERS OF STORMS WITH A TENDENCY TO BOW OUT AND PRODUCE WIND DAMAGE. STRONG LOW LEVEL SHEAR...THE POSSIBILITY OF RESIDUAL OUTFLOW/DIFFERENTIAL HEATING BOUNDARIES...AND LOCALLY LOWER LFC...MAY ENHANCE THE THREAT FOR A FEW SUPERCELLS WITH LARGE HAIL AND PERHAPS A TORNADO FOR ANY CELLS REMAINING DISCRETE. GREATEST SEVERE POTENTIAL APPEARS TO EVOLVE FROM PA TO NRN NJ/SERN NY...AND ACROSS SWRN NEW ENGLAND THROUGH LATE AFTERNOON WHERE GREATEST CHANCE FOR STRONG DESTABILIZATION WILL OCCUR AHEAD OF STRENGTHENING MID LEVEL FLOW. ...OH VALLEY/MIDWEST TO CNTRL HIGH PLAINS... MODERATE INSTABILITY /MLCAPES OF 1500-2500 J PER KG/ WILL DEVELOP ALONG THE QUASI-STATIONARY FRONT FROM OH WWD TO THE CNTRL PLAINS GIVEN STEEP LAPSE RATES/STRONG HEATING AND RELATIVELY MOIST LOW LEVEL AIR MASS. PERSISTENT LOW-LEVEL CONVERGENCE...COUPLED WITH THE INFLUENCE OF WEAK IMPULSES EMBEDDED WITHIN MID-LEVEL FLOW...WILL AID IN THE DEVELOPMENT OF SCATTERED AFTERNOON AND EVENING STORMS. WHILE STRONGER WLY FLOW WILL RESIDE A BIT NORTH OF THE GREATEST INSTABILITY...SUFFICIENT EFFECTIVE SHEAR WILL EXIST FOR ORGANIZED SEVERE STORMS...INCLUDING A FEW SUPERCELLS AND BOWING STRUCTURES. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER HAZARDS. MOIST UPSLOPE FLOW INTO HIGHER HEATED TERRAIN WILL OVERCOME INHIBITION AND LEAD TO STORM DEVELOPMENT ACROSS CO/WY. THIS ACTIVITY...SIMILAR TO SATURDAY...WILL MOVE SLOWLY EAST INTO MOIST POST-FRONTAL AIR MASS WHERE SHEAR AND INSTABILITY WILL MARGINALLY SUPPORT SOME HAIL AND WIND POTENTIAL. ONE OR TWO OF THESE CLUSTERS OF STORMS MAY PERSIST WELL INTO THE NIGHT AS NOCTURNAL LOW LEVEL JET INTENSIFIES AND MAINTAINS MASS INFLOW/LIFT ACROSS THE FRONTAL ZONE. ...NRN PLAINS... LOW LEVEL WARM AIR ADVECTION IS EXPECTED TO INTENSIFY LATE IN THE PERIOD AHEAD OF SHORT WAVE TROUGH DEVELOPING SEWD FROM SCNTRL CANADA. STEEP LAPSE RATES...INCREASING ASCENT AND MOISTENING... FROM THE DAKOTAS TO MN...MAY SUPPORT THE DEVELOPMENT OF A LATE-NIGHT MCS ACROSS THESE AREAS THROUGH EARLY MONDAY. A FEW HAIL EVENTS APPEAR POSSIBLE WITH THIS SCENARIO. ..CARBIN/GUYER.. 07/02/2006  From swody1 at goshenarc.org Sun Jul 2 12:56:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 08:56:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 021255 SWODY1 SPC AC 021253 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 AM CDT SUN JUL 02 2006 VALID 021300Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY FROM THE UPPER OH VALLEY INTO NEW ENGLAND...AND INTO TONIGHT FROM THE CENTRAL HIGH PLAINS TO PORTIONS MN/IA.... ...UPPER OH VALLEY TO NEW ENGLAND TODAY... A MID LEVEL SHORTWAVE TROUGH OVER SW QUEBEC WILL MOVE EWD OVER NEW ENGLAND TODAY...WHILE ANOTHER UPSTREAM WAVE OVER SRN ONTARIO FOLLOWS A SIMILAR TRAJECTORY IN THE BROAD CYCLONIC FLOW REGIME FROM NRN MN TO MAINE. A SURFACE CYCLONE WILL ACCOMPANY THE MID LEVEL WAVE ACROSS NRN MAINE...WHILE A WEAK SURFACE TROUGH TRAILS SWWD ACROSS NY/PA INTO THE NRN OH VALLEY STATES. ONGOING ELEVATED STORMS OVER NY/VT/NH WILL SPREAD EWD TODAY. SOME OF THIS CONVECTION MAY INTENSIFY ACROSS PA/NY/SRN NEW ENGLAND BY MIDDAY AS THE LOW LEVELS DESTABILIZE...WHILE THE PRIMARY THREAT FOR SEVERE STORMS ACROSS MAINE WILL BE IN THE WAKE OF THIS EARLY CONVECTION. MODEST WARM SECTOR INSTABILITY IS EXPECTED TODAY WITH SURFACE DEWPOINTS IN THE LOW-MID 60S AND TEMPERATURES GENERALLY IN THE 80S...WHILE VERTICAL SHEAR WILL BE STRONGER ACROSS NRN NEW ENGLAND IN ASSOCIATION WITH THE MAIN BELT OF MID LEVEL WESTERLIES. BOTH BOWING SEGMENTS AND SUPERCELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS...MARGINALLY SEVERE HAIL...AND PERHAPS A TORNADO. ...CENTRAL HIGH PLAINS TO MS VALLEY THIS AFTERNOON/TONIGHT... A DIFFUSE FRONTAL ZONE EXTENDS FROM ERN CO/NW KS TO SRN IA AND NRN IL/SRN LOWER MI. THIS BOUNDARY HAS BEEN REINFORCED SOME BY OVERNIGHT RAINFALL...AND DIFFERENTIAL HEATING MAY HELP MAINTAIN ITS IDENTITY ALONG THE SRN FRINGE OF THE MID LEVEL WESTERLIES. MODERATE INSTABILITY AGAIN CAN BE EXPECTED ALONG THE IMMEDIATE B0UNDARY WHERE SURFACE HEATING AND A BELT OF MID 60 DEWPOINTS CONTRIBUTE TO MLCAPE VALUES NEAR 1500 J/KG. MEANWHILE...VERTICAL SHEAR SHOULD BE MARGINAL FOR SUPERCELLS...WITH MULTICELL CLUSTERS THE MORE PROBABLE STORM MODE. ISOLATED LARGE HAIL AND DAMAGING OUTFLOW GUSTS WILL BE POSSIBLE WITH THE STRONGEST STORMS THIS AFTERNOON. THE SURFACE BOUNDARY SHOULD BEGIN TO LIFT NWD TONIGHT AS A SWLY LLJ DEVELOPS FROM THE CENTRAL PLAINS TO THE MID/UPPER MS VALLEY... IN RESPONSE TO ANOTHER MID LEVEL TROUGH DIGGING SEWD TOWARD WRN ONTARIO AND THE MN ARROWHEAD AREA. WAA ON THE NOSE OF THE LLJ AND ASCENT ALONG A DEVELOPING SURFACE COLD FRONT SHOULD SUPPORT ELEVATED THUNDERSTORMS TONIGHT AS THE LOW LEVELS GRADUALLY MOISTEN/DESTABILIZE. LARGE HAIL WILL BE THE MAIN SEVERE THREAT...THOUGH ISOLATED DAMAGING WINDS MAY ALSO OCCUR SINCE THE SURFACE-BASED INVERSION LAYER SHOULD BE FAIRLY SHALLOW OVERNIGHT. ...INTERIOR ORE LATE THIS AFTERNOON... A WEAK MID LEVEL TROUGH /APPARENT IN WATER VAPOR IMAGERY NEAR 40 N AND 127 W/ WILL MOVE NEWD OVER EXTREME NW CA AND ORE BY LATE TODAY. THIS APPROACHING WAVE WILL PROVIDE WEAK LARGE SCALE ASCENT OVER ORE...WHILE STRONG SURFACE HEATING AND OBSERVED BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 40S F CONTRIBUTE TO LATE AFTERNOON MLCAPE VALUES OF 500-1000 J/KG. EXPECT A FEW THUNDERSTORMS TO DEVELOP NEAR AND E OF THE CASCADES THIS AFTERNOON AND PERSIST INTO EARLY TONIGHT WITH THE POTENTIAL FOR MARGINALLY SEVERE HAIL/WINDS. ..THOMPSON/GUYER.. 07/02/2006  From swody1 at goshenarc.org Mon Jul 3 01:24:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 21:24:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 030101 SWODY1 SPC AC 030059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT SUN JUL 02 2006 VALID 030100Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM IA ESEWD INTO THE OH VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM DELMARVA TO NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL/NRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN ORE AND SRN ID... ...IA ESEWD THROUGH OH VALLEY... EARLY EVENING SURFACE ANALYSIS SHOWED A BOUNDARY EXTENDING FROM NRN OH WWD TO THE IA/MO BORDER TO SERN NEB THEN SWWD INTO NRN TO WRN KS. ERN PART OF THIS FRONT WILL MOVE SLOWLY SWD THROUGH OH AIDED BY A SHORT WAVE TROUGH MOVING EWD THROUGH THE SRN GREAT LAKES REGION. THE PART OF THE BOUNDARY ALONG THE IA/MO BORDER SHOULD LIFT N TOWARD CENTRAL IA OVERNIGHT. ASCENT AHEAD OF THE SRN GREAT LAKES TROUGH IS EXPECTED TO SUPPORT ADDITIONAL STORMS ACROSS CENTRAL IND/CENTRAL-NRN OH INTO WRN PA WHERE THE AIR MASS IS EXPECTED TO REMAIN MODERATELY UNSTABLE THROUGH THIS EVENING. DEEP WLY WIND FIELDS WILL CONTINUE TO SUPPORT LINE SEGMENTS...WITH EFFECTIVE BULK SHEAR VALUES /35-45 KT/ ALSO SUGGESTING A CONTINUED POTENTIAL FOR SUPERCELLS ACROSS PARTS OF NRN IND/NRN OH TO WRN PA. FARTHER W...STRENGTHENING SWLY LLJ IS EXPECTED TO EXTEND NEWD INTO SWRN/CENTRAL IA OVERNIGHT. DESTABILIZATION AND INCREASING CONVERGENCE/LOW LEVEL WAA IN THE VICINITY OF THE SURFACE BOUNDARY AND NOSE OF LLJ SHOULD ALLOW FOR ADDITIONAL STORMS TO DEVELOP NNEWD INTO CENTRAL IA/NRN IL...POTENTIALLY REACHING FAR SERN MN/SRN WI. EFFECTIVE BULK SHEAR AND ELEVATED MODERATE INSTABILITY EXPECTED TO SUPPORT THE POTENTIAL FOR LARGE HAIL. IN ADDITION...POINT FORECAST SOUNDINGS SUGGEST A RATHER SHALLOW SURFACE INVERSION OVERNIGHT RESULTING IN A THREAT FOR STRONG WIND GUSTS TO REACH THE SURFACE. ...DELMARVA TO NEW ENGLAND... SURFACE TROUGH EXTENDED SWD FROM MAINE TO THE DELMARVA REGION... WHILE A COLD FRONT EXTENDED FROM NRN MAINE SWWD TO UPSTATE NY. THESE BOUNDARIES ARE EXPECTED TO CONTINUE TO MOVE EWD OVERNIGHT AND SHOULD BE JUST OFF THE NORTHEAST COAST BY 12Z MONDAY. EFFECTIVE DEEP LAYER SHEAR REMAINS SUFFICIENT FOR ORGANIZED STORMS WITH THE GREATEST SEVERE THREAT FOR THE NEXT FEW HOURS /UNTIL 03 OR 04Z/ ACROSS NRN NEW ENGLAND AND SWD FROM NJ TO THE DELMARVA REGION. ...PARTS OF CENTRAL/NRN HIGH PLAINS... ONGOING CLUSTERS OF STORMS ACROSS NERN CO AND WRN NEB SHOULD GROW UPSCALE INTO ONE OR TWO MCS/S TONIGHT AS A SLY LLJ STRENGTHENS ALONG THE HIGH PLAINS. MODERATE ELEVATED INSTABILITY AND SUFFICIENT EFFECTIVE BULK SHEAR VALUES SHOULD SUPPORT A THREAT FOR HAIL AND STRONG WIND GUSTS WITH THE STRONGEST ACTIVITY. ...ERN ORE/SRN ID... A PAIR OF SHORT WAVE TROUGHS /1. MOVING INTO WRN ORE AND 2. MOVING INTO SRN ID/ PER WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NEWD. ASCENT WITH THESE FEATURES WILL CONTINUE TO SUPPORT ADDITIONAL THUNDERSTORMS THROUGH THE EVENING ACROSS CENTRAL/ERN ORE INTO MUCH OF SRN ID. MODERATE INSTABILITY AND DEEP LAYER SHEAR RANGING FROM 35-40 KT WILL AID IN A THREAT FOR HAIL AND STRONG WIND GUSTS. ...ERN DAKOTAS/MN/NWRN WI/WRN U.P. OF MI... MID LEVEL IMPULSE AND ACCOMPANYING 50-60 KT WLY JET WILL TRACK FROM SRN MANITOBA EWD INTO ONTARIO/UPPER GREAT LAKES OVERNIGHT. ASCENT WITHIN THE ENTRANCE REGION OF THIS JET WILL CONTINUE TO SUPPORT THUNDERSTORM DEVELOPMENT THIS FORECAST PERIOD ALONG A COLD FRONT SPREADING EWD ACROSS THE ERN DAKOTAS/NRN MN. ALTHOUGH DEEP LAYER SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORMS...WEAK INSTABILITY SHOULD LIMIT THE SEVERE THREAT. ..PETERS.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 06:05:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 02:05:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 030604 SWODY1 SPC AC 030603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT MON JUL 03 2006 VALID 031200Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE NRN/CENTRAL HIGH PLAINS EWD TO THE GREAT LAKES/OH VALLEY AND NY... ...SYNOPSIS... MID/UPPER LEVEL CLOSED LOW WILL TRACK ESEWD ACROSS NRN ONTARIO TODAY MAINTAINING BROAD CYCLONIC FLOW REGIME FROM THE NRN PLAINS/UPPER MS VALLEY ACROSS THE GREAT LAKES/OH VALLEY TO THE NERN STATES. PRIMARY SHORT WAVE TROUGH ASSOCIATED WITH THIS UPPER LOW IS PROGGED TO MOVE SEWD FROM THE UPPER MS VALLEY INTO THE GREAT LAKES REGION. SEVERAL WEAK MID LEVEL IMPULSES SHOULD TRAVERSE THE SRN EXTENT OF STRONGER FLOW ALOFT FROM THE CENTRAL PLAINS EWD THROUGH THE LOWER MO TO OH VALLEYS AND OFF THE MID ATLANTIC COAST. MEANWHILE...UPSTREAM SHORT WAVE TROUGH...CURRENTLY LOCATED ACROSS THE NRN INTERMOUNTAIN WEST... IS EXPECTED TO TOP THE RIDGE AXIS OVER WRN MT EARLY TODAY AND THEN TURN ESEWD ACROSS MT REACHING THE WRN DAKOTAS LATE TONIGHT. IN THE LOW LEVELS...SURFACE BOUNDARY EXTENDING FROM OH WWD TO CENTRAL IL THEN GENERALLY WSWWD ACROSS SRN IA TO WRN KS/ERN CO IS EXPECTED TO REMAIN QUASI-STATIONARY THROUGH THE FORECAST PERIOD. MEANWHILE...COLD FRONT ACCOMPANYING UPPER MS VALLEY/GREAT LAKES SHORT WAVE TROUGH SHOULD EXTEND FROM THE MN ARROWHEAD SWWD TO ERN SD AT 12Z TODAY AND THEN EXTEND FROM THE ERN U.P. OF MI ACROSS ERN WI TO SERN IA BY 04/00Z. ...GREAT LAKES/OH VALLEY/PARTS OF UPPER AND MID MS VALLEY... THUNDERSTORMS MAY BE ONGOING AT THE START OF THE PERIOD ESEWD FROM IA INTO PARTS OF THE OH VALLEY. MODELS SUGGEST THIS ACTIVITY SHOULD WEAKEN THIS MORNING. MOIST AIR MASS /SURFACE DEWPOINTS IN THE MID 60S TO AROUND 70/ ALREADY IN PLACE ALONG THE QUASI-STATIONARY BOUNDARY EXTENDING FROM MID MS VALLEY INTO OH VALLEY IS EXPECTED TO BECOME MODERATELY UNSTABLE TODAY. WEAK MID LEVEL IMPULSE PROGGED TO MOVE ACROSS THIS REGION IS EXPECTED TO SUPPORT SCATTERED THUNDERSTORM DEVELOPMENT THROUGH THE AFTERNOON WITH HAIL AND STRONG WIND GUSTS BEING THE PRIMARY THREATS. FARTHER N AND W...STRENGTHENING SWLY LOW LEVEL WINDS AHEAD OF THE COLD FRONT WILL ALLOW MOISTURE TO RETURN NEWD INTO THE UPPER GREAT LAKES REGION WITH SURFACE DEWPOINTS IN THE UPPER 50S TO AROUND 60 REACHING MUCH OF THE UPPER PENINSULA OF MI AND NRN LOWER MI. SURFACE HEATING WITHIN THIS MOIST AIR MASS WILL RESULT IN MODERATE INSTABILITY IN THE WARM SECTOR WITH STRONGEST INSTABILITY EXPECTED ACROSS PARTS OF SRN WI/ERN IA AND NRN IL WHERE SURFACE DEWPOINTS WILL BE GREATEST. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE COLD FRONT BY EARLY AFTERNOON FROM NERN NEB THROUGH SERN MN TO MUCH OF THE WRN UPPER PENINSULA OF MI. ACTIVITY WILL THEN DEVELOP ESEWD ACROSS THE GREAT LAKES REGION AND TOWARD THE LOWER MO AND OH VALLEYS THIS EVENING/OVERNIGHT. MAINLY DEEP WNWLY WIND FIELDS SHOULD RESULT IN BOWING LINE SEGMENTS WITH DAMAGING WINDS THE PRIMARY THREAT. ...CENTRAL/ERN NY AND WRN VT... WEAK MID LEVEL IMPULSE AND ATTENDANT N-S ORIENTED SURFACE TROUGH ARE PROGGED TO MOVE EWD ACROSS THIS REGION TODAY INTO THIS EVENING. RESIDUAL MOISTURE ACROSS THIS REGION IS EXPECTED TO AID IN THE AIR MASS BECOMING MODERATELY UNSTABLE BY AFTERNOON AND SUPPORTING THUNDERSTORM DEVELOPMENT ALONG THE SURFACE TROUGH. THE INSTABILITY COMBINED WITH FAVORABLE DEEP LAYER SHEAR IS EXPECTED TO RESULT IN A SEVERE THREAT INTO THE EARLY EVENING. ...SRN MT SEWD TO NERN CO/NRN KS/NEB... ASCENT AHEAD OF THE NRN INTERMOUNTAIN SHORT WAVE TROUGH IS EXPECTED TO SPREAD ACROSS THE HIGHER TERRAIN OF SWRN MT/WRN WY BY EARLY AFTERNOON SUPPORTING THUNDERSTORM DEVELOPMENT. DESPITE SOMEWHAT DRY LOW LEVELS ACROSS SRN MT/WY...STEEP LAPSE RATES ARE EXPECTED TO SUPPORT MLCAPE VALUES AROUND 1000 J/KG. GREATER MOISTURE INTO THE CENTRAL PLAINS SHOULD RESULT IN A MODERATELY UNSTABLE AIR MASS FARTHER SE ALONG THE WRN EXTENT OF THE SURFACE BOUNDARY FROM ERN CO TO SRN NEB/NRN KS. THUNDERSTORMS ARE EXPECTED TO DEVELOP AND SPREAD ESEWD INTO THE NRN/CENTRAL HIGH PLAINS THIS AFTERNOON/EVENING WITH SUFFICIENT DEEP LAYER SHEAR RESULTING IN HAIL/STRONG WIND GUSTS. INCREASING UPSLOPE FLOW THIS EVENING INTO SERN MT MAY ALLOW STORMS TO PERSIST INTO THE OVERNIGHT PERIOD AS THE SHORT WAVE TROUGH APPROACHES THE WRN DAKOTAS...BUT DECREASING INSTABILITY SHOULD LIMIT THE SEVERE THREAT LATER TONIGHT. FARTHER SE...CONVERGENCE ALONG THE SURFACE BOUNDARY AND/OR UPSLOPE FLOW WILL SUPPORT THUNDERSTORM DEVELOPMENT FROM ERN CO EWD INTO NEB AND WRN/NRN KS. HAIL AND DAMAGING WINDS WILL ALSO BE A THREAT ACROSS THESE STATES. ...CENTRAL/ERN ORE INTO SRN ID/NWRN UT... A SHORT WAVE TROUGH APPROACHING ORE AND A SECOND IMPULSE APPROACHING THE NRN INTERMOUNTAIN REGION THIS AFTERNOON/EVENING SHOULD SUPPORT ISOLATED STRONG TO SEVERE STORMS FROM CENTRAL/ERN ORE INTO SRN ID AND NWRN UT. AIR MASS ACROSS THESE REGIONS IS EXPECTED TO BECOME MARGINALLY TO MODERATELY UNSTABLE WITH INCREASING DEEP LAYER SHEAR SUPPORTING STORM ORGANIZATION FOR A FEW SEVERE STORMS. ..PETERS/GUYER.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 12:52:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 08:52:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031251 SWODY1 SPC AC 031249 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 AM CDT MON JUL 03 2006 VALID 031300Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY INTO TONIGHT FROM WI/IA EWD TO PARTS OF PA/NY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FOR SRN MT AND NRN/ERN WY.... ...UPPER GREAT LAKES AREA THIS AFTERNOON/TONIGHT... PRIMARY SYNOPTIC FEATURE OF INTEREST THIS PERIOD WILL BE A STRONG MID LEVEL TROUGH MOVING ESEWD OVER ONTARIO AND THE UPPER GREAT LAKES. THIS WILL BE ACCOMPANIED BY A SURFACE CYCLONE INVOF JAMES BAY...AND AN ASSOCIATED COLD FRONT WILL MOVE SEWD FROM THE NRN PLAINS TO THE GREAT LAKES AND CENTRAL PLAINS BY EARLY TUESDAY. LOW-LEVEL MOISTENING/DESTABILIZATION IS EXPECTED TODAY ACROSS THE WI AREA IN ADVANCE OF THE COLD FRONT AND IN THE WAKE OF MORNING CONVECTION OVER NRN IL. THE NET RESULT SHOULD BE AFTERNOON MLCAPE VALUES OF 1500-2500 J/KG...BASED ON BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S AND TEMPERATURES OF 85-90 F. DEBRIS CLOUDINESS FROM THE WEAK CONVECTION OVER NW WI MAY SLOW SURFACE HEATING SOME TODAY ACROSS NRN WI AND UPPER MI...AND COULD LIMIT INSTABILITY. ADDITIONAL THUNDERSTORMS SHOULD DEVELOP ALONG THE COLD FRONT BY MID AFTERNOON ACROSS WI...AND POSSIBLE WRN UPPER MI IF CLOUD BREAKS OCCUR. THIS CONVECTION SHOULD THEN SPREAD ESEWD ACROSS LOWER MI AND THE NRN PORTIONS OF IL/INDIANA/OH TONIGHT. THE COMBINATION OF MODERATE INSTABILITY AND 0-6 KM VECTOR SHEAR ORIENTED ACROSS THE SURFACE FRONT MAY SUPPORT A FEW SUPERCELLS DURING THE AFTERNOON ACROSS THE WI AREA. CONVECTION WILL LIKELY EVOLVE INTO CLUSTERS/ LINE SEGMENTS WHILE MOVING SEWD OVERNIGHT...WITH A CONTINUED THREAT FOR DAMAGING GUSTS AND LARGE HAIL. ...OH VALLEY INTO PA/NY TODAY... SEVERAL SMALL SCALE WAVES ARE EMBEDDED IN THE SRN FRINGE OF THE WLYS...WITH THE MORE PRONOUNCED WAVES NOW MOVING EWD OVER ERN IA AND CENTRAL/ERN PA. AT THE SURFACE...A DIFFUSE BAROCLINIC ZONE EXTENDS FROM IA ACROSS LOWER MI TO NY...WITH A SECONDARY BOUNDARY RELATED TO OVERNIGHT/ONGOING CONVECTION FROM NRN IL TO SRN OH AND THE NRN CHESAPEAKE REGION. A FEW MULTICELL CLUSTERS MAY PERSIST DURING THE DAY ALONG THE SRN BOUNDARY...SUSTAINED BY SURFACE HEATING/DESTABILIZATION. OTHER STORMS MAY ALSO FORM BY MIDDAY/EARLY AFTERNOON ACROSS CENTRAL NY ALONG THE BAROCLINIC ZONE. DEEP LAYER WNWLY SHEAR AND MODEST INSTABILITY MAY BE SUFFICIENT FOR FEW ORGANIZED STORMS CAPABLE OF PRODUCING ISOLATED LARGE HAIL AND DAMAGING GUSTS. ...NRN ROCKIES AREA TODAY... A MID LEVEL SHORTWAVE TROUGH OVER ID THIS MORNING WILL CREST THE RIDGE AND MOVE ESEWD OVER MT/NRN WY BY LATER THIS AFTERNOON INTO EARLY TONIGHT. MODEST LOW-LEVEL MOISTURE /SURFACE DEWPOINTS IN THE LOW-MID 50S/ IS PRESENT ACROSS SRN MT AND ERN WY IN THE WAKE OF A FRONTAL PASSAGE...WHILE AFTERNOON TEMPERATURES SHOULD WARM INTO THE 80S WITH DAYTIME HEATING. WEAK-MODERATE INSTABILITY AND VERTICAL SHEAR ARE EXPECTED IN ADVANCE OF THE MID LEVEL WAVE...AND THUNDERSTORMS SHOULD FORM OVER THE HIGH TERRAIN OF SRN MT BY EARLY AFTERNOON. THE MORE INTENSE STORMS MAY DEVELOP SUPERCELL STRUCTURES AND BE CAPABLE OF PRODUCING LARGE HAIL AND GUSTY WINDS. ..THOMPSON/GUYER.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 16:24:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 12:24:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031623 SWODY1 SPC AC 031621 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1121 AM CDT MON JUL 03 2006 VALID 031630Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE MID MS VALLEY...EASTWARD ACROSS THE GREAT LAKES REGION INTO NY/PA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MT/WY/SD... ...WESTERN GREAT LAKES... BAND OF RELATIVELY STRONG WESTERLY FLOW ALOFT REMAINS TODAY FROM THE NORTHERN PLAINS...ACROSS THE GREAT LAKES...AND INTO NEW ENGLAND. WATER VAPOR IMAGERY SHOWS STRONG UPPER TROUGH ROTATING EASTWARD ACROSS NORTHWEST ONTARIO/MN TOWARD WI. SOUTHERLY LOW LEVEL WINDS AHEAD OF SYSTEM ACROSS WI WILL HELP TO TRANSPORT MOISTURE NORTHWARD WITH DEWPOINTS EXPECTED TO BE IN THE MID 60S THIS AFTERNOON. CLOUDS ARE SLOWLY DISSIPATING OVER THIS REGION AS WELL...WHICH SHOULD RESULT IN AFTERNOON MLCAPE VALUES OVER 1500 J/KG. PRESENT INDICATIONS ARE THAT SCATTERED THUNDERSTORMS WILL INTENSIFY THIS AFTERNOON ALONG APPROACHING COLD FRONT ACROSS WI...THEN TRACK EASTWARD ACROSS LAKE MI INTO LOWER MI. VERTICAL SHEAR PROFILES APPEAR FAVORABLE FOR A FEW SUPERCELLS CAPABLE OF DAMAGING WINDS AND HAIL. DESPITE WEAK LOW LEVEL WIND SPEEDS...BACKED FLOW IMMEDIATELY NORTH OF SURFACE BOUNDARY COULD POSE A RISK OF AN ISOLATED TORNADO OVER SOUTHEAST WI/NORTHERN IL THIS AFTERNOON AS WELL. SOUTHERN EXTENT OF THESE STORMS OVER SOUTHERN WI/EASTERN IA WILL LIKELY ORGANIZE AND PROPAGATE EASTWARD ALONG/JUST NORTH OF WEAK SURFACE BOUNDARY ACROSS NORTHERN IL INTO NORTHERN IND/SOUTHERN LOWER MI. HIGH SURFACE DEWPOINT VALUES POOLED ALONG THIS AXIS...COUPLED WITH STRONG WESTERLY FLOW ALOFT...SUGGEST THE POTENTIAL FOR A MORE CONCENTRATED AREA OF SEVERE STORMS THIS EVENING. EASTERN EXTENT OF SEVERE THREAT COULD REACH INTO PARTS OF EASTERN OH OVERNIGHT...DEPENDING ON THE EVOLUTION/ORGANIZATION OF MCS. ...NY/PA/NJ... INCREASING CU FIELD IS NOTED ON VISIBLE SATELLITE IMAGERY ACROSS THIS REGION TODAY. ISOLATED THUNDERSTORMS ARE LIKELY TO FORM DURING THE AFTERNOON...WITH SUFFICIENT INSTABILITY AND VERTICAL SHEAR FOR DAMAGING WINDS AND HAIL IN STRONGER CELLS. PLEASE REFER TO MESOSCALE DISCUSSION NUMBER 1425 FOR FURTHER DETAILS. ...MT/WY... AMPLE LOW/MID LEVEL MOISTURE IS PRESENT OVER SOUTHERN MT/NORTHERN WY TODAY...WHERE STRONG DAYTIME HEATING SHOULD RESULT IN MODERATE INSTABILITY OVER THE MOUNTAINS. SCATTERED AFTERNOON THUNDERSTORMS ARE EXPECTED THROUGHOUT THIS REGION...WITH ISOLATED CELLS CAPABLE OF DAMAGING WINDS AND HAIL. VERTICAL SHEAR IS RATHER WEAK IN THIS AREA...SUGGESTING SEVERE THREAT MAY BE LOCALIZED. ..HART/TAYLOR.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 19:31:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 15:31:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031930 SWODY1 SPC AC 031929 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0229 PM CDT MON JUL 03 2006 VALID 032000Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VALLEY EWD INTO NY STATE AND SWD INTO VA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN ROCKIES... ...UPPER MS VALLEY/GREAT LAKES... WATER VAPOR IMAGERY SHOWS AN UPPER LOW MOVING SLOWLY EWD ACROSS NRN ONTARIO WITH TRAILING SHORT WAVE TROUGH MOVING SEWD ACROSS THE UPPER MS VALLEY. ASSOCIATED SURFACE COLD FRONT FROM LAKE SUPERIOR ACROSS NWRN WI/SWRN IA/NRN KS WILL CONTINUE MOVING EWD...REACHING AN ERN LAKE SUPERIOR/SRN WI/NWRN MO LINE THIS EVENING AND SWRN ONTARIO TO CENTRAL MO BY 04/12Z. IN THE WARM SECTOR...A BAND OF ELEVATED CONVECTION FROM SRN IA ACROSS NRN IL/NRN IND HAS GENERATED A DIFFERENTIAL HEATING BOUNDARY ALONG ITS SRN EDGE...WHICH IS EXPECTED TO PROVIDE AN ADDITIONAL FOCUS FOR STRONG/SEVERE CONVECTION THIS AFTERNOON AND EVENING. PORTIONS OF THE WARM SECTOR FROM WI INTO PARTS OF IA/IL/IN HAS BECOME MODERATELY UNSTABLE WITH MLCAPE OF 1500-2500 J/KG...IN PART DUE TO HIGHER DEW POINT AXIS FROM IA EWD INTO NRN IN. LATEST VISIBLE IMAGERY SHOWS PRE-COLD FRONTAL CU FIELD BECOMING INCREASINGLY ENHANCED FROM NWRN WI INTO IA WITH STRONG THUNDERSTORMS CURRENTLY DEVELOPING OVER PARTS OF IA. THUNDERSTORMS WILL CONTINUE TO DEVELOP AND INTENSIFY ALONG/AHEAD OF THE COLD FRONT THIS AFTERNOON AS MID/UPPER LEVEL JET STREAK MOVES EWD ACROSS THE UPPER GREAT LAKES...PROVIDING STRONG DEEP LAYER SHEAR /35-50 KT EFFECTIVE SHEAR/ SUPPORTIVE OF SEVERE STORMS...INCLUDING POTENTIAL FOR A FEW SUPERCELLS. THIS ACTIVITY MAY BECOME INCREASINGLY ORGANIZED INTO ONE OR MORE FORWARD PROPAGATING MCS/S THIS EVENING...WHICH WOULD LIKELY SPREAD EWD ACROSS PARTS OF WI/NRN IL/LOWER MI/NRN IN AND POSSIBLY OH TONIGHT WITH THREAT FOR MORE CONCENTRATED REGION OF DAMAGING WIND GUSTS AND OCCASIONAL HAIL. ...LOWER GREAT LAKES INTO MID ATLANTIC STATES... A FEW STRONG/SEVERE STORMS HAVE DEVELOPED FROM NORTH OF LAKE ONTARIO SEWD ACROSS NY STATE...WITHIN INSTABILITY AXIS WHERE MLCAPE IS 1000-1500 J/KG. FLOW ALOFT IS MODERATELY STRONG WITH 500 MB WINDS OF 30-40 KT WHICH IS RESULTING IN SUFFICIENT VERTICAL SHEAR TO AID STORM ORGANIZATION. THIS ACTIVITY IS EXPECTED TO SPREAD EWD/SEWD THROUGH THE EVENING HOURS WITH THREAT FOR DAMAGING WINDS AND HAIL. ...SRN VA AREA... A BAND OF STRONG/SEVERE STORMS IS MOVING EWD/SEWD INTO PARTS OF SRN VA...ALONG SRN EDGE OF MODEST NWLY FLOW ALOFT. CLEAR SKIES AHEAD OF THIS BAND ARE PROMOTING STRONG HEATING/CONTINUED DESTABILIZATION WITH MLCAPE GREATER THAN 1500 J/KG. STEEP LOW LEVEL LAPSE RATES WILL ENHANCE DOWNDRAFT STRENGTH WITH THREAT FOR DAMAGING WIND GUSTS AND HAIL WITH STRONGER CELLS. ...NRN ROCKIES AREA... WATER VAPOR IMAGERY SHOWS A VORTICITY MAX MOVING EWD OVER MT WHICH IS GENERATING A FEW THUNDERSTORMS OVER THE MOUNTAINS OF MT AND NRN WY. STEEP LAPSE RATES AND MODERATE WLY MID LEVEL FLOW SUGGEST THE POSSIBILITY OF A FEW STRONG/SEVERE STORMS THIS AFTERNOON AND EVENING CAPABLE OF PRODUCING A FEW DAMAGING MICROBURSTS AND ISOLATED LARGE HAIL. ..WEISS.. 07/03/2006  From swody1 at goshenarc.org Tue Jul 4 01:00:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 21:00:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040059 SWODY1 SPC AC 040057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT MON JUL 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE GREAT LAKES/MIDWEST INTO OH VALLEY... ...SYNOPSIS... CLOSED UPPER LOW WILL CONTINUE TO MOVE ESEWD ACROSS NRN ONTARIO WITH 30-40 METER HEIGHT FALLS EXPECTED OVER THE GREAT LAKES/OH VALLEY REGION OVERNIGHT. BROAD CYCLONIC FLOW REGIME WILL BE MAINTAINED FROM THE UPPER MS VALLEY THROUGH THE GREAT LAKES/OH VALLEY TO NERN STATES. STRONGER WLY MID LEVEL WINDS /40 KT/ AND STRENGTHENING WSWLY LLJ /35-40 KT/ EXPECTED FROM THE MIDWEST THROUGH THE OH VALLEY. ...GREAT LAKES/MIDWEST INTO OH VALLEY... EARLY EVENING SURFACE ANALYSIS SHOWED A WAVY STATIONARY BOUNDARY EXTENDING FROM OH WNWWD TO NRN IL...AND THEN SWWD INTO SERN IA TO SWRN KS. A COLD FRONT EXTENDING FROM THE ERN U.P. OF MI SWWD THROUGH CENTRAL WI TO NRN IA AND GENERALLY BISECTING NEB FROM NE-SW WILL CONTINUE TO ADVANCE ESE OVERNIGHT AND SHOULD REACH A LINE FROM SRN LOWER MI TO THE IA/MO BORDER BY 12Z TUESDAY. CURRENT OBJECTIVE ANALYSIS INDICATED A VERY UNSTABLE AIR MASS ACROSS ERN IA/SRN WI/NRN IL...WITH MUCH OF THE AIR MASS AHEAD OF THE COLD FRONT AND ALONG THE STATIONARY BOUNDARY EXPECTED TO REMAIN MODERATELY UNSTABLE THROUGH 06Z. INCREASING WNWLY MID LEVEL WINDS WILL MAINTAIN STRONG EFFECTIVE BULK SHEAR VALUES THIS EVENING/OVERNIGHT SUPPORTING ADDITIONAL ORGANIZED STRONG TO SEVERE STORMS ALONG THE PROGRESSIVE COLD FRONT WITH HAIL/STRONG WIND GUSTS THE PRIMARY THREATS. WATER VAPOR IMAGERY INDICATED SEVERAL EMBEDDED IMPULSES TRANSLATING EWD FROM THE LOWER MO VALLEY/MIDWEST THROUGH THE OH VALLEY WITH ONE SUCH FEATURE CURRENTLY LOCATED OVER SRN WI/NRN IL. ASCENT AHEAD OF THIS IMPULSE COMBINED WITH DESTABILIZATION/LOW LEVEL ASCENT ALONG A STRENGTHENING SWLY LLJ OVER IL/IND THIS EVENING SHOULD AID IN AN INCREASE IN THUNDERSTORMS ALONG THE STATIONARY BOUNDARY. THIS TREND IS CURRENTLY INDICATED BY REGIONAL RADARS FROM CENTRAL IL INTO NWRN IND WITH STRONG WIND GUSTS/HAIL AND AN ISOLATED TORNADO THREAT POSSIBLE. THIS LLJ SHOULD VEER TO WLY OVERNIGHT AS IT TRANSLATES EWD INTO THE CENTRAL/UPPER OH VALLEY SUPPORTING A CONTINUED THREAT FOR DAMAGING WINDS EWD INTO OH. ...NRN/CENTRAL HIGH PLAINS... SHORT WAVE TROUGH...CURRENTLY LOCATED OVER CENTRAL MT/NRN WY WILL CONTINUE TO ADVANCE EWD REACHING THE WRN DAKOTAS BY 12Z TUESDAY. ASCENT AHEAD OF THIS FEATURE COMBINED WITH PROGGED INCREASE IN UPSLOPE FLOW INTO SERN MT/ERN WY OVERNIGHT SUGGEST SCATTERED THUNDERSTORMS SHOULD PERSIST AT LEAST THROUGH THE EVENING. EFFECTIVE BULK SHEAR VALUES WILL REMAIN SUFFICIENT FOR ORGANIZED STORMS...BUT WEAK INSTABILITY SHOULD CONTINUE TO LIMIT THE OVERALL SEVERE COVERAGE. ..PETERS.. 07/04/2006  From swody1 at goshenarc.org Tue Jul 4 05:58:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 04 Jul 2006 01:58:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040557 SWODY1 SPC AC 040555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT TUE JUL 04 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NERN AND MID ATLANTIC STATES WWD INTO THE OH VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN WY/SWRN SD/WRN NEB... ...SYNOPSIS... CLOSED UPPER LOW OVER NRN ONTARIO AND ATTENDANT TROUGH EXTENDING ACROSS THE GREAT LAKES WILL MOVE SLOWLY ESEWD WITH BROAD CYCLONIC FLOW CONTINUING FROM THE UPPER MS VALLEY THROUGH THE GREAT LAKES/OH VALLEY REGION INTO THE MID ATLANTIC/NERN STATES. AMPLIFICATION OF GREAT LAKES TROUGH IS EXPECTED LATER TODAY/TONIGHT AS AN UPSTREAM SHORT WAVE TROUGH TRACKS SEWD TOWARD THE WRN GREAT LAKES/MIDWEST AND UPPER RIDGE BUILDS EWD OVER THE NRN HIGH PLAINS/CANADIAN PRAIRIE PROVINCES. MEANWHILE...A COUPLE OF MID LEVEL IMPULSES NOW LOCATED OVER THE ERN PACIFIC /WEST OF CA/ WILL TRACK NNELY WITHIN ERN PERIPHERY OF NERN PACIFIC CLOSED LOW CROSSING THE PACIFIC NORTHWEST THIS FORECAST PERIOD. ...NERN/MID ATLANTIC STATES WWD ACROSS THE OH VALLEY... AT THE SURFACE...A PRE-FRONTAL TROUGH IS EXPECTED TO MOVE SWD ACROSS THE OH VALLEY AND EWD INTO NEW ENGLAND TODAY FOLLOWED BY A COLD FRONT SPREADING EWD THROUGH ERN CANADA AND SEWD ACROSS THE LOWER GREAT LAKES AND MID MS VALLEY. THE COLD FRONT SHOULD EXTEND FROM NEW ENGLAND SWWD THROUGH THE OH VALLEY TO THE SRN PLAINS BY 12Z WEDNESDAY. THUNDERSTORMS SHOULD BE ONGOING AT 12Z TODAY FROM THE MID MS VALLEY TO PARTS OF THE LOWER GREAT LAKES REGION. SURFACE HEATING IS EXPECTED ALONG/S OF THE PRE-FRONTAL TROUGH...AND ALSO WITHIN A RATHER NARROW ZONE ACROSS THE SRN GREAT LAKES REGION IN THE WAKE OF THE MORNING ACTIVITY AND AHEAD OF THE COLD FRONT. DESPITE MODEST LAPSE RATES...THE SURFACE HEATING WITHIN A MOIST AIR MASS WILL RESULT IN MODERATE INSTABILITY. DEEP WSWLY WINDS AT 30-40 KT WILL SUPPORT SUFFICIENT DEEP LAYER SHEAR FOR ORGANIZED STORMS WITHIN THE SLIGHT RISK AREA. STRONG TO SEVERE STORMS SHOULD BE FOCUSED ALONG THE PRE-FRONTAL TROUGH FROM SRN IND/SRN OH TO THE MID ATLANTIC STATES AND NEW ENGLAND THROUGH THE AFTERNOON/EARLY EVENING. THE POTENTIAL FOR SEVERE STORMS IS ALSO EXPECTED ALONG THE PROGRESSIVE COLD FRONT FROM THE LOWER GREAT LAKES/OH VALLEY TO UPSTATE NY/NRN NEW ENGLAND. UNI-DIRECTIONAL TROPOSPHERIC WINDS WITH GENERALLY STRAIGHT HODOGRAPHS SUGGESTS LINE SEGMENTS WITH DAMAGING WINDS SHOULD BE THE PRIMARY THREAT...THOUGH SPLITTING STORMS WILL BE POSSIBLE. ...ERN WY INTO WRN PARTS OF SD/NEB... WEAK MID LEVEL IMPULSES CURRENTLY MOVING ENEWD THROUGH THE NRN INTERMOUNTAIN WEST PER WATER VAPOR IMAGERY ARE PROGGED TO TRACK SEWD ACROSS THE NRN/CENTRAL HIGH PLAINS THIS AFTERNOON. ESELY LOW LEVEL FLOW PROGGED ACROSS THIS REGION AS SURFACE HIGH PRESSURE BUILDS SEWD THROUGH THE MID MO VALLEY WILL ALLOW GREATER MOISTURE TO RETURN NWWD INTO WRN NEB/ERN WY. THIS MOISTURE WILL BE LOCATED BENEATH ERN EXTENT OF STEEP LAPSE RATES BY PEAK HEATING RESULTING IN MODERATE INSTABILITY. MODEST NWLY MID LEVEL WINDS /20-25 KT/ EXPECTED ATOP THE ESELY LOW LEVEL FLOW WILL PROVIDE FAVORABLE DEEP LAYER SHEAR /30-40 KT/ FOR SUPERCELLS WITH HAIL AND DAMAGING WIND GUSTS. THUNDERSTORMS SHOULD INITIALLY DEVELOP ALONG THE HIGHER TERRAIN OF ERN WY/SWRN SD...AND THEN DEVELOP SEWD INTO THE HIGH PLAINS. ...CENTRAL-ERN WA/NRN ORE/ID PANHANDLE... SLY MID LEVEL WINDS ARE PROGGED TO STRENGTHEN ACROSS THE PACIFIC NORTHWEST THIS FORECAST PERIOD AS THE NERN PACIFIC LOW MOVES SLOWLY TO THE ESE AND A COUPLE OF SHORT WAVE TROUGHS TRACK NNEWD ACROSS THIS REGION. PLUME OF MID LEVEL MOISTURE LOCATED WITHIN SSWLY FLOW ALOFT COMBINED WITH STEEP LAPSE RATES AND ASCENT AHEAD OF LEAD SHORT WAVE TROUGH ARE EXPECTED TO SUPPORT THE POTENTIAL FOR HIGH BASED THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. ALTHOUGH DEEP LAYER SHEAR SHOULD INCREASE...MARGINAL INSTABILITY /MLCAPE 500-1000 J/KG/ IS EXPECTED TO LIMIT THE OVERALL SEVERE THREAT. STEEP LAPSE RATES AND DEEP WELL MIXED BOUNDARY LAYER /INVERTED-V THERMODYNAMIC PROFILES/ SUGGESTS THREAT FOR ISOLATED MICROBURSTS AND POSSIBLE HAIL. ..PETERS/GUYER.. 07/04/2006  From swody1 at goshenarc.org Mon Jul 10 05:58:08 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 01:58:08 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100556 SWODY1 SPC AC 100554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT MON JUL 10 2006 VALID 101200Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER OH VALLEY AND NRN APPALACHIANS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN PLAINS...CNTRL PLAINS AND MID-MS VALLEY... ...UPPER OH VALLEY/NRN APPALACHIANS... A SHORTWAVE TROUGH CURRENTLY OVER THE NRN APPALACHIAN MTNS WILL LIFT NEWD THIS MORNING AS ANOTHER GREAT LAKES SHORTWAVE MOVES INTO THE NERN U.S. THIS AFTERNOON. AT THE SFC...A COLD FRONT WILL APPROACH THE REGION TODAY WITH DEWPOINTS AHEAD OF THE BOUNDARY REMAINING NEAR 60 F ACROSS MUCH OF THE NRN APPALACHIAN MTNS. THIS SHOULD ALLOW POCKETS OF MODERATE INSTABILITY TO DEVELOP AS TEMPS WARM IN THE LATE MORNING. THE INCREASING LARGE-SCALE ASCENT AS THE UPPER-TROUGH APPROACHES SHOULD RESULT IN SCATTERED THUNDERSTORM DEVELOPMENT ACROSS NRN NEW ENGLAND...WRN NY...WRN PA AND NRN OH BY EARLY AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW THE STRONGEST SHEAR PROFILES ACROSS WRN NY...PA AND NE OH ASSOCIATED WITH A 40 KT MID-LEVEL JET. THIS COMBINED WITH THE INSTABILITY SHOULD BE SUFFICIENT FOR SEVERE MULTICELL LINE SEGMENTS AND PERHAPS A FEW SUPERCELLS THIS AFTERNOON. COLD AIR ALOFT ASSOCIATED WITH THE UPPER TROUGH AND STEEP LOW-LEVEL LAPSE RATES SHOULD PROMOTE LARGE HAIL AND ISOLATED WIND DAMAGE WITH THE STRONGER CELLS. ...SRN AND CNTRL PLAINS/MID-MS VALLEY... AN UPPER-LEVEL TROUGH CURRENTLY OVER THE HIGH PLAINS WILL MOVE EWD INTO THE CNTRL PLAINS TODAY. A LARGE COMPLEX OF THUNDERSTORMS ONGOING AT THE BEGINNING OF THE PERIOD IS FORECAST TO MOVE NEWD INTO NE KS AND SE NEB DURING THE MORNING ALLOWING STRONG SFC HEATING TO TAKE PLACE IN THE WAKE OF THE MCS. SFC DEWPOINTS IN THE UPPER 60S F ACROSS SRN KS...NRN OK AND SWRN MO SHOULD RESULT IN AN AXIS OF MODERATE INSTABILITY BY EARLY AFTERNOON WITH A CAPPING INVERSION GRADUALLY WEAKENING ACROSS THE REGION. AS A RESULT...SCATTERED TO NUMEROUS THUNDERSTORMS SHOULD DEVELOP AND MOVE EWD DURING THE AFTERNOON AND EVENING. FORECAST SOUNDINGS ACROSS THE SLIGHT RISK AREA SHOW MODERATE VERTICAL SHEAR PROFILES ASSOCIATED WITH A 40-50 KT MID-LEVEL JET. THIS SHOULD BE SUFFICIENT FOR SEVERE MULTICELL LINE SEGMENTS AND ISOLATED SUPERCELLS. ALTHOUGH HAIL WILL BE POSSIBLE WITH THE STRONGER CELLS....THE WARM AIR ALOFT AND STEEP LOW-LEVEL LAPSE RATES SHOULD FAVOR WIND DAMAGE AS THE MAIN SEVERE THREAT. ...NRN ROCKIES... A WELL-DEFINED UPPER-LEVEL TROUGH CURRENTLY JUST OFF THE COAST OF BRITISH COLUMBIA AND WA IS FORECAST TO MOVE INLAND TODAY INTO THE NRN ROCKIES BY THIS AFTERNOON. THE STRONG LARGE-SCALE ASCENT AHEAD OF THE UPPER-TROUGH AND SFC HEATING IN THE HIGHER TERRAIN SHOULD ALLOW SCATTERED THUNDERSTORMS TO DEVELOP BY AFTERNOON. ALTHOUGH FORECAST SOUNDINGS SHOW STEEP LAPSE RATES AND MODERATE VERTICAL SHEAR...INSTABILITY MAY REMAIN WEAK DUE TO SFC DEWPOINTS MOSTLY IN THE 40S F. AS A RESULT...ANY SEVERE THREAT IS EXPECTED TO REMAIN MARGINAL THIS AFTERNOON WITH HAIL AND STRONG WIND GUSTS POSSIBLE WITH THE STRONGER CELLS. ..BROYLES.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 12:33:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 08:33:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101231 SWODY1 SPC AC 101229 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 AM CDT MON JUL 10 2006 VALID 101300Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF NORTHERN ROCKIES... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF OHIO...NEW YORK AND PENNSYLVANIA... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF CENTRAL AND SOUTHERN PLAINS... ...SYNOPSIS... WESTERLIES PRIMARILY ACROSS NRN CONUS WITH SEVERAL S/WVS THAT WILL BE FACTORS IN TODAYS CONVECTIVE ACTIVITY. COLD UPPER LOW NOW OPENING AND HEADING NEWD ACROSS SRN NEW ENGLAND AS NEXT UPPER LOW OVER LAKE HURON HEADS FOR WRN NY BY THIS EVENING. S/WV TROUGH WELL DEFINED ON WATER VAPOR IMAGERY NOW MOVING ONSHORE PAC NW WILL CROSS NRN ROCKIES LATER THIS AFTERNOON AND THEN LIFT NEWD INTO SRN ALBERTA OVERNIGHT AS ANOTHER IMPULSE APPROACHES WA COAST BY 12Z TUE. SOMEWHAT REMOVED FROM PRIMARY WLYS A WEAK MID LEVEL TROUGH CONTINUES SLOWLY EWD ACROSS CENTRAL PLAINS TODAY. WEAK COOL FRONT ACROSS SWRN ONTARIO WSWWD TO SRN IA INTO SRN NEB WILL DRIFT SEWD A LITTLE TODAY WITH SLOW WEAKENING. ...NRN ROCKIES... PERSISTENT OVERNIGHT LIGHTNING NERN OREGON NWD REFLECTS BOTH MOISTURE AND AVAILABLE INSTABILITY IN ADVANCE OF S/WV TROUGH THAT WILL BE CROSSING NRN ROCKIES TODAY. WITH 35-40KT OF DEEP LAYER SHEAR AND LAPSE RATES IN EXCESS OF 8 C/KM...PARAMETERS WILL BE FAVORABLE FOR BOTH MARGINALLY SEVERE HAIL AND DAMAGING WIND GUSTS AS STORMS INTENSIFY OVER HIGHER TERRAIN AHEAD OF TROUGH BY EARLY AFTERNOON. THEREFORE HAVE ADDED A SLIGHT RISK OVER AND W OF MTNS IN PRIMARILY MT. FURTHER E THE DOWNSLOPE FLOW WILL LIMIT BOTH MOISTURE AND INSTABILITY...THUS SEVERE POTENTIAL WILL DECREASE EWD OVER THE PLAINS THIS EVENING. ...NERN U.S... WHILE ISOLATED STRONG/SEVERE STORMS POSSIBLE THRU EARLY THIS AFTERNOON ASSOCIATED WITH UPPER LOW LIFTING NEWD ACROSS SRN NEW ENGLAND...PRIMARY SEVERE THREAT TODAY WILL BE WITH NEXT SYSTEM APPROACHING WRN NY/PA THIS AFTERNOON. COOL AIR ALOFT AND STEEP LAPSE RATES WITH WEAKENING UPPER LOW NOW MOVING ACROSS SRN NH POSES MAINLY A MARGINAL HAIL THREAT BEFORE MOVING OFFSHORE. SUFFICIENT HEATING SHOULD OCCUR THIS AM AHEAD OF FRONTAL ZONE WRN NY/PA TO ALLOW AIR MASS TO DESTABILIZE FOR A SEVERE THREAT GIVEN THE UPPER SUPPORT AND SHEAR THAT WILL BE PROVIDED BY THE APPROACHING TROUGH NOW OVER LH. WITH 30-35KT OF SHEAR AND MLCAPES TO AROUND 1000 J/KG STORMS WILL DEVELOP INTO CLUSTER AND LINE SEGMENTS BY EARLY/MID AFTERNOON WITH ASSOCIATED WIND AND HAIL THREAT. STORMS WILL SPREAD EWD PRIOR TO WEAKENING TO BELOW SVR LEVELS THIS EVENING OVER ERN NY/PA. ...CENTRAL/SRN PLAINS... AIR MASS IS NOW VERY MOIST AHEAD OF WEAK TROUGH MOVING ACROSS CENTRAL PLAINS AS NEAR 70F DEWPOINTS HAVE SPREAD NWD INTO SRN KS/SWRN MO. WITH RATHER WEAK MID LEVEL LAPSE RATES AND WARM TEMPERATURES ALOFT...PRIMARY SEVERE THREAT EXPECTED TO BE CONFINED TO WET MICRO BURSTS WHERE STORMS CAN DEVELOP IN AREAS OF GREATEST AFTERNOON HEATING AND DESTABILIZATION. STRONGEST STORMS WILL MOST LIKELY BE FOCUSED VICINITY OUTFLOW BOUNDARIES FROM THIS MORNINGS ACTIVITY. BOUNDARIES SHOULD BE LOCATED VICINITY KS/OK BORDER INTO SWRN MO. WITH SURFACE TEMPERATURES WARMING THRU THE 90S ACROSS MUCH OF OK...MLCAPES WILL CLIMB ABOVE 2000 J/KG S OF BOUNDARIES. THE 25-30KT OF SHEAR ASSOCIATED WITH THE UPPER TROUGH WILL BE SUFFICIENT FOR A FEW SEVERE STORMS WITH WET DOWNBURSTS THE PRIMARY THREAT GIVEN THE VERY WARM 500 MB TEMPERATURES AROUND -5C. ..HALES/BRIGHT.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 16:18:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 12:18:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101615 SWODY1 SPC AC 101613 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1113 AM CDT MON JUL 10 2006 VALID 101630Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FOR ERN OH/WRN PA/WRN NY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS MAINE.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS WRN MT.... ...OH/WRN PA/WRN NY TODAY... A COMPACT MID LEVEL TROUGH IS MOVING ESEWD OVER SWRN ONTARIO TOWARD NE OH/NW PA/WRN NY. THIS MID LEVEL WAVE IS ACCOMPANIED BY A SURFACE LOW OVER SWRN ONTARIO...AND A COLD FRONT EXTENDING WSWWD ACROSS NW OH AND NRN INDIANA. DEBRIS CLOUDS ASSOCIATED WITH ONGOING CONVECTION OVER NE OH/NW PA WILL TEND TO OVERSPREAD WRN NY AND MAY LIMIT DESTABILIZATION THIS AFTERNOON. FARTHER S/SW...STRONGER SURFACE HEATING AND BOUNDARY LAYER DEWPOINTS IN LOW-MID 60S WILL CONTRIBUTE TO MLCAPE VALUES OF 1000-1500 J/KG THIS AFTERNOON ACROSS OH/WRN PA IN ADVANCE OF THE COLD FRONT. THIS INSTABILITY...COMBINED WITH MODEST /30-40 KT/ 0-6 KM SHEAR...SHOULD SUPPORT A FEW BOWING SEGMENTS AND POSSIBLY MARGINAL SUPERCELL STRUCTURES THIS AFTERNOON. DAMAGING GUSTS AND MARGINALLY SEVERE HAIL WILL BE THE PRIMARY SEVERE THREATS THROUGH LATE AFTERNOON. ...MAINE THIS AFTERNOON... A MID LEVEL WAVE IS EJECTING NEWD FROM NH TOWARD MAINE IN RESPONSE TO THE APPROACHING UPSTREAM TROUGH OVER THE LOWER GREAT LAKES. COOL MID LEVEL TEMPERATURES AND ROUGHLY 7 C/KM MID LEVEL LAPSE RATES OBSERVED IN THE 12Z GYX SOUNDING WILL COMBINE WITH DAYTIME HEATING AND LOWER 60S DEWPOINTS TO SUPPORT AFTERNOON MLCAPE VALUES APPROACHING 1000 J/KG. THOUGH VERTICAL SHEAR WILL REMAIN RATHER WEAK NEAR THE MID LEVEL WAVE AXIS...INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STORMS WITH MARGINALLY SEVERE HAIL THIS AFTERNOON. ...WRN MT THIS AFTERNOON/EVENING... A PRONOUNCED MID LEVEL WAVE AND ASSOCIATED BAROCLINIC ZONE ARE MOVING EWD FROM WA TOWARD THE ID PANHANDLE AND WRN MT. THOUGH LOW-LEVEL MOISTURE IS LIMITED IN ADVANCE OF THIS SYSTEM...SURFACE HEATING WILL RESULT IN STEEP LOW-LEVEL LAPSE RATES AND MLCAPE VALUES NEAR 500 J/KG THIS AFTERNOON ACROSS WRN MT. CONVECTION SHOULD INCREASE BY EARLY AFTERNOON AS THE MID LEVEL TROUGH MOVES EWD OVER THE HIGHER TERRAIN OF WRN MT...WITH A BROKEN BAND OF THUNDERSTORMS EXPECTED TO PROGRESS EWD FROM WRN INTO CENTRAL MT AND WEAKEN LATER THIS EVENING. THE RELATIVELY GREATER INSTABILITY AND STRONGER LOW-MID LEVEL FLOW OVER WRN MT MAY SUPPORT A FEW DAMAGING GUSTS THIS AFTERNOON. ...KS/OK AREA THIS AFTERNOON... A SERIES OF WEAK MID LEVEL SPEED MAXIMA ARE MOVING SLOWLY EWD FROM NRN NM/SRN CO TOWARD KS AND NRN OK. REGIONAL SOUNDINGS REVEAL MOIST PROFILES AND MODEST INSTABILITY...AND SATELLITE IMAGERY SUGGESTS THAT ERN KS AND MUCH OF MO WILL REMAIN CLOUDY THROUGH MUCH OF THE AFTERNOON. THE MOIST/POOR LAPSE RATE PROFILES ARE NOT FAVORABLE FOR LARGE HAIL FORMATION OR WIDESPREAD DAMAGING OUTFLOW WINDS...THOUGH A FEW STRONG OUTFLOW GUSTS WILL BE POSSIBLE IN CONJUNCTION WITH STRONG SURFACE HEATING ON THE EDGE OF THE THICKER CLOUDS AND 25-30 KT FLOW NEAR 700 MB. ATTM...THE OVERALL SEVERE THREAT APPEARS TO BE TOO MARGINAL TO WARRANT A SLIGHT RISK. ..THOMPSON/JEWELL.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 19:58:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 15:58:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101956 SWODY1 SPC AC 101955 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0255 PM CDT MON JUL 10 2006 VALID 102000Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTERNOON ACROSS PARTS OF THE LWR GREAT LAKES/UPR OH VLY.... ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTN ACROSS PARTS OF NRN NEW ENGLAND.... ...NEW ENGLAND... STRONGER MID/UPPER FORCING FOR UPWARD VERTICAL MOTION IS ALREADY SHIFTING TOWARD THE CANADIAN MARITIMES AS MID-LEVEL JET STREAK MIGRATES NORTHEAST OF COASTAL MAINE. HOWEVER...BENEATH MID-LEVEL COLD POCKET...WITH 500 MB TEMPERATURES AROUND -14C...AIR MASS REMAINS POTENTIALLY MODERATELY UNSTABLE ACROSS PARTS OF SOUTHERN/ EASTERN MAINE. THIS MAY STILL SUPPORT A FEW STRONG UPDRAFTS WITH LARGE HAIL POTENTIAL THROUGH LATE AFTERNOON...BUT...OVERALL... SEVERE THREAT SEEMS TO BE DIMINISHING. ...LOWER GREAT LAKES/UPPER OHIO VALLEY... STRONGEST DESTABILIZATION...WITH MIXED LAYER CAPE UP TO AROUND 1500 J/KG...HAS GENERALLY BEEN CONFINED TO THE WESTERN/SOUTHERN PERIPHERY OF DIGGING SHORT WAVE TROUGH...WHERE BETTER MOISTURE INFLUX EXISTS AND LOWER-LEVELS ARE A BIT WARMER. STRONG/ISOLATED SEVERE STORMS WITH LARGE HAIL AND GUSTY WINDS MAY PERSIST THROUGH THE REMAINDER OF THE AFTERNOON IN INSTABILITY AXIS AS IT SLOWLY SHIFTS SOUTH OF THE LOWER GREAT LAKES REGION. ACTIVITY IS EXPECTED TO WEAKEN/DIMINISH FAIRLY QUICKLY THIS EVENING ACROSS THE UPPER OHIO VALLEY...AS BOUNDARY LAYER COOLS. ...SOUTH CENTRAL PLAINS THROUGH THE OZARK PLATEAU... A BROAD TROUGH WITH EMBEDDED SMALL SCALE IMPULSES...WHICH HAS SUPPRESSED SUBTROPICAL RIDGING...CONTINUES TO SHIFT EAST OF THE CENTRAL ROCKIES INTO THE CENTRAL PLAINS. IN A CONDITIONALLY UNSTABLE ENVIRONMENT...LARGE-SCALE FORCING ASSOCIATED WITH THIS FEATURE WILL CONTINUE TO SUPPORT AN EXPANDING AREA OF CONVECTIVE DEVELOPMENT THROUGH THE REMAINDER OF THIS FORECAST PERIOD. STORMS WILL BECOME INCREASINGLY FOCUSED NEAR/JUST NORTH OF LOW-LEVEL THERMAL RIDGE AXIS ON ITS SOUTHERN PERIPHERY...WHERE MIXED LAYER CAPE OF 1000-2000 J/KG AND HIGH PRECIPITABLE WATER WILL SUPPORT VIGOROUS UPDRAFTS. LOCALLY HEAVY RAINFALL SEEMS PRIMARY THREAT...BUT SOME HAIL IS POSSIBLE IN STRONGEST CELLS. 25 TO 30 KT WESTERLY MID FLOW IN THE BASE OF THE UPPER TROUGH IS MOSTLY JUST NORTH OF ENVIRONMENT WITH VERY STEEP LOW-LEVEL LAPSE RATES. AND...WITH A SOUTHWESTERLY LOW-LEVEL JET NOT PROGGED TO DEVELOP/STRENGTHEN UNTIL AFTER DARK SOUTH OF THE KANSAS/OKLAHOMA BORDER INTO THE MISSOURI OZARKS...POTENTIAL FOR DAMAGING WINDS SEEMS LIKELY TO REMAIN LIMITED OR RATHER LOCALIZED. ...NORTHERN ROCKIES... A SIGNIFICANT SHORT WAVE TROUGH EMBEDDED WITHIN THE STRONGER WESTERLIES CONTINUES TO PROGRESS INLAND ACROSS BRITISH COLUMBIA AND THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES. THIS SYSTEM IS TAKING ON AN INCREASING NEGATIVE TILT...BUT STRONGEST FORCING/ DESTABILIZATION APPEARS TO BE COMING FOCUSED NORTH OF THE U.S. BORDER...ACROSS PARTS OF ALBERTA/SASKATCHEWAN. A FEW STRONG STORMS ARE POSSIBLE LATE THIS AFTERNOON/EVENING IN THE LEE OF THE NORTHERN ROCKIES...ACROSS PARTS OF WESTERN/CENTRAL MONTANA...BUT SEVERE POTENTIAL SEEMS MORE LIMITED/ISOLATED THAN EARLIER ANTICIPATED. **FOR MORE SPECIFIC DETAILS CONCERNING ONGOING OR MORE IMMINENT CONVECTIVE THREATS...PLEASE REFER TO LATEST SPC MESOSCALE DISCUSSIONS. ..KERR.. 07/10/2006  From swody1 at goshenarc.org Tue Jul 11 00:55:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 20:55:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 110053 SWODY1 SPC AC 110051 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT MON JUL 10 2006 VALID 110100Z - 111200Z ...NO SVR TSTM AREAS FORECAST... ...UPPER OH VALLEY/NRN APPALACHIANS... LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LOW CENTERED OVER SWRN ONTARIO WITH THE LEADING EDGE OF LARGE-SCALE ASCENT MOVING EWD ACROSS WRN NY AND WRN PA. SCATTERED THUNDERSTORMS ARE ONGOING ACROSS THE REGION JUST AHEAD OF THE UPPER-TROUGH INCLUDING A LINE OF STRONG STORMS OVER WRN NY. ALTHOUGH SHEAR PROFILES REMAIN ADEQUATE FOR ORGANIZED STORMS...INSTABILITY SHOULD BEGIN TO STEADILY DECREASE OVER THE NEXT FEW HOURS ACROSS THE REGION. FOR THIS REASON...ANY MARGINAL SEVERE THREAT FOR HAIL AND STRONG WIND GUSTS SHOULD QUICKLY DIMINISH THIS EVENING. ...SRN PLAINS/OZARK PLATEAU... AN UPPER-TROUGH OVER THE SRN AND CNTRL PLAINS WILL CONTINUE TO MOVE EWD THIS EVENING SUPPORTING A LARGE MCS OVER OK...NW AR AND SRN MO. ALTHOUGH REGIONAL PROFILERS CURRENTLY SHOW VERTICAL SHEAR PROFILES ADEQUATE FOR SEVERE STORMS...INSTABILITY SHOULD CONTINUE TO DECREASE OVER THE NEXT FEW HOURS. FOR THIS REASON...THE POTENTIAL FOR WIND GUSTS WITH THE STRONGER CELLS EMBEDDED IN THE LINE SHOULD GRADUALLY DIMINISH. ..BROYLES.. 07/11/2006  From swody1 at goshenarc.org Tue Jul 11 05:57:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 11 Jul 2006 01:57:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 110556 SWODY1 SPC AC 110554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT TUE JUL 11 2006 VALID 111200Z - 121200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...OZARK PLATEAU AND LOWER OH VALLEY... ...SRN PLAINS/OZARK PLATEAU/LOWER OH VALLEY... AN UPPER-LEVEL TROUGH OVER THE SRN PLAINS IS FORECAST TO MOVE VERY SLOWLY EWD TONIGHT INTO TUESDAY. AT THE SFC...A COLD FRONT WILL MOVE SWD ACROSS KS...MO AND IL DURING THE DAY WITH SFC DEWPOINTS SOUTH OF THE BOUNDARY IN THE UPPER 60S AND LOWER 70S F. THE HIGH SFC DEWPOINTS COUPLED WITH STRONG SFC HEATING WILL RESULT IN AN AXIS OF MODERATE INSTABILITY EXTENDING ENEWD FROM THE TX PANHANDLE ACROSS OK INTO SCNTRL MO AND CNTRL IL. AS THE CAP WEAKENS AND LOW-LEVEL CONVERGENCE INCREASES SOUTH OF THE FRONT...SCATTERED TO NUMEROUS THUNDERSTORMS SHOULD INITIATE IN THE EARLY AFTERNOON AND MOVE ESEWD ACROSS THE REGION. FORECAST SOUNDINGS TUESDAY AFTERNOON FROM THE SRN PLAINS TO THE LOWER OH VALLEY SHOW MAINLY UNIDIRECTIONAL WIND PROFILES WITH SUBSTANTIAL SPEED SHEAR IN THE LOWER TO MID-LEVELS. THIS SHOULD RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR SEVERE MULTICELL LINES AND POSSIBLY ISOLATED SUPERCELLS. WIND DAMAGE WILL BE MOST LIKELY WITH LINE SEGMENTS AS LOW-LEVEL LAPSE RATES STEEPEN SOUTH OF THE FRONT IN THE MID TO LATE AFTERNOON. THE WIND DAMAGE POTENTIAL MAY BECOME ENHANCED ACROSS PARTS OF THE SRN PLAINS WHERE FORECAST SOUNDINGS SHOW INVERTED-V THERMODYNAMIC PROFILES. LARGE HAIL WILL BE MOST LIKELY FROM CNTRL IL EXTENDING SWWD ACROSS MO INTO NRN OK WHERE MID-LEVEL TEMPS ARE FORECAST TO BE RELATIVELY COLDER THAN AREAS TO THE SOUTHWEST. ...NEW ENGLAND... LATEST WATER VAPOR IMAGERY SHOWS A WELL-DEFINED SHORTWAVE TROUGH OVER WRN NY AND CNTRL PA. THE TROUGH IS FORECAST TO MOVE ENEWD INTO NEW ENGLAND WITH STRONG LARGE-SCALE ASCENT SUPPORTING SCATTERED THUNDERSTORM DEVELOPMENT IN THE NRN APPALACHIAN MTNS THIS AFTERNOON. FORECAST SOUNDINGS THIS AFTERNOON IN NEW ENGLAND SHOW MODERATE VERTICAL SHEAR PROFILES FROM SRN MAINE SWD TO THE NEW YORK CITY AREA ASSOCIATED WITH A 40 KT MID-LEVEL JET. THIS SHOULD BE SUFFICIENT FOR ORGANIZED THUNDERSTORMS THIS AFTERNOON IF ENOUGH INSTABILITY DEVELOPS AHEAD OF THE TROUGH. HOWEVER...CLOUD COVER ASSOCIATED WITH THE UPPER-TROUGH MAY HAMPER DESTABILIZATION SOMEWHAT TODAY. AS A RESULT...ANY SEVERE THREAT THAT DEVELOPS IS EXPECTED TO REMAIN MARGINAL ATTM. ..BROYLES.. 07/11/2006  From swody1 at goshenarc.org Wed Jul 12 12:43:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 08:43:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121241 SWODY1 SPC AC 121239 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 AM CDT WED JUL 12 2006 VALID 121300Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF NERN U.S.... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT AND ADJACENT HIGH PLAINS... ...SYNOPSIS... MID-SUMMER LARGE SCALE PATTERN OVER CONUS WITH STRONGER WLYS CONFINED TO NEAR CANADIAN BORDER. GREATER SEVERE THUNDERSTORM THREAT TODAY WILL BE ASSOCIATED WITH THE RATHER BROAD TROUGH AND ASSOCIATED WIND MAX MOVING ACROSS THE NERN U.S. AND A DEAMPLIFYING S/WV MOVING ACROSS NRN ROCKIES THIS AFTERNOON. ...NERN U.S... A VERY MOIST/TROPICAL-LIKE AIR MASS WILL SPREAD ACROSS NERN U.S. TODAY. SURFACE LOW LOCATED N OF DTW WAS ASSOCIATED WITH A TROUGH MOVING THRU GREAT LAKES AND FORECAST TO TRACK EWD ACROSS NY AND WRN NEW ENGLAND THIS AFTERNOON AND EVENING. SOUTH OF THE SURFACE LOW A BAND OF 30-40KT LOW THROUGH MID LEVEL FLOW WILL SPREAD EWD FROM UPPER OH VALLEY TO SRN NEW ENGLAND. EXTENSIVE CLOUDINESS WILL SLOW HEATING MUCH OF NERN U.S...HOWEVER SHEAR PROFILES WILL BECOME FAVORABLE FOR BOTH DEVELOPMENT OF CONVECTIVE LINE SEGMENTS AND LOW TOPPED SUPERCELLS NEAR AND SOUTH OF THE SURFACE LOW TRACK. GIVEN HIGH MOISTURE...EXPECT POCKETS OF SURFACE HEATING OCCURRING IN WAKE OF CURRENT LARGE AREA OF PCPN NOW MOVING EWD NY/PA TO ALLOW AN INCREASE IN MLCAPE TO 1500 J/KG...PARTICULARLY PA SWD. MODEL FORECAST SOUNDINGS INDICATE 20-30KT OF SFC-1KM SHEAR AND LCLS LESS THAN 1KM WILL SUPPORT TORNADOES LATER THIS AFTERNOON ACROSS PA AND INTO SERN NY IF SUFFICIENT INSTABILITY DEVELOPS. ADDITIONALLY...30-40KT STEERING FLOW SHOULD PROMOTE FORMATION OF SHORT LINE SEGMENTS WITH AN ENHANCED POTENTIAL FOR WIND DAMAGE FROM CENTRAL PA EWD INTO PARTS OF SRN NEW ENGLAND BY THIS EVENING. SRN LIMIT OF ANY ORGANIZED SEVERE THREAT WILL BE ALONG SRN FRINGE OF STRONGER MID LEVEL FLOW. LEE TROUGH CURRENTLY DELMARVA ALONG WITH HIGH THETA-E AIR MASS WILL PROVIDE SOME ENHANCEMENT OF SURFACE CONVERGENCE THIS AREA WHERE MLCAPES WITH SFC TEMPS AOA 90F COULD REACH TO AOA 2000 J/KG. THIS WILL INCREASE POTENTIAL FOR WET MICRO-BURSTS. ...MT AND WRN ND... AS STRONGER MID LEVEL FLOW SPREADS EWD WITH PASSAGE OF THE S/WV TROUGH HEADING EWD FROM OR/WA...POTENTIAL FOR SEVERE THUNDERSTORMS WILL INCREASE THIS AFTERNOON HIGHER TERRAIN CENTRAL MT. WHILE INSTABILITY/MOISTURE WILL BE SOMEWHAT LIMITED...THE STEEP LAPSE RATES COUPLED WITH SFC-6KM SHEAR OF 35-40KT WILL SUPPORT HIGH BASED MULTICELLULAR STORM DEVELOPMENT. PREDOMINANT THREAT WILL BE DAMAGING WINDS...HOWEVER MARGINALLY SEVERE HAIL IS ALSO LIKELY WITH STRONGER UPDRAFTS. ACTIVITY WILL SPREAD ACROSS NRN HIGH PLAINS INTO TONIGHT...WITH CONTINUING SEVERE POTENTIAL AFTER DARK. ..HALES/CARBIN.. 07/12/2006  From swody1 at goshenarc.org Wed Jul 12 16:18:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 12:18:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121615 SWODY1 SPC AC 121614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT WED JUL 12 2006 VALID 121630Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM THE OH VALLEY TO INTERIOR SRN NEW ENGLAND.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FOR MT AND WRN ND.... ...NY/PA TO NRN KY THROUGH THIS EVENING... A SURFACE LOW AND ASSOCIATED MID LEVEL WAVE OVER SWRN ONTARIO WILL MOVE EWD ACROSS CENTRAL NY THROUGH TONIGHT. VERY MOIST PROFILES ARE PRESENT IN ADVANCE OF THIS SYSTEM ACROSS PA/NY...WITH WIDESPREAD CLOUDS/RAINFALL ACROSS CENTRAL PA AND MUCH OF NY EXPECTED TO LIMIT SURFACE HEATING. HOWEVER...A FEW BREAKS IN THE CLOUDS ARE PRESENT OVER E/SE PA INVOF A WEAK LEE TROUGH...WITH LOWER 70 DEWPOINTS SPREADING NWD ACROSS THIS AREA. THIS RICH MOISTURE AND TEMPERATURES IN THE 70S ACROSS SRN NY AND AT LEAST MID 80S ERN PA/NJ WILL CONTRIBUTE TO AFTERNOON MLCAPE VALUES OF 500-1000 J/KG. THOUGH INSTABILITY WILL BE MARGINAL IN THE TROPICAL TYPE ENVIRONMENT...FORECAST WIND PROFILES SUGGEST THE POTENTIAL FOR SUPERCELLS GIVEN EFFECTIVE BULK SHEAR OF 30-40 KT AND 0-1 KM SRH IN EXCESS OF 200 M2/S2 ACROSS NE PA AND SE NY THIS AFTERNOON. THE MORE FOCUSED THREAT AREA SHOULD BE E OF THE LEE TROUGH AND ALONG THE SRN FRINGE OF THE THICKER CLOUDS THAT ARE REINFORCING A WEAK BOUNDARY ACROSS SRN NY/NE PA. CLOUD BREAKS TO THE S SHOULD ALLOW A FEW DISCRETE STORMS TO FORM IN THE LARGER AREA OF CONVECTION...AND A FEW TORNADOES MAY OCCUR GIVEN THE RICH LOW-LEVEL MOISTURE AND PRONOUNCED LOW-LEVEL SHEAR. FARTHER SW...REGIONAL SOUNDINGS AND VWP/S REVEAL A BELT OF 30-40 KT WSWLY FLOW IN THE 1-3 KM AGL LAYER FROM KY TO PA. MEANWHILE...SURFACE HEATING/DESTABILIZATION ALONG THE SERN FRINGE OF THE THICKER CLOUDS WILL ALLOW THE DEVELOPMENT OF MODERATE INSTABILITY THIS AFTERNOON. THE STEEPER LOW-LEVEL LAPSE RATES AND BELT OF STRONGER LOW-LEVEL FLOW SHOULD BE FAVORABLE FOR A FEW STORMS WITH DAMAGING OUTFLOW WINDS THIS AFTERNOON. ...NRN HIGH PLAINS THIS AFTERNOON/TONIGHT... A MID LEVEL SHORTWAVE TROUGH OVER ERN WA/ORE AND WRN ID THIS MORNING WILL EJECT ENEWD TOWARD ERN MT AND THE SRN PRAIRIE PROVINCES BY EARLY THURSDAY. IN ADVANCE OF THIS TROUGH...A SURFACE LOW NOW IN E CENTRAL MT SHOULD DEVELOP NEWD TOWARD SE SASKATCHEWAN...WHILE BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 60S SPREAD NWD ACROSS THE DAKOTAS. FARTHER W ACROSS MT...THE LOW-LEVELS ARE QUITE DRY ACCORDING THE SURFACE OBSERVATIONS AND 12Z SOUNDINGS. HIGH-BASED CONVECTION MAY MOVE EWD/NEWD OFF THE HIGHER TERRAIN OF SW MT THIS AFTERNOON AS THE MID LEVEL WAVE APPROACHES. DESPITE WEAK INSTABILITY...DEEP INVERTED-V PROFILES COULD SUPPORT A FEW DAMAGING GUSTS ACROSS SW/CENTRAL MT FROM MID-LATE AFTERNOON. OTHER THUNDERSTORMS MAY ALSO FORM THIS AFTERNOON ALONG THE LEE TROUGH ACROSS THE WRN DAKOTAS. INSTABILITY WILL BE SOMEWHAT STRONGER THIS AREA COMPARED TO MT GIVEN AFTERNOON BOUNDARY LAYER DEWPOINTS IN THE 50S...AND VERTICAL SHEAR SHOULD BECOME AT LEAST MARGINALLY FAVORABLE FOR ORGANIZED SEVERE STORMS AS LOW-MID LEVEL FLOW INCREASES IN ADVANCE OF THE MID LEVEL WAVE APPROACHING MT. ...TX PANHANDLE/WRN OK THIS AFTERNOON/EVENING... A WEAK MID LEVEL WAVE OVER THE NRN TX PANHANDLE WILL MOVE SLOWLY EWD TOWARD WRN OK. STRONG SURFACE HEATING IS EXPECTED ACROSS THE TX PANHANDLE IN THE WAKE OF SCATTERED EARLY MORNING CONVECTION...WITH THE STRONGER SURFACE HEATING IN OK ALONG AND S OF I-40. AFTERNOON TEMPERATURES OF 95-100 F WILL RESULT IN STEEP LOW-LEVEL LAPSE RATES AND MODERATE INSTABILITY...WHILE ROUGHLY 25 KT WLY/WNWLY MID LEVEL FLOW WILL PERSIST AROUND THE SRN PERIPHERY OF THE TX PANHANDLE WAVE. SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON...WITH THE POTENTIAL FOR SOME ORGANIZATION TO MULTICELL CLUSTERS. THE STRONGEST STORMS MAY PRODUCE LOCALLY STRONG/DAMAGING DOWNBURSTS AND MARGINALLY SEVERE HAIL. ..THOMPSON/GUYER.. 07/12/2006  From swody1 at goshenarc.org Wed Jul 12 20:03:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 16:03:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121959 SWODY1 SPC AC 121958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT WED JUL 12 2006 VALID 122000Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS SRN PARTS OF THE OH VALLEY INTO THE MID ATLANTIC...NERN U.S. AND SRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN ROCKIES INTO THE NRN HIGH PLAINS... ...NERN U.S. THROUGH SRN NEW ENGLAND AREA... A WARM FRONT EXTENDS FROM SRN NEW ENGLAND WWD THROUGH CNTRL NY TO A SURFACE LOW OVER THE LOWER GREAT LAKES. RICH LOW LEVEL MOISTURE EXISTS NEAR AND S OF FRONT WITH DEWPOINTS NEAR 70. MOIST...TROPICAL DEEP LAYER PROFILES WITH WIDESPREAD CLOUDS AND POOR MID LEVEL LAPSE RATES HAVE RESULTED IN MARGINAL INSTABILITY. SOME BOUNDARY LAYER WARMING HAS DEVELOPED ALONG SRN EDGE OF THICKER CLOUD SHIELD FROM ERN PA THROUGH NJ AND EXTREME SRN NEW ENGLAND WITH MLCAPE FROM 500 TO 1000 J/KG. SHORTWAVE TROUGH AND ATTENDANT SURFACE LOW OVER THE GREAT LAKES WILL MIGRATE ENEWD ALONG THE LOW LEVEL BAROCLINIC ZONE TOWARD ENGLAND THIS AFTERNOON AND EVENING. AS THIS OCCURS A 40+ KT LOW LEVEL JET WILL STRENGTHEN NEWD INTO THE NERN U.S. AND SRN NEW ENGLAND WITH INCREASING LOW LEVEL SHEAR PROFILES. A FEW STORMS WITH SUPERCELL STRUCTURES HAVE ALREADY BEEN OBSERVED IN WARM SECTOR FROM NRN NJ INTO SERN NY AND SRN NEW ENGLAND. ADDITIONAL STORMS MAY DEVELOP THE REMAINDER OF THIS AFTERNOON INTO THE EVENING AS THE BOUNDARY LAYER CONTINUES TO DESTABILIZE. STRENGTHENING LOW LEVEL SHEAR WILL MAINTAIN A THREAT FOR A FEW SUPERCELLS WITH LOW LEVEL MESOCYCLONES AND ISOLATED TORNADOES INTO THE EARLY EVENING. ...SRN OH AND TN VALLEY THROUGH MID ATLANTIC AREAS... SEVERAL MULTICELL CLUSTERS CONTINUE DEVELOPING ALONG NUMEROUS OUTFLOW BOUNDARIES AND IN ASSOCIATION WITH REMNANT MCVS FROM PARTS OF TN...KY AND INTO WV AND NRN VA. THE ATMOSPHERE HAS BECOME MODERATELY UNSTABLE IN THESE AREAS OWING TO AMPLE SURFACE HEATING. PRIMARY THREAT WILL CONTINUE TO BE ISOLATED DAMAGING WIND GUSTS WITH THE STRONGER STORMS THROUGH EARLY EVENING. ...ERN ID...MT THROUGH WRN ND... SCATTERED STORMS ARE CURRENTLY DEVELOPING OVER THE HIGHER TERRAIN OF SWRN MT INTO SERN ID WITHIN ZONE OF ASCENT ACCOMPANYING A SHORTWAVE TROUGH ADVANCING EWD THROUGH THE NRN ROCKIES. ACTIVITY WILL BEGIN TO SPREAD EWD INTO THE HIGH PLAINS OF MT WHERE TEMPERATURES HAVE WARMED INTO THE 90S AND DEWPOINTS HAVE MIXED INTO THE 50S WITH RESULTING INVERTED-V BOUNDARY LAYER PROFILES AND STEEP LAPSE RATES. INSTABILITY IS SOMEWHAT LIMITED OWING TO THE MODEST LOW LEVEL MOISTURE. THIS SUGGESTS THE PRIMARY THREAT WILL BE ISOLATED DAMAGING WIND. HOWEVER MARGINALLY SEVERE HAIL COULD ALSO ACCOMPANY THE STRONGER STORMS. FARTHER EAST RICHER LOW LEVEL MOISTURE EXISTS ACROSS THE CNTRL DAKOTAS...BUT STRONG MIXING HAS RESULTED IN DEWPOINTS FALLING INTO THE 40S AND 50S OVER THE WRN DAKOTAS. A SURFACE BOUNDARY EXTENDS FROM WRN SD SWWD INTO ERN MT. A LEE TROUGH EXTENDS NWD THROUGH WRN SD INTO SWRN ND. STRONG HEATING AND MIXING WITH TEMPERATURES AROUND 100 HAS WEAKENED THE CAP IN THIS AREA...AND THUNDERSTORMS ARE IN THE PROCESS OF DEVELOPING ALONG THESE BOUNDARIES. INVERTED-V PROFILES WILL PROMOTE THE THREAT OF ISOLATED DAMAGING WIND WITH THIS ACTIVITY. MODERATE INSTABILITY AND VERY STEEP LAPSE RATES WILL ALSO SUPPORT A THREAT FOR HAIL. ...CNTRL PLAINS... REFER TO SWOMCD 1489. ..DIAL.. 07/12/2006  From swody1 at goshenarc.org Thu Jul 13 00:59:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 20:59:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130058 SWODY1 SPC AC 130056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT WED JUL 12 2006 VALID 130100Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF NEW ENGLAND AND THE MID-ATLANTIC... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...MID-ATLANTIC/SRN NEW ENGLAND... LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE TROUGH OVER SWRN ONTARIO EXTENDING SSWWD INTO THE UPPER OH VALLEY. AHEAD OF THE TROUGH...LARGE-SCALE ASCENT ACROSS THE NEW ENGLAND AND MID-ATLANTIC STATES IS SUPPORTING SCATTERED STRONG THUNDERSTORMS. THE STRONGEST STORMS ARE LOCATED ALONG THE WRN EDGE OF MODERATE INSTABILITY ACROSS SERN PA. THE INSTABILITY SHOULD SUSTAIN STRONG UPDRAFTS ACROSS THE REGION FOR A FEW MORE HOURS. REGIONAL WSR-88D VWPS CURRENTLY SHOW 0-6 KM SHEAR VALUES AROUND 30 KT ACROSS NJ WHICH COMBINED WITH STRONG LOW-LEVEL FLOW ASSOCIATED WITH A 40-45 KT LOW-LEVEL JET OVER SRN PA SHOULD CONTINUE A THREAT FOR WIND DAMAGE WITH THE STRONGER CELLS. WIND DAMAGE AND POSSIBLY HAIL WILL BE MOST LIKELY WITH THE MORE-ORGANIZED MULTICELL LINE SEGMENTS. ...NRN PLAINS... WATER VAPOR AND RUC ANALYSIS SHOW SOUTHWEST FLOW IN PLACE ACROSS THE NRN PLAINS WITH A SHORTWAVE TROUGH EMBEDDED IN THE FLOW OVER THE WRN DAKOTAS. AN MCS IS CURRENTLY ONGOING JUST AHEAD OF THE SHORTWAVE WHERE ASCENT IS MAXIMIZED DUE TO LARGE-SCALE ASCENT AND LIFT ASSOCIATED WITH A 35-40 KT LOW-LEVEL JET. OBJECTIVE ANALYSIS CURRENTLY SHOWS AN AXIS OF MODERATE INSTABILITY EXISTS FROM CNTRL SD EXTENDING NNEWD ACROSS CNTRL ND INTO SRN MANITOBA WHERE MLCAPE VALUES RANGE FROM 1500-3000 J/KG. THE INSTABILITY SHOULD MAINTAIN STRONG UPDRAFTS AS STORMS DRIFT NEWD INTO NCNTRL ND THIS EVENING. MODERATE VERTICAL SHEAR AND STEEP MID-LEVEL LAPSE RATES EVIDENT ON FORECAST SOUNDINGS SHOULD CONTINUE A THREAT FOR LARGE HAIL WITH THE STRONGER CELLS. WIND DAMAGE WILL ALSO BE POSSIBLE WITH MULTICELL LINE SEGMENTS AS THE LOW-LEVEL JET INCREASES THIS EVENING. ...SRN PLAINS/OZARK PLATEAU... SEVERAL SMALL THUNDERSTORM CLUSTERS ARE ONGOING ACROSS THE SRN PLAINS AND OZARK PLATEAU. THE STRONGEST STORMS ARE LOCATED ALONG AN INSTABILITY AXIS FROM CNTRL KS EXTENDING SEWD INTO ERN OK AND WRN AR. ALTHOUGH REGIONAL PROFILES SHOW RELATIVELY WEAK WIND SHEAR PROFILES (0-6 KM SHEAR 10-20 KT)...MODERATE TO STRONG INSTABILITY AND STEEP LOW-LEVEL LAPSE RATES MAY BE SUFFICIENT FOR A MARGINAL WIND DAMAGE THREAT OVER THE NEXT FEW HOURS. ...ERN WA... A SMALL THUNDERSTORM COMPLEX IS CURRENTLY ONGOING IN ERN WA IN A REGION OF WIDESPREAD LARGE-SCALE ASCENT ASSOCIATED WITH A PACIFIC NORTHWEST UPPER-LEVEL TROUGH. OBJECTIVE ANALYSIS SHOWS AN AXIS OF INSTABILITY OVER ERN WA WITH MLCAPE VALUES AROUND 750 J/KG WITH STEEP LAPSE RATES EXCEEDING 8.5 C/KM. THIS ALONG WITH RELATIVELY COLD 500 MB TEMPS AROUND -15 C SHOULD BE FAVORABLE FOR HAIL OVER THE NEXT FEW HOURS. ..BROYLES.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 06:05:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 02:05:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130602 SWODY1 SPC AC 130601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT THU JUL 13 2006 VALID 131200Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE GREAT PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF VA...WV AND NRN NC... ...GREAT PLAINS... A NRN ROCKIES UPPER-TROUGH IS FORECAST TO MOVE QUICKLY EWD ACROSS THE HIGH PLAINS INTO THE NRN AND CNTRL PLAINS THIS AFTERNOON. LARGE-SCALE ASCENT WILL RAPIDLY INCREASE ACROSS THE PLAINS WITH A LINE OF THUNDERSTORMS QUICKLY DEVELOPING ALONG THE WRN EDGE OF AN AXIS OF MODERATE TO STRONG INSTABILITY BY MID-AFTERNOON. FORECAST SOUNDINGS SHOW INCREASING VERTICAL SHEAR PROFILES AS A 40-50 KT MID-LEVEL JET NOSES INTO THE REGION. IN ADDITION...0-6 KM SHEAR VALUES BETWEEN 30 AND 40 KT AS SHOWN ON FORECAST SOUNDINGS SUGGEST SEVERE MULTICELL LINE SEGMENTS AND/OR SUPERCELLS WILL BE POSSIBLE AS STORMS INCREASE IN COVERAGE LATE THIS AFTERNOON. ALTHOUGH THE MODELS DIFFER CONCERNING THE SRN EXTENT OF A LINEAR MCS...THE WRF MODEL SEEMS REASONABLE DEVELOPING A LINE FROM ERN SD EXTENDING SWD ACROSS ERN NEB. LOW-LEVEL LAPSE RATES ARE FORECAST TO BE VERY STEEP (0-3 KM LAPSE RATES > 9.0 C/KM) WHICH WILL LIKELY ENHANCE THE WIND DAMAGE POTENTIAL. VERY STRONG WIND GUSTS WILL BE POSSIBLE WITH ANY BOWING SEGMENTS IN THE LINE. HAIL WILL ALSO BE LIKELY WITH THE STRONGER ELEMENTS IN THE LINE AND THE GREATEST POTENTIAL FOR LARGE HAIL SHOULD EXIST WITH SUPERCELLS THAT DEVELOP AHEAD OF OR EMBEDDED IN THE LINE. THE LINEAR MCS SHOULD MOVE ESEWD ACROSS THE SIOUX FALLS SD AND OMAHA NEB AREAS BY EARLY EVENING LIKELY REACHING WRN IA...NW MO AND NE KS BY LATE EVENING. A SEVERE THREAT MAY CONTINUE OVERNIGHT ESPECIALLY CONSIDERING STRONG INSTABILITY IS FORECAST TO BE IN PLACE THROUGH THIS EVENING. FURTHER SOUTH ACROSS SW KS...THE ERN TX PANHANDLE AND NW OK...THE MODELS FORECAST WEAKER LARGE-SCALE ASCENT AND A STRONGER CAPPING INVERSION THAN AREAS FURTHER NORTH WHICH SHOULD KEEP THUNDERSTORM COVERAGE MORE ISOLATED. ALTHOUGH THE HAIL POTENTIAL MAY BE LESS DUE TO THE WARMER AIR ALOFT...A POTENTIAL FOR WIND DAMAGE SHOULD STILL EXIST WITH THE STRONGER CELLS DUE TO STEEP LOW-LEVEL LAPSE RATES AND MODERATE VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS. ...VA/NC... WATER VAPOR IMAGERY CURRENTLY SHOWS A SHORTWAVE TROUGH OVER THE OH VALLEY WITH A NOTABLE DRY PUNCH ADVANCING EWD ACROSS NRN IL AND NRN IND ATTM. MODEL FORECASTS MOVE THIS FEATURE EWD ACROSS THE CNTRL APPALACHIAN MTNS TODAY INCREASING LARGE-SCALE ASCENT ACROSS VA AND NRN NC LATE THIS AFTERNOON. SFC DEWPOINTS NEAR 70 F IN THE APPALACHIAN FOOTHILLS AND COASTAL PLAINS SHOULD ALLOW MODERATE TO STRONG INSTABILITY TO DEVELOP BY MIDDAY. SCATTERED THUNDERSTORMS SHOULD INITIATE AND MOVE EWD ACROSS THE REGION DURING THE AFTERNOON AHEAD OF THE APPROACHING SHORTWAVE TROUGH. VERTICAL SHEAR PROFILES ARE FORECAST TO RANGE BETWEEN 20 AND 30 KT AND SHOULD BE STRONGEST IN VA AS THE UPPER-TROUGH APPROACHES. THIS COMBINED WITH THE STRONG INSTABILITY SHOULD BE SUFFICIENT FOR ISOLATED SEVERE THUNDERSTORMS. HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE STRONGER MULTICELL LINE SEGMENTS LATE THIS AFTERNOON INTO EARLY THIS EVENING. ...MID-MS VALLEY... A LARGE WARM SECTOR CURRENTLY EXISTS ACROSS THE MID MS VALLEY WHERE SFC DEWPOINTS ARE IN THE UPPER 60S AND LOWER 70S F. THE LOW-LEVEL MOISTURE SHOULD REMAIN IN PLACE TODAY ALLOWING STRONG INSTABILITY TO DEVELOP AS SFC TEMPS WARM. ALTHOUGH FORECAST SOUNDINGS ACROSS THE REGION SHOW RELATIVELY WEAK SHEAR PROFILES (0-6 KM SHEAR OF 10-20 KT)...THE STRONG INSTABILITY AND STEEP LOW-LEVEL LAPSE RATES SHOULD BE SUFFICIENT FOR A FEW MARGINALLY SEVERE STORMS. STRONG WIND GUSTS WILL BE MOST LIKELY WITH SHORT MULTICELL LINE SEGMENTS NEAR OR JUST AFTER PEAK HEATING. ..BROYLES/GRAMS.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 12:35:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 08:35:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131233 SWODY1 SPC AC 131231 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0731 AM CDT THU JUL 13 2006 VALID 131300Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF PLAINS STATES SWD TO OK... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF THE MID ATLANTIC STATES... ...SYNOPSIS... ENERGY WITH TROUGH NOW ENTERING THE NORTHERN HIGH PLAINS WILL SPLIT AS UPPER HIGH BUILDS NWD THRU INTERIOR WRN U.S. MAIN PORTION OF TROUGH CONTINUES EWD TO UPPER MS VALLEY BY LATE TONIGHT WITH A SRN PORTION HEADING SEWD DOWN THE MO RIVER VALLEY...REACHING MO BY 12Z FRI. A PERSISTENT SLY LOW LEVEL JET OF 20-30 KT CONTINUES TO FEED VERY MOIST AIR NWD THRU THE CENTRAL PLAINS IN ADVANCE OF THE COLD FRONT CURRENTLY LOCATED FROM CENTRAL ND SSWWD TO NEB PANHANDLE. BY MID-AFTERNOON THE COMBINATION OF STRONG HEATING WITH SFC TEMPERATURES TO NEAR 100F NWD INTO NEB AHEAD OF FRONT AND DEWPOINTS WELL INTO THE 60S WILL RESULT IN A VERY TO EXTREMELY UNSTABLE AIR MASS WITH MLCAPES POSSIBLY AOA 4000 J/KG. THE DIRECTIONAL SHEAR WITH LOW LEVEL SLYS AND 20-30KT NWLY MID LEVEL FLOW ACCOMPANYING THE S/WV TROUGH DROPPING SEWD THRU PLAINS...WILL PROVIDE 30-35KT OF DEEP LAYER SHEAR BY MID AFTERNOON. THIS IS MORE THAN SUFFICIENT TO SUPPORT SUPERCELL DEVELOPMENT GIVEN THE AVAILABLE INSTABILITY. BOTH THE NAM AND GFS HAVE A PARTICULARLY STRONG CONVECTIVE SIGNAL ON THE 06Z RUNS BY LATE THIS AFTERNOON OVER ERN NE AND THIS SEEMS REASONABLE GIVEN THE SYNOPTIC CONDITIONS. CAP WILL ERODE SUFFICIENTLY TO ALLOW RAPID INITIATION OF SURFACE BASED THUNDERSTORMS VICINITY FRONTAL ZONE BY LATE AFTERNOON. IN THE EARLY STAGES OF DEVELOPMENT VERY LARGE HAIL IS LIKELY WITH THE MODELS INDICATING RAPID DEVELOPMENT OF A COLD POOL GIVEN THE LARGE DCAPES UPWARDS TO 1500 J/KG OR GREATER IN THE WARM SECTOR. DAMAGING WINDS WILL THEN BE PRIMARY CONCERN AS A POTENTIAL SEVERE MCS PROPAGATES SEWD ACROSS ERN NEB INTO NRN KS AND NWRN MO. WILL RAISE PROBABILITIES OF BOTH WIND AND HAIL HOWEVER WITHHOLD A CATEGORY UPGRADE UNTIL NEXT MODEL RUN LENDS MORE CONFIDENCE IN THE INDICATED SCENARIO OF 06Z SOLUTIONS. SUFFICIENT INSTABILITY AND SHEAR AHEAD OF FRONT NWD TO THE CANADIAN BORDER FOR POTENTIAL SUPERCELLS AND DAMAGING WIND AND HAIL THREAT BY MID AFTERNOON. ...MID ATLANTIC STATES... E/W COLD FRONT ACROSS PA SLOWLY DROPPING SWD PRECEEDED BY A DEEP LAYER OF VERY MOIST AIR WITH PW/S IN EXCESS OF 2 INCHES. SEVERE THREAT IN THE E TODAY WILL MOST LIKELY OCCUR NEAR THE INTERFACE OF THE THICKER CLOUD COVER AND STRONG HEATING S OF FRONT OVER CENTRAL/SRN VA INTO NRN NC. WHILE MLCAPES IN THIS AREA WILL CLIMB TO 2000 J/KG OR MORE...THE WEAK LAPSE RATES AND MARGINAL SHEAR SHOULD CONFINE ANY SEVERE THREAT TO DAMAGING WINDS. THE 20-25KT OF SHEAR SUPPORT MULTICELL AND POSSIBLY LINE SEGMENTS DEVELOPING BY MID AFTERNOON WITH ASSOCIATED POTENTIAL WET MICRO BURSTS. ...MID MISSISSIPPI AND TN VALLEYS... VERY MOIST AND UNSTABLE AIR WILL PREVAIL S OF STATIONARY FRONTAL ZONE FROM THE MID MS VALLEY EWD TO APPALACHIANS. WEAK SHEAR PROFILES WILL BE CONDUCIVE TO PRIMARILY A PULSE SEVERE THREAT. THUS WHILE THERE IS THE POTENTIAL FOR DAMAGING DOWNBURSTS AND LARGE HAIL OVER MUCH OF THIS AREA...COVERAGE WILL BE LIMITED PRECLUDING TRYING TO IDENTIFY A RISK AREA ATTM. ..HALES/GRAMS.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 16:42:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 12:42:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131640 SWODY1 SPC AC 131638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT THU JUL 13 2006 VALID 131630Z - 141200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF THE LWR MO VLY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN DAKS/WRN MN SWD INTO OK AND MO... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE MID ATLANTIC STATES AND SOUTHEAST... ...SYNOPSIS... AN ACTIVE STORM PERIOD EXPECTED OVER THE CNTRL PLNS/LWR MO VLY AS WRN RIDGE REBOUNDS IN WAKE OF PROGRESSIVE SHORTWAVE TROUGH NOW ENTERING THE DAKOTAS. THE TROUGH LIKELY WILL SPLIT...WITH MAIN PORTION CONTINUING E TO THE UPR MS VALLEY BY LATE TONIGHT AS SRN PART DROPS SE ON NERN FRINGE OF RIDGE. ...CNTRL PLNS/LWR MO VLY... A VERY MOIST...VERY WARM BOUNDARY LAYER AIR MASS IS IN PLACE FROM THE CNTRL PLNS/LWR MO VLY NWD IN A NARROWING AXIS TO THE ERN DAKOTAS/WRN MN. STRONG HEATING WILL CONTINUE THROUGH THE AFTERNOON ALONG AND AHEAD OF WEAK COLD FRONT MOVING E/SE ACROSS THE DAKOTAS AND WRN NEB. SUBSTANTIAL HEATING WILL ALSO OCCUR ALONG STATIONARY FRONT EXTENDING ESE FROM ERN NEB INTO CNTRL/SRN IL. STEEPENING LOW LEVEL LAPSE RATES AND QUALITY MOISTURE SUPPLY SHOULD BOOST AFTERNOON SBCAPE TO AOA 4000 J/KG ACROSS A BROAD SWATH FROM CNTRL NEB ESE INTO PARTS OF KS/IA AND NRN MO. DEEP SHEAR ACROSS MDT AND SLGT RISK AREAS WILL INTENSIFY TODAY THROUGH TONIGHT AS MID LEVEL FLOW VEERS AND STRENGTHENS ON SW SIDE OF SHORTWAVE IMPULSE. BY MID TO LATE AFTERNOON...30-40 KT DEEP NWLY SHEAR SHOULD EXTEND FROM SE SD SEWD INTO NRN KS/NW MO. WITH TIME...STRONGER NW FLOW ALOFT SHOULD ALSO SPREAD S TOWARD THE SRN PLNS. OVERALL KINEMATIC/THERMODYNAMIC SETUP SUGGESTS THAT CONTINUED SURFACE HEATING WILL ALLOW SLIGHTLY ELEVATED STORMS NOW OVER NEB AND THE ERN DAKOTAS TO BECOME SURFACE-BASED A BIT LATER THIS AFTERNOON. OTHER STORMS LIKELY WILL FORM INVOF AFOREMENTIONED SURFACE BOUNDARIES NWD INTO THE ERN DAKOTAS. GIVEN DEGREE OF INSTABILITY AND STRENGTHENING SHEAR...CONDITIONS WILL BE FAVORABLE FOR SUSTAINED STORMS AND A FEW SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WET MICROBURSTS...ESPECIALLY IN NEB AND THE LWR MO VLY. THESE STORMS SHOULD FAIRLY QUICKLY MERGE INTO ONE OR TWO LARGE CLUSTERS...WITH FORWARD PROPAGATING SEGMENTS EXTENDING A THREAT FOR WIND/HAIL E/SE INTO PARTS OF KS/MO AND PERHAPS SRN IA BY EARLY THIS EVENING. ISOLATED HIGH WIND-PRODUCING STORMS MAY ALSO FORM INVOF LEE TROUGH IN NW KS...AND ALONG FRONT IN SRN IA. LATER TONIGHT AND EARLY FRIDAY...FORWARD-PROPAGATING CONVECTIVE SEGMENTS MAY EXTEND A THREAT FOR HIGH WIND SWD INTO NRN OK. ...MID ATLANTIC STATES... E/W COLD FRONT ACROSS PA WILL CONTINUE SLOWLY SWD...PRECEEDED BY A DEEP...WARM AND MOIST WLY FLOW INTO VA/NC. DIFFERENTIAL HEATING OCCURRING ALONG PREFRONTAL LINE OF CONVECTIVE DEBRIS...AND OROGRAPHIC INFLUENCE...LIKELY WILL INITIATE STORMS OVER SW VA/ERN TN AND NW NC A BIT LATER THIS AFTERNOON. MLCAPE WILL BE AOA 2000 J/KG...BUT RELATIVELY WEAK LAPSE RATES SHOULD LIMIT INTENSITY OF CONVECTIVE DEVELOPMENT. 20-25KT OF DEEP UNIDIRECTIONAL SHEAR SHOULD SUPPORT MULTICELL LINE SEGMENTS WITH THE POTENTIAL FOR SCATTERED WET MICROBURSTS. ...LWR TN VLY... VERY MOIST AND UNSTABLE AIR WILL PREVAIL S OF STATIONARY FRONTAL ZONE FROM THE MID MS VALLEY E TO APPALACHIANS. WEAK SHEAR WILL BE CONDUCIVE TO PRIMARILY A PULSE SEVERE THREAT. THUS WHILE THERE IS THE POTENTIAL FOR DAMAGING DOWNBURSTS AND LARGE HAIL OVER MUCH OF THIS AREA...COVERAGE SHOULD BE LIMITED. ..CORFIDI/GUYER.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 20:19:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 16:19:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 132016 SWODY1 SPC AC 132015 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0315 PM CDT THU JUL 13 2006 VALID 132000Z - 141200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS SOUTHEASTERN NEBRASKA...NORTHEAST KANSAS...WESTERN IOWA...AND NORTHWEST MISSOURI.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A LARGE PORTION OF THE PLAINS STATES AND INTO THE MIDDLE AND UPPER MS VALLEY REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF VA/NC AND VICINITY... ...THE PLAINS INTO THE MID/UPPER MS VALLEY... VIGOROUS STORMS CONTINUE TO DEVELOP/ORGANIZE INVOF THE MID MO VALLEY...WHILE INCREASING STORM COVERAGE IS EVIDENT NWD INTO WRN MN AS WELL AS SEWD ACROSS ERN MO. AIRMASS HAS BECOME VERY UNSTABLE -- PARTICULARLY ACROSS THE MIDDLE MO VALLEY REGION...WHERE DEWPOINTS IN THE MID 70S BENEATH VERY STEEP LAPSE RATES ALOFT ARE RESULTING IN 2500 TO 4500 J/KG MEAN-LAYER CAPE. WITH 30 KT WNWLY FLOW ALOFT SPREADING EWD INTO THIS REGION BENEATH LOW-LEVEL SLYS...SHEAR REMAINS SUPPORTIVE OF ORGANIZED/SUPERCELL STORMS -- PARTICULARLY GIVEN DEGREE OF INSTABILITY. ALONG WITH POTENTIAL FOR WIDESPREAD/LARGE HAIL...DAMAGING WINDS ARE ALSO EXPECTED AS STORMS CONTINUE TO INCREASE IN COVERAGE AND INTENSITY. ATTM...IT APPEARS THAT MOST SIGNIFICANT SEVERE THREAT WILL EXIST ACROSS SERN NEB EWD INTO IA/NWRN MO AND SWD INTO NERN KS -- WHERE GREATEST COMBINATION OF SHEAR AND INSTABILITY ARE INDICATED. OVERNIGHT...EXPECT AXIS OF GREATEST THREAT TO SHIFT SWD AND EWD -- ACROSS ERN KS AND MO -- AS SWLY LOW-LEVEL JET DEVELOPS AIDING POTENTIAL FOR SEVERAL FORWARD-PROPAGATING MCS TO DEVELOP. ALONG WITH THREAT FOR HAIL...DAMAGING WINDS WILL REMAIN POSSIBLE AS STORMS SPREAD SEWD THROUGH THE END OF THE PERIOD. ...PARTS OF VA/NC AND VICINITY... THUNDERSTORMS CONTINUE TO DEVELOP INVOF SURFACE FRONT/AHEAD OF UPPER SHORT-WAVE TROUGH CROSSING WV/WRN VA ATTM...WITHIN MODERATELY-UNSTABLE AIRMASS. MODERATE/WLY FLOW WITH HEIGHT REMAINS IN PLACE OVER THIS REGION...BUT FLOW ROUGHLY PARALLEL TO THE SURFACE BOUNDARY WILL CONTINUE TO LIMIT SEVERE POTENTIAL. NONETHELESS...POTENTIAL FOR LOCALLY-DAMAGING WINDS WILL CONTINUE WITH STRONGER CELLS PRIOR TO THE ONSET OF DIURNAL BOUNDARY-LAYER STABILIZATION. ..GOSS.. 07/13/2006  From swody1 at goshenarc.org Fri Jul 14 00:57:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 20:57:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140054 SWODY1 SPC AC 140052 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0752 PM CDT THU JUL 13 2006 VALID 140100Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS PARTS OF THE CENTRAL PLAINS AND MID/UPPER MISSISSIPPI VALLEY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF THE SRN MID ATLANTIC COAST.... ...CENTRAL STATES... A SIGNIFICANT SHORT WAVE TROUGH...COMPRISED OF AT LEAST A COUPLE SMALLER SCALE IMPULSES...CONTINUES TO PROGRESS TO THE NORTHEAST OF A SOUTHWESTERN U.S. SUBTROPICAL HIGH CENTER. AS THIS MOTION CONTINUES TONIGHT...MODELS SUGGEST A RIDGE AXIS WILL BUILD TO THE NORTH OF THE HIGH...THROUGH THE CENTRAL ROCKIES/NORTHERN HIGH PLAINS. BULK OF DOWNSTREAM TROUGH WILL SHIFT INTO THE UPPER MISSISSIPPI VALLEY...BUT A SUBSTANTIAL MID-LEVEL JET STREAK/SHORT WAVE TROUGH IS PROGGED TO DIG SOUTH OF THE STRONGER WESTERLIES... THROUGH MUCH OF THE MID/LOWER MISSOURI VALLEY BY 12Z FRIDAY. MOST EXTENSIVE ONGOING CONVECTIVE DEVELOPMENT APPEARS TO BE IN ASSOCIATION WITH FORCING IN THE SOUTHERN PORTION OF THE SHORT WAVE TROUGH. THIS SEEMS LIKELY TO REMAIN THE CASE THROUGH THE NIGHT...SUPPORTED BY MOIST UNSTABLE AIR MASS WHICH IS PREVALENT THROUGH MUCH OF THE PLAINS/MISSISSIPPI AND OHIO VALLEYS. A CLUSTER OF STORMS WITH A SUBSTANTIAL COLD POOL NOW PROGRESSING INTO THE LOWER MISSOURI VALLEY WILL PROBABLY MAINTAIN A RISK OF DAMAGING WINDS/HAIL THROUGH MUCH OF THE EVENING. HOWEVER...TOWARD THE OVERNIGHT HOURS...AS IT APPROACHES THE ST. LOUIS AREA...AND PROGRESSES SOUTHEAST OF KANSAS CITY...COOLING OF BOUNDARY LAYER PROBABLY WILL BEGIN TO MITIGATE SEVERE THREAT. FARTHER WEST...NOCTURNAL STRENGTHENING OF SOUTHERLY LOW-LEVEL JET FROM CENTRAL OKLAHOMA THROUGH EASTERN KANSAS MAY SUPPORT ANOTHER EXPANDING CLUSTER OF STORMS THIS EVENING. MORE STRONGLY HEATED BOUNDARY LAYER ACROSS THE CENTRAL PLAINS WILL BE SLOWER TO COOL...MAINTAINING FAVORABLE ENVIRONMENT FOR SOUTHWARD PROPAGATING COLD POOL WITH DAMAGING WIND POTENTIAL...SOUTH OF INTERSTATE 70 TOWARD THE KANSAS/OKLAHOMA BORDER BY LATE EVENING...PERHAPS THE INTERSTATE 44 CORRIDOR BY THE END OF THE PERIOD. ...SOUTHERN MID ATLANTIC COAST... MAIN UPPER FORCING IS BEGINNING TO SHIFT OFFSHORE...BUT MIXED LAYER CAPE TO 2000 J/KG AHEAD OF SURFACE FRONT MAY MAINTAIN RELATIVELY VIGOROUS CONVECTIVE DEVELOPMENT ACROSS CENTRAL/NORTHEAST NORTH CAROLINA THIS EVENING. ISOLATED DAMAGING WIND GUSTS AND SOME HAIL WILL REMAIN POSSIBLE THROUGH AROUND 03-04Z...BEFORE ACTIVITY DIMINISHES FURTHER WITH CONTINUED BOUNDARY LAYER COOLING. ..KERR.. 07/14/2006  From swody1 at goshenarc.org Fri Jul 14 05:53:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 14 Jul 2006 01:53:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140551 SWODY1 SPC AC 140549 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1249 AM CDT FRI JUL 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EARLY EVE ACROSS PARTS OF THE UPPER GREAT LAKES/LOWER OHIO VALLEY.... SOUTHWESTERN STATES SUBTROPICAL RIDGE REMAINS STRONG...AND IS ALREADY BUILDING NORTHEASTWARD THROUGH THE CENTRAL ROCKIES AND PARTS OF THE NORTHERN HIGH PLAINS. FURTHER EXPANSION EASTWARD ACROSS THE CENTRAL/NORTHERN PLAINS THROUGH THE UPPER HALF OF THE MISSISSIPPI VALLEY IS PROGGED TO OCCUR TODAY...AS A SEASONABLY STRONG MID/UPPER JET...EMANATING FROM THE NORTHEAST PACIFIC... NOSES EASTWARD ALONG/JUST NORTH OF THE CANADIAN/U.S. BORDER. THIS IS EXPECTED TO SUPPORT THE EASTWARD PROGRESSION OF A WEAKENING UPPER TROUGH ACROSS THE GREAT LAKES/LOWER OHIO VALLEY REGION...TO THE SOUTH OF A SOMEWHAT STRONGER BELT OF WESTERLIES ACROSS EASTERN CANADA. ...MISSISSIPPI RIVER EASTWARD... DRYING IN THE WAKE OF UPPER TROUGH MIGRATING OFF THE NORTH ATLANTIC COAST SEEMS LIKELY TO LIMIT CONVECTIVE POTENTIAL ACROSS MUCH OF THE NORTHEAST DURING THIS FORECAST PERIOD. HOWEVER...MOST OTHER AREAS WILL REMAIN VERY MOIST...REFLECTED BY SURFACE DEW POINTS IN THE UPPER 60S/LOWER 70S. NORTH OF FLAT UPPER RIDGE ACROSS THE GULF STATES...CAPPING WILL BE WEAK...LIKELY ALLOWING WIDESPREAD CONVECTIVE DEVELOPMENT WITH DAYTIME HEATING. GUSTY WINDS AND MARGINALLY SEVERE HAIL WILL BE POSSIBLE IN STRONGER UPDRAFT PULSES WHERE CONVECTION FORMS. HOWEVER...SEVERE THREAT MAY BECOME MOST CONCENTRATED FROM PARTS OF THE UPPER MIDWEST INTO THE LOWER OHIO VALLEY. THIS IS WHERE MODELS SUGGEST STRONGEST DESTABILIZATION WILL OCCUR TODAY...WITH MIXED LAYER CAPE UP TO AROUND 3000 J/KG POSSIBLE BY PEAK HEATING...BENEATH REMNANT MID-LEVEL COLD POOL ASSOCIATED WITH WEAKENING UPPER TROUGH. POTENTIAL FOR A LARGE ORGANIZED CONVECTIVE CLUSTER SEEMS LOW...BUT NORTHWESTERLY MID/UPPER FLOW ON WESTERN/SOUTHERN PERIPHERY OF UPPER THERMAL TROUGH MAY CONTRIBUTE TO DEEP LAYER SHEAR AS STRONG AS 25-30KT. THIS WOULD ENHANCE RISK FOR LARGE HAIL IN SCATTERED STORMS ACROSS PARTS OF WISCONSIN/ILLINOIS INTO LOWER MICHIGAN/INDIANA DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. ...SOUTHERN PLAINS INTO OZARK PLATEAU... CONVECTIVE OUTFLOW BOUNDARY FROM ONGOING CONVECTION IS EXPECTED TO STALL ACROSS PARTS OF NORTHERN ARKANSAS/OKLAHOMA EARLY TODAY. SOUTH OF THIS BOUNDARY...LOW-LEVEL THERMAL RIDGE AXIS IS EXPECTED TO BECOME A POSSIBLE FOCUS FOR SCATTERED NEW AFTERNOON THUNDERSTORMS...MOSTLY IN RESPONSE TO STRONG SURFACE HEATING. LATENT INSTABILITY MAY NOT BECOME PARTICULARLY LARGE DUE TO WARM MID-LEVEL ENVIRONMENT...BUT HOT DEEP MIXED BOUNDARY LAYER WITH 30-40 DEGREE TEMPERATURE/DEW POINT SPREADS WILL BE FAVORABLE FOR LOCALIZED DOWNBURSTS. ..KERR.. 07/14/2006  From swody1 at goshenarc.org Fri Jul 14 12:25:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 14 Jul 2006 08:25:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141223 SWODY1 SPC AC 141222 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0722 AM CDT FRI JUL 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS IN THE GREAT LAKES STATES.... ...SYNOPSIS... SHORTWAVE TROUGH...CURRENTLY MOVING INTO WRN WI/NWRN IL...IS FORECAST TO MOVE ESEWD THROUGH THE DAY AND EXTEND FROM SRN LOWER MI SWWD INTO INDIANA BY LATE AFTERNOON. RIDGE OVER THE SWRN STATES WILL BUILD NWD IN THE WAKE OF THE EXITING UPPER TROUGH. A WEAK SURFACE WAVE...ASSOCIATED WITH THE UPPER TROUGH...IS EXPECTED TO BE LOCATED OVER LOWER MI...WITH A WEAK TRAILING BOUNDARY EXTENDING SWWD INTO SRN MO. ...GREAT LAKE STATES... CONVECTION MOVING THROUGH WI THIS MORNING WILL SHIFT EWD THROUGH THE DAY AND MAY GRADUALLY INTENSIFY AS IT ENCOUNTERS AN INCREASINGLY WARMING AND UNSTABLE AIR MASS ACROSS SRN LOWER MI. STORMS ARE ALSO LIKELY TO REDEVELOP WITHIN FORCING LOCATED AHEAD OF UPPER TROUGH AND AN MCV MOVING EWD OUT OF CENTRAL MO INTO IL AND INDIANA DURING THE AFTERNOON HOURS. SURFACE DEW POINTS IN THE UPPER 60S/LOWER 70S SHOULD RESULT IN MLCAPES FROM 2000 TO 3000 J/KG ACROSS THIS REGION BY MID/LATE AFTERNOON. ALTHOUGH MID LEVEL WINDS ARE FORECAST TO INCREASE TO 30 KT...MOSTLY UNIDIRECTIONAL WINDS ABOVE THE BOUNDARY LAYER SHOULD RESULT IN DEEP LAYER SHEAR OF ONLY 20-25KT. HOWEVER...THIS SHEAR AND THE DEGREE OF INSTABILITY WOULD SUPPORT SEVERE MULTICELL STORMS WITH SEVERE WIND/HAIL EVENTS. STORMS SHOULD WEAKEN/DISSIPATE AFTER SUNSET AS THE BOUNDARY LAYER STABILIZES. ...SOUTHERN PLAINS INTO OZARK PLATEAU... OUTFLOW BOUNDARY WITH SLOWLY WEAKENING CONVECTION EXTENDED FROM CENTRAL AR WWD INTO CENTRAL/NWRN OK. A RELATIVELY STRONG MESO-HIGH ASSOCIATED WAS PUSHING THIS BOUNDARY SWD...AND SHOULD EXTEND FROM SRN AR WWD INTO NERN TX...AND THEN NWWD INTO SWRN OK/TX PANHANDLE BEFORE STALLING LATER THIS MORNING. WEAK CONVERGENCE ALONG THIS BOUNDARY MAY PROVIDE SUFFICIENT LIFT FOR RENEWED CONVECTIVE DEVELOPMENT LATE THIS AFTERNOON. ALTHOUGH INSTABILITY WILL NOT BE PARTICULARLY STRONG...DUE TO WARM MID-LEVEL TEMPERATURES...DEEP MIXED BOUNDARY LAYER...WITH 30-40 DEGREE SURFACE TEMPERATURE/DEW POINT SPREADS...MAY SUPPORT A LOCALIZED THREAT FOR SHORT LIVED MICRO BURSTS. ...TN/UPPER OH VALLEYS EWD INTO THE CAROLINAS... STRONG HEATING OF THE MOIST BOUNDARY LAYER WILL RESULT IN MLCAPE VALUES TO RANGE FROM 2000 TO 3000 J/KG. DESPITE THE LACK OF DYNAMICAL FORCING...A WEAK CAP SHOULD ALLOW SCATTERED THUNDERSTORM CLUSTERS TO DEVELOP. WEAK WINDS/SHEAR WILL RESULT IN DISORGANIZED STORMS...BUT STRONG TEMPERATURE DIFFERENTIAL BETWEEN THE HEAVY RAIN CORES AND HOT ENVIRONMENTAL CONDITIONS MAY RESULT IN ISOLATED SHORT LIVED MICROBURSTS. ..IMY.. 07/14/2006  From swody1 at goshenarc.org Mon Jul 17 00:57:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 16 Jul 2006 20:57:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170055 SWODY1 SPC AC 170053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT SUN JUL 16 2006 VALID 170100Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF ERN SD EWD TO THE UPPER GRTLKS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE DESERT SW... ...ERN SD EWD TO THE UPPER GRTLKS... LATEST SFC MESOANALYSIS PLACES A WEAK TROUGH FROM NEAR LAKE OF THE WOODS SWWD INTO CNTRL SD...ASSOCIATED WITH A SUBTROPICAL IMPULSE MIGRATING EWD THROUGH SD. A STRONGER NRN STREAM IMPULSE WAS DIGGING SEWD THROUGH THE CANADIAN PRAIRIES WITH A MORE SIGNIFICANT COLD FRONT ARCING FROM LAKE WINNIPEG SWWD INTO NCNTRL MT. HIGH-BASED TSTMS ROOTED INTO THE VERY UNSTABLE BOUNDARY LAYER ACROSS THE MN ARROWHEAD EARLY THIS EVE...PRESUMABLY WHERE LOW-LEVEL WARM ADVECTION WAS MAXIMIZED JUST NE OF THE PRIMARY THERMAL RIDGE OVER THE PLAINS. THESE TSTMS HAVE WEAKENED...BUT NEW STORMS MAY FORM OVERNIGHT...BOTH ALONG THE LLJ AXIS FROM LK SUP EWD INTO UPPER MI...NWRN-SRN ONT...AND AHEAD OF THE NRN STREAM JETLET ACROSS NRN MN. SUFFICIENT EFFECTIVE SHEAR WILL EXIST FOR SUPERCELLS...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE. A SECONDARY AREA OF TSTM DEVELOPMENT APPEARS PROBABLE ACROSS EXTREME ERN SD EWD INTO CNTRL/SRN MN THIS EVE AHEAD OF THE SUBTROPICAL DISTURBANCE. THESE STORMS...INITIALLY HIGH-BASED...COULD TAP INTO MORE UNSTABLE PARCELS EMANATING FROM THE HIGHER THETA-E AXIS ACROSS THE CORN BELT. IF THIS OCCURS...WHETHER STORMS REMAIN ELEVATED OR BECOME SFC BASED...LARGE HAIL AND/OR DAMAGING WINDS WILL BE RISKS. THESE STORMS COULD MOVE INTO PARTS OF THE UPPER MS VLY REGION BY 12Z MON. ...DESERT SW... ENHANCED LOW/MID-TROPOSPHERIC ELY FLOW DOMINATED THE DIURNAL CYCLE AGAIN OVER SERN AZ...CONTRIBUTING TO DOWNSLOPE AND SUBSEQUENT DRYING OF THE BOUNDARY LAYER...LIMITING INSTABILITY. FARTHER NW...TSTMS HAVE BEEN WIDELY SCATTERED AND FAVORING AREAS THAT DID NOT SEE ROBUST CONVECTION YESTERDAY. MOST UNSTABLE AIR MASS THIS EVENING REMAINS OVER THE LOWER DESERTS FROM WRN PIMA COUNTY NWD TO MOHAVE COUNTY. TSTMS THAT DEVELOP/MOVE WITHIN/INTO THIS INSTABILITY AXIS WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS/HAIL. BUT...OVERALL...THE SEVERE THREATS SEEM TO BE LOWER THAN PREVIOUSLY ANTICIPATED. ..RACY.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 05:56:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 01:56:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170553 SWODY1 SPC AC 170551 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1251 AM CDT MON JUL 17 2006 VALID 171200Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... ...SYNOPSIS... UPPER RIDGE AXIS IS EXPECTED TO REMAIN STRONG ACROSS THE MAJORITY OF THE COUNTRY ON MON. A TWO STREAM FLOW WILL EXIST ALONG THE NRN PERIPHERY OF THE RIDGE WITH THE STRONGEST NRN STREAM SKIRTING THE GRTLKS AND NRN NEW ENGLAND REGIONS...WITH A WEAKER SUBTROPICAL STREAM ARCING FROM THE NRN ROCKIES TO THE MIDWEST. A COUPLE OF SHORTWAVE TROUGHS WILL BE THE IMPETUS FOR POSSIBLE SEVERE TSTMS MON AFTN/NIGHT. NRN STREAM IMPULSE...NOW OVER SRN MANITOBA...WILL DIG SEWD THROUGH THE GRTLKS REGION BY MON AFTN...THEN APPROACH NRN NEW ENGLAND BY 12Z TUE. MEANWHILE...A SUBTROPICAL WAVE OVER THE UPPER MS VLY AT THE START OF THE PERIOD WILL MOVE ESEWD INTO THE CORN BELT MON AFTN...THEN THE MIDWEST BY EARLY TUE. ...UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... HIGH-BASED TSTMS NOW DEVELOPING ACROSS PORTIONS OF ERN SD AND MN ARE LIKELY TO SPREAD EWD INTO THE UPPER MS VLY BY 12Z...AND SHOULD WEAKEN MON MORNING AS THE LLJ RELAXES. THE PRIMARY SEVERE THREAT WILL DEVELOP MON AFTN/EVE. PLUME OF HOT TEMPERATURES WILL BE MAINTAINED ALONG/AHEAD OF THE SEWD MOVING COLD FRONT ASSOCIATED WITH THE NRN STREAM IMPULSE. GIVEN BOUNDARY LAYER DEW POINTS BEING MAINTAINED AOA 65 DEG F...MLCAPES WILL RANGE FROM 2000-4000 J PER KG. AS STRONGER MID-LEVEL HEIGHT FALLS/COOLING SPREAD SEWD ACROSS LAKE SUPERIOR...TSTM WILL INITIATE ALONG THE COLD FRONT FROM UPPER MI AND BACKBUILD SWWD INTO PARTS OF WI BY MID-AFTN MON. VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS...BUT EVOLUTION INTO LINE SEGMENTS WILL BE FAVORED. GIVEN UNIDIRECTIONAL WLY FLOW...BOW ECHOES ARE POSSIBLE WITH DAMAGING WINDS AND LARGE HAIL. THIS ACTIVITY WILL MOVE ESEWD INTO SRN ONT AND PARTS OF LWR MI DURING MON EVE AND PROBABLY WEAKEN OVERNIGHT AS THE PRIMARY UPPER FORCING MOVES EWD INTO CANADA. MEANWHILE...A SEPARATE CLUSTER OF TSTMS IS LIKELY TO FORM ACROSS PARTS OF IA MON AFTN. CINH WILL BE GREATER THAN FARTHER NE...BUT VERY HOT TEMPERATURES AND PRESENCE OF A SUB-TROPICAL DISTURBANCE MOVING THROUGH THE REGION SHOULD BE FAVORABLE FOR SCT TSTMS. GIVEN MAGNITUDE OF LAPSE RATES/INSTABILITY...STORMS WILL GROW RAPIDLY AND SUPERCELLS WILL BE POSSIBLE WITH LARGE HAIL. ACTIVITY COULD EVOLVE INTO AN MCS DURING THE EVENING...AND ACCELERATE EWD INTO SRN WI AND NRN IL OVERNIGHT WITH A DAMAGING WIND THREAT. ...SWRN DESERTS... UPPER LEVEL LOW WILL CONTINUE TO ROTATE WWD THROUGH SONORA/SRN AZ INTO SRN CA MON INTO TUE. ENHANCED ELY FLOW ALONG NRN PERIPHERY OF THIS FEATURE WILL CONTINUE ACROSS THE SWRN DESERTS. TSTMS WILL LIKELY FORM OVER THE RIM AND ACROSS THE LWR DESERTS TOWARD THE LWR CO RVR VLY MON AFTN/EVE. ISOLD DAMAGING WINDS WILL BE POSSIBLE. SERN AZ MAY AGAIN SEE AFTN DRYING OF THE BOUNDARY LAYER IF THE LOW-LEVEL AMBIENT FLOW REGIME OVERCOMES THE DIURNAL CYCLE. THIS WOULD TEND TO REDUCE THE OVERALL CONVECTIVE/SEVERE THREATS OVER THAT AREA. ...GULF COASTAL REGION... WEAK E-W ORIENTED UPPER SHEAR AXIS WILL REMAIN ALONG THE GULF COASTAL REGION ON MON. GIVEN A WEAK LOW-LEVEL CONVERGENCE ZONE...PRESENCE OF VERY HIGH PRECIPITABLE WATER VALUES AND HOT CONDITIONS...TSTM WILL BE LIKELY FROM PARTS OF ERN TX EWD TO NRN FL. WEAK TROPOSPHERIC FLOW WILL FAVOR MULTICELL STORM CLUSTERS THAT WILL LIKELY PULSE TO NEAR SEVERE LEVELS WITH DAMAGING WINDS THE PRIMARY SEVERE RISK. ACTIVITY WILL BE LARGELY TIED TO THE DIURNAL CYCLE AND WEAKEN DURING THE MID-EVENING. ..RACY/JEWELL.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 12:45:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 08:45:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 171243 SWODY1 SPC AC 171241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT MON JUL 17 2006 VALID 171300Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL GREAT LAKES SWWD INTO NRN IL AND ERN IA.... ...SYNOPSIS... UPPER RIDGE AXIS WILL REMAIN ANCHORED E-W ACROSS MOST OF THE CONUS ...THOUGH A STRONG SHORTWAVE TROUGH WILL MOVE ESEWD THROUGH SRN ONTARIO AND LOWER HEIGHTS ACROSS THE GREAT LAKES REGION DURING THE PERIOD. AN ASSOCIATED COLD FRONT...CURRENTLY MOVING THROUGH THE WRN GREAT LAKES...IS FORECAST TO EXTEND FROM NRN LOWER MI SWWD INTO SOUTH CENTRAL IA/NORTH CENTRAL KS BY LATE AFTERNOON. ...CENTRAL UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... STRONG CAPPING INVERSION WILL ONCE AGAIN PLAY HAVOC WITH TIMING AND LOCATION OF SEVERE STORMS TODAY...THOUGH COOLING ALOFT AND LARGE SCALE ASCENT SHOULD WEAKEN THE INVERSION ENOUGH FOR SURFACE BASED STORMS TO DEVELOP ALONG THE FRONT THIS AFTERNOON. THIS MORNING...MOSTLY NON-SEVERE ELEVATED CONVECTION IS EXPECTED ACROSS SERN MN/NWRN IA/U.P./WI...AHEAD OF A WEAK SUBTROPICAL SHORTWAVE TROUGH LOCATED IN CENTRAL MN. THERE IS A SMALL CHANCE THAT STORMS EAST OF LAKE SUPERIOR COULD BACKBUILD INTO THE ERN U.P. THIS MORNING AS THE CAP SLOWLY WEAKENS. INTENSE SURFACE BASED STORMS ARE MOST LIKELY TO DEVELOP MID/LATE AFTERNOON FROM NRN/CENTRAL LOWER MI SWWD INTO SRN WI...AND EVENTUALLY ERN IA AS THE STORMS BACKBUILD SWWD ALONG THE FRONT. ONCE SURFACE BASED STORMS DEVELOP...THEY WILL BE LOCATED WITHIN A VERY UNSTABLE AIRMASS WITH MLCAPES FROM 3000 TO 4000 J/KG. THE DEGREE OF INSTABILITY COMBINED WITH 40 KT DEEP LAYER SHEAR WILL BE FAVORABLE FOR SUPERCELLS. THE AMOUNT OF INSTABILITY SHOULD SUPPORT VERY LARGE HAIL...ESPECIALLY THE FIRST FEW HOURS AFTER INITIATION SINCE THE STORMS ARE EXPECTED TO BE CELLULAR. THEREAFTER...THE OUTFLOWS SHOULD MERGE INTO A SEWD MOVING LINE ALONG THE FRONT... WITH WIND DAMAGE BECOMING THE MAIN SEVERE THREAT AS THE STORMS MOVE INTO SRN LOWER MI AND NRN IL DURING THE EVENING. HOWEVER... THE LOW LEVEL JET AND MASS CONVERGENCE ARE FORECAST TO WEAKEN OVERNIGHT...SO THE STORMS SHOULD WEAKEN AS THEY MOVE SEWD INTO NRN INDIANA/CENTRAL IL OVERNIGHT. ...SWRN DESERTS... WEAK UPPER LEVEL CIRCULATION SHOULD CONTINUE MOVING SLOWLY WWD INTO SRN CA TODAY. THE MOIST AND UNSTABLE ENVIRONMENT PLUS THE LIFT ASSOCIATED WITH THE UPPER LOW SHOULD ONCE AGAIN INITIATE AFTERNOON THUNDERSTORMS OVER THE RIM. WITH 35 KT ELY MID LEVEL WINDS...THESE STORMS SHOULD MOVE WWD INTO THE LWR DESERTS TOWARD THE LOWER CO RIVER VALLEY DURING THE LATE AFTERNOON/EVENING HOURS. ALTHOUGH ISOLATED WIND DAMAGE IS POSSIBLE...THE WIND THREAT MAY BE LOWER THAN THE PAST FEW DAYS DUE TO THE STRONG CONVECTIVE OVERTURNING. ...GULF COASTAL REGION... A DIFFUSE SURFACE TROUGH AND WEAK CAPPING SHOULD RESULT IN SCATTERED THUNDERSTORMS TO DEVELOP DURING THE AFTERNOON...ROUGHLY WITHIN 100 NM OF THE GULF COAST FROM SERN TX TO THE FL PANHANDLE. A HOT AND MOIST BOUNDARY LAYER WILL FAVOR MULTICELL CLUSTERS WITH A POTENTIAL FOR BRIEF STRONG DOWNBURSTS. THE STORMS SHOULD DIE OUT QUICKLY AFTER 01Z WITH LOSS OF DAYTIME HEATING. ..IMY/JEWELL.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 16:31:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 12:31:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 171629 SWODY1 SPC AC 171627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT MON JUL 17 2006 VALID 171630Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM ERN IA TO MI.... ...MS VALLEY/GREAT LAKES AREA THIS AFTERNOON INTO TONIGHT... A MID LEVEL SHORTWAVE TROUGH OVER ONTARIO...WITH A LOBE EXTENDING SWD OVER MN/WI...WILL MOVE GENERALLY EWD OVER THE GREAT LAKES THROUGH EARLY TUESDAY. AN ASSOCIATED SURFACE COLD FRONT WILL CONTINUE SEWD ACROSS IA/WI/NRN IL/MI BY LATE TONIGHT. THIS SURFACE FRONT WILL PROVIDE A FOCUS FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON INTO TONIGHT ACROSS THE SLIGHT RISK AREA. SURFACE ANALYSES AND 12Z SOUNDINGS SHOW LOWER 70S BOUNDARY LAYER DEWPOINTS BENEATH A PLUME OF 8-9 C/KM MID LEVEL LAPSE RATES WITHIN THE WARM SECTOR. WHEN COMBINED WITH AFTERNOON TEMPERATURES IN THE 90S...STRONG INSTABILITY /MLCAPE VALUES FROM 3000-4000 J/KG/ WILL BE PRESENT FROM ERN IA NEWD INTO LOWER MI BY MID-LATE AFTERNOON. THE ELEVATED MIXED LAYER SHOULD CONFINE THUNDERSTORM DEVELOPMENT TO THE IMMEDIATE FRONTAL ZONE BY 21-00Z WHERE DEEP MIXING/ASCENT WILL REMOVE CONVECTIVE INHIBITION. THE STRONG INSTABILITY AND MODEST DEEP LAYER VERTICAL SHEAR MAY SUPPORT A FEW SUPERCELLS AND/OR BOWING SEGMENTS WITHIN A THE BAND OF STORMS ALONG THE FRONT. LARGE HAIL...SOME OF WHICH COULD BE QUITE LARGE GIVEN THE VERY STEEP MID LEVEL LAPSE RATES...AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE THREATS THIS AFTERNOON INTO EARLY TONIGHT. ...CENTRAL/SRN AZ...SE CA...EXTREME SRN NV THIS AFTERNOON/EVENING... A PRONOUNCED WAVE IN THE ELYS IS NOW MOVING OVER NRN BAJA. RELATIVELY RICH LOW-MID LEVEL MOISTURE HAS OVERSPREAD MUCH OF CENTRAL/SRN AZ AND SE CA IN ASSOCIATION WITH THIS WAVE...AND SEVERAL CLUSTERS OF THUNDERSTORMS WILL LIKELY FORM AGAIN TODAY OVER RIM IN AZ AND OTHER MORE LOCALIZED TERRAIN FEATURES. AFTERNOON MLCAPE VALUES OF 1000-1500 J/KG AND 25-30 KT ELY/ESELY MID LEVEL FLOW SHOULD SUPPORT A FEW ORGANIZED MULTICELL CLUSTERS THAT WILL MOVE WWD OFF THE HIGHER TERRAIN THIS AFTERNOON/EVENING. THE STRONGEST STORMS COULD PRODUCE ISOLATED DAMAGING OUTFLOW WINDS AND MARGINALLY SEVERE HAIL. ...GULF COAST THIS AFTERNOON... A REMNANT MID LEVEL CYCLONIC CIRCULATION HAS DRIFTED SSWWD OVER SRN MS/SE LA...AND A WEAK NW-SE ORIENTED SURFACE TROUGH/FRONT PERSISTS FROM NRN LA INTO SRN MS/AL. MODIFIED MORNING SOUNDINGS SHOW THE POTENTIAL FOR STRONG INSTABILITY THIS AFTERNOON AND MINIMAL CONVECTIVE INHIBITION WITH SURFACE TEMPERATURES IN THE LOWER 90S. THE STRONGEST STORMS MAY PRODUCE ISOLATED DAMAGING DOWNBURST WINDS GIVEN THE STRONG INSTABILITY...SOME DRY AIR ALOFT...AND STEEP LOW-LEVEL LAPSE RATES THIS AFTERNOON. ..THOMPSON/CROSBIE.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 20:05:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 16:05:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 172002 SWODY1 SPC AC 172000 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0300 PM CDT MON JUL 17 2006 VALID 172000Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES INTO THE MIDDLE MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN TX INTO WRN/SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF CENTRAL/SRN AZ... ...GREAT LAKES/MIDDLE MS VALLEY... WATER VAPOR IMAGERY SHOWS A STRONG SHORT WAVE TROUGH MOVING EWD ACROSS ONTARIO/LAKE SUPERIOR...ACCOMPANIED BY A 50-60 KT MID LEVEL JET STREAK OVER LAKE SUPERIOR AND NRN WI/UPR MI. SURFACE COLD FRONT IS CURRENTLY EXTENDING FROM ERN LAKE SUPERIOR ACROSS CENTRAL WI INTO SWRN IA...AND THIS BOUNDARY IS EXPECTED TO REACH A ST LAWRENCE VALLEY/CENTRAL INDIANA/CENTRAL MO LINE BY 18/12Z. VERY MOIST AND WARM AIR MASS IS LOCATED AHEAD OF THE FRONT WITH SURFACE TEMPERATURES IN THE 90S AND DEW POINTS IN THE 70S. 12Z SOUNDINGS INDICATED ELEVATED MIXED LAYER/STEEP MID LEVEL LAPSE RATES EXTENDED EWD INTO THE GREAT LAKES REGION...ENHANCING POTENTIAL INSTABILITY /MLCAPE OF 3000-4000 J/KG/ BUT ALSO LIMITING CONVECTIVE DEVELOPMENT IN THE WARM SECTOR AHEAD OF THE COLD FRONT. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS HAVE FORMED FROM NRN LOWER MI SWWD INTO EAST CENTRAL WI AND NERN IA...AND A WEAKENING CAP IMMEDIATELY ALONG/AHEAD OF THE FRONT SHOULD PERMIT ADDITIONAL STORMS TO DEVELOP THIS AFTERNOON AND EVENING. PRESENCE OF VERY UNSTABLE ENVIRONMENT COUPLED WITH 30-40 KT DEEP LAYER VERTICAL SHEAR WILL SUPPORT ADDITIONAL SEVERE STORMS TO DEVELOP THROUGH THE EVENING HOURS...WITH STRONGEST UPDRAFTS CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS. STRONG/SEVERE CONVECTION MOVING FROM WI INTO LOWER MI AND TOWARD THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS AS STRONG DYNAMIC FORCING ASSOCIATED WITH THE SHORT WAVE OVERSPREADS THE AREA FROM THE WEST AND PROVIDES FAVORABLE FORCING FOR LARGE SCALE ASCENT. A FEW SEVERE STORMS MAY ALSO DEVELOP SWWD ALONG THE FRONT INTO PARTS OF CENTRAL/SWRN IA LATER THIS AFTERNOON WHERE VISIBLE IMAGERY SHOWS CU FIELD BECOMING ENHANCED...WITH THIS ACTIVITY GRADUALLY SPREADING SEWD INTO NRN MO. THIS ACTIVITY IS LIKELY TO WEAKEN AFTER SUNSET. ...ARKLATEX INTO SRN LA... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL CYCLONIC CIRCULATION MOVING SLOWLY SWD ACROSS SERN LA...WITH STRONG MID/UPPER LEVEL DRYING SPREADING SWD ACROSS THE REGION. THERMODYNAMIC PROFILES ARE CHARACTERIZED BY INCREASING TEMPERATURE/DEW POINT SPREADS AS A LOW LEVEL INVERTED-V SOUNDING STRUCTURE DEVELOPS IN THE LOWEST 1-2 KM...WITH THETA-E DECREASING RAPIDLY ABOVE THE VERY MOIST PBL. 20 KT NELY WINDS ALOFT WILL FAVOR SWWD PROPAGATION OF STORMS WITH POTENTIAL FOR WET MICROBURSTS TO DEVELOP. SEE MESOSCALE DISCUSSION 1537 FOR MORE DETAILS. ...CENTRAL/SRN AZ... VISIBLE IMAGERY SHOWS REMNANTS OF A MESOSCALE CONVECTIVE VORTEX MOVING NWWD OVER SERN AZ. ENVIRONMENT IN ADVANCE OF THIS FEATURE IS MODERATELY MOIST WITH SURFACE DEW POINTS IN THE UPPER 50S/LOWER 60S...AND STRONG INSOLATION SHOULD ALLOW TEMPERATURES TO CONTINUE WARMING THIS AFTERNOON. CONVECTION IS EXPECTED TO GRADUALLY INCREASE OVER THE HIGHER TERRAIN OF SERN AZ...WITH STORMS SPREADING NWWD INTO THE LOWER DESERTS OF SOUTH CENTRAL AND SWRN AZ WITHIN BAND OF 20-25 KT ESELY FLOW IN THE 700-500 MB LAYER. STEEP LOW LEVEL LAPSE RATES WITHIN WELL-MIXED BOUNDARY LAYER EXTENDING UP TO 750-700 MB AND ASSOCIATED LARGE VALUES OF DOWNDRAFT CAPE INDICATE POTENTIAL FOR WET MICROBURSTS PRODUCING DAMAGING WIND GUSTS AND REDUCED VISIBILITIES IN BLOWING DUST. ..WEISS.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 23:24:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 19:24:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 172322 SWODY1 SPC AC 172320 DAY 1 CONVECTIVE OUTLOOK AMEND 1 NWS STORM PREDICTION CENTER NORMAN OK 0620 PM CDT MON JUL 17 2006 VALID 172000Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES INTO THE MIDDLE MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN TX INTO WRN/SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SWRN DESERTS/LWR CO RVR VLY... AMENDED FOR SLGT RISK ACROSS THE LAS VEGAS AREA ***AMENDED PORTION*** ...LWR CO RVR VLY AND THE SWRN DESERTS... STRONGEST TSTMS HAVE DEVELOPED ALONG THE HIGH COUNTRY ACROSS NWRN AZ NWD INTO AREAS N-E OF KLAS. THESE STORMS WILL PROPAGATE WWD TOWARD THE LWR CO RVR VLY AREA...INCLUDING THE LAS VEGAS VLY LATER THIS EVENING WITH RISKS OF DAMAGING WINDS AND PERHAPS HAIL. FARTHER S...ACTIVITY HAS BEEN SUPPRESSED THIS AFTN. BUT...AN MCV CONTINUES TO MOVE WNWWD THROUGH PIMA COUNTY AND MAY BE THE IMPETUS FOR INCREASING TSTMS LATER THIS EVENING. THESE STORMS WILL ALSO HAVE A RISK OF DAMAGING WINDS. ***REMAINDER UNCHANGED*** ...GREAT LAKES/MIDDLE MS VALLEY... WATER VAPOR IMAGERY SHOWS A STRONG SHORT WAVE TROUGH MOVING EWD ACROSS ONTARIO/LAKE SUPERIOR...ACCOMPANIED BY A 50-60 KT MID LEVEL JET STREAK OVER LAKE SUPERIOR AND NRN WI/UPR MI. SURFACE COLD FRONT IS CURRENTLY EXTENDING FROM ERN LAKE SUPERIOR ACROSS CENTRAL WI INTO SWRN IA...AND THIS BOUNDARY IS EXPECTED TO REACH A ST LAWRENCE VALLEY/CENTRAL INDIANA/CENTRAL MO LINE BY 18/12Z. VERY MOIST AND WARM AIR MASS IS LOCATED AHEAD OF THE FRONT WITH SURFACE TEMPERATURES IN THE 90S AND DEW POINTS IN THE 70S. 12Z SOUNDINGS INDICATED ELEVATED MIXED LAYER/STEEP MID LEVEL LAPSE RATES EXTENDED EWD INTO THE GREAT LAKES REGION...ENHANCING POTENTIAL INSTABILITY /MLCAPE OF 3000-4000 J/KG/ BUT ALSO LIMITING CONVECTIVE DEVELOPMENT IN THE WARM SECTOR AHEAD OF THE COLD FRONT. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS HAVE FORMED FROM NRN LOWER MI SWWD INTO EAST CENTRAL WI AND NERN IA...AND A WEAKENING CAP IMMEDIATELY ALONG/AHEAD OF THE FRONT SHOULD PERMIT ADDITIONAL STORMS TO DEVELOP THIS AFTERNOON AND EVENING. PRESENCE OF VERY UNSTABLE ENVIRONMENT COUPLED WITH 30-40 KT DEEP LAYER VERTICAL SHEAR WILL SUPPORT ADDITIONAL SEVERE STORMS TO DEVELOP THROUGH THE EVENING HOURS...WITH STRONGEST UPDRAFTS CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS. STRONG/SEVERE CONVECTION MOVING FROM WI INTO LOWER MI AND TOWARD THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS AS STRONG DYNAMIC FORCING ASSOCIATED WITH THE SHORT WAVE OVERSPREADS THE AREA FROM THE WEST AND PROVIDES FAVORABLE FORCING FOR LARGE SCALE ASCENT. A FEW SEVERE STORMS MAY ALSO DEVELOP SWWD ALONG THE FRONT INTO PARTS OF CENTRAL/SWRN IA LATER THIS AFTERNOON WHERE VISIBLE IMAGERY SHOWS CU FIELD BECOMING ENHANCED...WITH THIS ACTIVITY GRADUALLY SPREADING SEWD INTO NRN MO. THIS ACTIVITY IS LIKELY TO WEAKEN AFTER SUNSET. ...ARKLATEX INTO SRN LA... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL CYCLONIC CIRCULATION MOVING SLOWLY SWD ACROSS SERN LA...WITH STRONG MID/UPPER LEVEL DRYING SPREADING SWD ACROSS THE REGION. THERMODYNAMIC PROFILES ARE CHARACTERIZED BY INCREASING TEMPERATURE/DEW POINT SPREADS AS A LOW LEVEL INVERTED-V SOUNDING STRUCTURE DEVELOPS IN THE LOWEST 1-2 KM...WITH THETA-E DECREASING RAPIDLY ABOVE THE VERY MOIST PBL. 20 KT NELY WINDS ALOFT WILL FAVOR SWWD PROPAGATION OF STORMS WITH POTENTIAL FOR WET MICROBURSTS TO DEVELOP. SEE MESOSCALE DISCUSSION 1537 FOR MORE DETAILS. ..JPR/WEISS.. 07/17/2006  From swody1 at goshenarc.org Tue Jul 18 00:53:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 20:53:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 180050 SWODY1 SPC AC 180048 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 PM CDT MON JUL 17 2006 VALID 180100Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MIDWEST TO THE CNTRL GRTLKS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SWRN DESERTS... ...MIDWEST TO THE CNTRL GRTLKS... PRIMARY UPPER SHORTWAVE TROUGH HAS BEGUN TO TRANSLATE INTO SERN CANADA THIS EVENING. COOLING ALOFT AND WEAK HEIGHT FALLS ALONG SRN PERIPHERY OF THIS IMPULSE WERE SUFFICIENT TO FOCUS A BAND OF TSTMS ALONG/AHEAD OF THE COLD FRONT ACROSS CNTRL WI TO NRN/CNTRL LWR MI THIS AFTN/EVE. TSTMS CONTINUE TO MOVE ESEWD WHILE BACKBUILDING SWWD INTO THE EXTREME INSTABILITY AXIS CHARACTERIZED BY MLCAPE TO 4500 J PER KG. VERTICAL SHEAR REMAINS SUFFICIENT FOR SUPERCELLS...THOUGH THE RELATIVELY DRY MID-LEVELS CONTINUES TO BE FAVORABLE FOR COLD POOL GENERATION. MODEST UNIDIRECTIONAL WLY FLOW REGIME WILL ENCOURAGE CELLS TO BOW AND DAMAGING WINDS /A FEW WITH WIND GUSTS AOA 65 KT/ WILL REMAIN POSSIBLE ALONG WITH LARGE HAIL /ISOLD HAILSTONES AOA 2 INCHES IN DIAMETER/. FARTHER SW...THE IA TSTM CLUSTER CONTINUES TO EVOLVE ALONG THE MS RVR WITHIN WEAK DIFFLUENT FLOW REGIME. SWRN FLANK OF THE MCS HAS A SUBSTANTIAL COLD POOL AND TSTMS APPEAR TO BE BACKBUILDING S AND SW INTO NERN MO. NRN FLANK HAS SHOWN A TENDENCY TO DEVELOP/MOVE MORE EWD AND MAY EVENTUALLY DEVELOP/LINK UP WITH THE ACTIVITY BACKBUILDING SWWD ALONG THE COLD FRONT FROM WI. UPSHOT WILL PROBABLY BE AN EXPANDING AREA OF TSTMS FROM NWRN-NRN IL. VERY STEEP LAPSE RATES ALOFT WILL LIKELY FOSTER VERY LARGE HAIL PRODUCTION ALONG WITH DAMAGING WIND GUSTS. ACTIVITY SHOULD GRADUALLY WEAKEN LATER TONIGHT AS IT SINKS SEWD INTO ECNTRL MO-CNTRL IL-NRN IND AND LAKE ERIE OWING TO STABILIZING BOUNDARY LAYER AND WEAKENING LOW-LEVEL FLOW REGIME. ...SWRN DESERTS... 00Z RAOB FROM TUCSON REVEALS A RELATIVELY STABLE SOUNDING WITH DOWNSLOPE ELY FLOW. MORE UNSTABLE AIR MASS RESIDES THROUGH THE LWR CO RVR VLY. EARLIER TSTM DEVELOPMENT ALONG THE HIGHER TERRAIN OF NWRN AZ CONTINUES TO PROPAGATE WWD TOWARD THE INSTABILITY AXIS AND WILL LIKELY CONTINUE TO THE CO RVR AND POSSIBLY PARTS OF THE LAS VEGAS VLY LATER THIS EVENING. FARTHER S...MCV CONTINUES TO ROTATE WWD THROUGH CNTRL PIMA COUNTY. TSTMS MAY YET DEVELOP OR EXPAND ALONG/AHEAD OF THE VORT TRACK THROUGH SWRN AZ THROUGH THE EVENING. ANY TSTM ACROSS THE SWRN DESERTS WILL BE CAPABLE OF DAMAGING WINDS/DUST STORMS. ...NRN NY INTO NWRN NEW ENGLAND... THERE WILL BE A LOW PROBABILITY OF TSTMS WITH ISOLD DAMAGING WIND GUSTS APPROACHING NRN NY INTO NWRN NEW ENGLAND VERY LATE TONIGHT. UPSTREAM TSTM CLUSTERS CONTINUE TO EVOLVE OVER SRN ONT AND QUE. STRONGER FORCING ALOFT AND ATTENDANT SWLY LLJ WILL TRANSLATE NEWD THROUGH SERN CANADA OVERNIGHT. THERE IS SOME CONCERN THAT STRONGER BOW ECHOES MAY BE MAINTAINED OVERNIGHT AND APPROACH THE INTERNATIONAL BORDER FROM ME TO NRN NY STATE BY 12Z. ..RACY.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 06:09:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 02:09:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 180605 SWODY1 SPC AC 180603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT TUE JUL 18 2006 VALID 181200Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NERN STATES WWD INTO THE OH VLY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN SD INTO WRN MN... ...SYNOPSIS... PRIMARY WLYS WILL REMAIN ALONG THE CANADIAN BORDER THROUGH TUE. TWO SHORTWAVE TROUGHS WILL MOVE EWD WITHIN THE FLOW. THE LEAD TROUGH... CURRENTLY MOVING ACROSS THE GRTLKS REGION WILL MOVE ACROSS QUE AND ACROSS THE ST. LAWRENCE VLY AND NRN NEW ENGLAND TUE AFTN. THE UPSTREAM IMPULSE WILL MOVE ACROSS THE SRN CANADIAN PRAIRIES. IN THE LWR LVLS...A COLD FRONT WILL MOVE SEWD ACROSS NEW ENGLAND AND THE OH VLY. WRN END OF THE FRONT WILL BEGIN TO LIFT NWD DURING TUE NIGHT AS A LOW DEVELOPS EWD FROM THE HIGH PLAINS INTO PARTS OF THE DAKS. MEANWHILE...A SECONDARY COLD FRONT WILL BEGIN TO SWING EWD INTO THE DAKS BY LATE TUE AFTN. ...NERN STATES/MID-UPPER OH VLY... A MOIST BOUNDARY LAYER...CHARACTERIZED BY DEW POINTS IN THE UPPER 60S TO LOWER 70S...WILL REMAIN IN PLACE ALONG/SOUTH OF THE COLD FRONT ON TUE. ATOP THIS MOISTURE...A PLUME OF STEEP H7-H5 LAPSE RATES OF 7-7.5 DEG C PER KM EMANATING FROM THE PLAINS WILL EXIST. THIS ELEVATED MIXED LAYER WILL LIKELY DELAY CONVECTIVE INITIATION UNTIL AFTN. BUT...COMBINATION OF STRONG HEATING...WEAK HEIGHT FALLS AND CONVERGENCE ALONG THE COLD FRONT/PRE-FRONTAL TROUGHS...CINH SHOULD ERODE SUFFICIENTLY FOR TSTMS INITIATION FROM ME SWWD INTO NRN OH BY MID-AFTN. THE STRONGER DEEP LAYER SHEAR WILL EXIST ALONG THE BASE OF THE H5 TROUGH ACROSS NY EWD INTO NEW ENGLAND WHERE 40-50 KTS OF FLOW SHOULD BE COMMON. WLY UNIDIRECTIONAL NATURE TO THE FLOW WILL BE SUFFICIENT FOR SUPERCELLS...BUT EVOLUTION INTO BOWING LINE SEGMENTS WILL LIKELY OCCUR QUICKLY...GIVING DAMAGING WIND GUSTS ALONG WITH LARGE HAIL. THERE ARE SOME UNCERTAINTIES REVOLVING AROUND FRONTAL TIMING AND ANTICIPATED COVERAGE OF THE STORMS. ONCE MORE CONFIDENCE IS GAINED...AN UPGRADE TO CATEGORICAL MODERATE RISK MAY BE NEEDED. FARTHER SW...VERTICAL SHEAR WILL BE MUCH WEAKER...BUT MAGNITUDE OF LAPSE RATES/HOT BOUNDARY LAYER WILL BE FAVORABLE FOR MICROBURSTS AND PERHAPS AN ISOLD SUPERCELL OR TWO WITH LARGE HAIL FROM PARTS OF PA WWD INTO OH. ...LWR OH VLY... REGION WILL REMAIN BENEATH DIFFLUENT UPPER FLOW REGIME THROUGH TUE. VERY UNSTABLE CONDITIONS WILL DEVELOP ACROSS THE LWR OH VLY OWING TO RICH BOUNDARY LAYER MOISTURE AND STEEP MID-LEVEL LAPSE RATES. REMNANT OUTFLOW BOUNDARIES/COLD FRONT WILL BE MOVING SWD THROUGH PARTS OF IND WWD INTO PARTS OF MO AND COULD BE IMPETUS FOR TSTMS BY LATE AFTN. MAIN LIMITING FACTORS FOR STORMS WILL BE THE WARM TEMPERATURES ALOFT. HOWEVER...GIVEN A STORM...LARGE HAIL AND DAMAGING WINDS WILL BE LIKELY. ...GULF COASTAL REGION... UPPER SHEAR AXIS WILL REMAIN ACROSS THE GULF COASTAL REGION ON TUE AND TSTMS SHOULD FORM IN ASSOCIATION WITH THIS FEATURE AGAIN TUE AFTN. SATL SHOWS A CONSIDERABLE AMOUNT OF DRY AIR ENTRAINING INTO THIS FEATURE ATOP RICH BOUNDARY LAYER MOISTURE. THIS SUGGESTS THAT ISOLD MICROBURSTS MAY OCCUR WITH THE STRONGER STORMS ANYWHERE ALONG THE GULF COAST. ...FOUR CORNERS REGION... TSTMS WILL LIKELY FORM BENEATH UPPER RIDGE AXIS...WITH HIGHEST PROBABILITIES ACROSS THE FOUR CORNERS REGION. TROPOSPHERIC FLOW WILL BE LIGHT AND PULSE MULTICELL CLUSTERS WILL BE THE MAIN CONVECTIVE MODE. TYPICALLY DRY SUB-CLOUD LAYER COULD CONTRIBUTE TO ISOLD STORMS PRODUCING DAMAGING WIND GUSTS. ...NRN PLAINS... A STRONG EML WILL CONTINUE FROM THE ROCKIES INTO THE PLAINS TUE. THIS SHOULD EFFECTIVELY CAP SFC BASED PARCELS. BUT...HIGH BASED CONVECTION IS APT TO INCREASE OFF THE HIGHER TERRAIN. AS THE WARM FRONT LIFTS NWD ACROSS THE LWR/MIDDLE MO RVR VLY DURING LATE AFTN/OVERNIGHT...MOISTURE ADVECTION WILL INCREASE ALONG AN ACCELERATING SLY LLJ BENEATH THE EML. AS A RESULT...SOME OF THE AFTN CONVECTION MAY EVOLVE INTO AN MCS OVERNIGHT ACROSS PARTS OF SD INTO MN...OR ALONG THE EDGE OF THE STRONGER CAP. EFFECTIVE SHEAR WILL BE INCREASING OVERNIGHT AND GIVEN MAGNITUDE OF LAPSE RATES/ELEVATED CAPE...A FEW STORMS MAY PRODUCE LARGE HAIL AND PERHAPS GUSTY WINDS. ..RACY/JEWELL.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 12:43:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 08:43:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 181240 SWODY1 SPC AC 181238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT TUE JUL 18 2006 VALID 181300Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND SWWD ACROSS THE OHIO VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN PLAINS... ...SYNOPSIS... LARGE UPPER RIDGE WILL DOMINATE THE WEATHER ACROSS MOST OF THE CONUS...WITH THE STRONGER MID LEVEL WINDS RESTRICTED TO THE NRN BORDER STATES. WITHIN THESE WESTERLIES...ONE SHORTWAVE TROUGH WILL MOVE FROM THE GREAT LAKES INTO NEW ENGLAND...WHILE A SECOND SYSTEM MOVES FROM OREGON INTO THE NRN ROCKIES. IN ASSOCIATION WITH THE LEAD TROUGH...A COLD FRONT WILL MOVE SEWD ACROSS NEW ENGLAND/OH VALLEY AND REMAIN QUASI-STATIONARY ACROSS THE MID MS VALLEY. THE WRN END OF THE FRONT WILL LIFT NWD FROM KS INTO NEB TONIGHT AS AN AREA OF LOW PRESSURE DEVELOPS ACROSS THE NRN PLAINS. ...NEW ENGLAND AND NY... ALTHOUGH ELEVATED STORMS ARE NOW MOVING THROUGH WRN ME... RELATIVELY WARM TEMPERATURES ALOFT ARE LIKELY TO INHIBIT SURFACE BASED CONVECTIVE DEVELOPMENT UNTIL LATE MORNING/EARLY AFTERNOON. THIS MEANS STRONGER CONVECTION IS MORE LIKELY LATER TODAY FROM CENTRAL ME SWWD INTO LOWER NY. ONCE SURFACE BASED STORMS DEVELOP ...THEY WILL BE ABLE TO INGEST STRONG INSTABILITY WITH MLCAPES FROM 2000-3000 J/KG. THIS INSTABILITY AND 40-50 KT DEEP LAYER SHEAR WILL SUPPORT SUPERCELLS. HOWEVER...THE DEEP UNDIRECTIONAL WLY WINDS THROUGHOUT THE TROPOSPHERE ARE LIKELY TO EVOLVE STORMS INTO LINES/BOWS...WITH WIND DAMAGE THE PRIMARY THREAT. ALTHOUGH UNCERTAINTY EXISTS ON WHEN/WHERE STORMS ARE MOST FAVORED...A HIGHER WIND POTENTIAL IS EXPECTED ACROSS THE ERN PORTIONS OF NEW ENGLAND SINCE THE FRONT/STORMS SHOULD PUSH THROUGH THESE AREAS DURING THE TIME OF MAX HEATING/INSTABILITY. THE SEVERE THREAT SHOULD END BY MID EVENING AS THE STORMS MOVE OFFSHORE. ...PA/OH AND MID MS VALLEYS... COLD FRONT/OUTFLOW BOUNDARY EXTEND FROM WRN NY TO A WEAK WAVE LOCATED IN NORTH CENTRAL IL...AND THEN SWWD INTO NRN MO. ELEVATED CONVECTION HAD DEVELOPED OVER CENTRAL IL THIS MORNING WITHIN INSTABILITY AXIS AND ZONE OF WEAK WARM ADVECTION...BUT STORMS SHOULD WEAKEN THIS MORNING AS WARM ADVECTION CEASES. MORE INTENSE CONVECTION IS EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE WEAK COLD FRONT/REMNANT OUTFLOW BOUNDARIES. STRONG DAYTIME HEATING... STEEP MID LEVEL LAPSE RATES AND A MOIST BOUNDARY LAYER WILL RESULT IN MLCAPES TO RANGE FROM 2000 J/KG OVER PA/OH TO NEARLY 4000 J/KG ACROSS SRN IL/EAST CENTRAL MO. WARM MID LEVEL TEMPERATURES SHOULD LIMIT WRN EXTENT OF CONVECTIVE DEVELOPMENT TO ERN MO/IL...BUT MOST INTENSE CONVECTION SHOULD BE LOCATED ON THE ERN EDGE OF THIS CAP. ONCE STORMS DEVELOP...THE AMOUNT OF INSTABILITY AND 25-30 KT DEEP LAYER SHEAR WILL FAVOR MULTICELL STORM CLUSTERS WITH HAIL AND WIND DAMAGE. ...NRN PLAINS... TIMING AND LOCATION OF SEVERE CONVECTION IS QUESTIONABLE DUE TO SUBTLE DIFFERENCES IN THE CURRENT AND PAST ETA/GFS MODEL RUNS. HOWEVER...MODELS GENERALLY SUPPORT A LOW LEVEL JET/WARM ADVECTION DEVELOPING OVERNIGHT ACROSS THE ERN DAKOTAS/WRN MN AS A SHORTWAVE TROUGH MOVES INTO THE NRN ROCKIES. THE BOUNDARY LAYER WILL BE STRONGLY CAPPED...BUT STEEP LAPSE RATES ABOVE THE INVERSION WILL BE FAVORABLE FOR ELEVATED CONVECTION TO DEVELOP AFTER 03-06Z. EFFECTIVE SHEAR WILL BE INCREASING OVERNIGHT AND THE STEEP LAPSE RATES/ELEVATED CAPE MAY SUPPORT STORMS WITH SEVERE HAIL. ...GULF COASTAL REGION... NUMEROUS THUNDERSTORMS WERE LOCATED OFF THE LA COAST THIS MORNING IN ASSOCIATION WITH A WEAK SHEAR AXIS ALOFT. STORMS SHOULD DEVELOP INLAND LATER THIS MORNING AND AFTERNOON AND ALTHOUGH THE DEEP LAYER SHEAR IS WEAK...STRONG INSTABILITY AND HOT TEMPERATURES WILL SUPPORT SHORT-LIVED MICRO BURSTS. ...FOUR CORNERS REGION... MID/HIGH LEVEL MOISTURE TRAPPED UNDER UPPER RIDGE WILL LIKELY RESULT IN NUMEROUS DIURNAL THUNDERSTORMS. ENVIRONMENTAL WINDS/ SHEAR WILL BE WEAK...BUT A RELATIVELY DRY AND DEEP BOUNDARY LAYER MAY SUPPORT A FEW STRONG WINDS GUSTS. ..IMY/JEWELL.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 16:42:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 12:42:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 181639 SWODY1 SPC AC 181638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT TUE JUL 18 2006 VALID 181630Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FROM CENTRAL MO ACROSS THE OH VALLEY INTO NEW ENGLAND.... ...OH VALLEY TO NEW ENGLAND TODAY... A MID LEVEL TROUGH EXTENDING FROM NRN IL TO THE SAINT LAWRENCE VALLEY...ALONG WITH AN ASSOCIATED SURFACE COLD FRONT AND PRE-FRONTAL TROUGH...WILL MOVE EWD OVER THE OH VALLEY AND NEW ENGLAND BY TONIGHT. STRONG SURFACE HEATING NEAR AND E OF THE PRE-FRONTAL TROUGH...BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S TO LOWER 70S...AND STEEP LOW-MID LEVEL LAPSE RATES WILL RESULT IN MLCAPE VALUES OF 1500-2500 J/KG. EXPECT THUNDERSTORM DEVELOPMENT TO OCCUR FROM MIDDAY INTO EARLY AFTERNOON AS SURFACE HEATING/MIXING REMOVES CONVECTIVE INHIBITION FROM CENTRAL PA NEWD ACROSS SRN NEW ENGLAND INTO SRN/ERN MAINE. ROUGHLY 40 KT WSWLY FLOW IN THE 700-500 MB LAYER WILL COMBINE WITH THE STEEP LOW-LEVEL LAPSE RATES AND LARGE DCAPE VALUES /GREATER THAN 1000 J/KG/ TO SUPPORT A THREAT FOR DAMAGING WINDS WITH THE STRONGER CELLS/BOWING SEGMENTS. LARGE HAIL WILL ALSO BE POSSIBLE GIVEN THE STEEP MID LEVEL LAPSE RATES LARGE MLCAPE. ...MO/IL THIS AFTERNOON/EVENING... THE SURFACE COLD FRONT EXTENDS WWD INTO IL/MO/KS...WITH A WEAK SURFACE LOW JUST N OF STL. BOUNDARY LAYER DEWPOINTS REMAIN IN THE MID 70S ALONG AND S OF THE FRONT...THOUGH EARLY STORMS ACROSS SRN IL HAVE TEMPORARILY DELAYED SURFACE HEATING. STILL...CLEARING OF THE CLOUDS WILL ALLOW AFTERNOON TEMPERATURES TO WARM INTO THE 90S FROM CENTRAL MO TO CENTRAL IL...WHICH WILL RESULT IN MLCAPE VALUES OF 2500-4000 J/KG. THOUGH LOW-LEVEL SHEAR IS RELATIVELY WEAK OVER THIS AREA...30 KT NWLY MID LEVEL FLOW COULD RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR ORGANIZED MULTICELL CLUSTERS OR STORMS WITH SOME SUPERCELL STRUCTURES. THE STRONG INSTABILITY WILL SUPPORT A THREAT FOR DAMAGING OUTFLOW WINDS AND LARGE HAIL LATER THIS AFTERNOON/EVENING. ...NRN PLAINS... WATER VAPOR IMAGERY FEATURES MID LEVEL SPEED MAXIMA MOVING EASTWARD FROM ERN MT INTO THE DAKOTAS AT MIDDAY. IN THE WAKE OF ONGOING ELEVATED TSTMS ACROSS SRN ND/NRN SD...STRONG INSOLATION/HEATING WILL LEAD TO A MODESTLY UNSTABLE/WEAKLY CAPPED BOUNDARY LAYER THIS AFTERNOON. ISOLATED STRONG STORMS CAPABLE OF STRONG WIND GUSTS/SOME HAIL WILL LIKELY DEVELOP ALONG THE LEE TROUGH/ADVANCING COLD FRONT THIS AFTERNOON/EARLY EVENING. LATER TONIGHT...NUMERICAL MODEL GUIDANCE GENERALLY SUPPORTS THE DEVELOPMENT OF A 40 KT LOW LEVEL JET/WARM ADVECTION REGIME OVERNIGHT ACROSS THE ERN DAKOTAS/WRN MN. STEEP LAPSE RATES ABOVE A CAPPED BOUNDARY LAYER WILL BE FAVORABLE FOR AT LEAST ISOLATED ELEVATED CONVECTION TO DEVELOP AFTER 03-06Z. GIVEN SUFFICIENT CLOUD BEARING SHEAR AND PRESENCE OF STEEP LAPSE RATES/ELEVATED CAPE...THE STRONGEST STORMS MAY BE CAPABLE OF SEVERE HAIL OVERNIGHT. ...GULF COAST REGION... NUMEROUS THUNDERSTORMS CONTINUE AT MIDDAY ALONG THE TX UPPER COASTAL PLAIN IN ASSOCIATION WITH A WESTWARD MOVING WEAK SHEAR AXIS ALOFT. GIVEN DIURNAL HEATING...STORMS SHOULD DEVELOP INLAND THROUGH THE AFTERNOON...NAMELY FROM THE MIDDLE TX COAST/SOUTHEAST TX INTO THE CENTRAL GULF COAST STATES AND FL PENINSULA. ALTHOUGH THE DEEP LAYER SHEAR IS WEAK...STRONG INSTABILITY AND HOT TEMPERATURES WILL SUPPORT THE POTENTIAL FOR SHORT-LIVED MICROBURSTS CAPABLE OF STRONG WIND GUSTS. ...FOUR CORNERS REGION... MID/HIGH LEVEL MOISTURE REMAINS BENEATH UNDER UPPER RIDGE...WITH NUMEROUS DIURNAL THUNDERSTORMS LIKELY THIS AFTERNOON. AMBIENT VERTICAL SHEAR WILL BE WEAK...LIMITING SEVERE STORM ORGANIZATION/LONGEVITY. NEVERTHELESS...A RELATIVELY DRY AND DEEPLY MIXED BOUNDARY LAYER WILL SUPPORT A FEW STRONG WINDS GUSTS/PERHAPS HAIL. ..THOMPSON/GUYER.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 20:03:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 16:03:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 182000 SWODY1 SPC AC 181958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT TUE JUL 18 2006 VALID 182000Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND ACROSS THE MIDDLE ATLANTIC STATES INTO THE MIDDLE MS VALLEY... ...NERN STATES INTO THE MIDDLE MS VALLEY... UPPER TROUGH FROM QUEBEC SWWD ACROSS THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE MOVING EWD THROUGH TONIGHT. ERN PART OF THE ASSOCIATED SURFACE COLD FRONT CURRENTLY FROM SRN ME SWWD INTO CENTRAL PA AND CENTRAL IL WILL MOVE SEWD ACROSS THE MID ATLANTIC STATES...WHILE WRN PORTION OF THE FRONT MOVES MORE SLOWLY ACROSS THE OH VALLEY. A VERY WARM/MOIST LOW LEVEL AIR MASS IS PRESENT ALONG/AHEAD OF THE FRONT WITH SURFACE TEMPERATURES GENERALLY IN THE UPPER 80S/LOWER 90S AND DEW POINTS IN THE UPPER 60S TO LOWER 70S...WITH HIGHER DEW POINTS IN THE MID/UPPER 70S NOTED OVER PARTS OF IL/ERN MO. THE HIGH THETA-E AIR MASS IS CONTRIBUTING TO A MODERATELY TO VERY UNSTABLE ENVIRONMENT WITH MLCAPE RANGING FROM 1500-2500 J/KG FROM SRN NEW ENGLAND ACROSS THE MIDDLE ATLANTIC STATES INTO THE OHIO VALLEY TO 3000-4000 J/KG IN THE MIDDLE MS VALLEY. STRONG/SEVERE THUNDERSTORMS HAVE DEVELOPED OVER NRN NEW ENGLAND...WITH ADDITIONAL CLUSTERS OVER PA...ERN WV...AND WRN OH. VISIBLE SATELLITE IMAGERY INDICATES ENHANCED CU/TCU ALONG THE FRONT CENTRAL PA INTO EAST CENTRAL OH SUGGESTING NEW THUNDERSTORMS MAY DEVELOP SOON ACROSS THIS AREA. ALTHOUGH STRONGER DEEP LAYER SHEAR OF 30-40 KT EXISTS FROM NY INTO NEW ENGLAND...MODERATE SHEAR OF 20-30 KT ACROSS THE DELMARVA/PA/OH AREA SHOULD BE SUFFICIENT TO ENHANCE CONVECTIVE ORGANIZATION AND SUPPORT A FEW SEVERE STORMS CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND LARGE HAIL INTO THE EVENING HOURS. FARTHER WEST...VISIBLE IMAGERY SHOWS A DEVELOPING CU FIELD NEAR A SURFACE LOW OVER SOUTH CENTRAL IL. CONTINUED HEATING COUPLED WITH HIGH SURFACE DEW POINTS AND DRYING ALOFT ARE COMBINING TO PRODUCE VERY UNSTABLE CONDITIONS. HOWEVER...THE DRYING/SUBSIDENCE ALOFT ALSO APPEARS TO BE INHIBITING DEEP CONVECTIVE INITIATION ATTM. AS THE CAP CONTINUES TO WEAKEN...A FEW PARCELS MAY REACH THE LFC WITH SUBSEQUENT RAPID THUNDERSTORM DEVELOPMENT POSSIBLE. NWLY MID LEVEL WINDS OF 25 KT WILL PROVIDE SUFFICIENT DEEP LAYER SHEAR FOR SEVERE THUNDERSTORMS TO DEVELOP. VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE WITH ANY PERSISTENT UPDRAFTS THAT CAN DEVELOP. ...GULF COAST REGION... SCATTERED CONVECTION HAS DEVELOPED FROM AL AND EXTREME WRN GA SWWD ACROSS MS/LA INTO SERN TX. 20-30 DEG F TEMPERATURE/DEW POINT SPREADS AT THE SURFACE COUPLED WITH STEEP LOW LEVEL LAPSE RATES AND PRONOUNCED DRYING IN THE MID/UPPER LEVELS INDICATES POTENTIAL FOR A FEW WET MICROBURSTS TO OCCUR. ...PARTS OF CA/WRN NV... VISIBLE IMAGERY SHOWS A WELL-DEFINED MESOSCALE CONVECTIVE VORTEX MOVING NWWD INTO CENTRAL CA. THIS MAY ENHANCE THUNDERSTORM DEVELOPMENT ACROSS THIS REGION LATER THIS AFTERNOON AND EVENING. ...NRN PLAINS... WEAK ELEVATED CONVECTION HAS MOVED EWD ACROSS NRN SD...WITH CLEAR SKIES AND STRONG INSOLATION OCCURRING IN ITS WAKE OVER THE NRN PLAINS. AN ELEVATED MOISTURE RETURN WILL INCREASE TONIGHT IN RESPONSE TO A STRENGTHENING SOUTHERLY LOW LEVEL JET. THIS SUGGESTS POTENTIAL FOR ELEVATED THUNDERSTORMS TO DEVELOP DURING THE OVERNIGHT HOURS OVER PARTS OF THE DAKOTAS WHICH MAY BE CAPABLE OF PRODUCING HAIL WITH STRONGER STORMS. CONVECTIVE COVERAGE APPEARS TO BE TOO LIMITED TO WARRANT A SLIGHT RISK AREA. ..WEISS.. 07/18/2006  From swody1 at goshenarc.org Wed Jul 19 01:09:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 21:09:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190106 SWODY1 SPC AC 190104 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0804 PM CDT TUE JUL 18 2006 VALID 190100Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SRN NEW ENGLAND SWWD TO PARTS OF THE MID-ATLANTIC REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LWR OH VLY WWD INTO SERN MO... ...SRN NEW ENGLAND SWD TO DELMARVA... LATEST MESOANALYSIS PLACES THE STRONGEST INSTABILITY AXIS /MLCAPES 1500-2500 J PER KG/ EXTENDING FROM SOUTH OF THE MASS TURNPIKE SWWD INTO NEW YORK CITY AND THEN INTO THE DELMARVA REGION. THE SEABREEZE HAS PENETRATED INLAND ACROSS EXTREME SERN NEW ENGLAND WHERE 00Z CHH SOUNDING EXHIBITED A SHALLOW MARINE LAYER. MAJORITY OF THE TSTMS HAVE EVOLVED FROM SWRN CT SWWD INTO MD EARLY THIS EVE WHERE THE BOUNDARY LAYER WAS THE HOTTEST/MOST UNSTABLE TODAY. THOUGH THE STRONGEST DEEP LAYER SHEAR WAS RELEGATED TO AREAS NORTH OF NEW YORK CITY...THE VERY STEEP LAPSE RATES AND WLY...LARGELY UNIDIRECTIONAL FLOW HAS BEEN FAVORABLE FOR TSTM LINE SEGMENTS TO BOW GIVING DAMAGING WIND GUSTS. THROUGH THE REMAINDER OF THE EVENING...STRONGER STORMS SHOULD CONTINUE EWD THROUGH PARTS OF EXTREME SERN PA...NJ...DE AND LWR MD. TSTMS MAY TEND TO WEAKEN ACROSS SRN NEW ENGLAND/LONG ISLAND AS THE STORMS ENCOUNTER THE MARINE LAYER. DAMAGING WINDS AND LARGE HAIL WILL BE THE PRIMARY SEVERE THREATS. SEVERE WEATHER PROBABILITIES WILL DECREASE LATER THIS EVENING. ...LWR OH VLY WWD INTO SERN MO... A COUPLE STRONG-SEVERE TSTM CLUSTERS CONTINUE TO PROPAGATE SWWD ACROSS PORTIONS OF THE LWR OH VLY AND SERN MO BENEATH DIFFLUENT UPPER FLOW REGIME. THE IND STORMS APPEAR TO HAVE DEVELOPED ALONG THE SYNOPTIC COLD FRONT EARLY IN THE AFTN AND ARE THRIVING ON VERY UNSTABLE PARCELS...MLCAPE TO 2500 J PER KG. FARTHER SW...TSTMS THAT DEVELOPED SOUTH OF KSTL PROBABLY FORMED ALONG RESIDUAL OUTFLOW BOUNDARIES FROM EARLY DAY ACTIVITY. THESE STORMS ARE ALSO EMBEDDED WITHIN A VERY UNSTABLE ENVIRONMENT WITH MLCAPE TO 3500 J PER KG. ACTIVITY WILL GRADUALLY WEAKEN AS CINH INCREASES BY LATE EVE. UNTIL THEN...VERTICAL SHEAR OF 40-45 KTS AND MAGNITUDE OF LAPSE RATES/INSTABILITY SUGGEST THAT LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE. AN ISOLD TORNADO IS ALSO NOT OUT OF THE QUESTION. ...SWRN DESERTS... CONVECTIVE COVERAGE HAS INCREASED OVER THE PAST SEVERAL DAYS ACROSS THE SWRN DESERTS...PARTICULARLY OVER THE SCNTRL AZ DESERTS. THIS MAY BE DUE TO SLIGHTLY MORE FAVORABLE UPPER AIR DIVERGENCE ALONG THE BACKSIDE OF DEPARTING UPPER LOW. THE STRONGEST TSTM CLUSTER WILL LIKELY CONTINUE NEAR/S OF THE KPHX METRO AREA SWD TO CNTRL/WRN PIMA COUNTY THROUGH THE EVE HOURS. HAIL AND GUSTY WINDS/DUST STORMS WILL ACCOMPANY THE STORMS. ...NRN PLAINS... ELEVATED MOISTURE RETURN WILL INCREASE TONIGHT IN RESPONSE TO A STRENGTHENING SOUTHERLY LOW LEVEL JET ACROSS PORTIONS OF THE NRN PLAINS. THIS SUGGESTS THE POTENTIAL FOR ELEVATED THUNDERSTORMS TO DEVELOP DURING THE OVERNIGHT HOURS OVER PARTS OF THE DAKS WHICH MAY BE CAPABLE OF PRODUCING HAIL OR GUSTY WINDS WITH STRONGER STORMS. ANTICIPATED CONVECTIVE COVERAGE APPEARS TO BE TOO LIMITED TO WARRANT A SLGT RISK AREA. ..RACY.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 05:55:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 01:55:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190552 SWODY1 SPC AC 190551 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1251 AM CDT WED JUL 19 2006 VALID 191200Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS CENTRAL AND SOUTHEASTERN MN...CENTRAL AND SOUTHERN WI AND A SMALL PART OF NORTHEAST IA... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN PARTS OF THE NRN PLAINS EWD ACROSS THE UPPER MS VLY TO THE CNTRL GRTLKS... ...SYNOPSIS... STRONGER WLYS WILL REMAIN ALONG THE NRN TIER OF THE COUNTRY ON WED AS THE UPPER RIDGE AXIS CONTINUES ACROSS THE CNTRL PARTS OF THE PLAINS AND ROCKIES. A SHORTWAVE TROUGH...EMBEDDED WITHIN A WEAKER SUBTROPICAL JET S OF THE PRIMARY WLYS OVER THE NRN ROCKIES...WILL PROGRESS ESEWD REACHING THE UPPER MS VLY/UPPER GRTLKS BY THE END OF THE PERIOD. AT THE SFC...AN ASSOCIATED COLD FRONT WILL MOVE EWD ACROSS THE NRN PLAINS AND UPPER MS VLY...REACHING A WRN LAKE SUPERIOR/SWRN MN/NRN NEB LINE BY 20/00Z...AND CONTINUING TO ERN LAKE SUPERIOR/SWRN WI/SWRN IA BY THE END OF THE PERIOD. MEANWHILE...A WARM FRONT WILL LIFT RAPIDLY NWD ACROSS THE UPPER MS VLY DURING THE MORNING WITH A VERY MOIST WARM SECTOR DEVELOPING BY AFTN. ...UPPER MS VLY/CNTRL GRTLKS... TUE EVENING UPPER AIR ANALYSIS SHOWS A STRONG WARM PLUME OF AIR STREAMING EWD FROM THE CNTRL HIGH PLAINS TOWARD THE MO RVR VLY WITH H7 TEMPERATURES IN EXCESS OF 16 DEG C AT KLBF. THIS ELEVATED MIXED LAYER /EML/ WILL SPREAD INTO AT LEAST IA BY WED AFTN. TO THE N OF THIS CAP...CONSIDERABLE ELEVATED CONVECTION IS EXPECTED TO BE ONGOING WED MORNING FROM THE DAKOTAS EWD INTO NWRN MN. STORMS MAY ALREADY BE PRODUCING LARGE HAIL AT THAT TIME. THIS ACTIVITY MAY PERSIST/DEVELOP EWD ACROSS NRN MN AND INTO THE UPPER GRTLKS LATER IN THE DAY WITH RISKS FOR DAMAGING WINDS AS WELL. ATTENTION WILL THEN TURN TO A RATHER ACTIVE AFTN AND EVENING FROM PARTS OF CNTRL/SRN MN INTO THE CNTRL GRTLKS. BOUNDARY LAYER MOISTURE IS EXPECTED TO RAPIDLY RETURN NWD BENEATH THE EML AND BY AFTN UPPER 60S TO MID 70S F/MID-TEENS C SFC/H85 DEW POINTS WILL BE COMMON ACROSS THE UPPER MS VLY. STRONG HEATING WILL CONTRIBUTE TO A VERY TO EXTREMELY UNSTABLE AIR MASS. STRONGEST CAP WILL HOLD ACROSS SWRN MN AND IA...BUT AS LARGE SCALE ASCENT ASSOCIATED WITH THE TROUGH SPREADS EWD...THE CAP SHOULD WEAKEN ACROSS CNTRL/SRN MN BY MID-AFTN. AS A RESULT...TSTMS SHOULD DEVELOP ALONG/AHEAD OF THE COLD FRONT AND EWD ALONG THE WARM FRONT MID-LATE AFTN FROM CNTRL MN EWD INTO PARTS OF WI. VERTICAL SHEAR PROFILES WILL BECOME STRONGER THROUGH THE LATE AFTN AS A 50-70 KT H5 JET MOVES ACROSS THE REGION...BOOSTING 0-6KM VALUES IN THE 60-70 KT RANGE. GIVEN THE MAGNITUDE OF LAPSE RATES...INITIAL TSTMS WILL GROW INTO SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WINDS. HODOGRAPHS BECOME QUITE LARGE VCNTY THE WARM FRONT FROM CNTRL/SRN MN ACROSS SWRN WI AS A SWLY LLJ OF 40 KTS BECOMES JUXTAPOSED WITH THE 70 KT WNWLY H5 JET DURING THE LATE AFTN. LOW LCLS AND STRONG LOW-LEVEL SHEAR WILL BE FAVORABLE FOR A FEW TORNADOES WITH THE INITIAL SUPERCELLS...PRIMARILY ALONG THE WARM FRONT. EVOLUTION INTO A FORWARD PROPAGATING BOW ECHO/DERECHO APPEARS LIKELY DURING THE EVENING AS THE LLJ VEERS WLY AND BECOMES ALIGNED WITH THE WNWLY 70 KT H5 JET. THIS WILL INCREASE THE DAMAGING WIND RISK INTO WI AND POSSIBLY AS FAR E AND S AS PARTS OF LWR MI AND NRN IND/IL BY 12Z THU. ADDITIONAL TSTMS WILL TEND TO BACKBUILD WWD INTO THE CAP ACROSS IA DURING THE OVERNIGHT WITH AN ATTENDANT RISK OF LARGE HAIL. ...CNTRL-SRN APPALACHIANS... WEAK BOUNDARIES WILL BE PRESENT ACROSS PARTS OF THE CNTRL-SRN APPALACHIANS WED. STRONG HEATING...AMPLE BOUNDARY LAYER MOISTURE AND WEAK UPSLOPE COMPONENT WILL CONTRIBUTE TO TSTMS DEVELOPING ESPECIALLY ALONG THE ERN SLOPES OF THE MOUNTAINS. MULTICELL STORM CLUSTERS MAY APPROACH/BRIEFLY EXCEED SEVERE LIMITS WITH DAMAGING WINDS THE PRIMARY THREAT THREAT. ...GULF COASTAL STATES... DIURNAL TSTMS...ENHANCED BY LOCAL CONVERGENCE FROM OUTFLOW BOUNDARIES/SEA BREEZE...WILL BE LIKELY ACROSS MOST OF THE GULF COASTAL REGION WED AFTN. THETA-E PROFILES WILL DECREASE RAPIDLY WITH HEIGHT AND SUGGESTS THAT ISOLD MICROBURSTS MAY ACCOMPANY THE PULSE MULTICELL STORM CLUSTERS. ...SWRN DESERTS... 00Z WED H5 CHART SUGGESTS THAT THE MID-TROPOSPHERE SHOULD WARM A DEGREE OR TWO OVER TUE READINGS ACROSS THE SWRN DESERTS. BUT...BOUNDARY LAYER MOISTURE MAY BE HIGHER THAN PREVIOUS DAYS OWING TO RECENT SLOW MOVING TSTMS. AS A RESULT...ANY TSTM THAT CAN MANAGE TO FORM MAY PRODUCE ISOLD DAMAGING WIND GUSTS. CONVECTIVE COVERAGE WILL BE HIGHLY MODULATED BY THE MAGNITUDE OF CLOUD DEBRIS THAT REMAINS OVER THE REGION FROM TUE EVE/OVERNIGHT TSTMS. ..RACY/TAYLOR.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 12:38:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 08:38:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191235 SWODY1 SPC AC 191234 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 AM CDT WED JUL 19 2006 VALID 191300Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF SERN MN...NERN IA AND SWRN WI... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MS RIVER VALLEY EWD TO THE GREAT LAKES... ...SYNOPSIS... WESTERLIES WILL REMAIN ACROSS THE NRN FOURTH OF THE COUNTRY...WHILE A LARGE UPPER RIDGE CONTINUES ITS HOLD OVER THE REST OF THE NATION. THE MAJOR FEATURE FOR SEVERE CONVECTION WILL BE A SHORTWAVE TROUGH...ASSOCIATED 60-70 KT MID LEVEL JET MAX AND COLD FRONT MOVING FROM THE DAKOTAS EWD INTO THE WESTERN GREAT LAKES DURING THIS PERIOD. A WARM FRONT ACROSS THE MO RIVER VALLEY WILL SHIFT NWD INTO SRN MN/WI THIS AFTERNOON. ...UPPER MS VLY/CNTRL GRTLKS... BAND OF ELEVATED THUNDERSTORMS IN WRN MN SHOULD SPREAD E/SEWD THIS MORNING AS THE LOW LEVEL JET VEERS. MUCAPES 2000+ J/KG AND STEEP LAPSE RATES INDICATE SEVERE HAIL IS POSSIBLE...BUT WARM MID LEVEL TEMPERATURES SHOULD LIMIT THE THREAT. EXPECT THE CLOUDS/PCPN FROM THIS COMPLEX WILL REINFORCE WARM FRONT ACROSS SRN MN THIS AFTERNOON. VERY WARM TEMPERATURES ALOFT...700 MB TEMPERATURES NEAR 16 DEG...INDICATE A STOUT CAP WILL ALSO BE IN PLACE. HOWEVER...THE COMBINATION OF LARGE SCALE LIFTING FROM TROUGH/JET MAX AND CONVERGENCE SHOULD AID RENEWED THUNDERSTORM DEVELOPMENT NEAR COLD FRONT/BOUNDARY INTERSECTION BETWEEN 19-22Z. ONCE STORMS FORM...THE AIR MASS WILL BE EXTREMELY UNSTABLE...MLCAPE VALUES IN EXCESS OF 4000 J/KG...AND WITH DEEP LAYER SHEAR NEAR 60 KT...RAPID DEVELOPMENT OF SUPERCELLS IS EXPECTED. THE BOUNDARY LAYER SHOULD BE QUITE MOIST NEAR THE WARM FRONT AND STRONGLY CURVED HODOGRAPHS IN THE LOWER 1 KM INDICATE A POTENTIAL FOR TORNADOES...ALONG WITH VERY LARGE HAIL. HOWEVER...THE STORMS SHOULD GENERATE STRONG OUTFLOWS THAT MERGE AND EVOLVE INTO A FORWARD PROPAGATING BOW ECHO/DERECHO AS THE LLJ BECOMES WLY AND ALIGNS WITH THE STRONG WINDS ALOFT. THE RESULTING COLD POOL SHOULD ALSO HELP DEVELOP A REAR INFLOW JET WITH WIDESPREAD DAMAGING WINDS POSSIBLE AS THE SYSTEM MOVES ESEWD ACROSS SERN MN/NERN IA/SWRN WI. THE LINEAR COMPLEX MAY CONTINUE MOVING SEWD OVERNIGHT INTO NRN IL AND LOWER MI...BUT THE STABILIZING BOUNDARY LAYER SHOULD DECREASE THE WIND THREAT. INTENSE HEATING AND FRONTAL CONVERGENCE MAY BE SUFFICIENT TO LIFT CAP FOR STORMS TO INITIATE ACROSS EXTREME SERN SD/NWRN IA AND NERN NEB BETWEEN 21-03Z. ANY STORMS THAT DEVELOP IN THIS DEEPLY MIXED BOUNDARY LAYER LIKELY WOULD PRODUCE STRONG/SEVERE WINDS. STORMS THAT DEVELOP SHOULD WEAKEN QUICKLY AFTER SUNSET AS THE CAP BECOMES REESTABLISHED. ...CNTRAL AND SRN APPALACHIANS... WEAK FRONT/BOUNDARY COMBINED WITH STRONG HEATING OF A MOIST BOUNDARY LAYER ACROSS THE CENTRAL/SRN APPALACHIANS SHOULD RESULT IN AFTERNOON THUNDERSTORM DEVELOPMENT. ENVIRONMENTAL WINDS WILL BE WEAK...BUT MODERATE INSTABILITY MAY SUPPORT A FEW DAMAGING WIND EVENTS. ...GULF COASTAL STATES... DIURNAL THUNDERSTORMS WILL ONCE AGAIN BE LIKELY ACROSS THE GULF COASTAL STATES WITH ISOLATED BRIEF WET MICROBURSTS POSSIBLE. ...SWRN DESERTS... WIDESPREAD CLOUDS AND A FEW THUNDERSTORMS WERE STILL OCCURRING ACROSS AZ THIS MORNING. STRONG HEATING OF THE RELATIVELY MOIST ENVIRONMENT SHOULD RESULT IN STORMS TO REDEVELOP THIS AFTERNOON. THE CONVECTIVE OVERTURNING OF STORMS THE PAST FEW DAYS AND WEAK WINDS ALOFT INDICATE THE THREAT FOR MORE THAN ISOLATED STRONG WIND GUSTS IS LIMITED. ..IMY/TAYLOR.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 16:31:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 12:31:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191628 SWODY1 SPC AC 191626 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1126 AM CDT WED JUL 19 2006 VALID 191630Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS NRN IA...SRN WI...AND NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO TONIGHT ACROSS MOST OF THE UPPER MS VALLEY AND PARTS OF MI... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS THE LOWER MS VALLEY... ...IA/MN/WI/IL THIS AFTERNOON/EVENING... A MID LEVEL SHORTWAVE TROUGH OVER THE NRN HIGH PLAINS WILL AMPLIFY SOME AND MOVE ESEWD TO THE UPPER MS VALLEY BY TONIGHT...WHILE AN ASSOCIATED SURFACE COLD FRONT MOVES SEWD FROM THE ERN DAKOTAS TO NW WI/CENTRAL IA/SRN NEB. THE SURFACE PATTERN IS COMPLICATED BY AN ONGOING MCS ACROSS SE MN/SW WI/NE IA. THIS CONVECTION DEVELOPED IN ASSOCIATION WITH LOW-LEVEL WAA AND A MID LEVEL SPEED MAX OVER NERN SD THIS MORNING. GIVEN THE WELL-DEVELOPED COLD POOL/BOW ECHO...MERGING CLUSTERS...AND A DESTABILIZING BOUNDARY LAYER IN ADVANCE OF THE STORMS...THE THREAT FOR DAMAGING WINDS APPEARS TO BE INCREASING ACROSS SRN WI AND NRN IL THIS AFTERNOON. OUTFLOW WITH THIS CONVECTION WILL ALSO MODULATE THE NWD PROGRESSION OF THE VERY UNSTABLE WARM SECTOR ACROSS IA/MN/WI. THE 12Z NAM REFLECTS THIS SCENARIO BY MAINTAINING THE ONGOING STORMS THROUGH THE DAY. HOWEVER...THIS MODEL APPEARS TO BE SEVERAL HOURS TOO SLOW WITH THE PROGRESSION OF THE MORNING STORMS. STRONG/EXTREME INSTABILITY IS EXPECTED ALONG THE TRAILING OUTFLOW BOUNDARY ACROSS IA...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. ADDITIONAL CONVECTION MAY FORM ALONG THE OUTFLOW ACROSS NW/N CENTRAL IA BY MID-LATE AFTERNOON...AND THEN MOVE ESEWD ACROSS THE REMAINDER OF IA AND INTO NRN IL TONIGHT. THE INITIAL STORMS MAY BE SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND A FEW TORNADOES WHERE LOW-LEVEL MOISTURE/SHEAR ARE ENHANCED ALONG THE BOUNDARY. THIS CONVECTION MAY GROW UPSCALE THIS EVENING INTO ANOTHER FORWARD PROPAGATING MCS WITH DAMAGING WINDS. ...LOWER MS VALLEY THIS AFTERNOON... WATER VAPOR IMAGERY SHOWS A WEAK MID LEVEL WAVE MOVING SWWD OVER NE MS. THE COMBINATION OF THIS WEAK MID LEVEL DISTURBANCE AND A DIFFUSE SFC TROUGH SHOULD HELP FOCUS THE DEVELOPMENT OF SEVERAL MULTICELL THUNDERSTORM CLUSTERS THIS AFTERNOON. MODIFYING THE 12Z JAN SOUNDING FOR AFTERNOON SURFACE TEMPERATURES IN THE LOW-MID 90S...MLCAPE WILL APPROACH 3000 J/KG AND LAPSE RATES FROM THE SURFACE TO NEAR 500 MB WILL BE NEAR 8 C/KM. THE 12Z SHV SOUNDING SHOWS A SIMILAR ENVIRONMENT...WITH SOMEWHAT STRONGER /30 KT/ NELY MID LEVEL FLOW AND MODEST DEEP LAYER SHEAR. A FEW DAMAGING DOWNBURSTS SHOULD BE THE MAIN THREAT...THOUGH ISOLATED LARGE HAIL WILL ALSO BE POSSIBLE WITH THE MOST INTENSE STORMS. ..THOMPSON/GUYER.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 20:10:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 16:10:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 192007 SWODY1 SPC AC 192005 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0305 PM CDT WED JUL 19 2006 VALID 192000Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS FROM NRN/ERN IA INTO NRN/CENTRAL IL... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK FROM THE UPPER MS VALLEY INTO THE UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER MS VALLEY/GULF COAST STATES... ...IA INTO NRN IL/NWRN INDIANA... ONGOING SEVERE MCS MOVING INTO NWRN IL IS EXPECTED TO CONTINUE MOVING SEWD INTO VERY WARM/MOIST ENVIRONMENT CHARACTERIZED BY SURFACE TEMPERATURES NEAR 90 AND DEW POINTS IN THE LOW/MID 70S. THIS IS RESULTING IN MLCAPE OF 2500-4000 J/KG...AND WITH CONTINUED AFTERNOON HEATING FURTHER DESTABILIZATION IS LIKELY. NWLY MID LEVEL WINDS OF 25-30 KT ACROSS THIS REGION IS CONTRIBUTING TO DEEP LAYER SHEAR OF 20-30 KT...WHICH IS SUFFICIENT TO MAINTAIN MESOSCALE ORGANIZATION OF THE CONVECTIVE SYSTEM. VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL BE LIKELY AS THE STORMS MOVE SEWD 35 KT ACROSS PARTS OF NRN/CENTRAL IL THIS AFTERNOON. THIS SYSTEM MAY CONTINUE SEWD INTO PARTS OF WEST CENTRAL/SWRN INDIANA THIS EVENING BEFORE SLOWLY WEAKENING AS IT MOVES INTO A REGION OF LESS FAVORABLE SHEAR. THE CURRENT MCS MOVING INTO NWRN IL HAS GENERATED A CONVECTIVE OUTFLOW BOUNDARY EXTENDING DIAGONALLY FROM SERN INTO NWRN IA AND EXTREME SERN SD...WHERE IT INTERSECTS A NE/SW ORIENTED COLD FRONT EXTENDING FROM NRN MN INTO CENTRAL NEB. ALTHOUGH VISIBLE IMAGERY AND RUC FORECAST SOUNDINGS INDICATE THE LOW LEVEL AIR MASS IS CURRENTLY CAPPED OVER THIS REGION...PERSISTENT CONVERGENCE AND DYNAMIC FORCING ALONG THE SRN EDGE OF A SHORT WAVE TROUGH MOVING TOWARD THE UPPER MS VALLEY ARE EXPECTED TO WEAKEN THE CAP SUFFICIENTLY FOR NEW CONVECTION TO DEVELOP LATER THIS AFTERNOON AND EVENING. VERY UNSTABLE CONDITIONS IMMEDIATELY SOUTH OF THE OUTFLOW BOUNDARY WITH MLCAPE EXCEEDING 4000 J/KG COUPLED WITH STRONG DEEP LAYER SHEAR/LOW LEVEL HELICITY INDICATE A FAVORABLE ENVIRONMENT FOR SUPERCELL THUNDERSTORMS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND GUSTS...AND A FEW TORNADOES /PRIMARILY ALONG AND JUST NORTH OF THE OUTFLOW BOUNDARY/. SEVERE CONVECTION IS FORECAST TO GROW UPSCALE INTO ANOTHER MCS LATER THIS EVENING AND TRACK ESEWD ALONG THE OUTFLOW BOUNDARY ACROSS THE MIDDLE MS VALLEY...WITH A CONTINUED THREAT FOR DAMAGING WIND GUSTS AND LARGE HAIL THROUGH THE OVERNIGHT HOURS. ...UPPER MS VALLEY INTO THE UPPER GREAT LAKES... ALTHOUGH THE CIRRUS CANOPY ASSOCIATED WITH THE IA/IL MCS EXTENDS NWD INTO SRN MN AND WI...LATEST VISIBLE IMAGERY SHOWS THINNING CLOUDS NEAR THE FRONT OVER EAST CENTRAL MN AND FAR NWRN WI. THIS MAY PERMIT ENHANCED HEATING AND AIR MASS DESTABILIZATION TO OCCUR...INCREASING THE POTENTIAL FOR ADDITIONAL STRONG/SEVERE STORMS TO DEVELOP ALONG/AHEAD OF THE ADVANCING COLD FRONT. A 50-60 KT MID LEVEL JET STREAK MOVING EWD ACROSS THIS AREA IN ASSOCIATION WITH THE SHORT WAVE TROUGH WILL INCREASE THE DYNAMIC FORCING FOR LARGE SCALE ASCENT AND CONTRIBUTE TO STRONG DEEP LAYER SHEAR. ALTHOUGH THE ENVIRONMENT IS LESS UNSTABLE COMPARED TO REGIONS FARTHER SOUTH...THERE WILL CONTINUE TO BE A THREAT FOR SEVERE THUNDERSTORMS SPREADING EWD ACROSS THIS REGION LATER THIS AFTERNOON INTO TONIGHT. ...UPPER TN VALLEY INTO THE GULF COAST REGION... SCATTERED THUNDERSTORMS HAVE DEVELOPED FROM NRN AL SWD INTO PARTS OF SWRN GA/SRN AL AND CENTRAL/SRN MS. THIS ACTIVITY IS WITHIN A THERMODYNAMIC ENVIRONMENT CHARACTERIZED BY AMPLE MOISTURE AND STEEP LAPSE RATES IN THE LOWEST 1-2 KM...WITH DRY AIR AND MODERATELY STEEP LAPSE RATES ALOFT. 20-25 KT NELY MID LEVEL WINDS WILL SUPPORT MODEST CONVECTIVE ORGANIZATION AND HELP MAINTAIN A THREAT FOR WET MICROBURSTS AND POSSIBLE HAIL WITH STRONGER CELLS. ...SRN APPALACHIANS NWD INTO PARTS OF VA... 18Z GSO AND RNK RAOBS EXHIBIT VERY STEEP LOW LEVEL LAPSE RATES AND LARGE SURFACE TEMPERATURE/DEW POINT SPREADS...WHICH WILL ENHANCE DOWNDRAFT STRENGTH. WEAK WINDS ALOFT AND MINIMAL VERTICAL SHEAR INDICATES LIKELIHOOD OF PULSE STORMS WITH ATTENDANT POTENTIAL FOR BRIEF MICROBURSTS. THIS CONVECTION SHOULD WEAKEN AFTER SUNSET. ..WEISS.. 07/19/2006  From swody1 at goshenarc.org Thu Jul 20 01:12:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 21:12:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200109 SWODY1 SPC AC 200108 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0808 PM CDT WED JUL 19 2006 VALID 200100Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER A PORTION OF THE UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MIDDLE AND UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER WRN LA THROUGH NERN TX... ...IA THROUGH SRN MN AND SRN THROUGH CNTRL WI... SURFACE OBSERVATIONS SHOW A COLD FRONT FROM A WEAK SURFACE LOW IN NERN NEB SWWD THROUGH CNTRL AND SWRN NEB. THIS BOUNDARY CONTINUES NEWD FROM THE LOW THROUGH CNTRL AND NRN MN. FARTHER S AN OUTFLOW BOUNDARY EXTENDS FROM SRN IL NWWD THROUGH NERN MO INTO W CNTRL AND NWRN IA WHERE IT INTERSECTS THE FRONT. THE ATMOSPHERE REMAINS EXTREMELY UNSTABLE IN THE PRE-FRONTAL WARM SECTOR ACROSS MUCH OF IA WITH MLCAPE FROM 4000 TO 5000 J/KG. WITH THE EXCEPTION OF HIGH BASED STORMS DEVELOPING WITHIN THE MORE DEEPLY MIXED PLUME JUST AHEAD OF THE FRONT ACROSS NEB...SURFACE BASED INITIATION HAS YET TO OCCUR. LACK OF CUMULUS WITHIN THE WARM SECTOR ACROSS IA SUGGESTS THE BOUNDARY LAYER IS STILL CAPPED AND THIS LENDS UNCERTAINTY AS TO WHEN THE STRONGER STORMS WILL INITIATE. THE MODERATE RISK THEREFORE REMAINS CONDITIONAL. SWLY LOW LEVEL JET WILL STRENGTHEN THIS EVENING OVER THE UPPER MS VALLEY AS NRN STREAM SHORTWAVE TROUGH MOVES ESEWD THROUGH SRN CANADA AND NRN MN. THIS SUGGEST THAT STORMS WILL INCREASE N OF THE OUTFLOW BOUNDARY WITHIN ZONE OF ISENTROPIC ASCENT FROM NRN IA INTO SERN MN AND SRN WI. MANY OF THESE STORMS MAY INITIALLY BE ELEVATED WITH A THREAT FOR MAINLY LARGE HAIL. HOWEVER...THE 00Z DAVENPORT RAOB SHOWS THE BOUNDARY LAYER TO BE SUFFICIENTLY DRY AND WARM TO SUPPORT A THREAT OF DAMAGING WIND...ESPECIALLY IF STORMS BEGIN TO CONGEAL INTO AN MCS AND IF STORMS CAN DEVELOP CLOSER TO THE STRONGER SURFACE BASED INSTABILITY ACROSS IA. GIVEN THE MAGNITUDE OF INSTABILITY AND SUFFICIENT VERTICAL SHEAR FOR SUPERCELL STRUCTURES...A FEW STORMS COULD PRODUCE VERY LARGE HAIL...ESPECIALLY IN THE MODERATE RISK AREA. TORNADO THREAT REMAINS CONDITIONAL UPON BEING ABLE TO INITIATE STORMS CLOSER TO THE OUTFLOW BOUNDARY ACROSS PARTS OF NRN AND CNTRL IA. ...SRN IL THROUGH E CNTRL AND SERN MO... THREAT FOR MAINLY DAMAGING WIND IS EXPECTED TO PERSIST FOR ANOTHER FEW HOURS AS MCS CONTINUES SWD INTO PARTS OF SERN MO. THIS ACTIVITY IS EXPECTED TO BEGIN AN OVERALL DECREASING TREND AS THE BOUNDARY LAYER BEGINS TO STABILIZE LATER THIS EVENING. ...LA THROUGH ERN TX... MCS WILL CONTINUE WSWWD INTO NERN TX NEXT FEW HOURS...BEFORE BEGINNING AN OVERALL DECREASING TREND LATER THIS EVENING AS THE BOUNDARY LAYER BEGINS TO STABILIZE. DAMAGING WIND WILL BE THE PRIMARY THREAT WITH THIS ACTIVITY. ..DIAL.. 07/20/2006  From swody1 at goshenarc.org Thu Jul 20 06:00:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 20 Jul 2006 02:00:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200557 SWODY1 SPC AC 200555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT THU JUL 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MID MS VALLEY...OH VALLEY THROUGH GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CNTRL AND NRN PLAINS... ...SYNOPSIS... UPPER PATTERN WILL REMAIN DOMINATED BY STRONGER WLYS FROM THE NRN ROCKIES THROUGH THE GREAT LAKES AREA. AN UPPER RIDGE WILL PERSIST OVER THE SRN TWO THIRDS OF THE COUNTRY. EMBEDDED WITHIN THE STRONGER WLYS AN UPPER TROUGH WILL CONTINUE EWD THROUGH SERN CANADA AND THE GREAT LAKES. FARTHER W...THE SHORTWAVE TROUGH CURRENTLY MOVING INTO THE NRN ROCKIES WILL BEGIN TO AMPLIFY SEWD INTO THE NRN HIGH PLAINS BY THURSDAY EVENING AS IT CRESTS THE UPPER RIDGE. A COLD FRONT WILL CONTINUE EWD THROUGH THE GREAT LAKES REGION IN ASSOCIATION WITH THE NRN STREAM UPPER TROUGH. THIS BOUNDARY WILL EXTEND SWWD INTO THE CNTRL PLAINS WHERE IT WILL BEGIN TO STALL. A SECONDARY FRONTAL SURGE WILL ACCOMPANY THE SHORTWAVE TROUGH SEWD INTO THE NRN HIGH PLAINS BY THURSDAY EVENING. ...MID MS VALLEY THROUGH THE OH VALLEY AND GREAT LAKES AREA... STEEP LAPSE RATES HAVE SPREAD EWD FROM THE PLAINS ABOVE HIGHER THETA-E AIR OVER THE MID MS VALLEY...RESULTING IN A RESERVOIR OF STRONG INSTABILITY THAT WILL PERSIST INTO THURSDAY. MLCAPE IS EXPECTED TO RANGE FROM 3500+ J/KG OVER PARTS OF THE MID MS VALLEY TO AROUND 1500 J/KG OR LESS OVER THE OH VALLEY AND GREAT LAKES REGION WHERE LAPSE RATES AND LOW LEVEL MOISTURE WILL BE MORE LIMITED. COMPLICATING FACTOR FOR THIS OUTLOOK WILL BE POTENTIAL FOR ONGOING STORMS EARLY IN THE PERIOD. ACTIVITY NOW OVER PARTS OF NERN IA AND SRN WI MAY CONTINUE SEWD INTO N CNTRL IL BY THE START OF THE PERIOD. THE LOW LEVEL JET IS FORECAST TO WEAKEN DURING THE DAY WITH LARGELY UNIDIRECTIONAL DEEP LAYER FLOW. AROUND 35-40 KT WLY 6 KM FLOW ACCOMPANYING THE UPPER TROUGH WILL CONTRIBUTE TO DEEP LAYER SHEAR SUFFICIENT FOR SOME ORGANIZED STORM STRUCTURES. HOWEVER...THE STRONGER FLOW IS EXPECTED TO REMAIN N OF THE BETTER INSTABILITY. CURRENT THINKING IS THAT ONGOING STORMS MAY RE-INTENSIFY AS THE DOWNSTREAM ATMOSPHERE DESTABILIZES. OTHER STORMS MAY DEVELOP IN ASSOCIATION WITH REMNANT OUTFLOW BOUNDARIES AND SPREAD EWD INTO THE OH VALLEY. PRIMARY THREATS WILL BE DAMAGING WIND AND HAIL. OTHER STORMS MAY DEVELOP FARTHER NE ALONG FRONT FROM THE GREAT LAKES INTO SRN CANADA. THIS ACTIVITY MAY REACH PARTS OF THE NERN U.S. OVERNIGHT WITH A THREAT OF ISOLATED DAMAGING WIND GUSTS. ....NRN HIGH PLAINS THROUGH CNTRL PLAINS... ESELY UPSLOPE COMPONENT ALONG SRN PERIPHERY OF SURFACE RIDGE WILL MAINTAIN BOUNDARY LAYER DEWPOINTS IN THE 50S OVER PARTS OF THE CNTRL AND NRN HIGH PLAINS. STEEP LAPSE RATES ABOVE THIS MOIST AXIS WILL CONTRIBUTE TO MODERATE INSTABILITY DURING THE AFTERNOON. STORMS WILL LIKELY DEVELOP INITIALLY OVER THE HIGHER TERRAIN AND THEN SPREAD SEWD INTO THE MOIST AXIS WHERE MODERATE INSTABILITY WILL EXIST. A BELT OF STRONGER 40 KT MID LEVEL FLOW ACCOMPANYING THE UPPER TROUGH WILL SPREAD SEWD ABOVE THE SELY LOW LEVEL FLOW CONTRIBUTING TO SUFFICIENT SHEAR FOR SUPERCELLS. OTHER STORMS MAY DEVELOP N OF THE SURFACE FRONT DURING THE EVENING AS THE LOW LEVEL JET STRENGTHENS WITH STORMS EVENTUALLY EVOLVING INTO ONE OR MORE MCSS. LARGE HAIL AND DAMAGING WIND WILL BE THE MAIN THREATS. ...SRN AZ... ELY FLOW ON SRN PERIPHERY OF UPPER RIDGE SUGGESTS STORMS THAT DEVELOP OVER THE RIM AND OVER THE HIGHER TERRAIN OF SERN AZ AND SWRN NM WILL HAVE POTENTIAL TO SPREAD INTO THE DESERT VALLEYS. TEMPERATURE/DEWPOINT SPREADS WILL BE SUFFICIENT FOR A THREAT OF MICROBURSTS. HOWEVER...COVERAGE IS EXPECTED TO REMAIN TOO ISOLATED FOR A SLIGHT RISK. ..DIAL/TAYLOR.. 07/20/2006  From swody1 at goshenarc.org Thu Jul 20 12:48:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 20 Jul 2006 08:48:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201240 SWODY1 SPC AC 201239 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 AM CDT THU JUL 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID MS/OH AND TN VALLEYS AND GREAT LAKES AREA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN HIGH PLAINS SEWD INTO CENTRAL PLAINS... ...SYNOPSIS... A TROUGH WILL BEGIN TO DEEPEN FROM THE NRN/CENTRAL ROCKIES EWD INTO THE NRN OHIO VALLEY AND NEW ENGLAND AS THE LARGE UPPER RIDGE SHIFTS WWD AND BEGINS TO BUILD NWD INTO THE PACIFIC NW. EMBEDDED WITHIN THIS AMPLIFYING TROUGH WILL BE ONE SHORTWAVE TROUGH MOVING THROUGH THE GREAT LAKES AND ANOTHER DROPPING SEWD FROM THE NRN ROCKIES INTO THE CENTRAL PLAINS. A COLD FRONT ASSOCIATED WITH THE DEEPENING TROUGH WILL MOVE EWD AND IS FORECAST TO EXTEND FROM THE EASTERN GREAT LAKES SWWD INTO MO AND THEN WWD INTO ERN CO BY LATE AFTERNOON. ...MID MS/OH/TN VALLEYS AND GREAT LAKES AREA... CONVECTIVE EVOLUTION AND SEVERE THREAT TODAY COMPLICATED BY ONGOING CONVECTION...BUT LARGE AREA OF INSTABILITY AND UNSEASONABLY HOT TEMPERATURES WITHIN A MOIST BOUNDARY LAYER WILL RESULT IN A LARGE SLIGHT RISK AREA. CURRENT THINKING IS WEAKENED BOW ECHO IN NRN IL/IND WILL MOVE SWD DURING THE DAY IN RESPONSE TO WLY LOW LEVEL JET AND INSTABILITY AXIS THAT CURRENTLY EXTENDS SWD FROM THE SYSTEM. WELL ORGANIZED COLD POOL/MESO HIGH SHOULD KEEP SYSTEM ORGANIZED UNTIL THE AIR MASS DESTABILIZES SUFFICIENTLY FOR REINTENSIFICATION OF THE SYSTEM. ALTHOUGH THE MID LEVEL WINDS/DEEP LAYER SHEAR WILL BE WEAKER ACROSS THE LOWER OH/TN VALLEY THAN ACROSS THE GREAT LAKES AREA...STRONG INSTABILITY...STEEP LAPSE RATES AND ORGANIZED OUTFLOW LIKELY WOULD KEEP THIS SYSTEM SEVERE AT LEAST AS FAR SOUTH AS TN. OTHER SEVERE STORMS MAY DEVELOP ALONG FRONT/OUTFLOW BOUNDARIES THIS AFTERNOON AND EVENING DUE TO STRONG INSTABILITY...MLCAPES RANGING FROM 3500+ J/KG MID MS VALLEY TO AROUND 1500 J/KG OVER THE OH VALLEY...AND STRENGTHENING WINDS ALOFT/SHEAR AS HEIGHTS SLOWLY FALL. GIVEN THE WARM MID LEVEL TEMPERATURES ALOFT...THE PRIMARY THREAT WILL BE DAMAGING WINDS. ....NRN/CENTRAL HIGH PLAINS... ESELY BOUNDARY LAYER WINDS BEHIND COLD FRONT WILL MAINTAIN DEWPOINTS IN THE 50S OVER PARTS OF THE CNTRL/NRN HIGH PLAINS. STEEP LAPSE RATES ABOVE THE MOIST AXIS WILL CONTRIBUTE TO MODERATE INSTABILITY THIS AFTERNOON. AS SHORTWAVE TROUGH MOVES SEWD INTO THE AREA...STORMS ARE EXPECTED TO DEVELOP OVER THE HIGHER TERRAIN. THOUGH THE WINDS ARE NOT FORECAST TO BE PARTICULARLY STRONG BELOW 500 MB...SELY BOUNDARY LAYER WINDS VEERING TO WLY IN THE LOWER 3KM WILL RESULT IN SUFFICIENT SHEAR FOR SUPERCELLS. AN ISOLATED TORNADO OR TWO MAY BE POSSIBLE WHEN THE STORMS FIRST DEVELOP...BUT AS OUTFLOWS MERGE...STORMS SHOULD ORGANIZE INTO AN MCS AND MOVE SEWD ALONG THE 850 MB TEMPERATURE GRADIENT AND INTO THE 25 KT LOW LEVEL JET. SEVERE HAIL WOULD BE THE PRIMARY THREAT EARLY AND THEN TRANSITION INTO MORE OF A DAMAGING WIND THREAT AS THE SYSTEM FORWARD PROPAGATES INTO WRN/CENTRAL NEB AND NRN KS. ...SWRN TX... UPPER WAVE THAT RESULTED IN SEVERE THUNDERSTORMS FROM AL INTO ERN TX WED WILL BE MOVING ACROSS SWRN TX DURING THE PERIOD OF MAX HEATING. ALTHOUGH THE BOUNDARY LAYER WILL NOT BE AS MOIST OR UNSTABLE AS IT WAS ACROSS THE CENTRAL GULF STATES... INVERTED-V SOUNDINGS SUGGEST STRONG/BRIEF SEVERE WIND GUSTS ARE POSSIBLE WITH STORMS. ...SRN AZ... ELY WINDS ARE FORECAST THROUGHOUT MUCH OF THE TROPOSPHERE ACROSS AZ TODAY. HOWEVER...WATER VAPOR IMAGERY SHOWS DRIER AIR SPREADING IN FROM NEW MEXICO AND THE CONVECTIVE COVERAGE WAS MOSTLY SUPPRESSED WITHIN THIS DRIER MID/HIGH LEVEL AIR MASS ON WED. STORMS CURRENTLY OVER SERN AZ SHOULD SHIFT WWD...BUT MORNING CLOUDS/PCPN SHOULD LIMIT HEATING/INSTABILITY SOMEWHAT. AS DRIER AIR MOVES IN FROM THE EAST...ONLY ISOLATED STORMS ARE EXPECTED OVER THE HIGHER TERRAIN OF SERN AZ THIS AFTERNOON. ..IMY.. 07/20/2006  From swody1 at goshenarc.org Sat Jul 22 05:57:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 01:57:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220554 SWODY1 SPC AC 220552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1252 AM CDT SAT JUL 22 2006 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE NERN STATES THROUGH THE MID ATLANTIC...SERN STATES...LOWER MS VALLEY AND SERN TX... ...SYNOPSIS... SYNOPTIC PATTERN WILL REMAIN DOMINATED BY AN UPPER TROUGH OVER THE OH VALLEY AND GREAT LAKES WITH A CLOSED UPPER RIDGE IN THE W. SERIES OF VORTICITY MAXIMA WILL ROTATE THROUGH THE UPPER TROUGH. ONE SUCH FEATURE NOW MOVING THROUGH THE BASE OF THE TROUGH AND INTO THE OH VALLEY WILL CONTINUE ENEWD INTO THE NERN STATES SATURDAY AFTERNOON. A SURFACE LOW WILL ACCOMPANY THE VORT MAX AND IS FORECAST TO UNDERGO SOME DEEPENING AS IT TRACKS NEWD ALONG THE SURFACE FRONT INTO PA BY AFTERNOON. NERN PORTION OF THIS FRONT WILL MOVE VERY LITTLE OR LIFT SLOWLY NWD...WHILE THE SWRN PORTIONS WILL CONTINUE SWD THROUGH THE SERN STATES AND S TX. ...MID ATLANTIC THROUGH SRN NEW ENGLAND... RICH LOW LEVEL MOISTURE EXISTS IN THE PRE-FRONTAL WARM SECTOR WITH DEWPOINTS IN THE LOWER 70S. PRIMARY CONCERN IS HOW SEVERAL MCSS NOW ONGOING FROM THE CNTRL APPALACHIANS WWD INTO THE OH VALLEY WILL EVOLVE. COLD POOL FROM MCS NOW ONGOING FROM WV SWD THROUGH WRN NC WAS APPARENTLY DEEP AND STRONG ENOUGH TO CROSS THE MOUNTAINS WITH NEW STORMS CONTINUING TO DEVELOP ALONG THE LEADING OUTFLOW. MUCH OF THE ATMOSPHERE IN THIS REGION HAS NOT BEEN OVERTURNED AND THERE IS CONCERN THAT STORMS MAY CONTINUE DEVELOPING INTO MUCH OF THE NIGHT...ESPECIALLY FROM VA SWD. MUCH OF THIS CONVECTION SHOULD REMAIN S OF THE MID ATLANTIC AND NERN STATES...BUT DEBRIS FROM UPSTREAM STORMS CURRENTLY OVER THE OH VALLEY COULD ALSO SERVE TO LIMIT HEATING AND INSTABILITY. WHERE POCKETS OF SURFACE HEATING DO DEVELOP...MLCAPE FROM 1000 TO 1500 J/KG WILL BE POSSIBLE GIVEN THE RICH LOW LEVEL MOISTURE IN PLACE. LOW LEVEL JET WILL STRENGTHEN WITHIN ZONE OF ASCENT AND HEIGHT FALLS E OF SURFACE LOW FROM NRN VA THROUGH ERN PA AND SRN NEW ENGLAND AS THE SHORTWAVE TROUGH ADVANCES EWD DURING THE DAY. THE STRENGTHENING LOW LEVEL WIND FIELDS AND MID LEVEL JET ACCOMPANYING THE SHORTWAVE TROUGH WILL CONTRIBUTE TO FAVORABLE KINEMATIC PROFILES FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND BOW ECHOES. LOW LEVEL STORM RELATIVE HELICITY FROM 200 TO 300 M2/S2 WILL POSE A THREAT FOR LOW LEVEL MESOCYCLONES AND TORNADOES WITH ANY DISCRETE STORM STRUCTURES. OTHERWISE DAMAGING WIND WILL BE POSSIBLE. HIGHER END SEVERE THREAT IS CONDITIONAL ON DEGREE OF INSTABILITY AND HOW MUCH ONGOING CONVECTION CONTAMINATES THE WARM SECTOR. WILL KEEP THIS AREA IN SLIGHT RISK FOR NOW DUE TO THE POTENTIAL LIMITING FACTOR. HOWEVER...AN UPGRADE TO MODERATE RISK MIGHT BE NEEDED IN LATER OUTLOOKS ONCE IT BECOMES CLEAR IF AND WHERE SUFFICIENT DESTABILIZATION WILL OCCUR. ...CAROLINAS THROUGH THE SERN STATES AND SERN TX... POSSIBILITY REMAINS THAT MCS NOW CROSSING THE APPALACHIANS WILL CONTINUE INTO THE MORNING...EXHAUSTING MUCH OF THE INSTABILITY AND REDUCING THE SEVERE THREAT OVER THE CAROLINAS. WILL LEAVE A SLIGHT RISK FOR NOW IN CASE THIS SCENARIO DOES NOT PLAY OUT AND THE ATMOSPHERE IS ABLE TO RECOVER. WEAK VERTICAL WIND PROFILES WILL SUPPORT MULTICELL STORMS IN PRE-FRONTAL WARM SECTOR WITH A THREAT FOR MAINLY ISOLATED DAMAGING WIND. FARTHER SW FROM GA THROUGH THE LOWER MS VALLEY AND S TX...MORE ABUNDANT SURFACE HEATING SHOULD ALLOW THE ATMOSPHERE TO BECOME MODERATELY UNSTABLE. SCATTERED MULTICELL STORMS WILL LIKELY INTENSIFY ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON WITH A THREAT FOR ISOLATED DAMAGING WIND GUSTS THROUGH MID EVENING. ...WI... A SHORTWAVE TROUGH WILL DROP SWD INTO THE UPPER MS VALLEY AND WRN GREAT LAKES AREA DURING THE DAY. RELATIVELY COOL MID LEVEL TEMPERATURES (-12C AT 500 MB) AND STRONG SURFACE HEATING WILL CONTRIBUTE TO STEEP LAPSE RATES AND MLCAPE AROUND 1000 J/KG. AS THE ATMOSPHERE DESTABILIZES...STORMS WILL LIKELY DEVELOP DURING THE AFTERNOON WITHIN ZONE OF ASCENT ASSOCIATED WITH THE SERN MOVING IMPULSE. THE THERMODYNAMIC ENVIRONMENT SUGGEST A FEW STORMS COULD PRODUCE GUSTY WINDS AND HAIL THROUGH EARLY EVENING. ..DIAL/CROSBY.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 12:37:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 08:37:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221233 SWODY1 SPC AC 221231 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0731 AM CDT SAT JUL 22 2006 VALID 221300Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NORTHERN AL/GA...ACROSS THE MID ATLANTIC REGION...INTO SOUTHERN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MN/IA... MORNING SATELLITE LOOPS SHOW WELL-DEFINED UPPER TROUGH ROTATING THROUGH THE OH VALLEY. THIS SYSTEM WILL BRING RATHER STRONG WIND FIELDS AND LIFT TO MUCH OF THE NORTHEAST AND MID ATLANTIC STATES TODAY...ALONG WITH A RISK OF SEVERE THUNDERSTORMS WHERE DAYTIME HEATING CAN OCCUR. ...SOUTHERN NEW ENGLAND INTO PA/NJ... SURFACE LOW NOW OVER NORTHWESTERN PA IS FORECAST TO DEEPEN AND TRACK EASTWARD ACROSS PA/NY AND INTO WESTERN NEW ENGLAND TODAY. A VERY MOIST AIR MASS WILL BE PRESENT IN WARM SECTOR OF LOW WITH DEWPOINTS IN THE 70S...BUT ALSO WITH SCATTERED CLOUD COVER AND SHOWERS. MODEL FORECAST SOUNDINGS FROM EASTERN PA/NJ NORTHWARD ACROSS SOUTHERN NEW ENGLAND SUGGEST UNSEASONABLY STRONG LOW/MID LEVEL WIND FIELDS WILL DEVELOP BY AFTERNOON /6KM SHEAR OF 35-45 KNOTS AND 0-3KM HELICITY OF 150-250 M2/S2/...FAVORABLE FOR SUPERCELL STORMS AND EVEN ISOLATED TORNADOES. HOWEVER...LACK OF STRONG HEATING WILL LIKELY MITIGATE OVERALL SEVERE THREAT ACROSS THIS REGION. PRESENT INDICATIONS ARE THAT ONGOING THUNDERSTORM ACTIVITY OVER PA/NY WILL PROGRESS EASTWARD...WITH SOME INTENSIFICATION POSSIBLE ALONG THE SOUTHEAST FRINGE OF STORMS ACROSS EASTERN PA/NJ AND SOUTHEAST NY. THESE STORMS WILL MOVE NORTHEASTWARD INTO SOUTHERN NEW ENGLAND BY LATE AFTERNOON. SURFACE TEMPERATURES IN THE LOWER 80S WILL BE SUFFICIENT FOR SURFACE-BASED STORMS AND A RISK OF SUPERCELLS. NORTHWARD EXTENT OF SEVERE THREAT WILL BE DICTATED BY CLOUD COVER AND ASSOCIATED SURFACE HEATING. DAMAGING WINDS AND ISOLATED TORNADOES APPEAR TO BE THE MAIN THREATS IN THIS REGION. ...MID ATLANTIC REGION... MORNING SHOWERS ARE EXPECTED TO DISSIPATE SOMEWHAT BY EARLY AFTERNOON...ALLOWING MODERATE DAYTIME HEATING FROM NORTHERN NC INTO MD/DE. SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER THE MOUNTAINS OF WESTERN NC/VA AND MOVE EASTWARD THIS AFTERNOON. SUFFICIENT WIND FIELDS ALOFT AND MODERATE INSTABILITY WILL PROMOTE A RISK OF DAMAGING WINDS IN STRONGER CELLS. ...CAROLINA COAST... STRONG HEATING OVER COASTAL NC/SC WILL ALLOW SEA BREEZE TO MOVE ONSHORE LATER THIS AFTERNOON. INTERACTION OF SEA BREEZE WITH CONVECTIVE OUTFLOWS FROM OVERNIGHT AND AFTERNOON THUNDERSTORMS MAY RESULT IN ISOLATED SEVERE STORMS CAPABLE OF DAMAGING WINDS. THREAT SHOULD DIMINISH RAPIDLY AFTER SUNSET. ...MN/IA... RELATIVELY STRONG NORTHWEST FLOW PATTERN WILL BE PRESENT TODAY OVER THE MIDWEST. FULL SUNSHINE AND STEEP LAPSE RATES WILL ALLOW AIRMASS TO BECOME MODERATELY UNSTABLE BY LATE AFTERNOON...DESPITE SURFACE DEWPOINTS ONLY IN THE LOW 60S. PRESENT INDICATIONS ARE THAT ISOLATED THUNDERSTORMS WILL DEVELOP OVER SOUTHEAST MN BY LATE AFTERNOON...SPREADING SOUTHWARD INTO IA DURING THE EVENING. BRIEF SUPERCELLS ARE POSSIBLE WITH A RISK OF HAIL AND GUSTY WINDS. ..HART/CROSBIE.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 16:43:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 12:43:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221640 SWODY1 SPC AC 221638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT SAT JUL 22 2006 VALID 221630Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND TO MID ATLANTIC STATES... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF UPPER MISSISSIPPI VALLEY... ...NERN U.S... SEASONABLY DEEP UPPER TROUGH ERN U.S. WITH VERY LARGE UPPER HIGH IN THE WEST. THE S/WV TROUGH DEPICTED ON W/V IMAGERY AND HEIGHT FALLS AT 12Z IS LIFTING NEWD ACROSS NY/PA ATTM WITH ASSOCIATED BAND OF STRONGER WIND FIELDS SPREADING ACROSS NERN U.S. AHEAD OF S/WV THIS AFTERNOON AND EVENING. SURFACE LOW AT 15Z NERN PA IS GRADUALLY DEEPENING AS IT TRACKS NEWD TO SERN NY LATER THIS AFTERNOON AND NRN VT/NH LATER TONIGHT. A VERY WARM AND MOIST AIRMASS IS SPREADING NEWD IN THE 30-35KT SWLY FLOW AHEAD OF LOW AND THE WEAK COLD FRONT WHICH TRAILS SWWD TO NRN GULF STATES. SHEAR PROFILES ARE IN PLACE TO SUPPORT SEVERE THUNDERSTORMS AND SUPERCELLS AHEAD OF SURFACE LOW FROM ERN DELMARVA NEWD INTO SRN NEW ENGLAND THIS AFTERNOON AND EVENING. THE PRIMARY CAVEAT IS SURFACE HEATING AS EXTENSIVE CLOUDINESS THIS AM IS ONLY SLOWLY THINNING. HOWEVER WITH ONLY WEAK CIN...AND HEATING NOW SHOWING E OF APPALACHIANS AS FAR N AS SRN PA...TEMPERATURES SHOULD RISE THRU THE 80S NWD THRU SERN NY BY MID AFTERNOON. THIS WILL RESULT IN MLCAPES INCREASING TO NEAR 2000 J/KG AS FAR N AS NJ/ERN NY AND 1000-1500 J/KG SRN NEW ENGLAND LATE THIS AFTERNOON. SURFACE BASED STRONG/SEVERE THUNDERSTORMS WILL DEVELOP BY 18Z AHEAD OF SURFACE LOW AND ALONG LEE TROUGH LOCATED TO E OF APPALACHIANS. PRIMARY THREAT WILL BE DAMAGING WINDS AS STORMS FORM INTO CLUSTERS AND LINES...HOWEVER 20-25KT OF SFC-1KM SHEAR AND LOW LCLS ALSO SUPPORT SUPERCELLS. GREATEST TORNADIC SUPERCELL POTENTIAL WOULD BE IN ENHANCED LOW LEVEL CONVERGENCE AHEAD OF LOW AND VICINITY THE SUBTLE WARM FRONT EXTENDING EWD THRU SRN NEW ENGLAND AND ALONG THE SURFACE LEE TROUGH THAT WILL BE LOCATED VICINITY PA/NJ BORDER LATER THIS AFTERNOON. ...MID ATLANTIC/GULF COAST STATES... WHILE SHEAR WILL BE WEAKER ACROSS THIS AREA...THE AIR MASS IS VERY MOIST AND POTENTIALLY QUITE UNSTABLE. GOOD HEATING UNDERWAY MUCH OF THE REGION AHEAD OF COLD FRONT WHICH HAS PROGRESSED TO NRN AL AND MS. THUNDERSTORMS WILL BE COMMON ALONG AND AHEAD OF COLD FRONT BY MID AFTERNOON AS MLCAPES CLIMB TO 2000 J/KG OR MORE. WITH DEEP LAYER SHEAR GENERALLY LESS THAN 20KT...STORM MODE SHOULD BE PULSE/MULTICELL. PRIMARY SEVERE THREAT WILL BE WET MICRO-BURSTS. SEVERE OCCURRENCE SHOULD BE GREATEST CAROLINAS WHERE SHEAR IS GREATER...DECREASING TO MORE ISOLATED COVERAGE GULF STATES. ...UPPER MS VALLEY... WEAK IMPULSE EMBEDDED IN NLY FLOW NOTED ON W/V IMAGERY DROPPING SWD THRU WI TODAY. OVERALL THE SHEAR OF 30KT OR LESS SUPPORT MULTICELL CONVECTIVE MODE. WITH FREEZING LEVELS NEAR 10K FT AND AFTERNOON HEATING GENERATING SBCAPE TO 1000-1500 J/KG A FEW SEVERE THUNDERSTORMS ARE LIKELY. PRIMARY THREAT WILL BE LARGE HAIL WITH THE EARLIER SLIGHT RISK AREA BEING SHIFTED EWD INTO WI WHERE TRACK OF UPPER SYSTEM IS LOCATED. ...SWRN U.S... VERY TO EXTREMELY HOT CONDITIONS CONTINUE UNDER LARGE UPPER HIGH. MOISTURE HAS CONTINUED TO INCREASE NWWD THRU W COAST STATES WITH PW/S GENERALLY 1.25 TO 1.5 NOTED. WITH VERY STEEP LAPSE RATES...THUNDERSTORMS WILL DEVELOP OVER HIGHER TERRAIN FROM NM/AZ NWWD THRU INTERIOR CA/WRN NV. ISOLATED SEVERE DOWNBURSTS ARE LIKELY AS STORMS DRIFT OFF MOUNTAINS LATER THIS AFTERNOON WITH MARGINALLY SEVERE HAIL ALSO POSSIBLE PRIMARILY OVER HIGHER TERRAIN. ..HALES/GRAMS.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 19:52:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 15:52:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221949 SWODY1 SPC AC 221947 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0247 PM CDT SAT JUL 22 2006 VALID 222000Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND SWD ALONG THE ATLANTIC COAST AND WWD ALONG THE GULF COAST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPPER MIDWEST... ...SRN NEW ENGLAND INTO THE CAROLINAS... AFTERNOON WATER VAPOR IMAGERY SHOWS VIGOROUS SHORT WAVE TROUGH LIFTING NEWD THROUGH THE LOWER GREAT LAKES WITH AN ACCOMPANYING BELT OF 35-45 KT SWLY MID-LEVEL FLOW FROM THE CNTRL APPALACHIANS INTO NEW ENGLAND. ATTENDANT SURFACE LOW OVER THE LOWER HUDSON VALLEY IS FORECAST TO CONTINUE NEWD THROUGH THE REMAINDER OF THE AFTERNOON AND TONIGHT WITH TRAILING COLD FRONT PUSHING TOWARD THE MIDDLE ATLANTIC COAST. THUS FAR...STRONGEST TSTM DEVELOPMENT HAS OCCURRED ALONG LEE TROUGH FROM VICINITY OF SURFACE LOW OVER SERN NY SWWD INTO CNTRL/ERN MD WHERE BREAKS IN THE CLOUDS HAVE ALLOWED FOR STRONGER DAYTIME HEATING. THIS ISOLATION COUPLED WITH DEWPOINTS OF 70-75 F ARE CONTRIBUTING TO MLCAPES OF 500-1500 J/KG. CURRENTLY...REGIONAL VWPS INDICATE THAT STRONGEST LOW AND DEEP-LAYER SHEAR /150-250 M2/S2 0-1 KM SRH AND 35-45 KTS OF 0-6 KM SHEAR/ EXISTS FROM NRN/CNTRL NJ NWD INTO THE SRN NEW ENGLAND AND THE MIDDLE HUDSON VALLEY...WHERE STRONGEST ISALLOBARIC RESPONSE IS OCCURRING E OF SURFACE LOW. HOWEVER...18Z ALBANY AND UPTON NY SOUNDINGS INDICATE THAT CONSIDERABLE CLOUDS AND PRECIPITATION HAVE LIMITED DESTABILIZATION WITHIN THIS REGION OF STRONGER SHEAR. EXPECT GREATEST SEVERE THREAT TO EXIST FROM SERN NY/NJ SSWWD INTO CHESAPEAKE BAY THIS AFTERNOON AND EVENING...WHERE BEST COMBINATION OF INSTABILITY AND STRONGER VERTICAL SHEAR WILL BE CO-LOCATED. HERE...POTENTIAL WILL EXIST FOR SMALL-SCALE BOWING STRUCTURES AND PERHAPS A SUPERCELL OR TWO CAPABLE OF MAINLY DAMAGING WINDS. GREATEST THREAT OF A TORNADO WILL LIKELY EXIST OVER SERN NY INTO SWRN NEW ENGLAND...SHOULD SUFFICIENT DESTABILIZATION OCCUR TO SUSTAIN DEEP CONVECTION. FARTHER S INTO THE CAROLINAS...VERTICAL SHEAR DECREASES WITH SWD EXTENT...THOUGH AIR MASS REMAINS HOT AND MOIST FROM VICINITY OF LEE TROUGH WWD TOWARD COLD FRONT. CONTINUED HEATING/DESTABILIZATION SHOULD SUPPORT AN INCREASE IN TSTM COVERAGE ALONG THESE BOUNDARIES LATE THIS AFTERNOON INTO THE EVENING WITH A THREAT OF LOCALLY DAMAGING WINDS WITH THE MOST INTENSE STORMS. ...GA WWD INTO THE LOWER MS VALLEY... WIDESPREAD TSTMS HAVE DEVELOPED THIS AFTERNOON ALONG AND AHEAD OF SURFACE COLD FRONT AND PRE-FRONTAL TROUGH FROM GA WWD INTO LA. TEMPERATURES IN THE 90S COUPLED WITH DEWPOINTS IN THE UPPER 60 TO LOWER/MID 70S ARE CONTRIBUTING TO A MODERATELY UNSTABLE PRE-FRONTAL AIR MASS WITH MLCAPES OF 1500-2500 J/KG. VERTICAL SHEAR REMAINS WEAK...THOUGH NE-SW ORIENTED TSTM BANDS FROM CNTRL AL INTO CNTRL LA WILL HAVE THE POTENTIAL TO ORGANIZE COLD POOLS AS THEY MOVE/DEVELOP SEWD. DAMAGING WINDS WILL BE THE MAIN SEVERE WEATHER THREAT. ...UPPER MIDWEST... TSTMS ARE BECOMING MORE NUMEROUS THIS AFTERNOON FROM WI INTO LOWER MI SWD INTO NERN IA AND NRN IL...IN ASSOCIATION WITH A SHORT WAVE TROUGH TRANSLATING SEWD THROUGH THE REGION. THOUGH BOUNDARY LAYER DEWPOINTS ARE NOT PARTICULARLY HIGH /MID 50S TO LOWER 60S/...THE PRESENCE OF STEEP LOW-LEVEL LAPSE RATES AND MODESTLY COOL MID-LEVEL TEMPERATURES /I.E. -14 TO -16 C AT 500 MB/ ARE CONTRIBUTING TO MLCAPES OF 500-1000 J/KG. REGIONAL VWPS AND PROFILERS INDICATE THAT THE STRONGEST VERTICAL SHEAR EXISTS TO THE W OVER WRN MN/IA IN ASSOCIATION WITH MID AND HIGH-LEVEL JET STREAKS DIGGING SWD. THEREFORE...EXPECT THAT STORMS WILL REMAIN MULTICELLULAR AND CAPABLE OF GUSTY WINDS AND SOME MARGINALLY SEVERE HAIL THROUGH THE EVENING HOURS. ...WRN STATES... WATER VAPOR IMAGERY SHOWS TWO WELL-DEFINED IMPULSES ROTATING AROUND UPPER HIGH...ONE MOVING SWD THROUGH CNTRL CO...AND THE OTHER SHIFTING WWD THROUGH THE LOWER CO VALLEY. THESE FEATURES COUPLED WITH STRONG DIABATIC HEATING ALONG THE HIGHER TERRAIN WILL SUPPORT AN INCREASE IN TSTM ACTIVITY THIS AFTERNOON INTO TONIGHT. THE MOST INTENSE STORMS WILL BE CAPABLE OF SEVERE MICROBURSTS OWING TO THE STRONG EVAPORATIONAL COOLING POTENTIAL IN THE SUB-CLOUD LAYER. ..MEAD.. 07/22/2006  From swody1 at goshenarc.org Sun Jul 23 01:15:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 21:15:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230111 SWODY1 SPC AC 230110 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0810 PM CDT SAT JUL 22 2006 VALID 230100Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND INTO THE CAROLINAS... ...SRN NEW ENGLAND INTO THE CAROLINAS... THUNDERSTORMS CONTINUE ALONG COLD FRONT FROM SRN NEW ENGLAND SWWD INTO GA AND THEN WSWWD INTO W TX. THOUGH A LIMITED/LOCAL SEVERE THREAT EXISTS ALONG THIS ENTIRE AREA...GREATEST THREAT EXISTS FROM SRN NEW ENGLAND INTO THE CAROLINAS WHERE MODERATE SWLY FLOW AT MID LEVELS IS INDICATED ALONG ERN PERIPHERY OF UPPER TROUGH. THOUGH THREAT SHOULD CONTINUE TO SLOWLY DECREASE WITH TIME AS DIURNAL STABILIZATION CONTINUES...LOCALLY-DAMAGING WINDS AND/OR MARGINAL HAIL -- AND PERHAPS EVEN AN ISOLATED/BRIEF TORNADO -- MAY STILL OCCUR WITH A FEW STRONGER STORMS/STORM CLUSTERS. ...THE SOUTHWEST/GREAT BASIN... SCATTERED THUNDERSTORMS CONTINUE FROM CO/NM ACROSS PARTS OF AZ AND UT INTO NV/CA/ORE/SRN ID -- ALL WITHIN LARGE-SCALE ANTICYCLONIC FLOW AROUND RIDGE CENTERED OVER THE GREAT BASIN. STORMS WILL LIKELY CONTINUE FOR SEVERAL HOURS -- AS SEVERAL VORTICITY MAXIMA CONTINUE ROTATING AROUND THE RIDGE. THOUGH WEAK FLOW AND MARGINAL INSTABILITY IN MOST AREAS WILL CONTINUE TO LIMIT THE SEVERE THREAT...A LOCALLY-DAMAGING GUST OR MARGINAL HAIL EVENT MAY OCCUR WITH A COUPLE OF THE STRONGEST STORMS. ...SRN UPPER GREAT LAKES REGION... THUNDERSTORMS CONTINUE A GENERAL DIURNAL DECREASE ACROSS THE UPPER MIDWEST/SRN UPPER GREAT LAKES REGION ATTM. THOUGH A FEW MARGINAL SEVERE EVENTS MAY OCCUR IN THE NEXT 1 TO 2 HOURS...THREAT SHOULD CONTINUE TO WANE WITH TIME. ..GOSS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 06:04:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 02:04:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230601 SWODY1 SPC AC 230559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT SUN JUL 23 2006 VALID 231200Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CAROLINAS AND INTO SERN VA... ...SYNOPSIS... UPPER PATTERN IS FORECAST TO DEAMPLIFY SLOWLY THIS PERIOD...AS WRN RIDGE FLATTENS WITH TIME AND ERN TROUGH LIFTS NEWD AND TAKES ON A NEGATIVE TILT. AT THE SURFACE...COLD FRONT WILL CONTINUE MOVING EWD ACROSS THE ATLANTIC COAST STATES WHILE LINGERING ACROSS THE GULF COAST REGION. A SECOND/WEAK FRONT SHOULD MOVE SEWD INTO THE UPPER MS VALLEY/SWD INTO MT THROUGH THE PERIOD. ...CAROLINAS/SERN VA... COLD FRONT MOVING SLOWLY EWD ACROSS THE E COAST STATES SHOULD YIELD SCATTERED THUNDERSTORMS...AS MOIST AIRMASS DESTABILIZES THROUGH THE AFTERNOON. INSTABILITY SHOULD REMAIN SOMEWHAT LIMITED DUE TO WEAK LAPSE RATES ACROSS THIS REGION ALONG WITH EXISTING CLOUDS/CONVECTION. HOWEVER...AMPLE DEEP-LAYER SHEAR -- AIDED BY 30 TO 40 KT WSWLY FLOW AT MID-LEVELS NEAR BASE OF UPPER TROUGH -- WILL SUPPORT ORGANIZED/SEVERE STORMS. THREAT SHOULD DIMINISH THROUGH THE EVENING AS AIRMASS STABILIZES AND FRONT MOVES OFFSHORE. A LESSER THREAT MAY EXTEND SWD ACROSS GA AND INTO NERN FL...AS WEAKER SHEAR WITH SWD EXTENT LIMITS POTENTIAL FOR ORGANIZATION. ...N CENTRAL CONUS... COLD FRONT IS FORECAST TO MOVE SEWD ACROSS THE UPPER MS VALLEY/SWD INTO MT/ND...AS SEVERAL UPPER DISTURBANCES MOVE SEWD WITHIN FAST NWLY FLOW ALOFT. THOUGH CAP SHOULD HINDER CONVECTIVE DEVELOPMENT ACROSS MUCH OF THE REGION...MARGINAL INSTABILITY COMBINED AND AMPLE LOW-LEVEL CONVERGENCE SHOULD YIELD SCATTERED STORM DEVELOPMENT ACROSS PARTS OF NRN MN AND INTO NWRN WI. STORM INITIATION IS LESS CERTAIN WITH WWD EXTENT ACROSS ND...THOUGH STRONGER FEATURE FORECAST TO MOVE INTO NWRN MT MAY YIELD A SECOND AREA OF MORE CONCENTRATED CONVECTIVE POTENTIAL. OVERALL HOWEVER...MARGINAL INSTABILITY AND LIMITED CONVECTIVE COVERAGE SUGGESTS ONLY A LOW-PROBABILITY THREAT ACROSS THIS REGION. ...THE SOUTHWEST... NELY FLOW ALOFT IS FORECAST ACROSS NM/ERN AZ THIS PERIOD...WITHIN SERN QUADRANT OF UPPER RIDGE. AS STORMS DEVELOP WITHIN ENVIRONMENT FEATURING MARGINAL INSTABILITY AND A DEEPLY-MIXED BOUNDARY LAYER...A LIMITED THREAT FOR LOCALLY-DAMAGING WINDS APPEARS TO EXIST. GREATEST THREAT APPEARS TO EXIST ACROSS WRN NM/SERN AZ WHERE SLIGHTLY STRONGER FLOW ALOFT IS EXPECTED...BUT OVERALL THREAT SHOULD REMAIN BELOW SLIGHT RISK CRITERIA. ...SRN ID AND VICINITY... THUNDERSTORMS ARE EXPECTED TO DEVELOP INVOF UPPER VORT MAX FORECAST ACROSS SRN ID DURING THE AFTERNOON...WITHIN AIRMASS FEATURING DEEP BOUNDARY LAYER AND MARGINAL INSTABILITY. THOUGH WEAK FLOW AND LIMITED INSTABILITY SUGGEST THAT OVERALL SEVERE THREAT SHOULD REMAIN LOW...A FEW STRONGER CELLS MAY BE CAPABLE OF LOCALLY STRONG WIND GUSTS AND MARGINAL HAIL THROUGH EARLY EVENING. ...LOWER GREAT LAKES REGION... AS COLD TROUGH SPREADS EWD ACROSS THE LOWER GREAT LAKES REGION...AFTERNOON HEATING WILL CONTRIBUTE TO MARGINAL DESTABILIZATION. SCATTERED/LOW-TOPPED STORMS SHOULD DEVELOP AND MOVE ESEWD WITHIN DEEP-LAYER WNWLY FLOW. THOUGH LIMITED INSTABILITY SHOULD MODULATE UPDRAFT INTENSITY...A LOCAL THREAT FOR HAIL AND/OR GUSTY WINDS IS ANTICIPATED WITH STRONGER CELLS THROUGH EARLY EVENING. ..GOSS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 12:43:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 08:43:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231240 SWODY1 SPC AC 231238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT SUN JUL 23 2006 VALID 231300Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF GA...THE CAROLINAS...AND SOUTHEAST VA... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF MN...WI...AND UPPER MI... ...GA/SC INTO MID ATLANTIC REGION... LARGE UPPER RIDGE WILL CONTINUE TO DOMINATE THE WEATHER OVER THE WESTERN STATES TODAY...WHILE BROAD TROUGH AND MODERATELY STRONG CYCLONIC FLOW ALOFT PROMOTES SCATTERED THUNDERSTORMS FROM THE CENTRAL GULF STATES INTO THE MID ATLANTIC REGION. EARLY VISIBLE IMAGERY SHOWS BROKEN HIGH CLOUDS OVER THIS AREA...WHICH SHOULD ALLOW FAIRLY STRONG HEATING FROM GA/SC INTO SOUTHEAST VA. SURFACE DEWPOINTS NEAR 70F...CAPE VALUES OF 1500-2000 J/KG...AND WEAK CAPPING WILL AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS BY MID AFTERNOON. WESTERLY MID LEVEL WINDS OF 25-35 KNOTS WILL HELP ORGANIZE STORMS IN THIS REGION...WITH BANDS OF CONVECTION CAPABLE OF DAMAGING WINDS AND HAIL EXPECTED. SEA BREEZE INTERACTIONS MAY ALSO ENHANCE SEVERE THREAT NEAR THE CAROLINA COAST THIS AFTERNOON. ...MN/WI/UPPER MI... WATER VAPOR IMAGERY SHOWS FAST-MOVING SHORTWAVE TROUGH DIGGING SOUTHEASTWARD ACROSS MANITOBA/SASKATCHEWAN. THIS FEATURE WILL LIKELY RESULT IN THUNDERSTORM DEVELOPING THIS AFTERNOON NEAR WINNIPEG...WITH ACTIVITY SPREADING SOUTHEASTWARD INTO PARTS OF NORTHERN MN/NORTHWEST WI/UPPER MI. STEEP MID LEVEL LAPSE RATES ARE FORECAST IN THIS REGION...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS/BOWS. LARGE HAIL AND DAMAGING WINDS ARE POSSIBLE IN STRONGER STORMS THIS AFTERNOON AND EVENING. ...NORTHERN ROCKIES... MODERATE WESTERLY FLOW IS PRESENT TODAY OVER THE NORTHERN ROCKIES...WITH UPPER LEVEL IMPULSE ROTATING OVER TOP OF RIDGE INTO ID/MT. SCATTERED THUNDERSTORMS ARE LIKELY TO FORM AHEAD OF SYSTEM THIS AFTERNOON...WHERE HOT SURFACE TEMPERATURES AND INVERTED-V THERMODYNAMIC PROFILES WILL SUPPORT A RISK OF GUSTY WINDS. ...SOUTHWEST STATES... BAND OF NORTHERLY/NORTHEASTERLY MID LEVEL WINDS EXTENDS FROM CO INTO SOUTHERN AZ. THIS AXIS WILL LIKELY SEE SCATTERED AFTERNOON THUNDERSTORMS. STEEP LOW LEVEL LAPSE RATES WILL PROMOTE A RISK OF GUSTY WINDS IN STRONGER CELLS...AND STRONGER MID LEVEL WINDS WILL HELP ORGANIZE STORMS AND MOVE THEM OFF THE HIGHER TERRAIN. ..HART/CROSBIE.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 16:35:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 12:35:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231631 SWODY1 SPC AC 231630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT SUN JUL 23 2006 VALID 231630Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS EASTERN CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MN WI AND UPPER MI... ...CAROLINAS... BROAD TROUGH ERN U.S. GRADUALLY FILLS AS S/WV TROUGH CURRENTLY OH VALLEY CONTINUES ENEWD ACROSS NEW ENGLAND BY 12Z MON. FRONTAL ZONE HAS SHIFTED SEWD EXTENDING FROM SRN VA ACROSS NRN GULF STATES TO CENTRAL TX. CONSIDERABLE CLOUDINESS ALONG AND SOME DISTANCE IN ADVANCE OF FRONT...HOWEVER ERN NC PARTICULARLY WILL BE ABLE TO HEAT UP WITH MINIMAL CLOUD COVER. WITH DEWPOINTS WELL INTO THE 70S AND TEMPERATURES BY MID AFTERNOON UPPER 80S...MLCAPES WILL CLIMB TO 2000 J/KG WITH STEEP LOW LEVEL LAPSE RATES. WITH S/WV PASSING BY TO THE NORTH...DEEP LAYER SHEAR OF 20-30KT WILL SUPPORT MULTICELL STORM DEVELOPMENT. INITIATION WILL BE MOST FAVORABLE ALONG SEA BREEZE FRONT AND IN AREAS THAT EXPERIENCE STRONGEST HEATING. WITH MARGINAL SHEAR AND MID LEVEL LAPSE RATES GENERALLY AROUND 6C/KM WET DOWNBURSTS AND MARGINALLY SEVERE HAIL SHOULD BE THE LIMIT OF SEVERE THREAT FROM MID AFTERNOON TIL AROUND SUNSET. ...MN WI AND UPPER MI... S/WV TROUGH NOTED ON WV IMAGERY DROPPING SEWD ACROSS CENTRAL MANITOBA TOWARD WRN ONTARIO. CURRENT WARM ADVECTION CLOUDINESS/PCPN MN ARROWHEAD AHEAD OF TROUGH SHOULD GRADUALLY SHIFT EWD THIS AFTERNOON ALLOWING HEATING AND STEEPENING LOW LEVEL LAPSE RATES TO SPREAD EWD ACROSS NRN MN. VEERING SHEAR PROFILES AHEAD OF S/WV TROUGH WILL PROVIDE FAVORABLE CONDITIONS FOR POTENTIAL FOR ORGANIZED STORMS TO DEVELOP OVER SRN MANITOBA AND DROP SEWD DURING AFTERNOON/EVENING INTO NRN MN AND EVENTUALLY NRN WI/WRN UP OF MI. INSTABILITY WILL BE SOMEWHAT LIMITED GIVEN AVAILABLE LOW LEVEL MOISTURE...HOWEVER STEEPENING LAPSE RATES SHOULD RAISE MLCAPES TO NEAR 1000 J/KG BY MID AFTERNOON. HAVE EXTENDED EARLIER SLIGHT RISK WWD ACROSS NRN MN WHERE LOW LEVEL BOUNDARIES COULD SET UP ON EDGE OF CURRENT BOUNDARY WATERS PCPN. WITH 30-40KT OF DEEP LAYER SHEAR...SHORT LINES/BOWS COULD EVOLVE OUT OF STORMS MOVING INTO NRN MN FOR A GREATER WIND DAMAGE THREAT. ...WRN U.S... VERY LARGE UPPER HIGH CONTINUES TO CONTROL WEATHER WRN U.S. CONSIDERABLE MID LEVEL MOISTURE CIRCULATING AROUND THE HIGH AND WITH THE INTENSE SURFACE HEATING...CONTINUES THE THREAT OF ISOLATED DIURNAL SEVERE STORMS. THE THREAT WILL BE MODULATED WHERE FULL HEATING CAN OCCUR AND VICINITY HIGHER TERRAIN. LARGE AREAS OF MID CLOUDINESS WHILE EXPECTED TO THIN WITH TIME...WILL LIMIT HEATING IN SOME REGIONS. HAVE NOT TRIED TO PINPOINT ANY PARTICULAR AREA WHERE POTENTIAL FOR HIGH BASED DOWNBURSTS OR MARGINAL HAIL COULD OCCUR. THUS THE LARGE AREA OF LOW SEVERE PROBABILITIES. ..HALES/GRAMS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 19:59:30 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 15:59:30 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231955 SWODY1 SPC AC 231953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT SUN JUL 23 2006 VALID 232000Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER NRN MN...NRN WI AND THE WRN UP OF MI... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER PORTIONS OF THE SRN ATLANTIC COAST... ...NRN MN/NRN WI/WRN UP OF MI... AFTERNOON WATER VAPOR IMAGERY SHOWS AMPLIFYING SHORT WAVE TROUGH DIGGING SEWD INTO WRN ONTARIO WITH A WEAKER SRN IMPULSE OVER FAR SERN MANITOBA. CONSIDERABLE CLOUDINESS HAS LIMITED DAYTIME HEATING OVER MUCH OF THE ARROWHEAD...THOUGH AIR MASS FROM N OF HIB WWD HAS WARMED INTO THE UPPER 80S/LOWER 90S. THIS HEATING COUPLED WITH RELATIVELY STEEP MID-LEVEL LAPSE RATES AND MODEST BOUNDARY LAYER MOISTURE ARE CONTRIBUTING TO A MODERATELY UNSTABLE ENVIRONMENT W OF THICKER CLOUD SHIELD WITH MLCAPES OF AROUND 1000 J/KG. BASED ON SATELLITE TRENDS AND LATEST SHORT TERM MODEL GUIDANCE...IT APPEARS THAT TSTMS WILL INCREASE IN COVERAGE LATE THIS AFTERNOON INTO TONIGHT ALONG DIFFERENTIAL HEATING BOUNDARY AND COLD FRONT /NOW PUSHING INTO NWRN MN/. CURRENT DLH VWP AND FORECAST SOUNDINGS INDICATE PRONOUNCED LOW-LEVEL HODOGRAPH CURVATURE WITH 30-40 KTS OF DEEP-LAYER SHEAR. THUS...EXPECT THE POTENTIAL FOR ORGANIZED SEVERE STORMS...INCLUDING SUPERCELLS CAPABLE OF DAMAGING WINDS AND LARGE HAIL. THIS THREAT MAY TEND TO DIMINISH BY LATE EVENING INTO OVERNIGHT AS BOUNDARY LAYER SLOWLY STABILIZES. A FEW OF THE MORE INTENSE ELEVATED STORMS WILL REMAIN CAPABLE OF SOME HAIL OVERNIGHT. FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1614. ...SRN ATLANTIC COAST... LINGERING CLOUDINESS HAS SLOWED DESTABILIZATION OF AIR MASS AHEAD OF WEAKENING FRONT ACROSS THE PIEDMONT AND COASTAL PLAIN THROUGH EARLY AFTERNOON. MORE RECENTLY...CLOUDS HAVE THINNED...ALLOWING FOR STRONGER DIABATIC HEATING WHICH HAS COMBINED WITH A MOIST BOUNDARY LAYER TO INCREASE MLCAPES TO 1000-2000 J/KG. AREA VWPS AND RUC OBJECTIVE FIELDS INDICATE THAT MID-LEVEL WINDS ARE GRADUALLY WEAKENING WITH THE SLOW NEWD MOVEMENT OF UPPER TROUGH. HOWEVER...AN AXIS OF 30-35 KT WSWLY FLOW STILL EXISTS ACROSS NRN NC WHICH IS ENHANCING SHEAR ACROSS NRN PORTIONS OF SLIGHT RISK AREA. GIVEN THE MODERATE INSTABILITY...EXPECT THAT STORMS SHOULD CONTINUE TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE LATE AFTERNOON AND EARLY EVENING HOURS WITH THE MAIN THREAT BEING LOCALLY DAMAGING WINDS WITH ANY OF THE MORE INTENSE DOWNBURSTS. FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1613. ..MEAD.. 07/23/2006  From swody1 at goshenarc.org Mon Jul 24 01:10:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 21:10:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240107 SWODY1 SPC AC 240105 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT SUN JUL 23 2006 VALID 240100Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS NRN MN/NWRN WI... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN CAROLINAS/E CENTRAL GA... ...NRN MN/NWRN WI... STRONG STORMS CONTINUE MOVING SEWD INTO NWRN WI ATTM...ROUGHLY ALONG WARM FRONT. HOWEVER...AIRMASS BECOMES LESS FAVORABLE WITH SWD EXTENT ACROSS WI...SO THIS CLUSTER OF STORMS SHOULD WEAKEN. ADDITIONAL DEVELOPMENT CANNOT BE RULED OUT ACROSS NRN MN...WHERE AMPLE INSTABILITY AND MODERATE NWLY FLOW EXISTS. HOWEVER...CONDITIONAL SEVERE POTENTIAL ACROSS THIS REGION SHOULD CONTINUE TO DECREASE AS BOUNDARY LAYER STABILIZES. ...ERN CAROLINAS/E CENTRAL GA... LIMITED SEVERE THREAT CONTINUES ACROSS THIS REGION...AS MOIST/UNSTABLE ENVIRONMENT PERSISTS AHEAD OF FRONT. THOUGH SHEAR REMAINS SUFFICIENT FOR ORGANIZED STORMS...STRONGEST CONVECTION HAS REACHED THE NC COAST...AND WILL CONTINUE MOVING OFFSHORE. REMAINING THREAT SHOULD SLOWLY DIMINISH THIS EVENING. ...CO/THE SOUTHWEST... WIDESPREAD THUNDERSTORMS ARE OCCURRING ONCE AGAIN ACROSS MUCH OF THE WEST -- WITHIN LARGE-SCALE ANTICYCLONIC CIRCULATION. STORMS REMAIN GENERALLY LIMITED IN INTENSITY...DUE TO WEAK INSTABILITY/WARM TEMPERATURES ALOFT. THOUGH A STRONGER STORM OR TWO MAY PRODUCE LOCALLY-GUSTY WINDS OR MARGINAL HAIL...THREAT WILL CONTINUE TO DECREASE THROUGH LATE EVENING. ..GOSS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 06:11:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 02:11:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240607 SWODY1 SPC AC 240606 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0106 AM CDT MON JUL 24 2006 VALID 241200Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER GREAT LAKES WWD INTO PARTS OF SD/NEB... ...SYNOPSIS... LESS-AMPLIFIED UPPER PATTERN IS FORECAST THIS PERIOD...THOUGH OVERALL FLOW FIELD -- FEATURING A RIDGE OVER THE SOUTHWEST AND A TROUGH OVER THE ERN CONUS -- WILL PERSIST. AT THE SURFACE...MODELS DIFFER IN LOCATION OF N CENTRAL U.S. BAROCLINIC ZONE. IN GENERAL...THIS FRONT SHOULD LIE FROM THE UPPER GREAT LAKES WSWWD INTO NEB...AND THEN NWWD ACROSS THE NRN HIGH PLAINS INTO MT. THIS BOUNDARY SHOULD SERVE AS A FOCUS FOR SCATTERED STRONG/LOCALLY-SEVERE STORMS...AS BELT OF MODERATE WNWLY MID-LEVEL FLOW SHOULD ALSO RESIDE ACROSS THIS REGION. ...UPPER GREAT LAKES REGION WWD INTO ERN SD/NERN NEB... CONVECTION IS LIEKLY TO BE ONGOING AT THE START OF THE PERIOD ACROSS PARTS OF THE UPPER GREAT LAKES/UPPER MS VALLEY REGION...BUT MARGINAL TO MODERATE DESTABILIZATION IS ANTICIPATED THROUGH THE AFTERNOON NEAR AND S OF THE FRONT. AS A RESULT...SCATTERED STORMS SHOULD REDEVELOP INVOF SURFACE BOUNDARY AS UPPER SHORT-WAVE TROUGH MOVES ACROSS THE AREA. THOUGH STRONGEST MID-LEVEL FLOW WILL LIKELY REMAIN FROM LK SUPERIOR NWD...MODERATE WLY/WNWLY FLOW THROUGH A DEEP LAYER APPEARS SUPPORTIVE ISOLATED SEVERE STORMS/STORM CLUSTERS...CAPABLE OF PRODUCING LOCALLY-DAMAGING WINDS AND HAIL. STORM COVERAGE SHOULD DECREASE WITH WWD EXTENT ACROSS SD AND NEB...WHERE PROGRESSIVELY STRONGER CAP AND WEAKER LARGE-SCALE FORCING ARE ANTICIPATED. THREAT WILL SLOWLY WANE THROUGH LATE EVENING/OVERNIGHT AS AIRMASS DIURNALLY STABILIZES. ...MT INTO THE DAKOTAS... MODELS SUGGEST THAT A SECOND SHORT-WAVE TROUGH SHOULD MOVE ACROSS MT DURING THE DAY...WITH ASSOCIATED WARM ADVECTION ANTICIPATED ACROSS THE NRN HIGH PLAINS. THOUGH INSTABILITY SHOULD BE LIMITED...ISOLATED STORM DEVELOPMENT IS EXPECTED. WITH MODERATE WNWLY FLOW AT MID LEVELS...SHEAR WILL SUPPORT A FEW STRONGER STORMS -- WITH LOCALLY-DAMAGING WINDS LIKELY TO BE THE GREATER SEVERE THREAT GIVEN FAIRLY DEEP/DRY SUB-CLOUD LAYER. SOME HINT EXISTS IN THE MODELS THAT ENHANCED WARM ADVECTION OVER THE NRN HIGH PLAINS MAY RESULT IN A LOCALLY-GREATER THREAT...BUT QUESTIONS REGARDING DEGREE OF INSTABILITY AND TIMING OF UPPER FEATURE PRECLUDE AN UPGRADE TO SLIGHT RISK ATTM. ..GOSS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 12:29:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 08:29:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241226 SWODY1 SPC AC 241224 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0724 AM CDT MON JUL 24 2006 VALID 241300Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MIDWEST ACROSS THE GREAT LAKES STATES... WEST-NORTHWEST FLOW PATTERN WILL BE PRESENT TODAY FROM THE NORTHERN PLAINS ACROSS THE GREAT LAKES REGION. WATER VAPOR IMAGERY SHOWS SEVERAL WEAK IMPULSES EMBEDDED WITHIN FLOW THAT WILL HELP TO INITIATE SCATTERED THUNDERSTORMS FROM THE NORTHERN ROCKIES INTO MI. OTHER SCATTERED CONVECTION IS EXPECTED TODAY BENEATH UPPER RIDGE OVER THE WESTERN STATES...AND OVER THE SOUTHEAST IN PLUME OF TROPICAL AIR. ...GREAT LAKES AND UPPER MIDWEST... SHORTWAVE TROUGH NOW ROTATING TOWARD LAKE SUPERIOR WILL PROGRESS INTO MI TODAY. RELATIVELY STRONG WESTERLY LOW LEVEL WINDS AHEAD OF SYSTEM WILL HELP TRANSPORT WARM/MOIST AIRMASS INTO REGION WITH AFTERNOON DEWPOINTS WELL INTO THE 60S AND MLCAPE VALUES OVER 1500 J/KG. THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID/LATE AFTERNOON ALONG WEAK SURFACE BOUNDARY FROM WEST CENTRAL MN...ACROSS WI...INTO NORTHERN LOWER MI. THIS ACTIVITY WILL LIKELY PERSIST THROUGH THE EVENING...SPREADING ACROSS THE REMAINDER OF LOWER MI. FORECAST SOUNDINGS SUGGEST FAVORABLE DEEP LAYER VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS CAPABLE OF HAIL AND DAMAGING WINDS. ...NORTHERN PLAINS... STRONG DAYTIME HEATING WILL HELP ISOLATED THUNDERSTORM DEVELOPMENT FROM MN WESTWARD ACROSS THE DAKOTAS. HOWEVER...WEAKER DEEP LAYER FLOW AND WARMER TEMPERATURES ALOFT WILL TEND TO MINIMIZE ORGANIZED SEVERE THREAT IN THESE AREAS. ...NORTHERN ROCKIES... SERIES OF WEAK SHORTWAVE TROUGHS ARE ROTATING AROUND RIDGE CENTERED OVER UT. ONE FEATURE IS NOW OVER CENTRAL ORE...AND WILL LIKELY MOVE INTO ID BY THIS AFTERNOON. ENHANCED LIFT AHEAD OF FEATURE WILL AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER THE MOUNTAINS OF ID/WESTERN MT. MEAGER LOW LEVEL MOISTURE WILL LIMIT CAPE. HOWEVER...DEEP MIXED BOUNDARY LAYER SUGGESTS A THREAT OF GUSTY WINDS IN STRONGER CELLS. ..HART/CROSBIE.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 16:19:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 12:19:58 -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 MON JUL 24 2006 VALID 241630Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS MIDWEST AND PORTIONS OF GREAT LAKES... ...GREAT LAKES AND UPPER MIDWEST... THE SEVERE THUNDERSTORM RISK ACROSS MN EWD TO MI THIS AFTERNOON WILL BE PRIMARILY DRIVEN BY BUOYANCY/INSTABILITY. THE DEEP LAYER SHEAR WILL FOR THE MOST PART BE MARGINAL AS THE UPPER SYSTEM CURRENTLY OVER ONTARIO CONTINUES EWD. COLD FRONT EXTENDING SWWD ACROSS LS/NWRN WI TO CENTRAL SD WILL CONTINUE SEWD AND PROVIDE FOCUS FOR INITIATION OF STRONG/SEVERE THUNDERSTORMS BY MID/LATE AFTERNOON. WITH TEMPS CLIMBING TO 90F AIR MASS WILL BECOME MODERATELY UNSTABLE WITH MLCAPES TO 2500 J/KG ACROSS SRN MN/WI AND 2000 J/KG LWR MI. AS MENTIONED PROGGED DEEP LAYER SHEAR AROUND 20KT MN/WI WHERE INSTABILITY WILL BE GREATEST THIS AFTERNOON...RANGING UPWARD TO 30-35KT OF SHEAR NRN LWR MI WITH A LITTLE LESS INSTABILITY..SUPPORTS GENERALLY MULTICELL STORM MODE. THUS A THREAT OF LOCALIZED DAMAGING WINDS AND MARGINALLY SEVERE HAIL EXPECTED TO DEVELOP BY MID AFTERNOON ALONG/AHEAD OF FRONT SRN MN/WI AND THEN SPREAD EWD INTO PORTIONS OF LOWER MI. SEVERE THREAT SHOULD DECREASE AFTER SUNSET GIVEN THE WEAKENING SHEAR AND MINIMAL UPPER SUPPORT. ...SRN AZ... EXAMINING 12Z SOUNDINGS AND LACK OF CLOUD COVER TO SLOW HEATING...THUNDERSTORMS SHOULD DEVELOP EARLY AFTERNOON CENTRAL MTNS AND HIGHER TERRAIN SERN AZ. WHILE MLCAPE OVER DESERT VALLEY WILL BE GENERALLY LESS THAN 1000 J/KG...THE DEEP BOUNDARY LAYER AS TEMPS HEAT TO 110F ALONG WITH DCAPES APPROACHING 2000 J/KG WILL SUPPORT PROPAGATION OF STORMS OFF HIGHER TERRAIN IN THE PREVAILING ELY STEERING FLOW. STRONG...POSSIBLY DAMAGING OUTFLOW WINDS EXPECTED TO SPREAD WWD INTO LOWER ELEVATIONS LATE THIS AFTERNOON AND EVENING. ...NRN PLAINS WWD TO WRN MT... AS LARGE UPPER HIGH OVER WRN U.S. GRADUALLY FLATTENS...MID LEVEL WLYS INCREASE ACROSS NRN TIER OF STATES. WEAK UPPER IMPULSES...ONE NOW MOVING EWD INTO WRN MT WILL AID DEVELOPMENT OF HIGH BASED THUNDERSTORMS. WHILE MOISTURE IS MARGINAL...STRONG HEATING/STEEP LAPSE RATES AND 30KT OF DEEP LAYER SHEAR WILL SUPPORT LOCAL STRONG DOWNBURSTS WITH ANY STORM THAT CAN DEVELOP ACROSS MT AND ADJACENT HIGH PLAINS LATER THIS AFTERNOON/EVENING. ..HALES/GRAMS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 19:53:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 15:53:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241948 SWODY1 SPC AC 241946 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0246 PM CDT MON JUL 24 2006 VALID 242000Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER GREAT LAKES AND UPPER MS VALLEY.... ...SYNOPSIS... MINOR SHORTWAVE IS EMBEDDED WITHIN NORTHWEST FLOW ACROSS PARTS OF THE UPPER MIDWEST. LATEST SURFACE ANALYSIS SHOWS COLD FRONT EXTENDING FROM CENTRAL LAKE SUPERIOR SWWD ACROSS NWRN WI AND CENTRAL MN INTO NRN SD. MEANWHILE...LARGE MID/UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE SWRN U.S. ...PARTS OF THE GREAT LAKES AND UPPER MS VALLEY... STRONG/SEVERE THUNDERSTORMS EXTENDED FROM NRN LAKE MI WWD THRU NRN WI ALONG FRONTAL BOUNDARY. AIR MASS S OF THIS BOUNDARY IS VERY MOIST...WARM AND UNSTABLE WITH DEW POINTS IN THE MID/UPR 60S AND MLCAPE BETWEEN 1500 AND 2500 J/KG. LATEST RUC SOUNDING DATA SHOWS GRB WITH A SFC-3KM LAPSE RATE OF 8.5C/KM AND A DCAPE OF 1074 J/KM. WHILE SOME HAIL IS POSSIBLE...THIS WOULD INDICATE THAT THE MAIN THREAT WILL BE DAMAGING WINDS. FURTHER WEST...MODELS INDICATE THAT STORMS COULD DEVELOP THIS EVENING EAST OF SURFACE LOW OVER CENTRAL SD AND MOVE ALONG CONVECTIVE BOUNDARY AS INDICATED BY ELEVATED STORMS OVER SWRN MN. THIS ACTIVITY AS WELL LOOKS TO MOSTLY A THREAT FOR DAMAGING WINDS THRU EARLY TONIGHT. ...PARTS OF SERN AZ... NELY/ELY FLOW ALOFT REMAINS OVER ERN AND SRN AZ ACCORDING TO LATEST WATER VAPOR IMAGERY. SCATTERED THUNDERSTORMS CAN BE EXPECTED AGAIN LATER THIS AFTERNOON AND EARLY TONIGHT WHERE VERY STEEP MID LEVEL LAPSE RATES ARE NEAR 8.5C/KM. SOME OF THESE STORMS COULD PRODUCE SOME STRONG WIND GUSTS AS DCAPE VALUES ARE JUST ABOVE 1500 J/KG IN REGIME OF LARGE TEMP AND DEW POINT SPREADS OF AROUND 50 DEGREES. ..MCCARTHY.. 07/24/2006  From swody1 at goshenarc.org Tue Jul 25 01:49:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 21:49:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250054 SWODY1 SPC AC 250053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT MON JUL 24 2006 VALID 250100Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE GREAT LAKES AND UPPER MS VALLEY... ...GREAT LAKES AND UPPER MS VALLEY... WEAK COLD FRONT EXTENDED FROM THE ERN U.P. SWWD INTO NRN WI/SRN MN/SRN SD THIS EVENING. SCATTERED STRONG/SEVERE THUNDERSTORMS WERE LOCATED ALONG AND SOUTH OF THE FRONT WHERE THE AIR MASS WAS MODERATELY UNSTABLE. THE AMOUNT OF INSTABILITY AND UNIDIRECTIONAL WNWLY WINDS THROUGHOUT MUCH OF THE TROPOSPHERE FAVOR SMALL THUNDERSTORM LINES WITH THE POTENTIAL FOR MARGINALLY SEVERE WINDS/HAIL. HOWEVER...STORM INTENSITIES AND COVERAGE SHOULD DECREASE DURING THE EVENING AS STORM OUTFLOWS GRADUALLY STABILIZE/COOL THE BOUNDARY LAYER. SEVERE STORMS WERE ALSO LOCATED ACROSS SERN SD...WHERE STRONGLY VEERING WIND PROFILES WERE RESULTING IN STRONGER DEEP LAYER SHEAR THAN ACROSS THE GREAT LAKES. THESE STORMS WERE LOCATED NEAR THE COLD FRONT AND ON THE ERN EDGE OF A VERY HOT AIR MASS THAT STRETCHED ACROSS SRN SD/NRN NEB. THIS HEAT ENERGY PLUS THE PRESENCE OF THE LOW LEVEL JET IS LIKELY TO SUSTAIN THIS CONVECTION THROUGH THE EVENING WITH THE POTENTIAL FOR WIND/HAIL DAMAGE...REFERENCE WW 641. ...CENTRAL AZ... THE CENTER OF THE UPPER RIDGE WAS LOCATED NEAR THE FOUR CORNERS AREA THIS EVENING...WITH NELY/ELY MID LEVEL WINDS LOCATED ACROSS SRN AZ. NUMEROUS THUNDERSTORMS WERE LOCATED ACROSS THE NRN HALF OF THE STATE AND ARE LIKELY TO PROPAGATE SLOWLY SWWD. VERY HOT TEMPERATURES AND VERY STEEP LOW LEVEL LAPSE RATES MAY SUPPORT ISOLATED STRONG/SEVERE WIND GUSTS FOR THE NEXT COUPLE OF HOURS. ...NRN MT... CLUSTER OF STORMS WILL MOVE ESEWD THROUGH THE EVENING. DEEP MIXED BOUNDARY LAYER MAY SUPPORT STRONG WIND GUSTS FOR THE NEXT HOUR OR SO. ..IMY.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 05:17:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 01:17:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250513 SWODY1 SPC AC 250511 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1211 AM CDT TUE JUL 25 2006 VALID 251200Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS IN NRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MIDWEST/WRN GREAT LAKES... ...SYNOPSIS... A COUPLE OF SHORTWAVE TROUGHS WILL DIG SEWD FROM THE NRN ROCKIES INTO THE GREAT LAKES AREA...WHERE A WEAK LONGWAVE TROUGH IS CURRENTLY SITUATED. THE FIRST SHORTWAVE TROUGH WILL WEAKEN AND MOVE INTO NRN MN LATE TUESDAY AFTERNOON...WHILE A STRONGER TROUGH DIVES SEWD TO NEAR LAKE SUPERIOR BY WED MORNING. IN ASSOCIATION WITH THESE TROUGHS...A WEAK COLD FRONT WILL PUSH EWD INTO THE ERN DAKOTAS DURING THE AFTERNOON...WHILE THE REMNANTS OF THE FRONT THAT MOVED ACROSS MN/WI MONDAY...ARE FORECAST TO STRETCH ACROSS CENTRAL MN/WI DURING THE AFTERNOON HOURS. OTHERWISE...AN UPPER TROUGH IN QUEBEC WILL BRUSH NEW ENGLAND AND A MID/UPPER LEVEL TROUGH OVER THE NWRN GULF OF MEXICO IS FORECAST TO LIFT SLOWLY NWD TOWARD THE TX COAST. ...NRN NEW ENGLAND... STRONG FORCING ASSOCIATED WITH QUEBEC TROUGH SHOULD RESULT IN A BAND OF THUNDERSTORMS TO MOVE EWD ACROSS THE REGION TODAY. DUE TO STRONG WINDS ALOFT...DEEP LAYER SHEAR WILL BE SUFFICIENT FOR SEVERE STORMS. THE NEGATIVE FOR SEVERE WEATHER WILL BE POOR LAPSE RATES...WEAK INSTABILITY...MLCAPES LESS THAN 1000 J/KG AND THE POSSIBILITY OF HEATING BEING RESTRICTED DUE TO CLOUDS. HOWEVER... IF SOME HEATING OCCURS AND THE STORMS DEVELOP INTO BANDS/LINES... THEN THE ENVIRONMENTAL WINDS WOULD BE SUPPORTIVE OF ISOLATED SEVERE WIND GUSTS. THE STORMS SHOULD END BY EARLY EVENING AS THE MAIN LARGE SCALE LIFTING MOVES NEWD OUT OF THE AREA. ...UPPER MIDWEST/WRN GREAT LAKES REGION... THOUGH CONVECTIVE INITIATION IS SOMEWHAT UNCLEAR ACROSS THE AREA...THINK STORMS WILL BE INITIATED TUESDAY AFTERNOON ALONG COLD FRONT MOVING THROUGH THE ERN DAKOTAS. ALSO...A SEPARATE AREA OF THUNDERSTORMS SHOULD FORM ACROSS SRN/CENTRAL MN/WI BY LATE AFTERNOON AS LOW LEVEL JET STRENGTHENS AND IMPINGES UPON SURFACE BOUNDARY. AIR MASS ACROSS THE TWO AREAS WILL BE MODERATELY UNSTABLE AND DEEP LAYER SHEAR FROM 25-35 KT SHOULD SUPPORT CLUSTERS OF SEVERE MULTICELLS. THE ERN DAKOTA STORMS SHOULD WEAKEN SHORTLY AFTER SUNSET AS THEY MOVE EWD INTO A MORE STABLE BOUNDARY LAYER. THE STORMS OVER SRN/CENTRAL MN/WI MAY REMAIN STRONG UNTIL MID EVENING AS LOW LEVEL JET PROVIDES ADDITIONAL LIFT. HOWEVER... EXPECT THESE STORMS TO WEAKEN THEREAFTER AS THE AIR MASS STABILIZES FROM OUTFLOWS AND A DEEPENING STABLE BOUNDARY LAYER. THE STORMS MAY DEVELOP/SOUTHWARD INTO NRN IA/IL AS THE LOW LEVEL JET VEERS...BUT EXPECT THIS ELEVATED CONVECTION TO REMAIN MOSTLY NON-SEVERE. ...SOUTHWESTERN U.S.... MID/HIGH LEVEL MOISTURE CIRCULATING AROUND UPPER HIGH AND INCREASE IN BOUNDARY LAYER MOISTURE FROM THE SOUTH SUGGESTS SCATTERED THUNDERSTORMS SHOULD ONCE AGAIN DEVELOP ACROSS THE HIGHER TERRAIN OF NRN/ERN AZ DURING THE AFTERNOON. ENELY MID LEVEL WINDS AT 10 TO 15 KT SHOULD CARRY THE STORMS INTO THE DESERT FLOORS WHERE TEMPERATURES WILL BE ABOVE 100F...RESULTING IN VERY STEEP LOW LEVEL LAPSE RATES. THIS SUGGESTS THE POSSIBILITY OF ISOLATED STRONG/SEVERE WIND GUSTS...THOUGH THE SLOW MOTION OF STORMS PRECLUDES A SLIGHT RISK ATTM. ...UPPER TX COAST... AS MID/UPPER LEVEL LOW OVER THE NWRN GULF MOVES SLOWLY NWD AND POSSIBLY INTENSIFIES...LOW AND DEEP LAYER SHEAR PROFILES ARE FORECAST TO STRENGTHEN ACROSS THE REGION BY LATE TUESDAY NIGHT. THOUGH THE AIR MASS WILL BE QUITE WARM AND MOIST...INSTABILITY WILL BE LIMITED. HOWEVER...IF CELLULAR STORMS CAN DEVELOP...SHEAR WOULD SUPPORT SUPERCELLS AND THE VERY SMALL POSSIBILITY OF A TORNADO TOWARD THE END OF THE PERIOD. ..IMY.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 12:39:35 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 08:39:35 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251235 SWODY1 SPC AC 251234 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 AM CDT TUE JUL 25 2006 VALID 251300Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MIDWEST AND WESTERN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF NORTHERN NEW ENGLAND... ...MIDWEST STATES AND WESTERN GREAT LAKES... MORNING WATER VAPOR LOOPS SHOW SERIES OF SHORTWAVE TROUGHS TRACKING EAST-SOUTHEASTWARD ACROSS THE CANADIAN PRAIRIES...THE GREAT LAKES...AND INTO NEW ENGLAND. ONE FEATURE IS CURRENTLY OVER SOUTHEAST MANITOBA AND WILL TRACK INTO MN BY THIS EVENING. RELATIVELY STRONG HEATING IS EXPECTED AHEAD OF THIS SYSTEM FROM THE EASTERN DAKOTAS INTO MN/WI/MI...WHERE DEWPOINTS WELL INTO THE 60S AND STEEP LOW LEVEL LAPSE RATES WILL RESULT IN MLCAPE OVER 1000 J/KG. SEVERAL CLUSTERS OF THUNDERSTORMS ARE LIKELY TO FORM OVER THESE REGIONS THIS AFTERNOON...BOTH ALONG THE FRONT OVER WESTERN MN/EASTERN SD...AND EASTWARD INTO WI/MI IN LOW LEVEL WARM ADVECTION REGIME. FAVORABLE DEEP LAYER VERTICAL SHEAR PROFILES WILL PROMOTE ORGANIZED MULTICELL OR SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. OTHER MORE ISOLATED THUNDERSTORMS ARE LIKELY TO FORM IN PARTS OF NORTHEAST NEB/NORTHWEST IA WHERE HOT SURFACE TEMPERATURES WILL HELP REACH CONVECTIVE TEMPERATURE. THESE STORMS WILL HAVE THE POTENTIAL TO PERSIST INTO THE EVENING AND SPREAD ACROSS MUCH OF IA WITH A RISK OF DAMAGING WINDS. ...NORTHERN NEW ENGLAND... SHORTWAVE TROUGH OVER WESTERN QUEBEC WILL TRACK ACROSS NORTHERN NEW ENGLAND TODAY. RADAR/SATELLITE IMAGERY SHOWS WIDESPREAD CONVECTION OVER NORTHERN ME WHICH WILL LIMIT DAYTIME HEATING. HOWEVER...MODERATE INSTABILITY WILL LIKELY DEVELOP ALONG SOUTHERN PERIPHERY OF PRECIPITATION...HELPING STORMS TO INTENSIFY BY EARLY AFTERNOON. MODEL FORECAST SOUNDINGS SHOW 30-40 KNOT 6KM VERTICAL SHEAR VALUES FAVORABLE FOR A THREAT OF ISOLATED SEVERE THUNDERSTORMS. DAMAGING WINDS AND HAIL WILL BE POSSIBLE IN STRONGER CELLS. ...CENTRAL HIGH PLAINS... PLUME OF RICH MID LEVEL MOISTURE IS EVIDENT IN WATER VAPOR IMAGERY FROM THE FOUR CORNERS REGION INTO NEB. STRONG DAYTIME HEATING IS EXPECTED IN THIS AXIS...ESPECIALLY FROM EASTERN CO INTO NEB. SCATTERED THUNDERSTORMS ARE LIKELY TO FORM OVER THE FOOTHILLS OF CO AND SPREAD EASTWARD INTO THE ADJACENT PLAINS. DEEP...MIXED BOUNDARY LAYER WILL PROMOTE THREAT OF GUSTY WINDS IN STRONGER CELLS. ACTIVITY MAY SPREAD AS FAR EAST AS WESTERN KS BEFORE DIMINISHING LATE TONIGHT. ..HART/TAYLOR.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 16:25:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 12:25:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251622 SWODY1 SPC AC 251620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT TUE JUL 25 2006 VALID 251630Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS NORTH CENTRAL STATES... ...NCENTRAL U.S... SERIES OF S/WV TROUGHS MOVING IN THE WNWLY FLOW FROM SRN CANADA TO NEW ENGLAND. ONE IMPULSE CURRENTLY MOVING ESEWD CANADIAN PRAIRIE PROVINCES REACHING WRN GREAT LAKES BY 12Z WED. SURFACE FEATURES OF IMPORTANCE ARE THE TROUGH LOCATED FROM ERN SD SWWD INTO NWRN KS AND A WEAK COOL FRONT NOW PUSHING EWD ACROSS WRN ND INTO ERN WY AHEAD OF THE S/WV TROUGH. A WARM AND POTENTIALLY MDT TO VERY UNSTABLE AIR MASS IS IN PLACE ACROSS MUCH OF THE NCENTRAL U.S. WITH DEWPOINTS IN THE MID 60S TO NEAR 70F COMMON FROM ERN DAKOTAS/NEB TO WRN GREAT LAKES. WITH STRONG DAYTIME HEATING MUCH OF AREA...THUNDERSTORMS WILL DEVELOP VICINITY OF BOTH THE FRONTAL SYSTEM AND SURFACE TROUGH BY MID AFTERNOON. WITH MLCAPES RANGING UPWARDS TO 2500 J/KG AND LAPSE RATES GENERALLY 7C/KM OR GREATER...LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. IDENTIFYING THE MOST FAVORABLE REGION FOR THE HIGHER SEVERE POTENTIAL IS DIFFICULT WITH THE GENERALLY WEAK LOW LEVEL FLOW AND CONVERGENCE OVER MUCH OF THE NCENTRAL STATES. HOWEVER AS THE UPPER TROUGH APPROACHES...CONDITIONS WOULD FAVOR MORE ORGANIZED SEVERE POTENTIAL DEVELOPING BY LATE THIS AFTERNOON ACROSS SRN MN/NRN IA IN AREA OF POOLED MOISTURE/INSTABILITY. AN MCS COULD THEN PROPAGATE INTO WI THIS EVENING WITH ASSOCIATED SEVERE THREAT. ...NEW ENGLAND... BAND OF CLOUDINESS/PCPN THAT HAS SPREAD EWD ACROSS NRN NH/VT AND MAINE...EXPECTED TO LIMIT HEATING/DESTABILIZATION THIS AFTERNOON IN AREA OF EARLIER SLIGHT RISK. S/WV TROUGH SWINGING EWD ACROSS QUEBEC HAS ENHANCED SHEAR PROFILES ACROSS MUCH OF NEW ENGLAND. THINNING OF CLOUDS WILL ALLOW SOME HEATING THIS AFTERNOON NRN NEW ENGLAND. HOWEVER STILL EXPECT INSUFFICIENT INSTABILITY TO DEVELOP TO SUPPORT ORGANIZED SEVERE THREAT. A FEW STRONG/SEVERE STORMS ARE LIKELY...PARTICULARLY ACROSS WRN/NRN NY EWD ALONG THE SRN EDGE OF CURRENT CLOUDINESS. ...SWRN U.S... GULF SURGE UNDERWAY WITH VERY MOIST AIR MASS SPREADING NWD ACROSS SERN CA DESERTS AND MUCH OF SRN AZ. WITH STEEP LAPSE RATES IN PLACE THE LOW LEVEL MOISTURE INCREASE SHOULD RESULT IN A SUBSTANTIALLY MORE UNSTABLE AIR MASS THIS AFTERNOON S OF MOGOLLON RIM WWD TO SRN CA MTS. WITH MLCAPES OVER THE DESERTS RISING TO WELL ABOVE 2000 J/KG THE PRIMARY QUESTION REGARDING A SEVERE THREAT IS STORM INITIATION. STEERING FLOW IS GENERALLY WEAK ELY TO THE S OF 4 CORNERS UPPER HIGH. STORMS WILL DEVELOP OVER HIGHER TERRAIN DURING AFTERNOON AND SLOWLY PROPAGATE TOWARD LOWER ELEVATIONS. IF THE STEERING FLOW WAS STRONGER WOULD CONSIDER A SLIGHT RISK...BUT FOR NOW WILL JUST ADD LOW PROBABILITIES OF BOTH WIND AND HAIL. ..HALES/JEWELL.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 19:59:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 15:59:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251955 SWODY1 SPC AC 251954 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0254 PM CDT TUE JUL 25 2006 VALID 252000Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST.... ...SYNOPSIS... LATEST WATER VAPOR IMAGERY DEPICTS VERY WELL MID/UPPER LEVEL SHORTWAVE TROUGH MOVING SEWD ACROSS MANITOBA AND SERN SASKATCHEWAN. THIS WILL CONTINUE TO MOVE SEWD THE REMAINDER OF THE PERIOD AS STRONG MID/UPPER LEVEL RIDGE COVERS THE SWRN QUARTER OF THE U.S. IN ADDITION...MID/UPPER LEVEL TROUGH WILL CONTINUE TO MOVE NWD FROM THE NERN MEXICAN COAST INTO THE MIDDLE TX COAST REGION. ...UPPER MIDWEST... LATEST SURFACE ANALYSIS SHOWS WEAK COLD FRONTAL BOUNDARY EXTENDING FROM EXTREME NWRN MN TO A LOW OVER THE CENTRAL ND/SD BORDER...THEN NWWD THRU SERN AND N CENTRAL MT. THIS IS DEVELOPING INTO SOMEWHAT OF A COMPLEX SITUATION AS THERE HAVE BEEN SHOWERS/ISOLATED THUNDERSTORMS OVER PARTS OF THE MIDDLE MO VALLEY THUS FAR AND CONVECTION HAS FIRED ALONG THE FRONTAL BOUNDARY OVER NWRN MN INTO EAST CENTRAL ND. THIS ACTIVITY WILL BE MOVING INTO AN AXIS WITH VERY UNSTABLE AIR WHERE MLCAPES RANGE BETWEEN 2000 AND 2500 J/KG FROM NERN SD SEWD INTO SWRN WI AND NRN IL. IT LOOKS LIKE THERE ARE TWO SITUATIONS WHERE SEVERE WEATHER CAN DEVELOP THRU EARLY TONIGHT ACROSS THE UPPER MIDWEST. FIRST...EXPECT FRONTAL BOUNDARY DEVELOPMENT TO CONTINUE AND INTENSIFY AS IT MOVES SEWD FEEDING ON THE THERMODYNAMICS FROM SD INTO IL. SECOND WILL BE THE BOUNDARIES IN THE VICINITY OF ELEVATED CONVECTION OVER SERN SD/ERN NEB/WRN IA. STORMS COULD REINTENSIFY OVER IA WHERE MLCAPE HAS REACHED 3000 J/KG ALLOWING BOUNDARIES TO BE PRESENT AHEAD OF APPROACHING COLD FRONT LATER THIS EVENING AND TONIGHT. THUS...WITH BOTH SCENARIOS LOOKS LIKE MAIN THREAT WILL BE STRONG DAMAGING WINDS AND SOME HAIL ACROSS THE REGION. ...LOWER GREAT LAKES... LAKE BREEZE THUNDERSTORMS HAVE DEVELOPED FROM SWRN NY STATE SWWD INTO NERN OH. ACTIVITY IS WITHIN AREA WHERE MLCAPES ARE AROUND 1000 J/KG AHEAD OF WEAK VORTICITY MAX MOVING EWD OVER EXTREME SERN ONTARIO JUST ALONG THE NERN SHORES OF LAKE ERIE. MID LEVEL LAPSE RATES ARE AROUND 7C/KM WHICH WOULD BE SUPPORTIVE OF GUSTY WINDS WITH THUNDERSTORM ACTIVITY. WOULD ANTICIPATE MORE SCATTERED STRONG THUNDERSTORMS TO DEVELOP IN CU FIELD THAT IS EXTENDING NEWD TOWARDS NRN VERMONT AGAIN WITH THE THREAT BEING MAINLY GUSTY WINDS. ...PARTS OF THE DESERT SOUTHWEST... SEE MESOSCALE DISCUSSION 1624 FOR THE LATEST INFORMATION ON SEVERE THUNDERSTORM POTENTIAL. ..MCCARTHY.. 07/25/2006  From swody1 at goshenarc.org Wed Jul 26 01:05:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 21:05:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260100 SWODY1 SPC AC 260058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT TUE JUL 25 2006 VALID 260100Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE UPPER MIDWEST/WESTERN GREAT LAKES REGION... ...UPPER MIDWEST AND WESTERN GREAT LAKES... WATER VAPOR IMAGERY THIS EVENING SHOWS ONE SHORTWAVE TROUGH IS MOVING THROUGH WRN MN/NWRN IA...WHILE A STRONGER SYSTEM WAS DROPPING SEWD THROUGH ERN ND. A COLD FRONT AND A BAND OF THUNDERSTORMS...ASSOCIATED WITH THE ERN ND SYSTEM...WERE MOVING SEWD THROUGH CENTRAL MN WWD INTO SERN SD. MODERATE INSTABILITY AND FORCING WILL RESULT IN A FEW SEVERE STORMS THROUGH MID EVENING... REFERENCE WW 642. LARGE AREA OF MID/HIGH CLOUDS WERE LOCATED AHEAD OF THE MN SHORTWAVE TROUGH FROM ERN NEB ACROSS WRN/NRN IA INTO SWRN WI. SURFACE BASED AND MORE INTENSE CONVECTION DEVELOPED IN THE WARMER AIR MASS TO THE EAST OF THE DENSE CLOUDS IN ERN IA. STORMS ARE EXPECTED TO CONGEAL INTO A CLUSTER/LINE WITH THE RESULTANT COLD POOL LIKELY TO INCREASE THE SEVERE WIND THREAT AS THE LOW LEVEL JET STRENGTHENS OVERNIGHT AND PUSHES THE STORMS EWD INTO NRN IL... REFERENCE WW 644. OTHER STRONG/SEVERE STORMS IN NRN WI AND THE U.P. SHOULD CONTINUE MOVING NEWD THROUGH THE EVENING WITH A THREAT FOR HAIL AND MARGINALLY SEVERE WIND GUSTS...REF 643 DESPITE EXTENSIVE MID/HIGH CLOUDS...AIR MASS ACROSS ERN NEB/WRN IA REMAINS MODERATELY UNSTABLE. AS LOW LEVEL JET INCREASES OVERNIGHT ...ELEVATED STORMS ARE POSSIBLE. CONVECTIVE INITIATION IN THIS AREA IS UNCERTAIN...BUT THE AMOUNT OF INSTABILITY AND VEERING WIND PROFILES IN THE LOWER 3 KM WOULD SUPPORT SEVERE STORMS...REF MCD 1626. ...NY... THUNDERSTORMS WERE INITIATED ALONG THE LAKE BREEZE EARLIER TODAY AND HAVE REMAINED STRONG/SEVERE INTO THE EARLY EVENING HOURS. HOWEVER BUF AND ALY EVENING SOUNDINGS SHOW UPDRAFT ROOTS WILL BECOME DECOUPLED FROM THE BOUNDARY LAYER WITH A FEW MORE DEGREES OF COOLING...SO STORMS SHOULD WEAKEN BELOW SEVERE CRITERIA SHORTLY. ...DESERT SOUTHWEST... BAND OF STORMS WEST OF TUS ARE IN A LITTLE STRONGER MID LEVEL ELY FLOW AND WITH MODERATE INSTABILITY...ISOLATED SEVERE HAIL/WINDS ARE EXPECTED WITH THIS CONVECTION AS IT MOVES WSWWD. ANOTHER BAND OF STORMS WAS MOVING SLOWLY SWD OFF THE RIM AND EXTENDED FROM NORTH OF IGM TO EAST OF PRC. WHILE MLCAPE VALUES ABOVE 2000 J/KG WOULD SUPPORT A SEVERE THREAT...THE WEAK WINDS ALOFT AND SLOW STORM MOTION SUGGESTS HAIL/WIND WITH THESE STORMS SHOULD BE LOCALIZED. ..IMY.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 05:23:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 01:23:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260519 SWODY1 SPC AC 260518 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1218 AM CDT WED JUL 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN GREAT LAKES SWWD INTO THE MID MS VALLEY REGION... ...SYNOPSIS... BROAD UPPER TROUGH WILL EXTEND FROM THE NRN ROCKIES EWD INTO THE MID/UPPER MS VALLEY AND THEN NEWD INTO NEW ENGLAND...WHILE A RIDGE COVERS MOST OF THE COUNTRY. A WELL DEFINED SHORTWAVE TROUGH WITHIN THIS BROAD TROUGH...CURRENTLY LOCATED IN NRN MN...WILL MOVE SEWD THROUGH THE GREAT LAKES AREA TODAY. WEAK FRONTAL SYSTEM BY LATE AFTERNOON WILL EXTEND FROM THE WRN GREAT LAKES SWWD INTO SRN IA/SRN NEB...WITH A SURFACE TROUGH FORECAST TO STRETCH FROM NERN MO SWWD INTO SRN KS. AN UPPER TROUGH...WHICH HAS BEEN SITUATED OVER THE WRN GULF THE PAST FEW DAYS...IS PROGGED TO LIFT NWD INTO SERN TX DURING THE DAY WEDNESDAY. ...ERN GREAT LAKES AREA AND MIDDLE MS VALLEY REGION... UNCERTAINTIES EXIST CONCERNING CONVECTIVE INITIATION POTENTIAL AND EVOLUTION FOR SEVERE WEATHER. STRONGEST FORCING FOR CONVECTION WILL BE ASSOCIATED WITH SHORTWAVE TROUGH THAT IS EXPECTED TO BE LOCATED OVER WI AT 18Z AND MOVE EAST OF LOWER MI AFTER 00Z. DEEP LAYER SHEAR WILL BE FAVORABLE FOR SEVERE STORMS...BUT INSTABILITY IS LIKELY TO BE WEAK AS WIDESPREAD CONVECTION/CLOUDS OVERSPREAD LOWER MI THIS MORNING. IF SOME HEATING CAN OCCUR FROM LATE MORNING THROUGH EARLY AFTERNOON PRIOR TO THE TROUGH PASSAGE...A FEW STORMS WITH WIND DAMAGE WOULD BE POSSIBLE. STORMS ARE ALSO EXPECTED TO BE ONGOING AT DAYBREAK ACROSS EXTREME ERN IA ON THE NOSE OF THE LOW LEVEL JET. IF REMNANT CONVECTION/ OUTFLOW BOUNDARY FROM THESE STORMS CAN BE MAINTAINED EWD THROUGH MID MORNING...THE STORMS WOULD LIKELY INTENSIFY AS THEY MOVE INTO A WARMING/DESTABILIZING AIR MASS. WIND AND HAIL WOULD BE POSSIBLE WITH THESE STORMS. OTHER STORMS MAY DEVELOP LATE AFTERNOON/EVENING ACROSS SRN IA/NRN MO WHERE THE AIR MASS WILL BE CAPPED THROUGH MUCH OF THE DAY...ALLOWING THE ENVIRONMENT TO BECOME STRONGLY UNSTABLE WITH MLCAPES NEAR 3000 J/KG. THE WARM TEMPERATURES ALOFT WOULD INHIBIT LARGE HAIL. TEMPERATURES NEAR 100F...30 DEGREE SPREADS...AND STEEP MID LEVEL LAPSE RATES WOULD SUPPORT A DAMAGING WIND THREAT. OTHER HIGH BASED STORMS MAY ALSO DEVELOP SWWD ALONG THE SURFACE TROUGH INTO PORTIONS OF ERN/SRN KS. ...ERN TX AND LA... LATEST ETA/GFS MODELS BOTH LIFT GULF TROUGH NWD TODAY WITH STRONGEST WINDS LOCATED ACROSS FAR ERN TX AND LA. MOIST ADIABATIC LAPSE RATES AND CONSIDERABLE CLOUDS WILL LIMIT THE SEVERE POTENTIAL. HOWEVER...STORMS THAT DEVELOP AND MOVE NWD INTO AREAS THAT HAVE WARMED INTO THE 90S WILL ENCOUNTER A MODERATELY UNSTABLE AIR MASS AND A POTENTIAL FOR STRONG/SEVERE WIND GUSTS. ...SRN AZ... DESPITE WEAK WINDS ALOFT...STORMS ORGANIZED LATE TUESDAY AND THE DEVELOPMENT OF A STRONG COLD POOL PUSHED STRONG/SEVERE STORMS SWD THROUGH SRN AZ. MOISTURE SURGE FROM TROPICAL STORM EMILIA WILL MAINTAIN A MOIST BOUNDARY LAYER AND IF SUFFICIENT HEATING OCCURS AFTER CLOUDS CLEAR IN THE MORNING...ORGANIZED SEVERE STORMS ARE POSSIBLE AGAIN. HOWEVER...SOME CONCERN THAT CONVECTIVE OVERTURNING THIS EVENING MAY RESULT IN WEAKER CONVECTION...SO ONLY LOW PROBABILITIES FORECAST ATTM. ...ERN PA NEWD INTO NRN NEW ENGLAND... WEAK TROUGH IS FORECAST ACROSS THE AREA AND MODERATE INSTABILITY ALONG WITH WEAK CAPPING SHOULD RESULT IN SCATTERED AFTERNOON THUNDERSTORMS. A FEW STRONG WIND GUSTS/HAIL EVENTS ARE POSSIBLE GIVEN THE AMOUNT OF INSTABILITY...THOUGH THE WEAK WIND FIELDS/SHEAR SUGGEST THAT THE THREAT IS LOW. ..IMY/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 06:22:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 02:22:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260619 SWODY1 SPC AC 260617 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0117 AM CDT WED JUL 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN GREAT LAKES SWWD INTO THE MID MS VALLEY REGION... ...SYNOPSIS... BROAD UPPER TROUGH WILL EXTEND FROM THE NRN ROCKIES EWD INTO THE MID/UPPER MS VALLEY AND THEN NEWD INTO NEW ENGLAND...WHILE A RIDGE COVERS MOST OF THE COUNTRY. A WELL DEFINED SHORTWAVE TROUGH WITHIN THIS BROAD TROUGH...CURRENTLY LOCATED IN NRN MN...WILL MOVE SEWD THROUGH THE GREAT LAKES AREA TODAY. WEAK FRONTAL SYSTEM BY LATE AFTERNOON WILL EXTEND FROM THE WRN GREAT LAKES SWWD INTO SRN IA/SRN NEB...WITH A SURFACE TROUGH FORECAST TO STRETCH FROM NERN MO SWWD INTO SRN KS. AN UPPER TROUGH...WHICH HAS BEEN SITUATED OVER THE WRN GULF THE PAST FEW DAYS...IS PROGGED TO LIFT NWD INTO SERN TX DURING THE DAY WEDNESDAY. ...ERN GREAT LAKES AREA AND MIDDLE MS VALLEY REGION... UNCERTAINTIES EXIST CONCERNING CONVECTIVE INITIATION POTENTIAL AND EVOLUTION FOR SEVERE WEATHER. STRONGEST FORCING FOR CONVECTION WILL BE ASSOCIATED WITH SHORTWAVE TROUGH THAT IS EXPECTED TO BE LOCATED OVER WI AT 18Z AND MOVE EAST OF LOWER MI AFTER 00Z. DEEP LAYER SHEAR WILL BE FAVORABLE FOR SEVERE STORMS...BUT INSTABILITY IS LIKELY TO BE WEAK AS WIDESPREAD CONVECTION/CLOUDS OVERSPREAD LOWER MI THIS MORNING. IF SOME HEATING CAN OCCUR FROM LATE MORNING THROUGH EARLY AFTERNOON PRIOR TO THE TROUGH PASSAGE...A FEW STORMS WITH WIND DAMAGE WOULD BE POSSIBLE. STORMS ARE ALSO EXPECTED TO BE ONGOING AT DAYBREAK ACROSS EXTREME ERN IA ON THE NOSE OF THE LOW LEVEL JET. IF REMNANT CONVECTION/ OUTFLOW BOUNDARY FROM THESE STORMS CAN BE MAINTAINED EWD THROUGH MID MORNING...THE STORMS WOULD LIKELY INTENSIFY AS THEY MOVE INTO A WARMING/DESTABILIZING AIR MASS. WIND AND HAIL WOULD BE POSSIBLE WITH THESE STORMS. OTHER STORMS MAY DEVELOP LATE AFTERNOON/EVENING ACROSS SRN IA/NRN MO WHERE THE AIR MASS WILL BE CAPPED THROUGH MUCH OF THE DAY...ALLOWING THE ENVIRONMENT TO BECOME STRONGLY UNSTABLE WITH MLCAPES NEAR 3000 J/KG. THE WARM TEMPERATURES ALOFT WOULD INHIBIT LARGE HAIL. TEMPERATURES NEAR 100F...30 DEGREE SPREADS...AND STEEP MID LEVEL LAPSE RATES WOULD SUPPORT A DAMAGING WIND THREAT. OTHER HIGH BASED STORMS MAY ALSO DEVELOP SWWD ALONG THE SURFACE TROUGH INTO PORTIONS OF ERN/SRN KS. ...ERN TX AND LA... LATEST ETA/GFS MODELS BOTH LIFT GULF TROUGH NWD TODAY WITH STRONGEST WINDS LOCATED ACROSS FAR ERN TX AND LA. MOIST ADIABATIC LAPSE RATES AND CONSIDERABLE CLOUDS WILL LIMIT THE SEVERE POTENTIAL. HOWEVER...STORMS THAT DEVELOP AND MOVE NWD INTO AREAS THAT HAVE WARMED INTO THE 90S WILL ENCOUNTER A MODERATELY UNSTABLE AIR MASS AND A POTENTIAL FOR STRONG/SEVERE WIND GUSTS. ...SRN AZ... DESPITE WEAK WINDS ALOFT...STORMS ORGANIZED LATE TUESDAY AND THE DEVELOPMENT OF A STRONG COLD POOL PUSHED STRONG/SEVERE STORMS SWD THROUGH SRN AZ. MOISTURE SURGE FROM TROPICAL STORM EMILIA WILL MAINTAIN A MOIST BOUNDARY LAYER AND IF SUFFICIENT HEATING OCCURS AFTER CLOUDS CLEAR IN THE MORNING...ORGANIZED SEVERE STORMS ARE POSSIBLE AGAIN. HOWEVER...SOME CONCERN THAT CONVECTIVE OVERTURNING THIS EVENING MAY RESULT IN WEAKER CONVECTION...SO ONLY LOW PROBABILITIES FORECAST ATTM. ...ERN PA NEWD INTO NRN NEW ENGLAND... WEAK TROUGH IS FORECAST ACROSS THE AREA AND MODERATE INSTABILITY ALONG WITH WEAK CAPPING SHOULD RESULT IN SCATTERED AFTERNOON THUNDERSTORMS. A FEW STRONG WIND GUSTS/HAIL EVENTS ARE POSSIBLE GIVEN THE AMOUNT OF INSTABILITY...THOUGH THE WEAK WIND FIELDS/SHEAR SUGGEST THAT THE THREAT IS LOW. ..IMY/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 12:38:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 08:38:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261233 SWODY1 SPC AC 261232 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0732 AM CDT WED JUL 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VALLEY ACROSS THE GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF EAST TX AND WESTERN LA... ...MID MS VALLEY AND GREAT LAKES REGION... MORNING WATER VAPOR IMAGERY SHOWS VIGOROUS SHORTWAVE TROUGH DIGGING SOUTHEASTWARD ACROSS MN/WI INTO THE GREAT LAKES REGION. THIS FEATURE HAS MAINTAINED AN AREA OF WEAK CONVECTION OVER IA/IL/MO OVERNIGHT. STORMS ARE LIKELY TO WEAKEN THIS MORNING...BEFORE INCREASING AGAIN THIS AFTERNOON FROM CENTRAL IL INTO IND. STRONG HEATING AHEAD OF ACTIVITY WILL RESULT IN MLCAPE VALUES OVER 2000 J/KG. MODERATELY STRONG WESTERLY FLOW ALOFT WILL ALSO HELP TO ORGANIZE STORMS...WITH INTENSE MULTICELLS CAPABLE OF DAMAGING WINDS AND HAIL. ACTIVITY MAY SPREAD INTO WESTERN OH DURING THE EVENING BEFORE WEAKENING. FARTHER NORTH...MAIN SURFACE FRONT/CONVERGENCE AXIS WILL STRETCH FROM WI INTO UPPER MI BY MID AFTERNOON. RATHER COOL TEMPERATURES ALOFT AND STRONG HEATING WILL HELP TO DESTABILIZE THIS AREA...LEADING TO SCATTERED THUNDERSTORMS. ACTIVITY SHOULD SPREAD ACROSS LOWER MI DURING THE LATE AFTERNOON WITH A RISK OF HAIL AND DAMAGING WINDS. ...AR/TX... UPPER LEVEL LOW IS MOVING SLOWLY NORTHWARD NEAR THE UPPER TX GULF COAST. LOW LEVEL WIND FIELDS HAVE BECOME RATHER STRONG ON EAST SIDE OF LOW...WITH 40-50 KNOT SOUTHERLY 850MB WINDS FORECAST THIS AFTERNOON INTO PARTS OF EAST TX/WESTERN LA. A VERY MOIST AIR MASS IS IN PLACE WITH DEWPOINTS IN THE LOWER 70S...LEADING TO SETUP SIMILAR TO A WEAK TROPICAL SYSTEM. ISOLATED CELLS IN THIS REGION HAVE SHOWN LOW LEVEL ROTATION THIS MORNING...AND THREAT SHOULD CONTINUE THROUGH THE DAY AS DIURNAL HEATING ENHANCES INSTABILITY. ...NY/PA INTO NEW ENGLAND... ISOLATED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON ACROSS PARTS OF THE NORTHEAST U.S...WHERE FULL SUNSHINE AND DEWPOINTS WELL INTO THE 60S ARE EXPECTED. WARM TEMPERATURES ALOFT AND WEAK VERTICAL SHEAR WILL TEND TO LIMIT UPDRAFT INTENSITY. HOWEVER...SOME DRY AIR ALOFT AND STEEP LOW LEVEL LAPSE RATES WILL PROMOTE A RISK OF GUSTY WINDS IN STRONGEST CELLS. ...DESERT SOUTHWEST... GULF SURGE CONTINUES TODAY AS DEWPOINTS RISE THROUGH THE 60S OVER SOUTHERN/WESTERN AZ. OVERNIGHT CONVECTION IS WEAKENING RAPIDLY...WHICH SHOULD ALLOW STRONG DESTABILIZATION AGAIN THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON OVER THE MOUNTAINS OF SOUTHWEST NM/EASTERN AZ AND PROPAGATE WESTWARD. UPGRADE TO SLIGHT RISK MAY BE REQUIRED THIS AFTERNOON AS AREAS OF STRONG HEATING BECOME MORE APPARENT AND LOW LEVEL MOISTURE TRENDS CAN BE MONITORED. ..HART/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 16:22:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 12:22:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261617 SWODY1 SPC AC 261615 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1115 AM CDT WED JUL 26 2006 VALID 261630Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS MID MS VALLEY TO GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ERN TX AND LA... ...SYNOPSIS... AS UPPER HIGH IN THE W HAS GRADUALLY WEAKENED A WNWLY FLOW WITH SEVERAL EMBEDDED S/WV TROUGHS PREVAILS ACROSS THE NRN TIER OF THE CONUS. THE STRONGEST IMPULSE CURRENTLY MOVING EWD ACROSS THE UPPER GREAT LAKES AND OH VALLEY. A RATHER WEAK SURFACE FRONTAL ZONE EXTENDS FROM UPPER MI SWWD ACROSS SRN MN TO NERN CO. A TROPICAL LOW PRESSURE CENTER HAS MOVED INLAND FROM NWRN GULF TO A POSITION NW OF VCT ATTM. A MDTLY STRONG SLY FLOW OF TROPICAL AIR CONTINUES TO STREAM INLAND ACROSS ERN TX/WRN LA. ...MID MS VALLEY AND GREAT LAKES REGION... MUCH OF THREAT AREA IS CURRENTLY CLOUD COVERED WHICH WILL DELAY SEVERE THUNDERSTORM DEVELOPMENT UNTIL LATER THIS AFTERNOON. STRONGER BAND OF DEEP LAYER SHEAR ASSOCIATED WITH THE UPPER S/WV TROUGH MOVING ACROSS THIS AREA WILL SUPPORT MULTICELL THUNDERSTORMS ONCE AIR MASS CAN DESTABILIZE WITH AFTERNOON HEATING. THE AIR MASS IS VERY MOIST ACROSS THIS REGION AND WILL JUST REQUIRE SUFFICIENT HEATING TO WEAKEN CIN TO ALLOW SURFACE BASED STORMS TO DEVELOP. SURFACE CONVERGENCE IS RATHER WEAK BUT THE FRONTAL ZONE AS WELL AS OUTFLOW BOUNDARIES FROM OVERNIGHT CONVECTION SHOULD FOCUS INITIATION BY MID/LATE AFTERNOON. PRIMARY THREAT WILL BE LOCAL DAMAGING WIND AND MARGINALLY SEVERE HAIL GIVEN THE MULTICELL NATURE OF THE CONVECTION. ...ERN TX/LA... WITH THE MODELS INDICATING THE LOW LEVEL CIRCULATION NOW ONSHORE SCENTRAL TX CONTINUING A SLOW NNEWD MOVEMENT ACROSS ERN TX THIS FORECAST PERIOD...A THREAT OF TROPICAL SUPERCELLS WILL CONTINUE AND SHIFT INLAND AS WELL. 20-30KT OF SFC-1KM SHEAR AND HELICITIES UPWARDS TO 200 M2/S2 EXPECTED TO MAINTAIN A THREAT OF SUPERCELLS AND ISOLATED TORNADOES. THE CURRENT THREAT AREA SERN TX/SWRN LA COAST WILL SHIFT INLAND THIS AFTERNOON IN CONCERT WITH THE LOW MOVEMENT. ...SWRN U.S... TUESDAYS GULF SURGE FOLLOWED BY ACTIVE OVERNIGHT CONVECTION SRN AZ HAS TRANFORMED MUCH OF THE AZ DESERTS AIR MASS INTO A VERY MOIST AND MODERATELY UNSTABLE ENVIRONMENT. THE STABILIZING EFFECT OF THE NIGHTTIME ACTIVITY WILL REDUCE SOMEWHAT THE THREAT OF SEVERE THUNDERSTORMS TODAY. HOWEVER WITH THE MID CLOUD COVER EVAPORATING...HEATING EXPECTED TO BE SUFFICIENT TO ALLOW MLCAPES TO CLIMB BACK TO NEAR 2000 J/KG BY LATER THIS AFTERNOON. STEERING FLOW IS GENERALLY LESS THAN 10KT. STORMS WILL INITIATE OVER HIGHER TERRAIN AND SLOWLY DEVELOP INTO LOWER ELEVATIONS LATER THIS AFTERNOON/EVENING. STILL A THREAT OF ISOLATED WIND/HAIL...HOWEVER WITH SOME DECREASE IN LAPSE RATES FROM THE PREVIOUS DAYS...ORGANIZED SEVERE THREAT IS NOT ANTICIPATED. ...INTERIOR NERN U.S... NEARLY FULL HEATING COUPLED WITH A MOIST AIR MASS WILL SUPPORT THUNDERSTORM DEVELOPMENT OVER HIGHER TERRAIN BY MID AFTERNOON FROM PA NEWD ACROSS NEW ENGLAND. WITH SHEAR GENERALLY LESS THAN 15KT...PULSE STORMS SHOULD BE THE PREDOMINANT MODE...WITH LOCAL GUSTY WINDS AND MARGINALLY SEVERE HAIL. ...SERN COASTAL AREAS... FULL HEATING AND A MOIST AIR MASS WILL LEAD TO MLCAPES TO ABOVE 2000 J/KG. SUFFICIENT SHEAR UP TO 20KT AND STEEP LOW LEVEL LAPSE RATES...SHOULD RESULT IN A FEW STRONG/SEVERE STORMS THIS AFTERNOON. PRIMARY AREA OF DEVELOPMENT SHOULD BE VICINITY OF SEA BREEZE FRONT COASTAL SC. ..HALES/JEWELL.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 19:59:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 15:59:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261955 SWODY1 SPC AC 261953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT WED JUL 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN LOWER MI INTO THE MID MS/LOWER MO RIVER VALLEYS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF ERN TX INTO WRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE CENTRAL HIGH PLAINS... ...CENTRAL GREAT LAKES ACROSS THE MID MS/LOWER MO RIVER VALLEYS... SHORTWAVE TROUGH IS WELL DEFINED ON WV IMAGERY THIS AFTERNOON MOVING ACROSS THE CENTRAL GREAT LAKES. SURFACE LOW IS EXPECTED TO REMAIN NORTH OF THE GREAT LAKES...WITH COLD FRONT /NOW EXTENDING SEWD FROM NERN WI INTO NRN IA/ SHIFTING SSEWD THROUGH THE REST OF THE PERIOD. CLOUDS HAVE REMAINED EXTENSIVE ACROSS MUCH OF LOWER MI TODAY ASSOCIATED WITH THIS FEATURE AND HAVE GREATLY LIMITED INSTABILITY AHEAD OF THE FRONT OVER MUCH OF THE CENTRAL GREAT LAKES. EXCEPTION IS WITHIN STRONG SUBSIDENT REGION OVER ERN/SRN WI AHEAD OF FRONT WHERE AN ISOLATED THUNDERSTORM MAY OCCUR. HOWEVER THIS SUBSIDENCE WILL LIKELY LIMIT CONVECTIVE POTENTIAL IN WAKE OF MID LEVEL TROUGH. APPEARS SEVERE THREAT MAY BE A BIT HIGHER FROM SERN LOWER MI INTO PORTIONS OF THE CENTRAL PLAINS WHERE RICH BOUNDARY LAYER MOISTURE IS SUPPORTING MODERATE TO STRONG INSTABILITY AHEAD OF MID LEVEL TROUGH AND ITS ASSOCIATED SURFACE COLD FRONT. THIS IS ESPECIALLY TRUE INTO THE LOWER/MID MO RIVER VALLEY WHERE MLCAPE IS NOW OVER 3000 J/KG. EFFECTIVE SHEAR FROM 25-35 KT ACROSS THE REGION WILL SUPPORT ORGANIZED LINES/CLUSTERS AND A RISK OF LARGE HAIL/DAMAGING WINDS AS STORMS INCREASE AND SPREAD ESEWD THROUGH THE EVENING. ...CENTRAL HIGH PLAINS... STORMS CONTINUE TO INCREASE OVER PORTIONS OF SRN WY AND NRN/CENTRAL CO AHEAD OF TAIL END OF SHORTWAVE TROUGH NOW OVERSPREADING THE NRN ROCKIES/HIGH PLAINS. ADDITIONAL INCREASING CU ARE EVIDENT ALONG STATIONARY SURFACE BOUNDARY INTO WRN NEB. 4-KM NMM WRF AND 18Z RUC CONTINUE TO DEVELOP SCATTERED CONVECTION AHEAD OF FEATURE MOVING ACROSS THE CENTRAL HIGH PLAINS THIS AFTERNOON/EVENING. GIVEN STRONG HEATING/STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR...STORMS MAY INCREASE/ORGANIZE THROUGH THE EARLY TO MID EVENING ESEWD ACROSS MUCH OF WRN NEB. ...SOUTHEAST TX/SWRN LA... APPEARS SEVERE THREAT HAS BEEN HINDERED TO THIS POINT BY EXTENSIVE CLOUDS/CONVECTION AND RESULTANT WEAK INSTABILITY. HOWEVER...LATEST RUC MAINTAINS FORECAST OF 30-40 KT SLY H85 LLJ THROUGH THE EVENING/OVERNIGHT AS TROPICAL IMPULSE SPREADS NWD ACROSS SERN TX. THIS MIGHT SUPPORT AN ISOLATED...BRIEF TORNADO AS 0-1 KM SHEAR HOLDS AROUND 20 KT /0-1 KM SRH OF 100 M2 S-2/ AND LCLS REMAIN QUITE LOW GIVEN MID 70F SURFACE DEW POINTS. ...SRN AZ INTO THE CO RIVER VALLEY... CONVECTIVE DEBRIS HAS ALL BUT CLEARED OVER MUCH OF THE REGION THIS AFTERNOON...AND WILL ALLOW MODERATE INSTABILITY TO AGAIN DEVELOP. THUNDERSTORMS CONTINUE TO INCREASE OVER HIGHER TERRAIN OVER SWRN NM AND FAR ERN AZ...AS WELL AS JUST NW OF LAS. EXPECT FURTHER DEVELOPMENT WILL OCCUR THIS AFTERNOON/EVENING. FLOW REMAINS RATHER WEAK...THOUGH 10-15 KT H7 WINDS SHOULD BE SUFFICIENT FOR SLOW MOVEMENT OVER LOWER ELEVATIONS THROUGH THE EVENING WITH THREATS OF HAIL AND BRIEF SEVERE GUSTS WITH STRONGER CORES. ...NORTHEAST... MID LEVEL LAPSE RATES AND DEEP LAYER SHEAR REMAIN QUITE WEAK ACROSS THIS REGION THIS AFTERNOON...DESPITE PRESENCE OF MODERATE INSTABILITY AND NEAR 70 SURFACE DEW POINTS. THEREFORE...EXPECT ANY SEVERE STORM WILL REMAIN BRIEF/MARGINAL INTO THE EARLY EVENING. ..EVANS.. 07/26/2006  From swody1 at goshenarc.org Thu Jul 27 01:04:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 21:04:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270100 SWODY1 SPC AC 270057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT WED JUL 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS EWD INTO THE LOWER OH VALLEY... ...MID MS AND LOWER OHIO VALLEYS... ALTHOUGH SHORTWAVE TROUGH HAS MOVED EAST OF THE AREA...CONVERGENCE AND HEATING WAS ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG SURFACE TROUGH THAT EXTENDED FROM SRN LOWER MI SWWD TO NEAR THE MO/IA BORDER. STRONGEST STORMS WERE LOCATED ACROSS CENTRAL IL WHERE MODERATE TO STRONG INSTABILITY WAS PRESENT WITH MARGINALLY FAVORABLE DEEP LAYER SHEAR FOR SUPERCELLS...REFERENCE WW 646. THESE STORMS SHOULD SPREAD ENEWD INTO IND THIS EVENING...THOUGH THE INSTABILITY IS WEAKER EAST OF IL AND THE SEVERE THREAT SHOULD GRADUALLY DIMINISH OVERNIGHT. AS LOW LEVEL JET STRENGTHENS FROM SERN OK INTO CENTRAL MO THIS EVENING...STORMS MAY DEVELOP IN CENTRAL MO ALONG A WEAK BOUNDARY SEPARATING DRIER BOUNDARY LAYER AIR IN SRN MO FROM A MOIST BOUNDARY LAYER IN NRN MO. ALTHOUGH WIND PROFILES ARE NOT PARTICULARLY IMPRESSIVE...MODERATE INSTABILITY MAY SUPPORT A FEW STORMS WITH MARGINALLY SEVERE HAIL/WIND. ...AZ... THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED ALONG THE RIM AND DESPITE ONLY 10-15 KT NLY MID LEVEL WINDS...STORMS MAY EVENTUALLY COLD POOL AND MOVE SSWWD TOWARD PRC AND WEST OF PHX LATE THIS EVENING. HOWEVER..STORM COMPLEX IS NOT AS IMPRESSIVE AS THIS SAME TIME LAST NIGHT AND SURFACE TEMPERATURES ARE ALSO ABOUT 5 DEGREES COOLER. ISOLATED WIND/HAIL THREAT MAY PERSIST THROUGH THE EVENING HOURS... BUT THINK SYSTEM WILL BE LESS ROBUST THAN LAST NIGHT. ...CENTRAL HIGH PLAINS... THUNDERSTORMS MOVING THROUGH WRN NEB/NERN CO WERE ASSOCIATED WITH A WEAK SHORTWAVE TROUGH MOVING THROUGH THE AREA. STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR MAY RESULT IN MARGINALLY SEVERE HAIL/WIND THE NEXT HOUR OR SO. HOWEVER...THE STORMS SHOULD WEAKEN QUICKLY THEREAFTER AS THE BOUNDARY LAYER COOLS/STABILIZES. ...ERN/LA... SEVERE THREAT WAS INHIBITED TODAY DUE TO EXTENSIVE CLOUDS/ PRECIPITATION AND RESULTANT WEAK INSTABILITY. MODELS MAINTAIN A FORECAST OF A 30-40 KT SLY LLJ OVERNIGHT AS UPPER LOW IN SERN TX LIFTS SLOWLY NWD. HOWEVER...THE DEEP UNIDIRECTIONAL SLY WINDS SUGGEST THE TORNADO THREAT IS LOW. ...OH... BAND OF STORMS ASSOCIATED WITH UPPER TROUGH WERE MOVING INTO CENTRAL OH THIS EVENING. A FEW HAIL/WIND EVENTS ARE POSSIBLE FOR THE NEXT 1 TO 2 HOURS...BUT STORMS SHOULD WEAKEN SHORTLY AS THE STORMS MOVE INTO A MORE STABLE ENVIRONMENT. ..IMY.. 07/27/2006  From swody1 at goshenarc.org Thu Jul 27 01:21:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 21:21:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270115 SWODY1 SPC AC 270113 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0813 PM CDT WED JUL 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS EWD INTO THE LOWER OH VALLEY... CORRECTED FOR TITLE IN 5TH PARAGRAPH ...MID MS AND LOWER OHIO VALLEYS... ALTHOUGH SHORTWAVE TROUGH HAS MOVED EAST OF THE AREA...CONVERGENCE AND HEATING WAS ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG SURFACE TROUGH THAT EXTENDED FROM SRN LOWER MI SWWD TO NEAR THE MO/IA BORDER. STRONGEST STORMS WERE LOCATED ACROSS CENTRAL IL WHERE MODERATE TO STRONG INSTABILITY WAS PRESENT WITH MARGINALLY FAVORABLE DEEP LAYER SHEAR FOR SUPERCELLS...REFERENCE WW 646. THESE STORMS SHOULD SPREAD ENEWD INTO IND THIS EVENING...THOUGH THE INSTABILITY IS WEAKER EAST OF IL AND THE SEVERE THREAT SHOULD GRADUALLY DIMINISH OVERNIGHT. AS LOW LEVEL JET STRENGTHENS FROM SERN OK INTO CENTRAL MO THIS EVENING...STORMS MAY DEVELOP IN CENTRAL MO ALONG A WEAK BOUNDARY SEPARATING DRIER BOUNDARY LAYER AIR IN SRN MO FROM A MOIST BOUNDARY LAYER IN NRN MO. ALTHOUGH WIND PROFILES ARE NOT PARTICULARLY IMPRESSIVE...MODERATE INSTABILITY MAY SUPPORT A FEW STORMS WITH MARGINALLY SEVERE HAIL/WIND. ...AZ... THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED ALONG THE RIM AND DESPITE ONLY 10-15 KT NLY MID LEVEL WINDS...STORMS MAY EVENTUALLY COLD POOL AND MOVE SSWWD TOWARD PRC AND WEST OF PHX LATE THIS EVENING. HOWEVER..STORM COMPLEX IS NOT AS IMPRESSIVE AS THIS SAME TIME LAST NIGHT AND SURFACE TEMPERATURES ARE ALSO ABOUT 5 DEGREES COOLER. ISOLATED WIND/HAIL THREAT MAY PERSIST THROUGH THE EVENING HOURS... BUT THINK SYSTEM WILL BE LESS ROBUST THAN LAST NIGHT. ...CENTRAL HIGH PLAINS... THUNDERSTORMS MOVING THROUGH WRN NEB/NERN CO WERE ASSOCIATED WITH A WEAK SHORTWAVE TROUGH MOVING THROUGH THE AREA. STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR MAY RESULT IN MARGINALLY SEVERE HAIL/WIND THE NEXT HOUR OR SO. HOWEVER...THE STORMS SHOULD WEAKEN QUICKLY THEREAFTER AS THE BOUNDARY LAYER COOLS/STABILIZES. ...ERN TX/LA... SEVERE THREAT WAS INHIBITED TODAY DUE TO EXTENSIVE CLOUDS/ PRECIPITATION AND RESULTANT WEAK INSTABILITY. MODELS MAINTAIN A FORECAST OF A 30-40 KT SLY LLJ OVERNIGHT AS UPPER LOW IN SERN TX LIFTS SLOWLY NWD. HOWEVER...THE DEEP UNIDIRECTIONAL SLY WINDS SUGGEST THE TORNADO THREAT IS LOW. ...OH... BAND OF STORMS ASSOCIATED WITH UPPER TROUGH WERE MOVING INTO CENTRAL OH THIS EVENING. A FEW HAIL/WIND EVENTS ARE POSSIBLE FOR THE NEXT 1 TO 2 HOURS...BUT STORMS SHOULD WEAKEN SHORTLY AS THE STORMS MOVE INTO A MORE STABLE ENVIRONMENT. ..IMY.. 07/27/2006  From swody1 at goshenarc.org Thu Jul 27 05:26:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 27 Jul 2006 01:26:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270522 SWODY1 SPC AC 270520 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1220 AM CDT THU JUL 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MID MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER NORTHERN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS IN AZ... ...SYNOPSIS... A SERIES OF WEAK UPPER IMPULSES WILL MOVE THROUGH A BROAD UPPER TROUGH EXTENDING FROM THE NRN ROCKIES SEWD INTO THE OH VALLEY AND THEN NEWD INTO NEW ENGLAND. A WEAK TROPICAL SYSTEM OVER ERN TX IS EXPECTED TO LIFT NNEWD DURING THE PERIOD AND EVENTUALLY BECOME ABSORBED INTO THE UPPER TROUGH ACROSS THE MID MS VALLEY. ...MID MS VALLEY REGION... DEVELOPMENT OF SEVERE CONVECTION ONCE AGAIN WILL BE PROBLEMATIC AS TIMING OF SHORTWAVE TROUGHS AND MARGINAL SHEAR EXISTS FOR SEVERE STORMS. CURRENTLY THINKING IS SHORTWAVE TROUGH...LOCATED IN THE WRN DAKOTAS...WILL MOVE THROUGH ERN IA AT PEAK HEATING. THE LIFT FROM THIS SYSTEM PLUS THE FORECAST OF A REMNANT FRONT/BOUNDARY STRETCHING FROM NRN MO EWD INTO NRN IND IS EXPECTED TO PROVIDE THE FOCUS FOR STRONG/SEVERE CONVECTIVE DEVELOPMENT. A VERY MOIST BOUNDARY LAYER AND TEMPERATURES WARMING TO AT LEAST 90F WILL RESULT IN A UNSTABLE AIR MASS OVER MUCH OF THIS REGION. THE AMOUNT OF INSTABILITY AND 25 KT EFFECTIVE SHEAR SHOULD BE SUFFICIENT FOR SEVERE MULTICELL CLUSTERS. THE STORMS WOULD LIKELY WEAKEN TO MOSTLY BELOW SEVERE CRITERIA BY MID EVENING SINCE THE STORMS WILL BE PRIMARILY THERMODYNAMICALLY DRIVEN. ...NRN NEW ENGLAND... PRONOUNCED SHORTWAVE TROUGH...CURRENTLY MOVING THROUGH THE ERN GREAT LAKES REGION...WILL MOVE ACROSS NRN NEW ENGLAND DURING THE HEAT OF THE DAY. MID LEVEL WINDS ARE FORECAST TO INCREASE TO NEAR 30 KT WITH UNIDIRECTIONAL SWLY WINDS ABOVE THE BOUNDARY LAYER. THIS SHOULD PROVIDE A FAVORABLE ENVIRONMENT FOR BANDS/LINES OF STORMS TO DEVELOP. ALTHOUGH THE INSTABILITY WILL NOT BE PARTICULARLY STRONG...MID LEVEL LAPSE RATES WILL BE STEEPER THAN NORMAL...AROUND 7.5 C/KM. THE SHEAR IN COMBINATION WITH THE LARGE SCALE FORCING AND STEEP LAPSE RATES SHOULD FAVOR A FEW SEVERE WIND AND HAIL EVENTS DURING THE AFTERNOON/EARLY EVENING HOURS. ..AZ... RICH LOW LEVEL MOISTURE WILL AGAIN BE IN PLACE OVER MUCH OF THE AREA THURSDAY...SUPPORTING MODERATE TO STRONG INSTABILITY. THE MID LEVEL NLY WINDS ARE FORECAST TO STRENGTHEN AS THE UPPER HIGH SHIFTS NWD THROUGH NV. A SHORTWAVE TROUGH IN ERN UT IS ALSO EXPECTED TO ROTATE AROUND THE HIGH AND INTO NERN AZ DURING THE AFTERNOON. THE STRONGER MID/HIGH LEVEL WINDS WILL HELP TO MOVE CONVECTION/CLOUDS SWD OUT OF THE STATE THIS MORNING. ALTHOUGH THE HEATING LIKELY WILL NOT BE AS STRONG AS THE PAST SEVERAL DAYS... ONCE THE STORMS DEVELOP OVER THE HIGHER TERRAIN...THE STRONGER WINDS/SHEAR SHOULD CARRY THEM SWD INTO THE DESERT FLOORS WITH A THREAT FOR SEVERE WINDS AND PERHAPS SOME HAIL. ...NRN OH/WRN NY... WRF MODEL SUGGESTS THAT THE LAKE BREEZE WILL BECOME CONVECTIVELY ACTIVE DURING THE AFTERNOON. THE DEEP LAYER SHEAR WILL BE MARGINAL FOR SEVERE...BUT UNDIRECTIONAL WLY WINDS AND MLCAPE VALUES FROM 1500-2000 J/KG WOULD SUPPORT STRONG WIND GUSTS. ...KS... MID/HIGH LEVEL MOISTURE FROM THE MONSOONAL FLOW WILL SPREAD NEWD ACROSS KS AND HELP IN THE INITIATION OF LATE AFTERNOON THUNDERSTORMS. HOT TEMPERATURES AND STEEP LOW LEVEL LAPSE RATES MAY SUPPORT SOME STRONG/SEVERE WIND GUSTS. ..IMY/TAYLOR.. 07/27/2006  From swody1 at goshenarc.org Fri Jul 28 06:14:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 02:14:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280614 SWODY1 SPC AC 280612 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0112 AM CDT FRI JUL 28 2006 VALID 281200Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS MID ATLANTIC...NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS WRN/NRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS UPPER MS VALLEY TO WRN LM... ...SYNOPSIS... PROGRESSIVE NRN STREAM FLOW WILL CONTINUE THROUGH PERIOD...FEATURING PRONOUNCED SHORTWAVE TROUGH NOW EVIDENT IN MOISTURE CHANNEL IMAGERY FROM LM SWWD ACROSS MO. THIS FEATURE IS FCST TO MOVE EWD ACROSS ERN GREAT LAKES...MID ATLANTIC AND NEW ENGLAND STATES THROUGH 29/00Z. MEANWHILE TROUGH NOW OVER NERN MB AND FAR NRN ONT SHOULD CONTINUE MOVING EWD OVER JAMES BAY REGION...WHILE ASSOCIATED LOW LEVEL COLD FRONT MOVES INTO NRN PLAINS. BY 29/06Z THIS FRONT SHOULD STALL INVOF ND/SD BORDER AS LEE CYCLONE INTENSIFIES OVER WRN SD. ANOTHER DIFFUSE FRONTAL ZONE WILL REMAIN QUASISTATIONARY FROM ERN NM ENEWD ACROSS OK AND OZARKS REGION...MODULATED ON MESOSCALE LEVEL BY NUMEROUS OUTFLOW BOUNDARIES. MEANWHILE...MID-UPPER LEVEL LOW -- WELL DEFINED IN MOISTURE CHANNEL IMAGERY ATTM OVER NWRN NM -- IS FCST TO DRIFT SWWD OVER ERN AZ....ENHANCING NELY GRADIENT FLOW AROUND RIM OF NV ANTICYCLONE. ...MID ATLANTIC...NEW ENGLAND... SCATTERED TSTMS ARE FCST TO DEVELOP IN FAVORABLY MOIST AIR MASS FROM LATE MORNING THROUGH AFTERNOON...ORGANIZING INTO ONE OR MORE BANDS/CLUSTERS WHILE MOVING EWD ACROSS REGION. MAIN THREAT WILL BE DAMAGING WINDS. HOWEVER...SUFFICIENT VEERING IS EVIDENT IN FCST HODOGRAPHS FROM ERN PA ACROSS SRN/CENTRAL NEW ENGLAND TO SUPPORT SUPERCELL MODE WITH ANY RELATIVELY DISCRETE CONVECTION. MAIN UNCERTAINTY ATTM IS STRENGTH OF DIABATIC HEATING IN ADVANCE OF CLOUD/PRECIP SHIELD ASSOCIATED WITH ONGOING MCS. THIS RENDERS PROGRESSIVELY MORE UNCERTAINTY WITH WWD EXTENT NOW EVIDENT FROM LE SWWD ACROSS NWRN OH AND INDIANA. VERTICAL WIND PROFILES AND LOW LEVEL SHEAR EACH ARE EXPECTED TO WEAKEN WITH SWWD EXTENT ACROSS APPALACHIANS AND OH VALLEY REGION...FAVORING MORE SPORADIC...PULSE/MULTICELL SEVERE THREAT AND LOWER PROBABILITIES. ...AZ... CLOUD COVER NOW EVIDENT OVER PORTIONS NRN/WRN AZ -- RESIDUE FROM EARLIER CONVECTION -- SHOULD ABATE ENOUGH BY UPCOMING AFTERNOON TO PERMIT STRONG INSOLATION ACROSS LARGE PORTION OF REGION...W OF APCHG MID/UPPER LEVEL PERTURBATION. SFC DEW POINTS REMAINING UPPER 60S TO LOW 70S F IN DESERTS AND NEAR 60 IN HIGHER ELEVATIONS WILL FURTHER CONTRIBUTE TO WEAK MID-LATE AFTERNOON CINH AND TSTM POTENTIAL. ATOP THAT INCREASINGLY UNSTABLE BOUNDARY LAYER...AFOREMENTIONED CORRIDOR OF ENHANCED MIDLEVEL NELYS WILL ENHANCE DEEP-LAYER SHEAR FAVORING SOME ORGANIZED SVR THREAT. POTENTIAL EXISTS FOR TSTMS TO FORM OVER HIGHER ELEVATIONS AND ORGANIZE INTO OUTFLOW DOMINANT MCS MOVING INTO WELL MIXED/STRONGLY HEATED BOUNDARY LAYERS OVER DESERTS. MAIN THREAT IS DAMAGING WIND...THOUGH ISOLATED HAIL MAY BE A CONCERN WHEN STORMS ARE STILL FAIRLY DISCRETE. FARTHER SE ACROSS SERN AND EXTREME E-CENTRAL AZ...AND SWRN NM...MORE UNCERTAINTIES EXIST REGARDING STRENGTH OF AFTERNOON DESTABILIZATION...IN WAKE OF MCS DURING DAY THURSDAY AND ANOTHER COMPLEX NOW MOVING SWWD ACROSS THAT AREA. FLOW ALOFT ALSO IS EXPECTED TO BE WEAKER AND LOSE ELY COMPONENT WITH SEWD GEOGRAPHIC EXTENT....INHIBITING BOTH VERTICAL SHEAR AND PROPAGATION POTENTIAL ONTO DESERTS FROM ERN PORTIONS MOGOLLON RIM. THEREFORE SVR PROBABILITIES ARE KEPT MRGL ATTM. ...UPPER MIDWEST... SCATTERED TSTMS SHOULD DEVELOP DURING AFTERNOON INTO EARLY EVENING HOURS...PERHAPS ORGANIZING INTO MCS WITH DAMAGING GUSTS AND LARGE HAIL POSSIBLE. NEARLY UNIDIRECTIONAL DEEP-LAYER WIND PROFILES ARE FCST...ALONG WITH MLCAPES SOMETIMES EXCEEDING 2500 J/KG. THIS SUPPORTS POTENTIAL FOR STRONG-SEVERE DOWNDRAFTS...GIVEN STRONG SFC HEATING AND FAVORABLE BOUNDARY LAYER MOISTURE EXPECTED. AFTER DARK...STRONG LOW LEVEL WAA AND AT LEAST MRGL MOISTURE WILL SUPPORT POTENTIAL FOR ELEVATED MCS FORMATION ACROSS PORTIONS ND/MN. STEEP LAPSE RATES AND FAVORABLE EFFECTIVE SHEARS WILL SUPPORT POTENTIAL FOR TSTMS TO PRODUCE ISOLATED LARGE HAIL. ...OZARKS TO NW TX... WIDELY SCATTERED TSTMS ARE EXPECTED TO DEVELOP AGAIN THIS AFTERNOON INVOF WEAK LOW LEVEL BAROCLINIC ZONE...ESPECIALLY ALONG OUTFLOW BOUNDARIES AND THEIR INTERSECTIONS. HOT...DEEPLY MIXED SUBCLOUD LAYERS WILL PROVIDE THREAT FOR A FEW DAMAGING WIND EVENTS WITH STRONGEST PULSE/MULTICELLULAR ACTIVITY. HOWEVER...ORGANIZED SVR IS NOT ANTICIPATED BECAUSE OF WEAK WINDS/SHEAR AND OUTFLOW-DOMINANT/SHORT-LIVED NATURE OF ANY GIVEN MULTICELL EVENT. SVR POTENTIAL WILL DIMINISH MARKEDLY AFTER SUNSET WHEN DIABATIC COOLING REMOVES SBCAPE. ..EDWARDS/TAYLOR.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 12:38:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 08:38:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281239 SWODY1 SPC AC 281237 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0737 AM CDT FRI JUL 28 2006 VALID 281300Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM SERN NY AND ERN PA INTO SRN NEW ENGLAND.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF NRN WI INTO SRN UPR MI.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF WRN AZ.... ...SYNOPSIS... WATER VAPOR IMAGERY SHOWS VERY WELL THE MID/UPPER LEVEL TROUGH MOVING EWD ACROSS ERN LOWER MI INTO THE MID MS VALLEY. THIS TROUGH IS EXPECTED TO CONTINUE MOVG EWD ACROSS THE LOWER GREAT LAKES TODAY AND NEW ENGLAND TONIGHT. MID LEVEL RIDGING IS ALSO INDICATED ACROSS THE NRN PLAINS. THIS WILL RESULT IN WNWLY FLOW ALOFT OVER THE UPPER GREAT LAKES THAT WILL BRING A WEAK FRONT SEWD INTO NRN WI THIS AFTERNOON. MEANWHILE...SUMMERTIME MID/UPPER LEVEL RIDGE WILL BE OVER THE CENTRAL INTERMOUNTAIN REGION TODAY...BUT ADVANCE INTO THE CENTRAL PLAINS TONIGHT AS WEAK INVERTED TROUGH MOVES WWD ACROSS NM/AZ. ...PARTS OF NY AND SRN NEW ENGLAND... EARLY VISIBLE SATELLITE IMAGES INDICATE PLENTY OF CLOUD COVER EAST OF MID/UPPER LEVEL TROUGH ACROSS NY STATE INTO PA AND WEST INTO OHIO. THIS WILL LIMIT AMOUNT OF INSTABILITY ACROSS NY INTO NEW ENGLAND...AND 06Z RUN OF THE NAM SUPPORTED THIS NOTION. 00Z RUN OF THE WRF INDICATED STRONG THUNDERSTORMS ACROSS THIS REGION THIS AFTERNOON...BUT WAS ALSO MORE UNSTABLE THAN THE NAM. POOR LAPSE RATES WERE EVIDENT IN BOTH NAM AND RUC MODELS WITH LOW/MID LEVEL LAPSE RATES JUST UNDER 6C/KM. WSWLY LOW LEVEL FLOW OF 30-35 KT COUPLED WITH WSWLY 50 KT MID LEVEL FLOW PROVIDES SOME SPEED SHEAR FOR STRONG THUNDERSTORMS AHEAD OF THE ADVANCING TROUGH...BUT LITTLE IN THE WAY OF DIRECTIONAL SHEAR. FORECAST SOUNDINGS DO SHOW SOME STEEPER LAPSE RATES IN THE LOWEST 3KM ABOVE THE SFC INDICATING THAT STORMS MOVING INTO SERN NY AND SRN NEW ENGLAND WILL HAVE THE POTENTIAL FOR STRONG WIND GUSTS LATER THIS MORNING AND THIS AFTERNOON. BUT...GIVEN THE OVERALL LIMITED POTENTIAL WITH MOIST LAPSE RATES AND LIMITED INSTABILITY...HAVE LOWERED PROBABILITIES DOWNWARD...AND DIMINISHED SIZE OF SLGT RISK AREA TO SERN NY STATE AND ERN PA EWD S OF THE NRN MA BORDER. ...PARTS OF NRN AND WRN WI INTO THE U.P. OF MI... 00Z WRF MODELS SHOWS STRONG SIGNALS OF POTENTIAL LINE OF STRONG/SEVERE THUNDERSTORMS MOVING SEWD ACROSS NWRN...N CENTRAL AND NERN WI THIS AFTERNOON. FRONTAL BOUNDARY ACROSS NWRN MN THIS MORNING WILL TRACK SEWD AS WNWLY FLOW DEVELOPS DUE TO MINOR RIDGING FARTHER W OVER THE NRN HIGH PLAINS. THIS BOUNDARY WILL MOVE INTO AREAS WHERE IT IS POTENTIALLY UNSTABLE WITH CAPES BETWEEN 1000 AND 1500 J/KG AND MID LEVEL LAPSE RATES ARE AROUND 7C/KM. THUS...SOME SEVERE THUNDERSTORMS ARE POSSIBLE LATER TODAY AND EARLY TONIGHT ACROSS NRN WI INTO S CENTRAL UPR MI WITH MAIN THREAT BEING DAMAGING WINDS. MODELS INDICATE THE POTENTIAL FOR SOME THUNDERSTORMS LATER TONIGHT ACROSS IN WEAK WARM ADVECTION REGIME OVER N CENTRAL MN AS SWLY LOW LEVEL JET DEVELOPS OVER CENTRAL SD INTO W CENTRAL MN. ISOLATED STRONG THUNDERSTORMS ARE POSSIBLE IN ASSOCIATION WITH WEAK MCS DEVELOPING IN EXIT REGION OF LOW LEVEL JET. ...PARTS OF AZ... WEAK MID/UPPER LEVEL INVERTED TROUGH IS FORECAST TO MOVE WWD FROM WRN NM THIS MORNING INTO CENTRAL AND WRN SECTIONS OF AZ LATE TONIGHT. LATEST SURFACE ANALYSIS SHOWS BAND OF MID 60S TO LOW 70 DEW POINTS ACROSS S CENTRAL AND WRN AZ THIS MORNING. THE MODELS DESTABILIZE THE AIR MASS THIS AFTERNOON WHEN MIXED LAYER CAPE REACHES BETWEEN 1000 AND 1500 J/KG. WITH LOW LEVEL LAPSE RATES AROUND 7C/KM AND DCAPE JUST OVER 1100 J/KG...LOOK LIKE THUNDERSTORM ACTIVITY WILL CARRY THE POTENTIAL FOR DOWNBURST WINDS THIS AFTERNOON AND EARLY TONIGHT. ...PARTS OF OK... SEVERAL WEAK BOUNDARIES REMAIN OVER WRN AND NRN OK INTO SWRN MO IN RESPONSE TO HIGH-BASED THUNDERSTORM ACTIVITY ON THURSDAY. DAYTIME HEATING SHOULD ONCE AGAIN FAVOR AIR MASS TYPE THUNDERSTORMS LATE THIS AFTERNOON AND EARLY EVENING ACROSS NRN OK INTO SWRN MO AS AIR MASS WILL BECOME VERY UNSTABLE WITH MLCAPES JUST BELOW 2700 J/KG AND MID LEVEL LAPSE RATES NEAR 7C/KM. THUS...MUCH OF THE ACTIVITY SHOULD REMAIN BELOW SEVERE LEVELS WITH STRONG GUSTY WINDS ARE POSSIBLE ACROSS AREA. ..MCCARTHY.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 16:30:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 12:30:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281630 SWODY1 SPC AC 281628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT FRI JUL 28 2006 VALID 281630Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MID ATLANTIC INTO THE SRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A PART OF THE NRN PLAINS INTO THE NRN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ... ...MID ATLANTIC INTO SRN NEW ENGLAND... ACTIVE DAY FOR THUNDERSTORMS EXPECTED ACROSS THIS REGION AS SLOW MOVING MID LEVEL TROUGH AND ACCOMPANYING 40+ KT MID LEVEL JET /30+ KT WSWLY LLJ/ OVERSPREAD THE NORTHEAST. AIR MASS REMAINS QUITE MOIST WITH SURFACE DEW POINTS WELL INTO THE 70S AHEAD OF THIS FEATURE...WHICH WILL SUPPORT A VERY WARM/HUMID WARM SECTOR AS AFTERNOON HIGHS REACH INTO AT LEAST THE UPPER 80S/LOWER 90S. DESPITE LARGE LOW LEVEL THETA-E VALUES IN PLACE...WEAK LAPSE RATES / H7 TO H5 LAPSE RATES AOB 6 C KM-1 / WILL LIMIT AVAILABLE CAPE. REGARDLESS...MLCAPE SHOULD EXCEED 2000 J/KG ACROSS THE MID ATLANTIC AND 1500 J/KG INTO SRN NEW ENGLAND BY THE MID AFTERNOON. DEEP LAYER SHEAR FROM 30-40 KT WILL BE SUPPORTIVE OF ORGANIZATION INTO LINES/CLUSTERS. PRIMARY NEGATIVES FOR SUSTAINED OR MORE WIDESPREAD SEVERE WILL BE THE LIMITED LAPSE RATES AND RATHER WEAK LOW LEVEL CONVERGENCE ACROSS THE REGION. HOWEVER...POTENTIAL FOR STORM-SCALE ORGANIZATION AND AMOUNT INSTABILITY...ALONG WITH STEEPENING LOW LEVEL LAPSE RATES...SHOULD SUPPORT DAMAGING WINDS THIS AFTERNOON/EVENING. IN ADDITION...PW/S AROUND 2 INCHES AND RICH LOW LEVEL MOISTURE SOURCE WILL ENHANCE HEAVY RAINFALL POTENTIAL AS THUNDERSTORMS INCREASE THROUGH THE AFTERNOON AND SPREAD EWD OFF THE COAST BY THE EARLY TO MID EVENING /REFERENCE LATEST QPF GUIDANCE FROM HPC/. ...NRN PLAINS INTO THE NRN MS RIVER VALLEY AND NRN GREAT LAKES... MODELS STILL IN AGREEMENT IN INCREASING THUNDERSTORMS NEAR SURFACE COLD FRONT NOW EXTENDING ACROSS NRN MN AS IT SAGS SSEWD INTO NRN WI WRN U.P. OF MI THIS AFTERNOON. WARM SECTOR WILL REMAIN VERY MOIST WITH 70+F SURFACE DEW POINTS ALREADY IN PLACE OVER NRN MI/NRN WI. MODIFIED 12Z SOUNDINGS AT MPX AND GRB AND RUC FORECAST SOUNDINGS ACCOUNTING FOR MID/UPPER 90F SURFACE TEMPERATURES AND DEW POINTS AROUND 70F INDICATE MLCAPE WILL EXCEED 2500 J/KG OVER MUCH OF THIS REGION WITH LITTLE OR NO MLCIN BY 21Z. IN ADDITION...THE 12Z SOUNDING AT INL INDICATES 40 KT OF FLOW AROUND 3 KM WHICH IS FORECAST TO OVERSPREAD THE NRN GREAT LAKES THROUGH THE DAY. AS CAP WEAKENS...SURFACE FRONT SHOULD SUPPORT INCREASED THUNDERSTORM DEVELOPMENT FROM PORTIONS OF NRN/CENTRAL MN ACROSS NRN WI INTO THE WRN U.P. OF MI. DEEP LAYER SHEAR FROM 25-35 KT IS FORECAST TO BE MARGINAL FOR SUPERCELLS...BUT MORE THAN ADEQUATE FOR LINES/CLUSTERS GIVEN EXTREME INSTABILITY. DAMAGING WINDS WILL LIKELY BE PRIMARY SEVERE THREAT AS STORMS SHIFT SEWD THROUGH THE EVENING...THOUGH AN ISOLATED TORNADO THREAT MAY ALSO ACCOMPANY ANY SUSTAINED SUPERCELL STRUCTURE ESPECIALLY AS WLY LLJ INCREASES EARLY THIS EVENING. SEVERE THREAT SHOULD THEN SHIFT NWWD INTO ND ALONG NOSE OF A SLY LLJ...WHICH THE VEERS TO MORE SWLY LATER TONIGHT AHEAD OF SHORTWAVE TROUGH NOW SKIRTING NWRN MT. THIS SYSTEM WILL LIKELY RIDE EWD ACROSS ND ATOP LARGER UPPER RIDGE AND TURN SEWD INTO NRN MN BY THE END OF THE PERIOD. ELEVATED STORMS WILL LIKELY DEVELOP AFTER DARK INTO ND ALONG NOSE OF INCREASING LLJ ALONG AND NORTH OF SURFACE COLD FRONT EXPECTED TO STALL E-W NEAR THE SD-ND BORDER. VERY STEEP MID LEVEL LAPSE RATES...FEED OF ABUNDANT LOW LEVEL MOISTURE AND STRONG CLOUD-LAYER SHEAR SUGGEST ACTIVITY WILL BECOME INCREASINGLY ORGANIZED/INTENSE AFTER 03Z AND BUILD UPSCALE AS AN MCS ACROSS ERN ND INTO NWRN MN LATER TONIGHT. WARM MID LEVEL AIR MASS MAY ACT TO HINDER HAIL GROWTH...THOUGH LARGE HAIL WILL LIKELY ACCOMPANY STRONGER CORES GIVEN EFFECTIVE SHEAR AROUND 50 KT AND LIKELIHOOD OF ELEVATED SUPERCELLS. OVERALL SETUP WILL BECOME INCREASINGLY FAVORABLE FOR SEVERE MCS DEVELOPMENT...POSSIBLY IN THE FORM OF A BOW ECHO SYSTEM...ESPECIALLY IF STORMS CAN ROOT INTO SHALLOWER STABLE LAYER NEAR THE SURFACE FRONT LATER TONIGHT WHICH WILL CONTINUE INTO THE DAY 2 FORECAST PERIOD. ...AZ... WELL DEFINED MID/UPPER LEVEL INVERTED TROUGH AND ASSOCIATED LOW CENTER WILL CONTINUE A SLOW MOTION WSWWD INTO WRN AZ TODAY AND INTO CENTRAL AZ LATER TONIGHT. AIR MASS REMAINS QUITE MOIST WITH LATEST SURFACE ANALYSIS INDICATING MID 60S TO LOW 70 DEW POINTS IN PLACE ACROSS S CENTRAL AND WRN AZ THIS MORNING. IN ADDITION...MID LEVEL CLOUDS HAVE ALL BUT CLEARED MUCH OF CENTRAL AZ THIS MORNING WHICH WILL ALLOW A MODERATE TO STRONGLY UNSTABLE AIR MASS TO DEVELOP AHEAD OF THIS SYSTEM. RUC FORECAST SOUNDINGS INDICATE MLCAPE WILL LIKELY EXCEED 2500-3000 J/KG OVER LOWER ELEVATIONS GIVEN LOWER 70F SURFACE DEW POINTS AND AFTERNOON HIGHS WELL INTO THE 90S. AS LARGE SCALE ASCENT INCREASES...STORMS WILL LIKELY BECOME WIDESPREAD OVER MUCH OF AZ TODAY AND CONTINUE WELL INTO THE NIGHT. APPEARS DAMAGING WINDS AND VERY HEAVY RAINFALL...ALONG WITH SOME HAIL...WILL ACCOMPANY THIS ACTIVITY. ..EVANS/GUYER.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 20:16:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 16:16:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 282014 SWODY1 SPC AC 282012 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0312 PM CDT FRI JUL 28 2006 VALID 282000Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SRN NEW ENGLAND TO THE MID ATLANTIC REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A PART OF THE NRN PLAINS INTO THE NRN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ... ...MID ATLANTIC INTO SRN NEW ENGLAND... STRONG FORCING FOR ASCENT AHEAD OF SHORT WAVE TROUGH...NOW LOCATED FROM SRN QUEBEC TO THE CENTRAL APPALACHIANS...WILL MAINTAIN LINE OF THUNDERSTORMS EXPECTED TO MOVE EWD ACROSS SRN NEW ENGLAND AND THE REMAINDER OF THE MID ATLANTIC REGION INTO EARLY-MID EVENING. MODERATE INSTABILITY EAST OF ONGOING LINE OF STORMS COMBINED WITH STRONG DEEP LAYER SHEAR WILL CONTINUE TO SUPPORT ORGANIZED SEVERE STORMS WITH DAMAGING WINDS BEING THE PRIMARY THREAT INTO THE EVENING. ...NRN PLAINS INTO THE NRN MS VALLEY AND NRN GREAT LAKES... EARLY AFTERNOON SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING FROM NERN MN SWWD TO ALONG THE ND/SD BORDER...WITH A PRE-FRONTAL TROUGH HAVING MOVED INTO THE WRN U.P. OF MI AND NWRN WI/PARTS OF EAST CENTRAL MN. COLD FRONT WILL CONTINUE TO MOVE SWD AND SHOULD OVERTAKE THE PRE-FRONTAL TROUGH BY THIS EVENING. STRONG SURFACE HEATING ALONG/S OF THESE BOUNDARIES WITHIN VERY MOIST AIR MASS HAS ALLOWED AIR MASS TO BECOME VERY UNSTABLE ACROSS THE SRN THREE QUARTERS OF MN WITH AN AXIS OF MODERATE INSTABILITY EXTENDING EWD ALONG THE PRE-FRONTAL TROUGH. THE COMBINATION OF THE SURFACE HEATING AND ASCENT WITHIN THE RIGHT ENTRANCE REGION OF A 50 KT NWLY MID LEVEL JET...NOW LOCATED OVER NRN MN...ARE EXPECTED TO AID IN FURTHER WEAKENING OF INHIBITION. THUS...THUNDERSTORMS SHOULD CONTINUE TO DEVELOP WWD ALONG THE PRE-FRONTAL TROUGH...AND ALSO ALONG THE COLD FRONT AS THIS BOUNDARY MOVES SWD INTO CENTRAL MN/NRN WI AND THE U.P. OF MI. OBJECTIVE ANALYSES INDICATED EFFECTIVE BULK SHEAR VALUES HAVE INCREASED SUPPORTING ORGANIZED SEVERE STORMS WITH A FEW SUPERCELLS POSSIBLE. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREATS. HOWEVER...GIVEN MOIST BOUNDARY LAYER COMBINED WITH AN INCREASING SWLY LLJ EXTENDING INTO EAST CENTRAL MN/NRN WI BY EARLY EVENING...LOW LEVEL SHEAR IS EXPECTED TO INCREASE POTENTIALLY SUPPORTING AN ISOLATED TORNADO OR TWO. THIS LLJ WILL VEER TO WLY OVERNIGHT AND SHOULD MAINTAIN A CLUSTER OF STORMS SPREADING EWD TOWARD NRN LOWER MI/ERN U.P. OF MI. WEAKER INSTABILITY AHEAD OF THIS OVERNIGHT ACTIVITY SHOULD LIMIT THE ERN EXTENT OF SEVERE STORMS. BY LATE EVENING...SEVERE THREAT IS EXPECTED TO SHIFT WNWWD INTO ND/ NRN SD AS WAA INCREASES NORTH OF SURFACE FRONT AND ALONG NOSE OF STRENGTHENING NRN PLAINS SLY LLJ. THIS LLJ IS EXPECTED TO STRENGTHEN IN RESPONSE TO A SHORT WAVE TROUGH...NOW LOCATED OVER NERN MT/SRN SASKATCHEWAN...RIDING THE TOP OF THE RIDGE ACROSS SRN CANADA/ND TOWARD NRN MN. SUFFICIENT INFLOW OF MODERATE ELEVATED INSTABILITY AND 50-60 KT OF EFFECTIVE BULK SHEAR SUGGEST LIKELIHOOD FOR MCS DEVELOPMENT WITH EMBEDDED ELEVATED SUPERCELLS PRODUCING LARGE HAIL. THE LLJ SHOULD VEER TO SWLY ALLOWING THE MCS TO MOVE ESEWD INTO PARTS OF NRN/CENTRAL MN BY 12Z SATURDAY. DAMAGING WINDS MAY BECOME A THREAT IF STORMS CAN ROOT INTO SHALLOWER STABLE LAYER NEAR THE SURFACE LATER TONIGHT WHICH WILL CONTINUE INTO THE DAY 2 FORECAST PERIOD. ...AZ... WELL DEFINED MID/UPPER LEVEL CIRCULATION...CURRENTLY CENTERED ALONG AZ/NM BORDER...WILL CONTINUE TO PROGRESS SLOWLY SWWD THIS FORECAST PERIOD. ASCENT AHEAD OF THIS FEATURE AND SURFACE HEATING WILL SUPPORT ADDITIONAL THUNDERSTORM DEVELOPMENT ACROSS THE HIGHER TERRAIN OF CENTRAL/NWRN AZ INTO SWRN UT/SRN NV. NLY STEERING FLOW SUGGESTS STORMS ARE EXPECTED TO MOVE/PROPAGATE SWD TOWARD THE LOWER ELEVATIONS...WITH DAMAGING WINDS POSSIBLE. IN ADDITION... 25-30 KT OF DEEP LAYER SHEAR COMBINED WITH MODERATE INSTABILITY WILL SUPPORT A FEW SUPERCELLS PRODUCING LARGE HAIL AND STRONG WIND GUSTS. ..PETERS.. 07/28/2006  From swody1 at goshenarc.org Sat Jul 29 01:05:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 21:05:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290105 SWODY1 SPC AC 290103 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0803 PM CDT FRI JUL 28 2006 VALID 290100Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS SWRN CONUS... ...SYNOPSIS... UPPER AIR PATTERN IS CHARACTERIZED BY PROGRESSIVE NRN STREAM FLOW BELT...DOWNSTREAM FROM STRONG TROUGH LOCATED OFF BC COAST. SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER WRN NEW ENGLAND -- WILL MOVE OFFSHORE TONIGHT. RELATED SFC TROUGH AND COLLOCATED MCS ALREADY HAS WEAKENED AND MOVED LARGELY OFFSHORE...DROPPING SVR POTENTIAL OVER NERN CONUS. FARTHER W...WELL-DEFINED SFC COLD FRONT WILL CONTINUE MOVING SEWD FROM ONT AND LS ACROSS NERN MN...REMAINDER LS...AND UPPER MI THROUGH REMAINDER PERIOD. WRN PORTION OF THIS FRONT -- NOW ANALYZED INVOF ND/SD BORDER -- SHOULD REMAIN STATIONARY OR DRIFT SLIGHTLY NWD E OF COMBINED LEE/FRONTAL-WAVE CYCLONE THAT IS ANALYZED ACROSS NWRN SD. MEANWHILE...MID-UPPER LEVEL LOW REMAINS WELL DEFINED IN MOISTURE CHANNEL IMAGERY OVER AZ/NM BORDER...WITH WEAK WWD TO SWWD DRIFT ANTICIPATED THROUGH TONIGHT. ...AZ... SCATTERED-NUMEROUS TSTMS HAVE DEVELOPED FROM SWRN UT SSEWD ACROSS W-CENTRAL AZ...SOME OF WHICH HAVE PRODUCED LARGE HAIL. REF SPC WW 651 AND RELATED MESOSCALE DISCUSSION FOR NEAR-TERM DETAILS. WELL MIXED BOUNDARY LAYERS WILL SUPPORT POTENTIAL FOR EVOLUTION INTO FORWARD-PROPAGATING MCS. ASSOCIATED DAMAGING WIND POTENTIAL MAY INCREASE WSWWD ACROSS LOWER ELEVATIONS THROUGH REMAINDER EVENING AS ACTIVITY PROPAGATES THAT WAY...WITH HELP FROM MIDLEVEL NELYS APPARENT IN VWP FROM FLG/PHX. BROAD AREA OF FAVORABLE INSTABILITY -- WITH MLCAPES 1500-3000 J/KG -- REMAINS ACROSS SWATH FROM SWRN AZ NWWD ACROSS CO RIVER VALLEY REGION AHEAD OF THIS ACTIVITY...IN PROSPECTIVE INFLOW REGION. ...UPPER MIDWEST... REF SPC WW 650 AND ACCOMPANYING MESOSCALE DISCUSSIONS FOR NOWCAST DETAILS REGARDING SVR THREAT WITH ONGOING ACTIVITY OVER NRN WI AND UPPER MI. AS WRN GREAT LAKES AREA OF CONVECTION GRADUALLY WEAKENS...GREATEST SVR POTENTIAL IS FCST TO TRANSFER WWD TO ND AND PERHAPS EXTREME NRN SD NEXT FEW HOURS. SVR TSTMS MAY EVOLVE FROM ONGOING HIGH-BASED CONVECTION INVOF ND/SD BORDER...IN ENVIRONMENT OF FAVORABLE DEEP-LAYER SHEAR. INTENSELY HEATED/MIXED SUBCLOUD LAYERS WILL FAVOR MAINTENANCE OF STRONG-SVR DOWNDRAFTS TO SFC...AS WELL AS ANY LARGE HAIL THAT MAY BE GENERATED ALOFT. 00Z BIS RAOB SHOWS STRONG CAP N OF SFC FRONT BUT ALSO STRONG LOW LEVEL WAA. THIS PROCESS SHOULD CONTINUE THROUGH REMAINDER TONIGHT OVER MUCH OF CENTRAL/ERN ND...SHIFTING INTO W-CENTRAL/NWRN MN...WITH ENOUGH MOISTENING THROUGH AROUND 06Z TO SUPPORT PARCELS ISENTROPICALLY RAISED TO LFC. THIS PROCESS...COMBINED WITH POTENTIAL FOR DAMAGING WIND PRODUCING MCS EVOLVING FROM CURRENT SFC-BASED DEVELOPMENT FARTHER W...INDICATES RISK FOR SVR SHOULD BE MAINTAINED OVER THIS REGION FOR OVERNIGHT HOURS. ONE OR TWO MCS SHOULD EVOLVE OVERNIGHT...MOVING GENERALLY ESEWD ACROSS MN AND CARRYING SVR POTENTIAL OVER INTO DAY-2 PERIOD. ..EDWARDS.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 06:05:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 02:05:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290605 SWODY1 SPC AC 290603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT SAT JUL 29 2006 VALID 291200Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN ND TO LOWER MI... ...SYNOPSIS... NRN STREAM PATTERN WILL BE CHARACTERIZED BY MEAN RIDGING OVER CENTRAL/NRN PLAINS...AND HEIGHT FALLS OVER PACIFIC NW LATE IN PERIOD AHEAD OF PROGRESSIVE TROUGH NOW OFFSHORE BC. MIDDLE/UPPER LEVEL LOW -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY INVOF AZ/NM BORDER -- IS EXPECTED TO WEAKEN GRADUALLY. PART OF ITS VORTICITY FIELD MAY SHIFT NEWD ACROSS SRN CO AGAIN...WITH THE REST WEAKENING OVER AZ. AT SFC...PRONOUNCED FRONTAL ZONE WILL EXTEND FROM COMBINED LEE-SIDE/FRONTAL-WAVE LOW OVER SD...EWD ACROSS MN THEN ESEWD OVER LOWER MI. FRONT WILL BE SHIFTED SWD ON MESOSCALE BY MCS OUTFLOWS. ...UPPER GREAT LAKES...UPPER MIDWEST... TWO PRINCIPAL SVR EPISODES ARE POSSIBLE ACROSS THIS REGION...INITIALLY WITH EWD EXTENSION OF MCS NOW OVER ND/NERN SD...AND SUBSEQUENTLY WITH AFTERNOON/EVENING DEVELOPMENT ALONG AND N OF FRONTAL/OUTFLOW BOUNDARY LEFT BEHIND BY FIRST COMPLEX. TO SOME EXTENT...LARGEST SVR PROBABILITIES REPRESENT SPATIAL OVERLAY OF BOTH. ONGOING STRONG-SVR TSTMS ACROSS PORTIONS WI...AS OF 05Z...CONTINUE TO MOVE SFC BAROCLINIC ZONE FRONT SWD ACROSS THAT REGION. THIS PROCESS WILL BE REINFORCED BY MCS NOW PRIMARILY OVER ND. MEANWHILE COMBINATION OF CLOUD DEBRIS...AREAS OF PRECIP AND LACK OF SUBSTANTIAL ISALLOBARIC FORCING WILL KEEP FRONTAL ZONE ALONG OR JUST S OF PRESENT POSITION ACROSS MI. THEREFORE FAVORABLE MCS CORRIDOR SHOULD BE FROM E-CENTRAL/NERN MN ESEWD ACROSS CENTRAL WI AND CENTRAL LOWER MI INITIALLY...AS BOUNDARY LAYER HEATS ACROSS THIS REGION AND AHEAD OF REMAINS OF CURRENT DAKOTAS COMPLEX. DAMAGING GUSTS AND ISOLATED HAIL ARE POSSIBLE. FARTHER W...RELATIVELY STEEP LAPSE RATES ALOFT...VIGOROUS SFC HEATING AND LIFT INVOF BOUNDARY SHOULD OVERCOME STRONG CINH...LEADING TO AFTERNOON/EVENING INITIATION FROM ERN ND ACROSS CENTRAL MN. VERTICAL SHEAR PROFILES WILL BE FAVORABLE FOR SUPERCELLS AND BOW ECHOES IN BOTH REGIMES...ESPECIALLY WITHIN SFC FRONTAL ZONE WHERE BULK SHEAR...VORTICITY...STORM-RELATIVE INFLOW AND SRH ALL SHOULD BE MAXIMIZED. GREATEST AFTERNOON MLCAPES...PERHAPS REACHING 3000-4000 J/KG RANGE...ARE EXPECTED OVER WRN REGIME. EVOLUTION OF SECOND MCS WITH DAMAGING GUSTS AND LARGE HAIL IS POSSIBLE ESEWD ACROSS MN...AND OVERNIGHT INTO WI. ...LOWER GREAT LAKES... WIDELY SCATTERED TO ISOLATED TSTMS MAY DEVELOP ACROSS NRN OH/NWRN PA/WRN NY REGION DURING AFTERNOON...AMIDST STRONG SFC HEATING AND FAVORABLE MOISTURE...WITH LOCALIZED/MRGL SVR POTENTIAL. BETTER ORGANIZED BUT MORE CONDITIONAL SVR THREAT EXISTS IN ASSOCIATION WITH POTENTIAL MCS MOTION INTO THIS AREA...FROM LOWER MI AND/OR SRN ONT. THIS POTENTIAL ALSO MAY BE SUPPORTED BY ANY MCV OR CONVECTIVELY ENHANCED/PRE-EXISTING PERTURBATIONS SUCH AS THAT EVIDENT NOW OVER NWRN MN/NERN SD. SOME PART OF THIS AREA MAY BE ADDED TO CATEGORICAL SLGT RISK AS DIURNAL DESTABILIZATION PATTERNS AND UPSTREAM CONVECTIVE TRENDS WARRANT. ...SWRN CONUS... ISOLATED STRONG-SVR TSTMS MAY DEVELOP THIS AFTERNOON/EVENING OVER THIS REGION...HOWEVER BOTH KINEMATIC AND THERMODYNAMIC PROFILES APPEAR LESS FAVORABLE FOR ORGANIZED SVR EVENT OVER REGION AS A WHOLE. CLOUD DEBRIS AND DEEP-LAYER LAPSE RATE STABILIZATION BY ONGOING ACTIVITY WILL DELAY AIR MASS RECOVERY ESPECIALLY OVER WRN/NRN AZ. POCKETS OF FAVORABLE DESTABILIZATION ARE POSSIBLE ACROSS THIS AREA DURING MID-LATE AFTERNOON...RESULTING IN LOCALIZED STRONG HEATING OF HIGHER TERRAIN AND DEEPLY MIXED BOUNDARY LAYERS ACROSS DESERT AREAS. AREA OF MIDLEVEL NELY FLOW SHOULD WEAKEN...AS WELL AS SHRINK IN BOTH HORIZONTAL AND VERTICAL EXTENT...AS RELATED MID/UPPER LEVEL LOW BECOMES MORE POORLY DEFINED. STILL...A FEW TSTMS MAY FORM OVER HIGHER ELEVATIONS OF NRN AZ AND MOVE SWWD WITH DAMAGING GUSTS BEING MAIN CONCERN. ACROSS SERN AZ/SWRN NM...MORE PROLONGED HEATING IS POSSIBLE...BUT DEEP-LAYER FLOW WILL BE WEAKER WITH MORE WLY COMPONENT ALOFT. SVR POTENTIAL SHOULD BE RATHER SPORADIC AND DISORGANIZED. ...SERN CONUS... SCATTERED TSTMS IN CLUSTERS...WITH ISOLATED DAMAGING WIND OR MARGINALLY SVR HAIL...WILL BE POSSIBLE OVER VERY BROAD SWATH OF SERN STATES. POTENTIAL WILL BE CONCENTRATED AROUND SEA BREEZE FRONTS...MESOSCALE DIFFERENTIAL HEATING BOUNDARIES RELATED TO PRECURSORY CLOUD/PRECIP PATTERNS...AND OUTFLOW INTERSECTIONS. BUOYANCY MAY BE MAXIMIZED ACROSS ERN PIEDMONT/COASTAL PLAIN OF AL...GA AND CAROLINAS. IN THAT CORRIDOR...SUCH BOUNDARIES WILL BE MOST COMMON...ALONG WITH SFC DEW POINTS IN 70S F AND STRONG AFTERNOON HEATING IN RELATIVELY CLOUD-FREE AREAS. MAIN MODE WILL BE MULTICELLULAR AND PULSE IN NATURE BECAUSE OF WEAK DEEP-LAYER FLOW AND LACK OF VERTICAL SHEAR. ...NRN HIGH PLAINS... ELY SFC FLOW COMPONENT N OF SFC FRONT...AND NW OF SFC LOW...WILL ACT TO TRANSPORT MOISTURE INTO ERN MT...AS WELL AS TO ENHANCE DEEP-LAYER SHEAR AND WEAKLY AID IN LOW LEVEL ASCENT. THIS WILL LEAD TO POTENTIAL FOR WIDELY SCATTERED TSTMS BY MID-LATE AFTERNOON AS SFC HEATING AND UPSLOPE LIFT WEAKEN SBCINH. ADVECTION SHOULD YIELD ENOUGH BOUNDARY LAYER MOISTURE TO YIELD FAVORABLE MLCAPES -- 1000-1500 J/KG BASED ON MODIFIED WRF SOUNDINGS -- HOWEVER SUBCLOUD LAYERS STILL WILL BE RELATIVELY DRY AND WELL-MIXED. THIS FAVORS POTENTIAL FOR DAMAGING GUSTS AND HAIL WITH MOST INTENSE CELLS. ..EDWARDS/GRAMS.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 12:45:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 08:45:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291243 SWODY1 SPC AC 291242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT SAT JUL 29 2006 VALID 291300Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATER THIS AFTERNOON AND TONIGHT ACROSS THE UPPER MIDWEST AND UPPER GREAT LAKES.... ...SYNOPSIS... LARGE MID/UPPER LEVEL RIDGE IS RE-ESTABLISHING ITSELF FROM THE CENTRAL INTERMOUNTAIN REGION EWD ACROSS MUCH OF THE PLAINS AND MS VALLEY INTO THE GULF COAST STATES. THIS PLACES MAIN BAND OF WESTERLIES FROM THE PACIFIC NORTHWEST STATES NEWD INTO THE NRN ROCKIES AND EXTREME NRN PLAINS THEN SEWD ACROSS THE GREAT LAKES AND NEW ENGLAND. SEVERAL MINOR SHORTWAVE TROUGHS WILL BE EMBEDDED WITHIN THE FLOW FROM MT ENEWD OVER THE RIDGE ACROSS ND THEN SEWD INTO THE UPPER GREAT LAKES DURING THE PERIOD. LATE AFTERNOON AND NIGHTTIME STRONG/SEVERE THUNDERSTORMS WILL OCCUR ON ANTICYCLONIC SIDE OF THE RIDGE AXIS ACROSS THE UPR MS VALLEY AND UPR GREAT LAKES WHERE ENHANCED UVVS AND SHEAR WILL TAKE PLACE. ...UPR MIDWEST INTO THE GREAT LAKES REGION... TWO ROUNDS OF STRONG/SEVERE THUNDERSTORMS HAVE BEEN OCCURRING OVERNIGHT ACROSS PARTS OF MN INTO WI LAYING OUT SEVERAL CONVECTIVELY INDUCED BOUNDARIES ACROSS THE REGION. NEXT SHORTWAVE TROUGH WILL MOVE FROM ERN MT THRU ND INTO NERN MN TONIGHT AFTER 30/00Z. LOW LEVEL FLOW OF 35-40 KT IS EXPECTED FROM SWRN KS INTO SERN ND WHICH SHOULD PLAY IN INITIATION OF NEW CONVECTION ACROSS PARTS OF ERN ND THIS EVENING. THIS COUPLED WITH 45-55 KT OF WLY/NWLY MID LEVEL FLOW WILL ENHANCE DEEP LAYER SHEAR SUPPORTIVE FOR UPDRAFTS THAT WILL BECOME AN MCS OVER ERN ND INTO NWRN MN BY EARLY TONIGHT. AIR MASS ACROSS THE PLAINS WILL BE VERY HOT AND MOIST TODAY AS DEW POINTS WILL REMAIN IN THE UPR 60S/LOW 70S S OF OLD CONVECTIVE BOUNDARY ACROSS EAST CENTRAL ND INTO NWRN WI. MLCAPES OF 2500-3000 J/KG WITH DEEP LAYER SHEAR OF 45-50 KT FORMULATES SIMILAR THERMODYNAMIC AND KINEMATIC PROFILE AS WAS IN PLACE OVER MN THIS MORNING. THUS...EXPECT SCATTERED STRONG/SEVERE THUNDERSTORMS TO DEVELOP THIS EVENING AND TONIGHT FROM ERN ND ESEWD INTO NRN WI AND UPR MI/NRN LWR MI WITH MAIN THREAT BEING DAMAGING WINDS AND SOME HAIL. ...TN VALLEY REGION INTO THE CAROLINAS... NAM AND SREF MODELS INDICATE MID LEVEL TROUGH SHIFTS SEWD FROM KY/TN INTO THE CAROLINAS DURING THE PERIOD. NUMEROUS SEVERE REPORTS OCCURRED YESTERDAY IN THIS SAME REGIME AS ONE TROUGH MOVED THROUGH SRN NEW ENGLAND/MID ATLANTIC STATES AND ANOTHER FEATURE AIDED IN CONVECTIVE DEVELOPMENT IN FAVORABLE SEA BREEZE AREA. TROUGHING COMBINED WITH HEATING OF WARM MOIST AIR MASS WILL PROVIDE FAVORABLE THERMODYNAMICS AND UVVS FOR ANOTHER DAY OF WIDESPREAD PULSE THUNDERSTORMS THROUGH THIS REGION. STEEP SFC-3KM LAPSE RATES RESULTING IN TEMP/DEW POINT SPREAD OF 25-30 DEG F INDICATE THAT SOME OF THIS ACTIVITY COULD PRODUCE WET MICRO BURSTS/DAMAGING WINDS THIS AFTERNOON AND EVENING. ...AREAS OF AZ INTO EXTREME SERN NV... LATEST WATER VAPOR IMAGERY ONCE AGAIN DEPICTS MID/UPPER LEVEL CYCLONIC CIRCULATION OVER THE AZ/NM BORDER INTO WRN NM. THIS IS PULLING NWD MONSOONAL MOISTURE FROM MEXICO INTO NM. THUS...NLY MID LEVEL FLOW IN VICINITY OF MOGOLLON RIM ALONG WITH PRESENCE OF MONSOONAL MOISTURE WILL ONCE AGAIN PROVIDE FAVORABLE SHEAR AND THERMODYNAMICS FOR ISOLATED SEVERE STORMS THIS AFTERNOON AND EARLY TONIGHT. ..MCCARTHY.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 16:17:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 12:17:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291617 SWODY1 SPC AC 291615 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1115 AM CDT SAT JUL 29 2006 VALID 291630Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN PORTIONS OF THE NRN PLAINS INTO UPSTATE NY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CENTRAL/ERN CAROLINAS... ...NRN PLAINS ACROSS THE GREAT LAKES AND INTO NRN NEW ENGLAND... BROAD AREA OF MODEST NWLY FLOW ALOFT EXPECTED TO CONTINUE ALONG PERIPHERY OF LARGE UPPER RIDGE ACROSS THE NRN/NERN TIER OF THE U.S. TODAY. AT THE SURFACE...SYNOPTIC COLD FRONT NOW EXTENDING ACROSS SRN QUEBEC/ONTARIO WILL SAG SEWD INTO NRN NEW ENGLAND/LOWER GREAT LAKES THIS AFTERNOON. MIDDLE PORTION OF THIS FRONT HAS BEEN REINFORCED BY SEVERAL MCSS OVER THE CENTRAL/WRN GREAT LAKES AND NRN MS RIVER VALLEY AND CONTINUES TO PUSH SWD TOWARDS NRN IL/SRN LOWER MI AT 16Z...WHILE WRN END REMAINS STALLED INTO SWRN MN AND E-W ACROSS FAR NRN SD. LOCATION OF THIS BOUNDARY WILL BE CRUCIAL TO AFTERNOON SEVERE THREAT...ESPECIALLY OVER THE CENTRAL GREAT LAKES...AS DEEP LAYER SHEAR DIMINISHES CONSIDERABLY SOUTH OF THE GREAT LAKES. APPEARS MORE THAN REASONABLE TO EXPECT INCREASE IN SEVERE THREAT AHEAD OF THE FRONT ACROSS CENTRAL/SERN LOWER MI AND SWRN ONTARIO DURING THE EARLY AFTERNOON AS CAP WEAKENS DUE TO HEATING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR WILL BE MARGINAL BUT STILL SUFFICIENT FOR SOME LINEAR/CLUSTER ORGANIZATION IF STORMS CAN INCREASE OVER THIS REGION WITH SFC-6 KM SHEAR AROUND 20 KT. OTHER STORMS WILL LIKELY INCREASE AND ORGANIZE INTO LINES/CLUSTERS NEAR THE COLD FRONT APPROACHING UPSTATE NY AND POSSIBLY NRN PORTIONS OF NEW ENGLAND THIS AFTERNOON WHERE AIR MASS REMAINS QUITE MOIST DESPITE PASSAGE OF WEAK FRONT YESTERDAY. HAVE ADJUSTED SLGT RISK TO ACCOUNT FOR INCREASED SEVERE THREAT ALONG THIS PORTION OF THE FRONT...PRIMARILY IN THE FORM OF DAMAGING WINDS. MORE ROBUST DEVELOPMENT MAY OCCUR LATE TODAY AND THIS EVENING INTO ERN PORTIONS OF THE NRN PLAINS AND NRN MS RIVER VALLEY WHERE VERY STRONG HEATING WITHIN WARM SECTOR AND FOCUSED ASCENT ALONG SLY LLJ OCCUR NEAR THE FRONT. LARGE SCALE FOCUS WILL REMAIN LIMITED...SUGGESTING DEVELOPMENT WILL NEED TO BE DRIVEN BY STRONG HEATING AND LOW LEVEL CONVERGENCE NEAR STALLED BOUNDARY. REGARDLESS...MODELS IN AGREEMENT IN CONVECTIVE DEVELOPMENT WITHIN STRONGLY UNSTABLE AIR MASS OVER SERN ND/NERN SD/WRN MN BY 00Z. SHEAR WILL BE QUITE STRONG...CONSIDERING DEGREE OF INSTABILITY FORECAST...AND WILL SUPPORT SUPERCELLS. ACTIVITY WILL BE CAPABLE OF LARGE HAIL AND DAMAGING WINDS...AND EVEN A FEW TORNADOES IF LOWER 70F SURFACE DEW POINTS CAN SURVIVE STRONG BOUNDARY LAYER MIXING. THIS ACTIVITY WILL LIKELY BUILD INTO ONE OR MORE MCSS DURING THE EVENING WHICH MOVE ESEWD OVERNIGHT. PATTERN REMAINS QUITE FAVORABLE FOR ANOTHER BOW ECHO-MCS DURING THE EVENING/OVERNIGHT ACROSS THE NRN MS RIVER VALLEY AND INTO THE WRN GREAT LAKES. ...CAROLINAS... VWP AT GSP THIS MORNING CONTINUES TO SHOW 30-40 KT WLY WINDS BETWEEN 2-6 KM ASSOCIATED WITH WEAK MID LEVEL CIRCULATION NOW MOVING ACROSS THE SRN APPALACHIANS. IN ADDITION...MORNING SOUNDINGS ALONG THE CAROLINA COAST MAINTAIN RELATIVELY STEEP MID LEVEL LAPSE RATES AND VERTICAL MAXIMUM THETA-E DIFFERENCES FROM 28-35K. INTENSE UPDRAFTS HAVE BEEN QUITE PRODUCTIVE IN PRODUCING DAMAGING MICROBURSTS WITHIN SIMILAR ENVIRONMENT THE PAST TWO DAYS. SLOW MOVING MID LEVEL SYSTEM AND ASSOCIATED INCREASED WLY FLOW ALOFT MAY ADD IMPETUS FOR STRONG TO SEVERE DOWNBURSTS AS STORMS MAY ORGANIZE A BIT MORE TODAY INTO SMALL LINES/CLUSTERS. ...FL... 12Z SOUNDINGS ACROSS THE STATE WILL AGAIN SUPPORT A FEW STRONG TO SEVERE PULSE STORMS TODAY WITH H85-H5 LAPSE RATES AROUND 6.5 C/KM AND H5 TEMP NEAR -8C AT TBW. MARGINALLY SEVERE HAIL SHOULD ACCOMPANY WET-MICROBURST POTENTIAL WITH STRONGER CORES TODAY. PERSISTENT ESELY LOW LEVEL WINDS SHOULD PUSH EAST COAST SEA BREEZE WELL INLAND AND EXPECT GREATER CONCENTRATION OF STORMS/PULSE-SEVERE THREAT TO OCCUR OVER CENTRAL AND WRN PORTIONS OF THE PENINSULA. ...CENTRAL MT INTO NRN HIGH PLAINS... FRONT REMAINS STALLED FROM NERN WY NWWD ACROSS CENTRAL MT THIS MORNING...EAST OF WHICH AIR MASS REMAINS QUITE MOIST WITH 50+F SURFACE DEW POINTS. STRONG HEATING AND ASCENT AHEAD OF SUBTLE SHORTWAVE TROUGH MAY ALLOW SCATTERED HIGH-BASED THUNDERSTORMS TO DEVELOP NEWD ACROSS CENTRAL MT LATER TODAY. STILL QUESTIONABLE HOW MUCH STORMS CAN ROOT INTO COOLER/MORE MOIST SURFACE AIR EAST OF THE FRONT OVER THE NRN HIGH PLAINS THIS EVENING. HOWEVER...WILL MAINTAIN LOW SEVERE PROBABILITIES ACROSS THIS REGION. ...AZ... CLOUDS REMAIN WIDESPREAD NEAR AND SOUTHEAST OF PRIMARY UPPER LEVEL LOW NOW OVER WRN NM THIS MORNING...WHICH SHOULD HINDER HEATING A BIT TODAY. HOWEVER...AIR MASS REMAINS QUITE MOIST AND MAY ONCE AGAIN SUPPORT A FEW STRONGER STORMS TODAY. SHEAR IS A BIT WEAKER THAN YESTERDAY...BUT AN ISOLATED LARGE HAIL/DAMAGING WIND EVENT REMAINS POSSIBLE. ..EVANS/GUYER.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 20:09:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 16:09:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292009 SWODY1 SPC AC 292007 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0307 PM CDT SAT JUL 29 2006 VALID 292000Z - 301200Z ...THERE IS A MDT RISK OF SVR TSTMS LATE AFTERNOON AND EVENING ACROSS NERN SD/SERN ND AND WEST CENTRAL MN... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN PORTIONS OF THE NRN PLAINS INTO MUCH OF NY/WRN VT... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN CAROLINAS... ...INCREASING POTENTIAL FOR SUPERCELLS PRODUCING VERY LARGE DAMAGING HAIL...DAMAGING WINDS AND A FEW TORNADOES ACROSS SERN ND/ NERN SD/WEST CENTRAL MN DURING THE LATE AFTERNOON AND EVENING... ...NRN PLAINS TO GREAT LAKES REGION... EARLY AFTERNOON SURFACE ANALYSIS SHOWED A COLD FRONT MOVING SWD THROUGH THE UPPER GREAT LAKES REGION. THE WRN PORTION OF THIS BOUNDARY SHOULD REMAINED GENERALLY STATIONARY FROM CENTRAL MN INTO SERN ND TO NWRN SD. A CONVECTIVE OUTFLOW BOUNDARY FROM EARLIER MCS HAS STALLED THIS AFTERNOON ACROSS SRN LOWER MI INTO SRN WI/SERN MN TO ALONG THE ERN PART OF THE ND/SD BORDER REGION. A SURFACE LOW WAS ANALYZED IN CENTRAL SD NEAR PIR. WATER VAPOR IMAGERY INDICATED A MID LEVEL SHORT WAVE TROUGH OVER ERN MT. THIS FEATURE IS PROGGED TO TOP THE RIDGE AND TRACK EWD ACROSS ND THIS EVENING REACHING THE UPPER MS VALLEY BY 12Z SUNDAY. ASCENT AHEAD OF THIS IMPULSE APPEARS TO BE AIDING CURRENT THUNDERSTORM DEVELOPMENT ALONG THE WRN PART OF THE ND/SD BORDER IN THE VICINITY OF THE SURFACE FRONT. ADDITIONAL SURFACE HEATING THIS AFTERNOON WITHIN RICH MOISTURE ALONG/S OF SURFACE BOUNDARIES IS EXPECTED TO MAINTAIN A VERY UNSTABLE AIR MASS /MLCAPE UP TO 4000 J/KG IN ERN SD/SWRN MN/ TO 2500-3000 J/KG INTO SWRN GREAT LAKES REGION. SURFACE HEATING AND INCREASING ASCENT AHEAD OF MT IMPULSE ARE EXPECTED TO FURTHER WEAKEN INHIBITION ACROSS NERN SD/SERN ND INTO WRN MN FOR THUNDERSTORMS TO RAPIDLY DEVELOP BY LATE AFTERNOON. STRONG EFFECTIVE BULK SHEAR VALUES /40-50 KT/ AND INCREASING LOW LEVEL SHEAR ACROSS THE MODERATE RISK AREA WILL SUPPORT SUPERCELLS PRODUCING VERY LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES. THIS ACTIVITY SHOULD GROW UPSCALE INTO ONE OR MORE MCSS ACROSS THE NRN MS VALLEY/WRN GREAT LAKES REGION AS THE MT IMPULSE APPROACHES AND LOW LEVEL CONVERGENCE INCREASES ALONG THE FRONT IN CENTRAL MN PER STRENGTHENING SSWLY LLJ. CAPE/SHEAR VALUES ARE EXPECTED TO REMAIN FAVORABLE FOR SEVERE STORMS TO CONTINUE INTO THE OVERNIGHT PERIOD WITH THIS MCS ACTIVITY...POTENTIALLY EVOLVING INTO ANOTHER BOWING SYSTEM. ...PART OF THE NERN STATES /ERN EXTENT OF SLIGHT RISK/... COLD FRONT...CURRENTLY EXTENDING FROM SRN QUEBEC INTO SERN ONTARIO...WILL CONTINUE TO SPREAD ESEWD INTO THE NERN STATES THIS FORECAST PERIOD. MODERATELY UNSTABLE AIR MASS AHEAD OF THIS FRONT WILL CONTINUE TO MAINTAIN FAVORABLE ENVIRONMENT FOR THUNDERSTORM DEVELOPMENT AS ASCENT SPREADS EWD AHEAD OF A SHORT WAVE TROUGH... NOW CENTERED OVER LAKE HURON. DEEP LAYER SHEAR OF 30-40 KT SUGGESTS A CONTINUED POTENTIAL FOR BOWING LINE STRUCTURES AND SUPERCELLS. ...ERN CAROLINAS... THUNDERSTORMS WILL CONTINUE TO DEVELOP WITHIN MODERATELY UNSTABLE AIR MASS ACROSS THE ERN CAROLINAS INTO ERN GA AS ASCENT SPREADS EWD AHEAD OF SLOW MOVING MID LEVEL CIRCULATION...NOW LOCATED OVER WRN NC/NWRN SC. DESPITE SUFFICIENT INSTABILITY...GENERALLY WEAK DEEP LAYER SHEAR SHOULD PROMOTE A PULSE STORM MODE...WITH DAMAGING DOWNBURST WINDS THE PRIMARY THREAT INTO THE EARLY EVENING. ..PETERS.. 07/29/2006  From swody1 at goshenarc.org Sun Jul 30 20:05:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 30 Jul 2006 16:05:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302005 SWODY1 SPC AC 302003 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0303 PM CDT SUN JUL 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER NRN PLAINS TO OH VALLEY... ...OH VALLEY... AIR MASS ACROSS THE OH VALLEY EXPECTED TO RANGE FROM MODERATELY TO VERY UNSTABLE INTO THE EARLY EVENING. RECENT TRENDS IN ONGOING MCS OVER SRN GREAT LAKES REGION SUGGEST GREATER ESEWD MOVEMENT TO CONTINUE AS INDICATED OVER SERN LOWER MI ATTM. SOME INTENSIFICATION POSSIBLE IN THE WIND POTENTIAL WITH THE SYSTEM AS IT ENCOUNTERS INCREASINGLY UNSTABLE AIR MASS OVER NRN/NERN OH WITH MCS POTENTIALLY REACHING PARTS OF WRN PA/WRN NY BY EARLY EVENING. STORMS SHOULD THEN WEAKEN AS THEY ENCOUNTER LESS FAVORABLE CONDITIONS AS AIR MASS BEGINS TO STABILIZE WITH LOSS OF DAYTIME HEATING. ALTHOUGH THE SWRN FLANK OF THE MCS IS MOVING MORE SLOWLY SWD THROUGH NRN IND/NRN IL AND NERN IA...A VERY UNSTABLE AIR MASS ALONG/S OF THIS REGION AND 30-35 KT EFFECTIVE BULK SHEAR SUPPORTS A CONTINUED THREAT FOR SEVERE STORMS INTO THE EVENING. ...NRN PLAINS EWD TO WRN GREAT LAKES... SURFACE LOW WILL CONTINUE TO MOVE EWD ACROSS THE DAKOTAS THIS FORECAST PERIOD...WHILE WARM FRONT CONTINUES TO LIFT NWD THROUGH ERN ND/NRN MN. A VERY WARM TO HOT AND UNSTABLE AIR MASS /MLCAPE EXCEEDING 4000 J/KG ACROSS MUCH OF MN/ HAS DEVELOPED IN THE WARM SECTOR EAST OF THE SURFACE LOW. WARM SECTOR IS EXPECTED TO REMAIN CAPPED THRU MUCH OF THE AFTERNOON AS INDICATED BY RECENT STRONG CAPPING PER TAMDAR SOUNDINGS AT FAR/BJI. THUS...AFTERNOON/EVENING SEVERE THREAT SHOULD BE LIMITED TO PARTS OF NERN MN/WRN U.P. OF MI AS ELEVATED STORMS CONTINUE TO DEVELOP ON COOL SIDE OF CONVECTIVE OUTFLOW WHERE SHEAR/CAPE VALUES REMAIN FAVORABLE FOR SOME SEVERE. OVERNIGHT AS THE LOW LEVEL JET INCREASES TO 40-50 KT IN WARM SECTOR AHEAD OF SURFACE LOW...SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP VICINITY BOUNDARY IN ND EWD WITH POSSIBILITY FOR ONE OR MORE MCS/S TRACKING EWD VICINITY THE INTERNATIONAL BORDER FROM ND TO LS. DAMAGING WINDS WOULD LIKELY ACCOMPANY THE MCS/S GIVEN BOTH LARGE AMOUNT OF INSTABILITY AND STEEP LAPSE RATES. ...NRN HIGH PLAINS... UPPER SHORT WAVE TROUGH...NOW LOCATED OVER SRN BRITISH COLUMBIA/ PACIFIC NW...WILL TRACK NEWD OVER NRN ROCKIES REACHING SASKATCHEWAN BY 12Z MONDAY. AS THIS OCCURS...60 METER HEIGHT FALLS ARE EXPECTED INTO THE NRN PLAINS TONIGHT WITH RESULTANT EWD SHIFT OF RIDGE CREST TOWARD THE WRN GREAT LAKES. ASCENT AHEAD OF THIS TROUGH SHOULD SUPPORT AN INCREASING POTENTIAL FOR THUNDERSTORMS OVER THE HIGHER TERRAIN OF CENTRAL MT AND/OR ALONG A COLD FRONT PROGRESSING EWD ACROSS MT. 60 PLUS KT MID LEVEL WIND MAX ACCOMPANYING UPPER TROUGH ACROSS MT THIS EVENING SUGGESTS SEVERE STORMS INCREASINGLY LIKELY...MAINLY AS ACTIVITY MOVES EWD ENCOUNTERING GREATER INSTABILITY CLOSER TO THE MT/ND BORDER THIS EVENING. ..PETERS.. 07/30/2006  From swody1 at goshenarc.org Mon Jul 31 00:52:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 30 Jul 2006 20:52:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 310052 SWODY1 SPC AC 310050 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0750 PM CDT SUN JUL 30 2006 VALID 310100Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM ND INTO THE UPPER OH VALLEY... ...ND INTO THE UPPER GREAT LAKES... EVENING WATER VAPOR IMAGERY SHOWS SHORT WAVE TROUGH LIFTING NEWD THROUGH ERN MT WITH AN ASSOCIATED BELT OF 40-45 KT MID-LEVEL FLOW SPREADING EWD ACROSS ND INTO THE RED RIVER VALLEY. AIR MASS ALONG AND S OF SURFACE LOW /NEAR BIS/ AND ATTENDANT SURFACE FRONT EXTENDING ENEWD INTO NWRN MN HAS ONCE AGAIN BECOME QUITE HOT WITH TEMPERATURES WARMING TO WELL OVER 100 F OVER CNTRL SD INTO S-CNTRL ND. STRONG CAPPING APPEARS TO HAVE INHIBITED SURFACE-BASED STORM DEVELOPMENT THUS FAR EXCEPT OVER FAR NERN MT IN CLOSER PROXIMITY TO SHORT WAVE TROUGH /REF. MCD 1680 FOR ADDITIONAL SHORT TERM GUIDANCE/. FARTHER TO THE E...REMNANT OUTFLOW BOUNDARY FROM SATURDAY NIGHT-EARLY SUNDAY MCS EXTENDS FROM INTERSECTION WITH SYNOPTIC FRONT OVER N-CNTRL MN SEWD THROUGH WRN WI INTO N-CNTRL IL. AGAIN TONIGHT...00Z MPX SOUNDINGS INDICATES THAT THE STRONGEST INSTABILITY RESIDES ALONG AND JUST TO THE S OF THIS OUTFLOW BOUNDARY OVER CNTRL/SRN MN WHERE MLCAPES REMAIN AROUND 3000-4000 J/KG. LATEST SHORT TERM MODEL GUIDANCE SUGGESTS THAT TSTMS /MAINLY ELEVATED/ WILL INCREASE IN COVERAGE OVERNIGHT N OF FRONTAL ZONE ACROSS NRN PARTS OF ND/MN...EVENTUALLY EWD INTO LAKE SUPERIOR AND THE UP OF MI AS LOW-LEVEL WAA/ISENTROPIC UPGLIDE INCREASE N OF FRONT AND OUTFLOW BOUNDARY. REGIONAL VWPS INDICATE THAT SUFFICIENT VERTICAL SHEAR WILL EXIST FOR SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. GREATEST POTENTIAL FOR A TORNADO WOULD EXIST WITH ANY NEAR SURFACE BASED SUPERCELLS THAT CAN MATURE NEAR SYNOPTIC FRONT/OUTFLOW BOUNDARY INTERSECTION OVER NWRN/N-CNTRL MN WHERE LOW-LEVEL SHEAR IS MAXIMIZED. POTENTIAL FOR UPSCALE GROWTH INTO AN MCS WILL EXIST LATE TONIGHT OVER THE ARROWHEAD/LAKE SUPERIOR/UP OF MI WITH ANY ASSOCIATED WIND THREAT DEVELOPING SEWD INTO NRN WI AND PERHAPS LOWER MI. ...UPPER OH VALLEY... CLUSTERS OF TSTMS ARE IN PROGRESS OVER E-CNTRL OH/W-CNTRL PA WITHIN MOIST AND MODERATELY UNSTABLE AIR MASS WITH MLCAPES OF AROUND 2000 J/KG /PER 00Z PIT SOUNDING/. SHORT WAVE TROUGH OVER LOWER MI INTO LAKE ERIE IS FORECAST TO CONTINUE SEWD TONIGHT...PROVIDING BACKGROUND FORCING TO SUSTAIN ACTIVITY CONVECTION INTO THE OVERNIGHT HOURS. IT APPEARS THE GREATEST POTENTIAL FOR ADDITIONAL STRONG TO SEVERE TSTMS WILL EXIST ALONG THE WRN FLANK OF ONGOING TSTM COMPLEX WHICH WILL BE MAINTAINED BY LOW-LEVEL WAA ALONG MODEST WLY LLJ. VERTICAL SHEAR IS NOT PARTICULARLY STRONG...THOUGH THE POTENTIAL WILL EXIST FOR LOCALLY DAMAGING WINDS...ESPECIALLY IF A COLD POOL CAN ORGANIZE. ...CNTRL GULF COAST... LARGE TSTM COMPLEX HAS EVOLVED OVER SERN MS/SWRN AL WITHIN A MOIST AND MODERATELY UNSTABLE AIR MASS WITH MLCAPES OF 1000-2000 J/KG. THIS SYSTEM APPEARS TO HAVE ORGANIZED A COLD POOL AND SOME THREAT OF LOCALLY DAMAGING WINDS WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AS STORMS MOVE/DEVELOP SWD TOWARD THE COAST. ...AZ... TSTM CLUSTERS OVER SRN COCONINO AND NAVAJO COUNTIES IN NRN AZ APPEAR TO HAVE SOME ORGANIZATION AS THEY MOVE GENERALLY SWD AT 10-15 KT. ENVIRONMENT REMAINS RELATIVELY MOIST AND MODERATELY UNSTABLE...WHICH SHOULD MAINTAIN STORMS SWD TOWARD THE LOWER DESERTS LATER THIS EVENING. ARE VWPS AND 00Z SOUNDINGS INDICATE THAT VERTICAL SHEAR IS QUITE WEAK WHICH SHOULD LIMIT THE OVERALL SEVERE THREAT. STILL...LOCALLY DAMAGING WINDS WILL REMAIN POSSIBLE WITH MOST INTENSE STORMS. ..MEAD.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 05:40:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 01:40:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 310540 SWODY1 SPC AC 310538 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1238 AM CDT MON JUL 31 2006 VALID 311200Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE UPPER MS VALLEY INTO UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF UPSTATE NY INTO WRN NEW ENGLAND... ...SYNOPSIS... PROGRESSIVE LARGE-SCALE PATTERN IS FORECAST FROM THE GREAT BASIN AND PACIFIC NW EWD ACROSS SRN CANADA AND THE NRN TIER OF STATES INTO NEW ENGLAND. WITHIN THIS PATTERN...SHORT WAVE TROUGH NOW OVER FAR ERN MT/WRN ND WILL LIFT NEWD ACROSS SRN MANITOBA INTO ONTARIO AHEAD OF STRONGER IMPULSE SHIFTING EWD THROUGH THE PRAIRIE PROVINCES. MEANWHILE TO THE W...SHORT WAVE WILL MOVE EWD FROM THE ERN PACIFIC INTO THE PACIFIC NW AND GREAT BASIN. IN THE LOW-LEVELS...SURFACE COLD FRONT FROM THE RED RIVER VALLEY SWWD INTO THE CNTRL HIGH PLAINS WILL SHIFT EWD THROUGH THE PERIOD INTO THE UPPER GREAT LAKES...FOCUSING STRONG TO POTENTIALLY SEVERE STORMS THIS AFTERNOON INTO TONIGHT. ...UPPER GREAT LAKES/UPPER MS VALLEY... MCS CURRENTLY EVOLVING OVER NERN ND/NWRN MN IS EXPECTED TO BE ONGOING AT THE ONSET OF THE FORECAST PERIOD OVER PORTIONS OF N-CNTRL MN INTO THE ARROWHEAD REGION...DRIVEN LARGELY BY STRONG LOW-LEVEL WAA ASSOCIATED WITH SWLY LLJ EXTENDING FROM THE CNTRL PLAINS INTO UPPER GREAT LAKES. LATEST MODEL GUIDANCE SUGGESTS THAT THE MAJORITY OF THIS NOCTURNAL CONVECTION WILL MOVE/DEVELOP NEWD INTO SRN ONTARIO TODAY WITH THE SRN FLANK POSSIBLY AFFECTING LOCATIONS AS FAR S AS THE U.P. WITH THE PRIMARY THREAT BEING DAMAGING WINDS. ADDITIONAL STORMS WILL BE POSSIBLE THIS AFTERNOON ALONG COLD FRONT FROM NRN MN SWWD INTO ERN SD WHERE STEEP LAPSE RATES AND MOIST BOUNDARY LAYER CONDITIONS /DEWPOINTS OF 65-75 F/ WILL CONTRIBUTE TO MLCAPES OF 1500-3000 J/KG. WHILE THE STRONGER LARGE-SCALE FORCING WILL GRADUALLY SHIFT NEWD INTO ONTARIO...SUSTAINED LOW-LEVEL CONVERGENCE AND DAYTIME HEATING SHOULD BE SUFFICIENT TO OVERCOME CAP. STRONGEST MID-LEVEL WIND FIELDS /45-55 KTS AT 500 MB/ AND RESULTANT VERTICAL SHEAR ARE FORECAST ACROSS NRN MN...ALONG SRN PERIPHERY OF SHORT WAVE TROUGH MOVING THROUGH MANITOBA/WRN ONTARIO WHERE A FEW SUPERCELLS CAPABLE OF MAINLY DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE. FARTHER S INTO SD...BOTH SHEAR AND INSTABILITY WILL BE WEAKER...THOUGH MULTICELLS WITH LOCALLY STRONG WIND GUSTS AND SOME SEVERE HAIL WILL BE POSSIBLE. ...NY INTO WRN NEW ENGLAND... PERSISTENT SWLY LLJ FROM THE CNTRL PLAINS THROUGH THE GREAT LAKES INTO SWRN ONTARIO/SWRN QUEBEC IS FORECAST TO MAINTAIN A FEED OF A MOIST AND MODERATELY UNSTABLE AIR INTO TSTM CLUSTERS/MCSS THAT ARE EXPECTED TO PERSIST ACROSS SRN ONTARIO INTO SWRN QUEBEC. THESE STORMS MAY BEGIN TO TURN MORE SEWD LATE TONIGHT INTO PORTIONS OF UPSTATE NY AND WRN NEW ENGLAND AS ACTIVITY SHIFTS E OF MEAN MID-LEVEL RIDGE AXIS. FORECAST SOUNDINGS INDICATE THAT INSTABILITY WILL REMAIN MARGINAL...THOUGH RELATIVELY STRONG UNIDIRECTIONAL WIND PROFILES WILL BE SUPPORTIVE OF DAMAGING WIND GUSTS. ...CNTRL/SRN HIGH PLAINS... STEEP LAPSE RATES ARE FORECAST TO DEVELOP TODAY AHEAD OF COLD FRONT MOVING SWD THROUGH THE CNTRL HIGH PLAINS...CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. VERTICAL SHEAR WILL REMAIN QUITE WEAK...THOUGH THE STEEP LAPSE RATES /ESPECIALLY IN THE LOW-LEVELS/ WILL BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS CAPABLE OF MAINLY STRONG WIND GUSTS. ...CNTRL/ERN NV... ENVIRONMENT IS FORECAST TO BECOME INCREASINGLY SUPPORTIVE OF TSTMS THIS AFTERNOON INTO EVENING AS FORCING FOR ASCENT ASSOCIATED WITH APPROACHING MID-LEVEL TROUGH COUPLED WITH DAYTIME HEATING CONTRIBUTES TO STEEP LAPSE RATES AND MARGINAL INSTABILITY. DESPITE THIS MARGINAL INSTABILITY...VERTICAL SHEAR WILL BE QUITE STRONG...AND GIVEN THE INCREASED LARGE-SCALE FORCING...POTENTIAL WILL EXIST FOR A FEW ORGANIZED STORMS CAPABLE OF SEVERE HAIL AND LOCALLY DAMAGING WINDS. ..MEAD/GRAMS.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 12:55:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 08:55:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 311256 SWODY1 SPC AC 311254 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT MON JUL 31 2006 VALID 311300Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPR MS VLY AND UPR GRT LKS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF UPSTATE NY AND WRN NEW ENGLAND... ...SYNOPSIS... DOMINANT MS VLY UPR RIDGE WILL EXPAND E AND SLIGHTLY N INTO THE UPR OH VLY/MID ATLANTIC REGION THIS PERIOD AS SHORTWAVE TROUGH NOW ENTERING SASKATCHEWAN CONTINUES E INTO WRN ONTARIO. FARTHER W... DISTURBANCE NOW NEARING THE NRN CA CST SHOULD REACH THE NRN GRT BASIN BY 12Z TUESDAY. COLD FRONT ACCOMPANYING SASKATCHEWAN TROUGH...NOW EXTENDING FROM NE ND INTO NW NEB LIKELY WILL CONTINUE ONLY SLOWLY SE INTO THE CNTRL PLNS ...BUT SHOULD PROGRESS STEADILY E ACROSS THE UPR MS VLY/UPR GRT LKS BY TONIGHT/EARLY TUESDAY. ...UPR MS VLY/UPR GRT LKS... CONVECTIVE SYSTEMS NOW OVER WRN LK SUPERIOR AND THE ERN U.P. OF MI SHOULD CONTINUE GENERALLY ESE INTO ONTARIO LATER THIS MORNING... AHEAD OF SLOWLY EXPANDING UPR RIDGE. STRONG LOW-LEVEL WARM ADVECTION FROM THE WEST MAY SUPPORT BACK-BUILDING/REGENERATIVE ACTIVITY ON THE SWRN FLANKS OF THESE SYSTEMS. SOME OF THE STORMS COULD AFFECT NRN AND ERN PARTS OF THE U.P...AND POSSIBLY EXTREME NRN LWR MI...WITH LOCALLY DAMAGING WIND. BUT THE BULK OF THIS SLIGHTLY ELEVATED ACTIVITY SHOULD REMAIN IN CANADA. FARTHER W...A BAND OR TWO OF ELEVATED STORMS MAY PERSIST THROUGH MIDDAY IN POST-FRONTAL/POST CONVECTIVE OUTFLOW ENVIRONMENT IN NRN MN/ERN ND. RELATIVELY WARM MID LEVEL TEMPERATURES AND WEAK LARGE SCALE ASCENT SHOULD LIMIT POTENTIAL FOR SUSTAINED STORMS WITH HAIL. LATER TODAY...EXPECT THAT SURFACE HEATING AND WEAK ASCENT S OF PASSING TROUGH WILL INITIATE SURFACE-BASED STORMS ALONG COLD FRONT IN NRN/CNTRL MN AND THE ERN DAKOTAS. WARM MID LEVEL TEMPERATURES WILL CONTINUE TO LIMIT DEGREE OF DIURNAL DESTABILIZATION. BUT VERY WARM...FAIRLY MOIST AND DEEPLY-MIXED BOUNDARY LAYER SHOULD YIELD MLCAPE OF 1500-3000 J/KG. UNIDIRECTIONAL MID LEVEL WSWLY FLOW ON SRN FRINGE OF CANADIAN TROUGH SHOULD INCREASE TO AROUND 50 KTS ACROSS NRN MN...AND TO AOA 30 KTS IN ERN SD/SRN MN. DEEP LAYER OF LARGELY UNIDIRECTIONAL FLOW...HI PWS AND DEEP MIXED LAYERS ALL SUGGEST POTENTIAL FOR ORGANIZATION INTO LINES/CLUSTERS...WITH EMBEDDED SUPERCELLS SUPPORTING BOWING SEGMENTS WITH HIGH WINDS AND POSSIBLY HAIL. POTENTIAL FOR SUSTAINED SEVERE SHOULD DECREASE WITH SWD EXTENT...BUT MAY CONTINUE INTO TONIGHT EWD INTO WI/UPR MI. ...NY/NEW ENGLAND... EWD EXPANSION OF CNTRL STATES RIDGE WILL ENHANCE WARM ADVECTION ACROSS SRN ONTARIO AND THE ST LAWRENCE RVR VLY LATER TODAY THROUGH EARLY TUESDAY. THIS SHOULD SUSTAIN TSTM CLUSTERS/MCSS THAT WILL AFFECT SRN ONTARIO LATER TODAY. THIS ACTIVITY MAY BEGIN TO FORWARD-PROPAGATE SE INTO PARTS OF UPSTATE NY AND WRN NEW ENGLAND LATE TONIGHT/EARLY TUESDAY AS DOWNSTREAM BOUNDARY LAYER WARMS/ MOISTENS. WHILE FORECAST SOUNDINGS INDICATE THAT INSTABILITY WILL REMAIN MARGINAL...RELATIVELY STRONG UNIDIRECTIONAL DEEP WIND FIELDS MAY SUPPORT LOCALLY DAMAGING WINDS. ...CNTRL/SRN HIGH PLAINS... STEEP LOW LEVEL LAPSE RATES WILL DEVELOP WITH AFTERNOON HEATING INVOF COLD FRONT LEE TROUGH SETTLING S/SE ACROSS THE CNTRL HIGH PLAINS. WHILE VERTICAL SHEAR WILL REMAIN WEAK...DEEPLY-MIXED ENVIRONMENT WITH VERY WARM SURFACE TEMPERATURES MAY SUPPORT A FEW PULSE STORMS WITH HIGH WIND. ...CNTRL/ERN NV... ENVIRONMENT MAY SUPPORT A FEW STRONG TSTMS THIS AFTERNOON AND EVENING AS FORCING FOR ASCENT WITH NRN CA TROUGH AND DAYTIME HEATING DESTABILIZE REGION. WHILE INSTABILITY LIKELY WILL REMAIN FAIRLY MARGINAL /SBCAPE AROUND 500 J PER KG/...VERTICAL SHEAR WILL STRENGTHEN AND MAY SUPPORT DEVELOPMENT OF A FEW ORGANIZED STORMS CAPABLE OF DAMAGING WIND AND POSSIBLY MARGINALLY SEVERE HAIL. ..CORFIDI/GRAMS.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 16:22:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 12:22:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 311622 SWODY1 SPC AC 311620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT MON JUL 31 2006 VALID 311630Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS UPPER GREAT LAKES AND UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF UPSTATE NY AND WRN NEW ENGLAND... ...SYNOPSIS... WARM UPPER RIDGE SHIFTS EWD ACROSS GREAT LAKES AS A VIGOROUS SYSTEM TRACKS WELL N OF CONUS ACROSS SCENTRAL CANADA. IN THE WESTERN U.S. A BROAD TROUGH MOVES INTO NRN INTERMOUNTAIN REGION AS WEAK UPPER CIRCULATION THAT HAS RESIDED OVER THE WEEKEND IN NM BEGINS TO LIFT SLOWLY NEWD INTO CENTRAL HIGH PLAINS. COLD FRONT TRAILING SWWD FROM STRONG CANADIAN SYSTEM THRU ERN ND TO ERN CO WILL PUSH STEADILY EWD TO UPPER GREAT LAKES BY LATER TONIGHT STRETCHING SWWD ACROSS NEB TO SERN CO. VERY MOIST AIR MASS BOTH FROM SWLY FLOW AHEAD OF NM UPPER SYSTEM AND LARGE AREA OF GULF MOISTURE ALREADY IN PLACE COVERS MUCH OF REGION FROM COLD FRONT TO APPALACHIANS. ...GREAT LAKES ... THE VERY WARM MID LEVEL TEMPERATURES SPREADING EWD WITH UPPER RIDGE WILL LIMIT SEVERE STORM POTENTIAL AHEAD OF COLD FRONT EVEN WITH ABUNDANT MOISTURE...INSTABILITY AND A FAVORABLY SHEARED ENVIRONMENT CURRENTLY IN PLACE ACROSS THE UPPER GREAT LAKES. OUTFLOW BOUNDARY THAT CURRENTLY EXTENDS WWD FROM CONVECTIVE COMPLEX NRN LH WOULD BE A FOCUS OF SURFACE BASED THUNDERSTORMS NRN LWR MI THIS AFTERNOON AS AIR MASS ALREADY VERY UNSTABLE AND WEAKLY CAPPED. HOWEVER WITH WARMER AIR ALOFT SPREADING EWD SEVERE POTENTIAL SHOULD DIMINISH BY EVENING. UPSTREAM OVER MN AND NRN WI STRONG HEATING WILL WEAKEN CAP SUFFICIENTLY TO ALLOW THUNDERSTORMS TO INITIATE BY MID/LATE AFTERNOON AS MLCAPES CLIMB TO NEAR 2000 J/KG. HOWEVER WITH VERY WARM MID LEVELS...SEVERE THUNDERSTORM POTENTIAL WILL BE LIMITED TO DOWNBURSTS WITH STEEP LOW LEVEL LAPSE RATES AND ONLY A MARGINAL SEVERE HAIL THREAT. ...NY/VT... HAVE CONTINUED A CONDITIONAL LOW END SEVERE THREAT FOR TONIGHT FOR POTENTIAL OF MCS RIDING ACROSS UPR RIDGE AND TRACKING SEWD INTO NRN NY AND VT. WHILE DEEP LAYER SHEAR OF 40KT WOULD SUPPORT A SEVERE THREAT THE INSTABILITY IS CERTAINLY A CONCERN GIVEN THE WARM 500 MB TEMPERATURES AND LAPSE RATES OF 6C/KM OR LESS. WILL CONTINUE PRIMARILY A CONDITIONAL WIND DAMAGE THREAT FOR MCS OCCURRENCE AFTER 00Z. ..HALES/GUYER.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 20:00:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 16:00:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 312000 SWODY1 SPC AC 311958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT MON JUL 31 2006 VALID 312000Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS UPPER MIDWEST/UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS UPSTATE NY AND WESTERN NEW ENGLAND... ...GREAT LAKES/UPPER MIDWEST INTO CENTRAL PLAINS... WATER VAPOR IMAGERY FEATURES FAIRLY POTENT SHORTWAVE TROUGH MOVING EASTWARD ACROSS SASKATCHEWAN/MANITOBA AT MID AFTERNOON...WITH AN ASSOCIATED COLD FRONT EXTENDING FROM NORTH CENTRAL MN INTO WESTERN NEB. GIVEN THE DEGREE OF CAPPING/WEAK VERTICAL SHEAR IN THE WARM SECTOR...THE MAIN SEVERE POTENTIAL WILL LIKELY BE RIGHT ALONG AND/OR IN THE IMMEDIATE COOL SIDE OF THE SURFACE COLD FRONT. ALTHOUGH SOME HAIL IS POSSIBLE...WARM MID LEVEL TEMPERATURES SUGGEST THE PRIMARY SEVERE THREAT WILL BE POTENTIALLY DAMAGING DOWNBURSTS WITHIN A RATHER UNSTABLE AIRMASS. THE MORE ORGANIZED SEVERE POTENTIAL WILL BE ACROSS MN/FAR EASTERN SD INTO NORTHWEST WI/WESTERN U.P. OF MICH THROUGH THIS EVENING...ALTHOUGH AN ISOLATED SEVERE THREAT MAY EXIST AS FAR SOUTHWEST AS THE CENTRAL HIGH PLAINS. ...UPSTATE NY AND WESTERN PORTIONS OF NEW ENGLAND... POTENTIAL WILL EXIST FOR ONE OR MORE SMALL MCS/S TO ROUND THE RIDGE FROM EASTERN ONTARIO/FAR SOUTHERN QUEBEC INTO UPSTATE NY AND WESTERN PORTIONS OF NORTHERN NEW ENGLAND LATER THIS EVENING/OVERNIGHT. AHEAD OF THIS POSSIBLE ACTIVITY...AN INCREASINGLY MOIST/UNSTABLE AIRMASS WILL CONTINUE TO ADVECT INTO THE REGION THROUGH TONIGHT...WITH EXISTING FLOW FIELDS/VERTICAL SHEAR OF 40-45 KTS CONDITIONALLY SUPPORTIVE OF ORGANIZED STORMS/MCS MAINTENENCE. EVEN SO...THE TIME OF DAY/MODEST DEGREE OF INSTABILITY AND MILD MID LEVEL TEMPERATURES MAY TEND TO LIMIT THE OVERALL THREAT. PRIMARY HAZARD WOULD BE DAMAGING WIND GUSTS...WITH SOME HAIL POSSIBLE AS WELL. ..GUYER/HART.. 07/31/2006  From swody1 at goshenarc.org Sat Jul 1 05:38:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 01:38:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 010537 SWODY1 SPC AC 010535 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1235 AM CDT SAT JUL 01 2006 VALID 011200Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES ACROSS THE CNTRL PLAINS TO THE FRONT RANGE... ...SYNOPSIS... DEEP LAYER FRONT ASSOCIATED WITH UPPER MS VALLEY TO GREAT LAKES SHORT WAVE IMPULSE WILL SETTLE INTO ZONE OF LARGE SCALE CONFLUENCE BETWEEN SUBTROPICAL RIDGE AXIS ESTABLISHED ACROSS THE SRN STATES...AND FASTER ZONAL FLOW REGIME EVOLVING ACROSS THE NRN BORDER STATES. WHILE DYNAMIC FORCING AND DEEPER ASCENT ACCOMPANYING THE LOW AMPLITUDE SHORT WAVE TROUGH WILL SPREAD RAPIDLY EAST FROM THE GREAT LAKES TO NEW ENGLAND THIS PERIOD...LIFT ALONG THE TRAILING/WRN EXTENSION OF THE FRONT...FROM THE MS VALLEY WWD TO THE FRONT RANGE...WILL BE MAINTAINED AND DIURNALLY ENHANCED BY LOW LEVEL CONFLUENCE...WARM AIR ADVECTION...AND OROGRAPHIC FORCING. AN AMALGAMATION OF WEAK SUBTROPICAL DISTURBANCES AND WEAK PERTURBATIONS CAST OFF FROM THE WESTERLIES WILL DRIFT ACROSS THE SRN STATES FROM FL AND THE GULF ACROSS TX TO THE SOUTHWEST AND FOUR CORNERS AND AID SCATTERED TSTM DEVELOPMENT ACROSS THESE AREAS. ...UPPER MS VALLEY/GREAT LAKES... FRONTAL ZONE WILL DEVELOP EWD/SEWD INTO INCREASINGLY UNSTABLE AIR MASS FROM WI/UPPER MI TO LOWER MI AND SWRN ONTARIO. GREATER LOW LEVEL MOISTURE ADVECTING ENEWD FROM THE CORN BELT COUPLED WITH DIURNAL HEATING WILL CONTRIBUTE TO THE DEVELOPMENT OF MODEST INSTABILITY /MLCAPE 1000-1500 J/KG/ AS THE SHORT WAVE TROUGH AND FRONT APPROACH DURING THE AFTERNOON. LOW THROUGH MID LEVEL FLOW WILL INCREASE THROUGH THE DAY AND LEAD TO MORE THAN SUFFICIENT SHEAR FOR ORGANIZED STORMS. LINEAR FORCING WITH THE FRONT SUGGESTS POTENTIAL WILL EXIST FOR LINE SEGMENT/BOW ECHO FORMATION WITH THE WIND DAMAGE THREAT INCREASING FROM WI ACROSS LOWER MI THROUGH THE AFTERNOON AND INTO THE EVENING. SUPERCELL TORNADO AND LARGE HAIL POTENTIAL CANNOT BE RULED OUT WITH FORECAST SOUNDINGS DEPICTING INCREASINGLY STRONG LOW LEVEL FLOW AND EFFECTIVE SRH VALUES IN EXCESS OF 200 M2/S2 ACROSS WEAKLY CAPPED WARM SECTOR. LAKE BREEZE BOUNDARY/CELL INTERACTIONS MAY ALSO LOCALLY ENHANCE THE CHANCE FOR BRIEF TORNADOES. ...CNTRL PLAINS TO FRONT RANGE... SURFACE TEMPERATURES WILL AGAIN CLIMB INTO THE 90S F OVER THE PLAINS AND LEAD TO THE DEVELOPMENT OF NEARLY DRY ADIABATIC LAPSE RATES FROM THE SURFACE THROUGH AT LEAST 3KM AGL. THIS HEATING WILL OCCUR COINCIDENT WITH AN AXIS OF GREATER MOISTURE BENEATH A STRONG CAP AND FOCUSED WITHIN THE CONFLUENT/FRONTAL ZONE WHERE MLCAPE MAY LOCALLY INCREASE TO OVER 2000 J/KG. COMBINATION OF DEEP MIXING AND WEAK HEIGHT FALLS ARE FORECAST TO OVERCOME INHIBITION AND RESULT IN SCATTERED VIGOROUS LATE DAY THROUGH EVENING TSTM DEVELOPMENT. OUTFLOW DOMINANT STORMS WITH DAMAGING WINDS AND SOME HAIL ARE EXPECTED. ALTHOUGH...FARTHER WEST...MOIST POST-FRONTAL UPSLOPE FLOW AND SOMEWHAT GREATER LOW LEVEL DIRECTIONAL SHEAR COULD SUPPORT A FEW HIGH-BASED STORMS WITH SUPERCELLULAR CHARACTERISTICS FROM WRN NEB TO THE FRONT RANGE. ...COASTAL CAROLINAS... STRONG HEATING OF VERY MOIST/WEAKLY CAPPED AIR MASS MAY AGAIN LEAD TO THE DEVELOPMENT OF STRONG TO ISOLATED SEVERE STORMS NEAR THE SEA BREEZE. SIMILAR TO FRIDAY...HAIL COULD OCCUR WITH A FEW OF THE STRONGER UPDRAFTS. WET MICROBURSTS ALSO APPEAR POSSIBLE BASED ON STEEP THETAE LAPSE RATES AND FORECAST DCAPE VALUES OVER 1000 J/KG. ...AZ... THERMODYNAMIC ENVIRONMENT HAS CHANGED LITTLE FROM PAST FEW DAYS AND SHOULD AGAIN SUPPORT THE DEVELOPMENT OF STORMS ACROSS THE HIGHER TERRAIN DURING THE AFTERNOON. DEEP LAYER ELY FLOW ON THE SRN PERIPHERY OF SUBTROPICAL RIDGE WILL AGAIN STEER CONVECTIVE OUTFLOW WWD/SWWD INTO THE LOWER DESERTS WITH ATTENDANT ISOLATED WIND DAMAGE THREAT. ...TX... COOL POCKET ALOFT ASSOCIATED WITH ORPHANED AND NEARLY STATIONARY MID LEVEL VORTEX WILL AGAIN CONTRIBUTE TO THE DEVELOPMENT OF SCATTERED TO NUMEROUS AFTERNOON STORMS ACROSS PARTS OF SCNTRL TX AND THE RIO GRANDE VALLEY. DESPITE WEAK FLOW/SHEAR...MODEST INSTABILITY AND POTENTIAL FOR WELL-MIXED BOUNDARY LAYER COULD RESULT IN A FEW STRONG TO ISOLATED DAMAGING WIND GUSTS. SURGE OF TROPICAL MOISTURE...POSSIBLY ASSOCIATED WITH AN ELY WAVE...IS FORECAST TO SPREAD INLAND ACROSS THE TX GULF COAST AND COULD LEAD TO AN INCREASED THREAT OF ISOLATED WET DOWNBURSTS...OR A BRIEF TORNADO/WATERSPOUT. ...ORE.. UPSLOPE FLOW AND WEAK HEIGHT FALLS MAY AGAIN PROMOTE THE DEVELOPMENT OF A FEW POTENT STORMS WITH SMALL HAIL ACROSS CASCADES DURING THE AFTERNOON. THIS ACTIVITY SHOULD DRIFT EAST ACROSS RELATIVELY DEEP/DRY SUB CLOUD LAYER WITH A SMALL CHANCE OF DAMAGING WINDS. ..CARBIN/GUYER.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 13:00:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 09:00:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011256 SWODY1 SPC AC 011255 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0755 AM CDT SAT JUL 01 2006 VALID 011300Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM THE CENTRAL HIGH PLAINS TO THE UPPER GREAT LAKES AREA.... ...WI/MI AREA THIS AFTERNOON/EVENING... A LOW AMPLITUDE SHORTWAVE TROUGH OVER ERN ND/NW MN THIS MORNING WILL MOVE ESEWD OVER THE UPPER GREAT LAKES REGION LATER THIS AFTERNOON INTO EARLY TONIGHT. A SURFACE LOW WILL MOVE ACROSS SRN ONTARIO IN ADVANCE OF THIS MID LEVEL WAVE...WHILE A TRAILING COLD FRONT ADVANCES SEWD ACROSS IA/WI/MI THIS AFTERNOON. SEVERAL DAYS OF EVAPOTRANSPIRATION HAVE RAISED SURFACE LAYER DEWPOINTS INTO THE MID-UPPER 60S ACROSS THE CORN BELT...IN THE CORRIDOR ALONG A REMNANT NW-SE BAROCLINIC ZONE WHERE THE BOUNDARY LAYER HAS BEEN SHELTERED FROM DEEPER MIXING. THIS MOIST LAYER IS STILL RELATIVELY SHALLOW...BUT SHOULD PERSIST TODAY ACROSS IA/WI AND SPREAD NEWD INTO LOWER MI FROM IL/INDIANA BY AFTERNOON. ADDITIONALLY...A PLUME OF RELATIVELY STEEP MID LEVEL LAPSE RATES WILL OVERSPREAD THE WI/MI AREA IN ADVANCE OF THE MID LEVEL TROUGH. THE STEEP LAPSE RATES...LOW-LEVEL MOISTURE...AND AFTERNOON TEMPERATURES IN THE MID-UPPER 80S WILL ALL CONTRIBUTE TO THE DEVELOPMENT OF MLCAPE VALUES OF 1500-2500 J/KG AHEAD OF THE COLD FRONT BY AFTERNOON. SCATTERED THUNDERSTORMS SHOULD DEVELOP INVOF THE FRONT ACROSS NRN WI/WRN UPPER MI BY MID AFTERNOON...WITH ADDITIONAL STORM DEVELOPMENT EXPECTED FARTHER SW INTO WI AND NE IA BY EVENING. FORECAST VERTICAL SHEAR APPEARS SUFFICIENT FOR A FEW SUPERCELLS IN A BROKEN BAND NEAR THE FRONT...THOUGH SOME OF THE CONVECTION MAY ALSO EVOLVE INTO BOWING LINE SEGMENTS. DAMAGING WINDS AND LARGE HAIL WILL THE MAIN SEVERE THREATS. THE TORNADO THREAT IS MORE UNCERTAIN AND WILL DEPEND ON LOCAL ENHANCEMENTS TO LOW-LEVEL MOISTURE IN THE REGION OF STRONGER LOW-LEVEL SHEAR FROM ERN WI INTO LOWER MI LATER THIS AFTERNOON/EVENING. ...CENTRAL PLAINS/HIGH PLAINS THIS AFTERNOON INTO TONIGHT... A SURFACE COLD FRONT IS MOVING SEWD ACROSS NEB AND NE CO AS OF 12Z...THOUGH THE BOUNDARY SHOULD STALL THIS AFTERNOON FROM ERN CO ACROSS NW KS TO SE NEB AND SRN IA. STRONG SURFACE HEATING WILL OCCUR S OF THE BOUNDARY...WHILE SOMEWHAT RICHER MOISTURE AND MODERATE INSTABILITY WILL BE MAINTAINED IN A NARROW BAND IMMEDIATELY N OF THE FRONT. A FEW THUNDERSTORMS SHOULD DEVELOP ALONG THE BOUNDARY BY LATE AFTERNOON AND PERSIST INTO THE EARLY OVERNIGHT HOURS. VERTICAL SHEAR WILL BE MARGINALLY FAVORABLE FOR SUPERCELLS N OF THE BOUNDARY AND IN THE UPSLOPE FLOW AREA OF NE CO/SE WY...WHICH MAY TEND TO LOCALLY ENHANCE THE THREAT FOR LARGE HAIL. OTHERWISE...STORMS SHOULD EVOLVE INTO A FEW SMALL CLUSTERS WITH THE POTENTIAL TO PRODUCE ISOLATED LARGE HAIL AND DAMAGING WINDS INTO TONIGHT. ...SE ATLANTIC STATES THIS AFTERNOON... ONE WEAK MID LEVEL WAVE IS MOVING OFFSHORE OF NC...WHILE OTHER SUBTLE WAVES ARE LOCATED UPSTREAM OVER TN/KY. 12Z SOUNDINGS SHOW THE POTENTIAL FOR MODERATE INSTABILITY THIS AFTERNOON ACROSS THE CAROLINA COASTAL PLAINS WHERE LOW-LEVEL MOISTURE WILL BE MAXIMIZED. MORNING SOUNDINGS ALSO REVEAL STEEP LAPSE RATES BELOW 700 MB OVER THE SRN APPALACHIANS/TN VALLEY. STRONG SURFACE HEATING WILL RESULT IN PROFILES THAT MAY SUPPORT ISOLATED STRONG DOWNBURSTS OVER PORTIONS OF THE SRN APPALACHIANS AND COASTAL CAROLINAS...AS WELL AS ISOLATED HAIL. ..THOMPSON/GUYER.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 16:30:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 12:30:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011629 SWODY1 SPC AC 011628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT SAT JUL 01 2006 VALID 011630Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM THE GREAT LAKES INTO THE CENTRAL HIGH PLAINS.... ...SYNOPSIS... MID/UPPER LEVEL SHORTWAVE TROUGH/ASSOCIATED VORTICITY MAX IS LOCATED OVER WRN PORTIONS OF LK SUPERIOR THIS MORNING EXTENDING SSWWD THRU CENTRAL IA. THIS FEATURE IS EXPECTED TO TRACK EWD THIS AFTN OVER THE NRN PARTS OF THE GREAT LAKES REGION BEFORE SWINGING NEWD OVER SERN ONTARIO TNGT. BROAD RIDGING WILL CONTINUE ACROSS THE SRN TIER OF THE U.S. WITH THE MAIN BAND OF WESTERLIES REMAINING FROM THE NRN PLATEAU REGION ESEWD THRU THE LOWER GREAT LAKES AND SRN NEW ENGLAND. AT THE SFC...COLD FRONT EXTENDS FROM A LOW JUST NW OF THE NWRN SHORES OF LK SUPERIOR SWWD ACROSS NWRN WI AND NWRN IA INTO SWRN NEB. THIS FRONT WILL PROGRESS EWD WITH THE MID/UPPER LEVEL TROUGH AND PLAY AS THE MAIN SOURCE OF FORCING FOR ACTIVITY THIS AFTN AND TNGT. ...MUCH OF LOWER MI SWWD INTO SRN WI... COLD FRONT WILL PUSH EWD ACROSS MUCH OF NRN AND CENTRAL LOWER MI THIS AFTN AND TRAIL SWWD ACROSS SRN WI. MORNING RAOB DATA INDICATED MAIN BAND 35-45 KT SWLY LOW LEVEL FLOW EXTENDS FROM NERN KS INTO NERN WI AND IS EXPECTED TO REACH FROM NRN IL INTO NERN LOWER MI BY THIS EVENING. WINDS AT 500 MB ARE EXPECTED TO BE WLY AT 45-55 KT FROM SERN MN INTO NRN LOWER MI AND BE SOMEWHAT DIVERGENT ENHANCING VERTICAL SHEAR AND UVVS ALONG/AHEAD OF THE FRONTAL BOUNDARY BY MID AFTN INTO EARLY TNGT. IN ADDITION...AIR MASS IS ALREADY EXPERIENCING SOME DESTABILIZATION AS SFC DEW POINTS ARE IN THE MID 60S AND CURRENT MESOANALYSIS SHOWS LIFTED INDICES AROUND -6 AND MUCAPES ABV 2000 J/KG. THUS...PRIND ARE THUNDERSTORMS WILL BE MOVING INTO WRN LOWER MI EARLY THIS AFTN AHEAD OF THE ADVANCING FRONTAL BOUNDARY. SOME OF THIS ACTIVITY IS EXPECTED TO BECOME SEVERE WITH THE MAIN THREATS BEING DAMAGING WINDS AND HAIL. ...AREAS FROM IA INTO THE HIGH PLAINS OF CO/WY... QUASI STATIONARY FRONTAL BOUNDARY IS EXPECTED TO EXTEND FROM SWRN WI THRU CENTRAL IA INTO NWRN KS AND SERN CO BY LATER THIS AFTN. NWLY WINDS AT THE SFC ATTM ARE EXPECTED TO BECOME MORE ELY BY TONIGHT WHICH WILL ENHANCE UPSLOPE FLOW TO THE AREA. SEVERAL WEAK SHORTWAVES ARE FORECAST TO COME FROM MONSOONAL EXTENSION OVER THE INTERMOUNTAIN REGION MOVING ESEWD WITHIN THE MAIN BAND OF THE WESTERLIES AIDING IN THE DEVELOPMENT OF WIDELY SCATTERED THUNDERSTORMS OVER THE HIGH PLAINS THEN ENEWD ALONG/JUST N OF THE FRONTAL BOUNDARY THIS EVENING AND EARLY TONIGHT. SOME OF THE ACTIVITY COULD PRODUCE SOME HAIL AND DAMAGING WINDS GIVEN VERY STEEP LAPSE RATES BETWEEN 8 AND 8.5C/KM. ..MCCARTHY/TAYLOR.. 07/01/2006  From swody1 at goshenarc.org Sat Jul 1 19:56:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 15:56:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011955 SWODY1 SPC AC 011953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT SAT JUL 01 2006 VALID 012000Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE HIGH PLAINS...CNTRL PLAINS...UPPER MIDWEST AND GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE FAR NERN STATES... ...UPPER MIDWEST/GREAT LAKES... A WELL-DEFINED SHORTWAVE TROUGH IS EVIDENT ON WATER VAPOR IMAGERY OVER WI AND LAKE SUPERIOR. A LINE OF THUNDERSTORMS IS DEVELOPING JUST AHEAD OF THE PRIMARY VORTICITY MAX ALONG A COLD FRONT OVER NRN WI AND UPPER MI. THUNDERSTORMS SHOULD CONTINUE TO INCREASE IN COVERAGE MOVING SEWD ACROSS ERN WI...UPPER MI AND INTO NRN LOWER MI LATE THIS AFTERNOON. OBJECTIVE ANALYSIS CURRENTLY SHOWS A MAXIMUM OF STRONG INSTABILITY OVER WCNTRL WI WHERE MLCAPE VALUES RANGE FROM 2500 TO 3000 J/KG. INSTABILITY IS INCREASING ACROSS LOWER MI WHERE MLCAPE VALUES RANGE FROM 1000 TO 1500 J/KG. IN ADDITION...FORECAST SOUNDINGS SHOW STRONG VERTICAL SHEAR PROFILES IN PLACE ASSOCIATED WITH A 60 KT MID-LEVEL JET CENTERED OVER NERN WI. THE STRONG SHEAR AND INSTABILITY SUGGEST SUPERCELLS AND/BOW ECHOES WILL BE LIKELY. A PLUME OF STEEP MID-LAPSE RATES EXIST FROM IA EXTENDING ENEWD INTO LOWER MI SUGGESTING LARGE HAIL WILL BE LIKELY WITH SUPERCELLS. THE STRONG LOW-LEVEL SHEAR MAY BE FAVORABLE FOR A TORNADO OR TWO WITH SUPERCELLS THAT PERSIST INTO THE LATE AFTERNOON. WIND DAMAGE WILL ALSO BE LIKELY WITH BOW ECHOES EMBEDDED IN THE LINE DUE TO THE STEEP LOW-LEVEL LAPSE RATES AND STRONG LOW-LEVEL FLOW IN PLACE. AN ISOLATED SEVERE THREAT SHOULD CONTINUE INTO THE EVENING AS A LARGE MCS ORGANIZES AND TRACKS SEWD ACROSS SRN WI...LAKE MI AND THE LOWER PENINSULA OF MI. ...FAR NERN STATES... WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER LOW OVER ERN QUEBEC WITH STRONG WLY FLOW IN PLACE ACROSS NEW ENGLAND. LARGE-SCALE ASCENT AND COLD AIR ALOFT ASSOCIATED WITH THE TROUGH IS RESULTING IN SCATTERED THUNDERSTORM DEVELOPMENT IN THE NRN APPALACHIAN MTNS AND IN THE COASTAL PLAINS OF NEW ENGLAND. ALTHOUGH INSTABILITY IS RELATIVELY WEAK...LAPSE RATES ARE VERY STEEP AS SHOWN BY OBJECTIVE ANALYSIS. THIS COMBINED WITH THE STRONGER VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS SUGGEST A SEVERE THREAT WILL LIKELY CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON. LARGE HAIL AND ISOLATED WIND DAMAGE WILL BE POSSIBLE WITH THE STRONGER MULTICELL STORMS. ...HIGH PLAINS/CNTRL PLAINS... WATER VAPOR IMAGERY CURRENTLY SHOWS A PLUME OF MONSOONAL MOISTURE IN PLACE ACROSS THE FOUR CORNERS REGION EXTENDING NEWD INTO THE HIGH PLAINS. SCATTERED STRONG THUNDERSTORMS HAVE DEVELOPED FROM ERN MT SWD ACROSS ERN WY INTO NRN CO. OBJECTIVE ANALYSIS SHOWS POCKETS OF MODERATE INSTABILITY IN PLACE ACROSS THE HIGH PLAINS EXTENDING EWD INTO SRN NEB ALONG A FRONTAL BOUNDARY WHERE ADDITIONAL STORMS MAY INITIATE LATE THIS AFTERNOON. UPSLOPE FLOW IS IN PLACE ACROSS MOST OF THE REGION WHICH IS CREATING STRONG DIRECTIONAL SHEAR PROFILES IN THE LOWER TO MID-LEVELS. AS A RESULT...THE STORMS WILL HAVE ACCESS TO MODERATE VERTICAL SHEAR SUGGESTING A SUPERCELL THREAT WILL CONTINUE THIS AFTERNOON THROUGH EARLY EVENING. STEEP MID-LEVEL LAPSE RATES WILL FAVOR LARGE HAIL AS THE MAIN THREAT ALTHOUGH AN ISOLATED WIND DAMAGE THREAT MAY ALSO ACCOMPANY THE STRONGER CELLS. ..BROYLES.. 07/01/2006  From swody1 at goshenarc.org Sun Jul 2 01:08:35 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 01 Jul 2006 21:08:35 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020107 SWODY1 SPC AC 020106 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT SAT JUL 01 2006 VALID 020100Z - 021200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES SWWD TO THE CNTRL PLAINS... ...UPPER MS VALLEY/GREAT LAKES... VIGOROUS SHORT WAVE IMPULSE WAS DEPICTED WELL BY LATEST WATER VAPOR SATELLITE LOOP AND WAS TRACKING EAST ACROSS THE NWRN GREAT LAKES REGION. ASSOCIATED FRONTAL BAND/WIND SHIFT WAS SITUATED FROM NRN LOWER MI WSWWD ACROSS WI/IA...AND THEN FROM SERN NEB TO NWRN KS. DESPITE SOMEWHAT LIMITED INSTABILITY DOWNWIND FROM LAKE MI...ACROSS MUCH OF LOWER MI...STRONG DYNAMIC FORCING ASSOCIATED WITH THE MID LEVEL IMPULSE AND FRONTAL LIFT SHOULD CONTINUE TO SUPPORT AT LEAST A COUPLE OF SEVERE STORMS WITH WIND AND HAIL AS THE FRONT CROSSES THE REGION TONIGHT. BOTH CAP AND INSTABILITY STRENGTHEN SWWD ALONG THE FRONT/WIND SHIFT...FROM WI/IA SWWD ACROSS NEB/KS. DIURNAL HEATING COUPLED WITH LIFT ALONG THE FRONT HAVE EFFECTIVELY OVERCOME INHIBITION AND RESULTED IN INTENSE STORM DEVELOPMENT FROM NERN IA INTO SRN WI OVER THE PAST FEW HOURS. RUC SOUNDINGS AND DIAGNOSTIC DATA INDICATE THAT STRONG DIRECTIONAL AND SPEED SHEAR IN THE STORM UPDRAFT LAYER WERE CONTRIBUTING TO HIGH VALUES OF LOW LEVEL SR-HELICITY...AND EFFECTIVE CLOUD-BEARING SHEAR WAS MORE THAT SUFFICIENT FOR SUPERCELLS. THE PRESENCE OF MODEST AMBIENT INHIBITION AND WARM/DRY AIR ABOVE THE SURFACE LAYER ARE PROBABLY RESULTING IN A RELATIVELY HIGH LFC WHICH MAY TEND TO LESSEN A MORE SIGNIFICANT TORNADO THREAT. HOWEVER... ACTIVITY WILL REMAIN CAPABLE OF LARGE HAIL AND DAMAGING WINDS AS IT SPREADS ESEWD FROM THE MS RIVER ACROSS SRN WI AND NRN IL AND SWRN MI THROUGH LATE TONIGHT. ...CNTRL PLAINS... MOIST POST-FRONTAL UPSLOPE FLOW HAS AIDED DEEP CONVECTION DEVELOPING EAST ACROSS ERN CO...NWRN NEB...AND EXTREME SWRN SD. IN ADDITION... MORE ISOLATED POST-FRONTAL ACTIVITY HAS INITIATED FROM NWRN KS ACROSS ERN NEB WHERE MOISTENING AND FRONTAL LIFT HAVE ACTED TO OVERCOME STRONG INHIBITION. WHILE THERE APPEARS TO BE SUFFICIENT INSTABILITY AND POCKETS OF GREATER DEEP LAYER SHEAR TO MAINTAIN A CHANCE FOR SEVERE STORMS ACROSS THESE AREAS...GENERALLY WEAKER LARGE SCALE UPWARD MOTION MAY LIMIT COVERAGE AND PERSISTENCE THROUGH LATER TONIGHT. INCREASING NOCTURNAL LOW LEVEL JET FROM KS TO NEB WILL BE DIRECTED INTO THE DEEP LAYER FRONTAL ZONE AND MAY PROVE ADEQUATE TO MAINTAIN A CHANCE FOR SCATTERED SEVERE STORMS OVER THE CNTRL PLAINS FOR AT LEAST SEVERAL MORE HOURS. ..CARBIN.. 07/02/2006  From swody1 at goshenarc.org Sun Jul 2 05:58:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 01:58:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020558 SWODY1 SPC AC 020556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT SUN JUL 02 2006 VALID 021200Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL/NRN PLAINS...ACROSS THE MIDWEST/UPPER OH VALLEY...TO THE NORTHEAST... ...SYNOPSIS... GENERALLY WEAK HEIGHT FALLS WILL ACCOMPANY A PAIR OF LOW AMPLITUDE SHORT WAVE TROUGHS EMBEDDED WITHIN A LARGER SCALE BAND OF MODEST WNWLY FLOW FROM SCNTRL CANADA TO THE NORTHEAST THIS PERIOD. THE LEAD DISTURBANCE...CURRENTLY CROSSING THE GREAT LAKES...WILL CONTINUE EAST TO QUEBEC BEFORE MOVING ACROSS THE ST. LAWRENCE VALLEY TO NRN NEW ENGLAND THROUGH SUNDAY NIGHT. THE FRONTAL ZONE ASSOCIATED WITH THIS FEATURE...EMBEDDED WITHIN A RELATIVELY STRONG DEEP-LAYER FLOW FIELD...WILL SPREAD ESEWD ACROSS THE NORTHEAST THROUGH TONIGHT. THE WRN EXTENSION OF THIS FRONT WILL REMAIN QUASI-STATIONARY FROM THE UPPER OH VALLEY/MIDWEST TO THE CNTRL PLAINS. WEAK MID/UPPER LEVEL PERTURBATIONS...EMANATING IN PART FROM WIDESPREAD DEEP CONVECTION ACROSS THE ROCKIES...IN COMBINATION WITH PERSISTENT MASS INFLOW ON THE NOSE OF GREAT PLAINS LOW LEVEL JET...WILL MAINTAIN THE PROSPECTS FOR ASCENT ALONG THIS PORTION OF THE STALLED BOUNDARY. THE NEXT UPSTREAM IMPULSE IN THE FASTER NWLY FLOW ACROSS SRN CANADA AND THE NRN U.S. WILL BRING A WEAK COLD FRONT ACROSS THE NRN PLAINS AND UPPER MS VALLEY THROUGH EARLY MONDAY. ...NORTHEAST... CONVECTION IS FORECAST TO CONTINUE SPREADING EAST FROM THE GREAT LAKES AND UPSTATE NY INTO NRN NEW ENGLAND EARLY TODAY AIDED BY LIFT AND WEAK DESTABILIZATION ON THE NOSE OF WLY LOW LEVEL JET. IN THE WAKE OF THIS EARLY WARM CONVEYOR BELT CONVECTION...WEAK TO MODERATE INSTABILITY /MLCAPE 500-1500 J PER KG/ SHOULD DEVELOP IN AN AXIS FROM SRN NY/NRN PA ENEWD ACROSS SRN/CNTRL NEW ENGLAND. SCATTERED CONVECTION OCCURRING ALONG THE WEAK COLD FRONT/WIND SHIFT SHOULD INCREASE IN BOTH COVERAGE AND INTENSITY AS GREATER INSTABILITY IS REALIZED AND FRONTAL FORCING SPREADS ESEWD. RELATIVELY STRONG WLY FLOW THROUGH THE TROPOSPHERE AND POTENTIALLY STEEP LOW LEVEL LAPSE RATES SUGGEST FAST MOVING BANDS/CLUSTERS OF STORMS WITH A TENDENCY TO BOW OUT AND PRODUCE WIND DAMAGE. STRONG LOW LEVEL SHEAR...THE POSSIBILITY OF RESIDUAL OUTFLOW/DIFFERENTIAL HEATING BOUNDARIES...AND LOCALLY LOWER LFC...MAY ENHANCE THE THREAT FOR A FEW SUPERCELLS WITH LARGE HAIL AND PERHAPS A TORNADO FOR ANY CELLS REMAINING DISCRETE. GREATEST SEVERE POTENTIAL APPEARS TO EVOLVE FROM PA TO NRN NJ/SERN NY...AND ACROSS SWRN NEW ENGLAND THROUGH LATE AFTERNOON WHERE GREATEST CHANCE FOR STRONG DESTABILIZATION WILL OCCUR AHEAD OF STRENGTHENING MID LEVEL FLOW. ...OH VALLEY/MIDWEST TO CNTRL HIGH PLAINS... MODERATE INSTABILITY /MLCAPES OF 1500-2500 J PER KG/ WILL DEVELOP ALONG THE QUASI-STATIONARY FRONT FROM OH WWD TO THE CNTRL PLAINS GIVEN STEEP LAPSE RATES/STRONG HEATING AND RELATIVELY MOIST LOW LEVEL AIR MASS. PERSISTENT LOW-LEVEL CONVERGENCE...COUPLED WITH THE INFLUENCE OF WEAK IMPULSES EMBEDDED WITHIN MID-LEVEL FLOW...WILL AID IN THE DEVELOPMENT OF SCATTERED AFTERNOON AND EVENING STORMS. WHILE STRONGER WLY FLOW WILL RESIDE A BIT NORTH OF THE GREATEST INSTABILITY...SUFFICIENT EFFECTIVE SHEAR WILL EXIST FOR ORGANIZED SEVERE STORMS...INCLUDING A FEW SUPERCELLS AND BOWING STRUCTURES. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER HAZARDS. MOIST UPSLOPE FLOW INTO HIGHER HEATED TERRAIN WILL OVERCOME INHIBITION AND LEAD TO STORM DEVELOPMENT ACROSS CO/WY. THIS ACTIVITY...SIMILAR TO SATURDAY...WILL MOVE SLOWLY EAST INTO MOIST POST-FRONTAL AIR MASS WHERE SHEAR AND INSTABILITY WILL MARGINALLY SUPPORT SOME HAIL AND WIND POTENTIAL. ONE OR TWO OF THESE CLUSTERS OF STORMS MAY PERSIST WELL INTO THE NIGHT AS NOCTURNAL LOW LEVEL JET INTENSIFIES AND MAINTAINS MASS INFLOW/LIFT ACROSS THE FRONTAL ZONE. ...NRN PLAINS... LOW LEVEL WARM AIR ADVECTION IS EXPECTED TO INTENSIFY LATE IN THE PERIOD AHEAD OF SHORT WAVE TROUGH DEVELOPING SEWD FROM SCNTRL CANADA. STEEP LAPSE RATES...INCREASING ASCENT AND MOISTENING... FROM THE DAKOTAS TO MN...MAY SUPPORT THE DEVELOPMENT OF A LATE-NIGHT MCS ACROSS THESE AREAS THROUGH EARLY MONDAY. A FEW HAIL EVENTS APPEAR POSSIBLE WITH THIS SCENARIO. ..CARBIN/GUYER.. 07/02/2006  From swody1 at goshenarc.org Sun Jul 2 12:56:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 08:56:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 021255 SWODY1 SPC AC 021253 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 AM CDT SUN JUL 02 2006 VALID 021300Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY FROM THE UPPER OH VALLEY INTO NEW ENGLAND...AND INTO TONIGHT FROM THE CENTRAL HIGH PLAINS TO PORTIONS MN/IA.... ...UPPER OH VALLEY TO NEW ENGLAND TODAY... A MID LEVEL SHORTWAVE TROUGH OVER SW QUEBEC WILL MOVE EWD OVER NEW ENGLAND TODAY...WHILE ANOTHER UPSTREAM WAVE OVER SRN ONTARIO FOLLOWS A SIMILAR TRAJECTORY IN THE BROAD CYCLONIC FLOW REGIME FROM NRN MN TO MAINE. A SURFACE CYCLONE WILL ACCOMPANY THE MID LEVEL WAVE ACROSS NRN MAINE...WHILE A WEAK SURFACE TROUGH TRAILS SWWD ACROSS NY/PA INTO THE NRN OH VALLEY STATES. ONGOING ELEVATED STORMS OVER NY/VT/NH WILL SPREAD EWD TODAY. SOME OF THIS CONVECTION MAY INTENSIFY ACROSS PA/NY/SRN NEW ENGLAND BY MIDDAY AS THE LOW LEVELS DESTABILIZE...WHILE THE PRIMARY THREAT FOR SEVERE STORMS ACROSS MAINE WILL BE IN THE WAKE OF THIS EARLY CONVECTION. MODEST WARM SECTOR INSTABILITY IS EXPECTED TODAY WITH SURFACE DEWPOINTS IN THE LOW-MID 60S AND TEMPERATURES GENERALLY IN THE 80S...WHILE VERTICAL SHEAR WILL BE STRONGER ACROSS NRN NEW ENGLAND IN ASSOCIATION WITH THE MAIN BELT OF MID LEVEL WESTERLIES. BOTH BOWING SEGMENTS AND SUPERCELLS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS...MARGINALLY SEVERE HAIL...AND PERHAPS A TORNADO. ...CENTRAL HIGH PLAINS TO MS VALLEY THIS AFTERNOON/TONIGHT... A DIFFUSE FRONTAL ZONE EXTENDS FROM ERN CO/NW KS TO SRN IA AND NRN IL/SRN LOWER MI. THIS BOUNDARY HAS BEEN REINFORCED SOME BY OVERNIGHT RAINFALL...AND DIFFERENTIAL HEATING MAY HELP MAINTAIN ITS IDENTITY ALONG THE SRN FRINGE OF THE MID LEVEL WESTERLIES. MODERATE INSTABILITY AGAIN CAN BE EXPECTED ALONG THE IMMEDIATE B0UNDARY WHERE SURFACE HEATING AND A BELT OF MID 60 DEWPOINTS CONTRIBUTE TO MLCAPE VALUES NEAR 1500 J/KG. MEANWHILE...VERTICAL SHEAR SHOULD BE MARGINAL FOR SUPERCELLS...WITH MULTICELL CLUSTERS THE MORE PROBABLE STORM MODE. ISOLATED LARGE HAIL AND DAMAGING OUTFLOW GUSTS WILL BE POSSIBLE WITH THE STRONGEST STORMS THIS AFTERNOON. THE SURFACE BOUNDARY SHOULD BEGIN TO LIFT NWD TONIGHT AS A SWLY LLJ DEVELOPS FROM THE CENTRAL PLAINS TO THE MID/UPPER MS VALLEY... IN RESPONSE TO ANOTHER MID LEVEL TROUGH DIGGING SEWD TOWARD WRN ONTARIO AND THE MN ARROWHEAD AREA. WAA ON THE NOSE OF THE LLJ AND ASCENT ALONG A DEVELOPING SURFACE COLD FRONT SHOULD SUPPORT ELEVATED THUNDERSTORMS TONIGHT AS THE LOW LEVELS GRADUALLY MOISTEN/DESTABILIZE. LARGE HAIL WILL BE THE MAIN SEVERE THREAT...THOUGH ISOLATED DAMAGING WINDS MAY ALSO OCCUR SINCE THE SURFACE-BASED INVERSION LAYER SHOULD BE FAIRLY SHALLOW OVERNIGHT. ...INTERIOR ORE LATE THIS AFTERNOON... A WEAK MID LEVEL TROUGH /APPARENT IN WATER VAPOR IMAGERY NEAR 40 N AND 127 W/ WILL MOVE NEWD OVER EXTREME NW CA AND ORE BY LATE TODAY. THIS APPROACHING WAVE WILL PROVIDE WEAK LARGE SCALE ASCENT OVER ORE...WHILE STRONG SURFACE HEATING AND OBSERVED BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 40S F CONTRIBUTE TO LATE AFTERNOON MLCAPE VALUES OF 500-1000 J/KG. EXPECT A FEW THUNDERSTORMS TO DEVELOP NEAR AND E OF THE CASCADES THIS AFTERNOON AND PERSIST INTO EARLY TONIGHT WITH THE POTENTIAL FOR MARGINALLY SEVERE HAIL/WINDS. ..THOMPSON/GUYER.. 07/02/2006  From swody1 at goshenarc.org Mon Jul 3 01:24:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 02 Jul 2006 21:24:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 030101 SWODY1 SPC AC 030059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT SUN JUL 02 2006 VALID 030100Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM IA ESEWD INTO THE OH VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM DELMARVA TO NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CENTRAL/NRN HIGH PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN ORE AND SRN ID... ...IA ESEWD THROUGH OH VALLEY... EARLY EVENING SURFACE ANALYSIS SHOWED A BOUNDARY EXTENDING FROM NRN OH WWD TO THE IA/MO BORDER TO SERN NEB THEN SWWD INTO NRN TO WRN KS. ERN PART OF THIS FRONT WILL MOVE SLOWLY SWD THROUGH OH AIDED BY A SHORT WAVE TROUGH MOVING EWD THROUGH THE SRN GREAT LAKES REGION. THE PART OF THE BOUNDARY ALONG THE IA/MO BORDER SHOULD LIFT N TOWARD CENTRAL IA OVERNIGHT. ASCENT AHEAD OF THE SRN GREAT LAKES TROUGH IS EXPECTED TO SUPPORT ADDITIONAL STORMS ACROSS CENTRAL IND/CENTRAL-NRN OH INTO WRN PA WHERE THE AIR MASS IS EXPECTED TO REMAIN MODERATELY UNSTABLE THROUGH THIS EVENING. DEEP WLY WIND FIELDS WILL CONTINUE TO SUPPORT LINE SEGMENTS...WITH EFFECTIVE BULK SHEAR VALUES /35-45 KT/ ALSO SUGGESTING A CONTINUED POTENTIAL FOR SUPERCELLS ACROSS PARTS OF NRN IND/NRN OH TO WRN PA. FARTHER W...STRENGTHENING SWLY LLJ IS EXPECTED TO EXTEND NEWD INTO SWRN/CENTRAL IA OVERNIGHT. DESTABILIZATION AND INCREASING CONVERGENCE/LOW LEVEL WAA IN THE VICINITY OF THE SURFACE BOUNDARY AND NOSE OF LLJ SHOULD ALLOW FOR ADDITIONAL STORMS TO DEVELOP NNEWD INTO CENTRAL IA/NRN IL...POTENTIALLY REACHING FAR SERN MN/SRN WI. EFFECTIVE BULK SHEAR AND ELEVATED MODERATE INSTABILITY EXPECTED TO SUPPORT THE POTENTIAL FOR LARGE HAIL. IN ADDITION...POINT FORECAST SOUNDINGS SUGGEST A RATHER SHALLOW SURFACE INVERSION OVERNIGHT RESULTING IN A THREAT FOR STRONG WIND GUSTS TO REACH THE SURFACE. ...DELMARVA TO NEW ENGLAND... SURFACE TROUGH EXTENDED SWD FROM MAINE TO THE DELMARVA REGION... WHILE A COLD FRONT EXTENDED FROM NRN MAINE SWWD TO UPSTATE NY. THESE BOUNDARIES ARE EXPECTED TO CONTINUE TO MOVE EWD OVERNIGHT AND SHOULD BE JUST OFF THE NORTHEAST COAST BY 12Z MONDAY. EFFECTIVE DEEP LAYER SHEAR REMAINS SUFFICIENT FOR ORGANIZED STORMS WITH THE GREATEST SEVERE THREAT FOR THE NEXT FEW HOURS /UNTIL 03 OR 04Z/ ACROSS NRN NEW ENGLAND AND SWD FROM NJ TO THE DELMARVA REGION. ...PARTS OF CENTRAL/NRN HIGH PLAINS... ONGOING CLUSTERS OF STORMS ACROSS NERN CO AND WRN NEB SHOULD GROW UPSCALE INTO ONE OR TWO MCS/S TONIGHT AS A SLY LLJ STRENGTHENS ALONG THE HIGH PLAINS. MODERATE ELEVATED INSTABILITY AND SUFFICIENT EFFECTIVE BULK SHEAR VALUES SHOULD SUPPORT A THREAT FOR HAIL AND STRONG WIND GUSTS WITH THE STRONGEST ACTIVITY. ...ERN ORE/SRN ID... A PAIR OF SHORT WAVE TROUGHS /1. MOVING INTO WRN ORE AND 2. MOVING INTO SRN ID/ PER WATER VAPOR IMAGERY WILL CONTINUE TO TRACK NEWD. ASCENT WITH THESE FEATURES WILL CONTINUE TO SUPPORT ADDITIONAL THUNDERSTORMS THROUGH THE EVENING ACROSS CENTRAL/ERN ORE INTO MUCH OF SRN ID. MODERATE INSTABILITY AND DEEP LAYER SHEAR RANGING FROM 35-40 KT WILL AID IN A THREAT FOR HAIL AND STRONG WIND GUSTS. ...ERN DAKOTAS/MN/NWRN WI/WRN U.P. OF MI... MID LEVEL IMPULSE AND ACCOMPANYING 50-60 KT WLY JET WILL TRACK FROM SRN MANITOBA EWD INTO ONTARIO/UPPER GREAT LAKES OVERNIGHT. ASCENT WITHIN THE ENTRANCE REGION OF THIS JET WILL CONTINUE TO SUPPORT THUNDERSTORM DEVELOPMENT THIS FORECAST PERIOD ALONG A COLD FRONT SPREADING EWD ACROSS THE ERN DAKOTAS/NRN MN. ALTHOUGH DEEP LAYER SHEAR WILL BE SUFFICIENT FOR ORGANIZED STORMS...WEAK INSTABILITY SHOULD LIMIT THE SEVERE THREAT. ..PETERS.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 06:05:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 02:05:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 030604 SWODY1 SPC AC 030603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT MON JUL 03 2006 VALID 031200Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE NRN/CENTRAL HIGH PLAINS EWD TO THE GREAT LAKES/OH VALLEY AND NY... ...SYNOPSIS... MID/UPPER LEVEL CLOSED LOW WILL TRACK ESEWD ACROSS NRN ONTARIO TODAY MAINTAINING BROAD CYCLONIC FLOW REGIME FROM THE NRN PLAINS/UPPER MS VALLEY ACROSS THE GREAT LAKES/OH VALLEY TO THE NERN STATES. PRIMARY SHORT WAVE TROUGH ASSOCIATED WITH THIS UPPER LOW IS PROGGED TO MOVE SEWD FROM THE UPPER MS VALLEY INTO THE GREAT LAKES REGION. SEVERAL WEAK MID LEVEL IMPULSES SHOULD TRAVERSE THE SRN EXTENT OF STRONGER FLOW ALOFT FROM THE CENTRAL PLAINS EWD THROUGH THE LOWER MO TO OH VALLEYS AND OFF THE MID ATLANTIC COAST. MEANWHILE...UPSTREAM SHORT WAVE TROUGH...CURRENTLY LOCATED ACROSS THE NRN INTERMOUNTAIN WEST... IS EXPECTED TO TOP THE RIDGE AXIS OVER WRN MT EARLY TODAY AND THEN TURN ESEWD ACROSS MT REACHING THE WRN DAKOTAS LATE TONIGHT. IN THE LOW LEVELS...SURFACE BOUNDARY EXTENDING FROM OH WWD TO CENTRAL IL THEN GENERALLY WSWWD ACROSS SRN IA TO WRN KS/ERN CO IS EXPECTED TO REMAIN QUASI-STATIONARY THROUGH THE FORECAST PERIOD. MEANWHILE...COLD FRONT ACCOMPANYING UPPER MS VALLEY/GREAT LAKES SHORT WAVE TROUGH SHOULD EXTEND FROM THE MN ARROWHEAD SWWD TO ERN SD AT 12Z TODAY AND THEN EXTEND FROM THE ERN U.P. OF MI ACROSS ERN WI TO SERN IA BY 04/00Z. ...GREAT LAKES/OH VALLEY/PARTS OF UPPER AND MID MS VALLEY... THUNDERSTORMS MAY BE ONGOING AT THE START OF THE PERIOD ESEWD FROM IA INTO PARTS OF THE OH VALLEY. MODELS SUGGEST THIS ACTIVITY SHOULD WEAKEN THIS MORNING. MOIST AIR MASS /SURFACE DEWPOINTS IN THE MID 60S TO AROUND 70/ ALREADY IN PLACE ALONG THE QUASI-STATIONARY BOUNDARY EXTENDING FROM MID MS VALLEY INTO OH VALLEY IS EXPECTED TO BECOME MODERATELY UNSTABLE TODAY. WEAK MID LEVEL IMPULSE PROGGED TO MOVE ACROSS THIS REGION IS EXPECTED TO SUPPORT SCATTERED THUNDERSTORM DEVELOPMENT THROUGH THE AFTERNOON WITH HAIL AND STRONG WIND GUSTS BEING THE PRIMARY THREATS. FARTHER N AND W...STRENGTHENING SWLY LOW LEVEL WINDS AHEAD OF THE COLD FRONT WILL ALLOW MOISTURE TO RETURN NEWD INTO THE UPPER GREAT LAKES REGION WITH SURFACE DEWPOINTS IN THE UPPER 50S TO AROUND 60 REACHING MUCH OF THE UPPER PENINSULA OF MI AND NRN LOWER MI. SURFACE HEATING WITHIN THIS MOIST AIR MASS WILL RESULT IN MODERATE INSTABILITY IN THE WARM SECTOR WITH STRONGEST INSTABILITY EXPECTED ACROSS PARTS OF SRN WI/ERN IA AND NRN IL WHERE SURFACE DEWPOINTS WILL BE GREATEST. THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE COLD FRONT BY EARLY AFTERNOON FROM NERN NEB THROUGH SERN MN TO MUCH OF THE WRN UPPER PENINSULA OF MI. ACTIVITY WILL THEN DEVELOP ESEWD ACROSS THE GREAT LAKES REGION AND TOWARD THE LOWER MO AND OH VALLEYS THIS EVENING/OVERNIGHT. MAINLY DEEP WNWLY WIND FIELDS SHOULD RESULT IN BOWING LINE SEGMENTS WITH DAMAGING WINDS THE PRIMARY THREAT. ...CENTRAL/ERN NY AND WRN VT... WEAK MID LEVEL IMPULSE AND ATTENDANT N-S ORIENTED SURFACE TROUGH ARE PROGGED TO MOVE EWD ACROSS THIS REGION TODAY INTO THIS EVENING. RESIDUAL MOISTURE ACROSS THIS REGION IS EXPECTED TO AID IN THE AIR MASS BECOMING MODERATELY UNSTABLE BY AFTERNOON AND SUPPORTING THUNDERSTORM DEVELOPMENT ALONG THE SURFACE TROUGH. THE INSTABILITY COMBINED WITH FAVORABLE DEEP LAYER SHEAR IS EXPECTED TO RESULT IN A SEVERE THREAT INTO THE EARLY EVENING. ...SRN MT SEWD TO NERN CO/NRN KS/NEB... ASCENT AHEAD OF THE NRN INTERMOUNTAIN SHORT WAVE TROUGH IS EXPECTED TO SPREAD ACROSS THE HIGHER TERRAIN OF SWRN MT/WRN WY BY EARLY AFTERNOON SUPPORTING THUNDERSTORM DEVELOPMENT. DESPITE SOMEWHAT DRY LOW LEVELS ACROSS SRN MT/WY...STEEP LAPSE RATES ARE EXPECTED TO SUPPORT MLCAPE VALUES AROUND 1000 J/KG. GREATER MOISTURE INTO THE CENTRAL PLAINS SHOULD RESULT IN A MODERATELY UNSTABLE AIR MASS FARTHER SE ALONG THE WRN EXTENT OF THE SURFACE BOUNDARY FROM ERN CO TO SRN NEB/NRN KS. THUNDERSTORMS ARE EXPECTED TO DEVELOP AND SPREAD ESEWD INTO THE NRN/CENTRAL HIGH PLAINS THIS AFTERNOON/EVENING WITH SUFFICIENT DEEP LAYER SHEAR RESULTING IN HAIL/STRONG WIND GUSTS. INCREASING UPSLOPE FLOW THIS EVENING INTO SERN MT MAY ALLOW STORMS TO PERSIST INTO THE OVERNIGHT PERIOD AS THE SHORT WAVE TROUGH APPROACHES THE WRN DAKOTAS...BUT DECREASING INSTABILITY SHOULD LIMIT THE SEVERE THREAT LATER TONIGHT. FARTHER SE...CONVERGENCE ALONG THE SURFACE BOUNDARY AND/OR UPSLOPE FLOW WILL SUPPORT THUNDERSTORM DEVELOPMENT FROM ERN CO EWD INTO NEB AND WRN/NRN KS. HAIL AND DAMAGING WINDS WILL ALSO BE A THREAT ACROSS THESE STATES. ...CENTRAL/ERN ORE INTO SRN ID/NWRN UT... A SHORT WAVE TROUGH APPROACHING ORE AND A SECOND IMPULSE APPROACHING THE NRN INTERMOUNTAIN REGION THIS AFTERNOON/EVENING SHOULD SUPPORT ISOLATED STRONG TO SEVERE STORMS FROM CENTRAL/ERN ORE INTO SRN ID AND NWRN UT. AIR MASS ACROSS THESE REGIONS IS EXPECTED TO BECOME MARGINALLY TO MODERATELY UNSTABLE WITH INCREASING DEEP LAYER SHEAR SUPPORTING STORM ORGANIZATION FOR A FEW SEVERE STORMS. ..PETERS/GUYER.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 12:52:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 08:52:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031251 SWODY1 SPC AC 031249 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 AM CDT MON JUL 03 2006 VALID 031300Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY INTO TONIGHT FROM WI/IA EWD TO PARTS OF PA/NY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FOR SRN MT AND NRN/ERN WY.... ...UPPER GREAT LAKES AREA THIS AFTERNOON/TONIGHT... PRIMARY SYNOPTIC FEATURE OF INTEREST THIS PERIOD WILL BE A STRONG MID LEVEL TROUGH MOVING ESEWD OVER ONTARIO AND THE UPPER GREAT LAKES. THIS WILL BE ACCOMPANIED BY A SURFACE CYCLONE INVOF JAMES BAY...AND AN ASSOCIATED COLD FRONT WILL MOVE SEWD FROM THE NRN PLAINS TO THE GREAT LAKES AND CENTRAL PLAINS BY EARLY TUESDAY. LOW-LEVEL MOISTENING/DESTABILIZATION IS EXPECTED TODAY ACROSS THE WI AREA IN ADVANCE OF THE COLD FRONT AND IN THE WAKE OF MORNING CONVECTION OVER NRN IL. THE NET RESULT SHOULD BE AFTERNOON MLCAPE VALUES OF 1500-2500 J/KG...BASED ON BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S AND TEMPERATURES OF 85-90 F. DEBRIS CLOUDINESS FROM THE WEAK CONVECTION OVER NW WI MAY SLOW SURFACE HEATING SOME TODAY ACROSS NRN WI AND UPPER MI...AND COULD LIMIT INSTABILITY. ADDITIONAL THUNDERSTORMS SHOULD DEVELOP ALONG THE COLD FRONT BY MID AFTERNOON ACROSS WI...AND POSSIBLE WRN UPPER MI IF CLOUD BREAKS OCCUR. THIS CONVECTION SHOULD THEN SPREAD ESEWD ACROSS LOWER MI AND THE NRN PORTIONS OF IL/INDIANA/OH TONIGHT. THE COMBINATION OF MODERATE INSTABILITY AND 0-6 KM VECTOR SHEAR ORIENTED ACROSS THE SURFACE FRONT MAY SUPPORT A FEW SUPERCELLS DURING THE AFTERNOON ACROSS THE WI AREA. CONVECTION WILL LIKELY EVOLVE INTO CLUSTERS/ LINE SEGMENTS WHILE MOVING SEWD OVERNIGHT...WITH A CONTINUED THREAT FOR DAMAGING GUSTS AND LARGE HAIL. ...OH VALLEY INTO PA/NY TODAY... SEVERAL SMALL SCALE WAVES ARE EMBEDDED IN THE SRN FRINGE OF THE WLYS...WITH THE MORE PRONOUNCED WAVES NOW MOVING EWD OVER ERN IA AND CENTRAL/ERN PA. AT THE SURFACE...A DIFFUSE BAROCLINIC ZONE EXTENDS FROM IA ACROSS LOWER MI TO NY...WITH A SECONDARY BOUNDARY RELATED TO OVERNIGHT/ONGOING CONVECTION FROM NRN IL TO SRN OH AND THE NRN CHESAPEAKE REGION. A FEW MULTICELL CLUSTERS MAY PERSIST DURING THE DAY ALONG THE SRN BOUNDARY...SUSTAINED BY SURFACE HEATING/DESTABILIZATION. OTHER STORMS MAY ALSO FORM BY MIDDAY/EARLY AFTERNOON ACROSS CENTRAL NY ALONG THE BAROCLINIC ZONE. DEEP LAYER WNWLY SHEAR AND MODEST INSTABILITY MAY BE SUFFICIENT FOR FEW ORGANIZED STORMS CAPABLE OF PRODUCING ISOLATED LARGE HAIL AND DAMAGING GUSTS. ...NRN ROCKIES AREA TODAY... A MID LEVEL SHORTWAVE TROUGH OVER ID THIS MORNING WILL CREST THE RIDGE AND MOVE ESEWD OVER MT/NRN WY BY LATER THIS AFTERNOON INTO EARLY TONIGHT. MODEST LOW-LEVEL MOISTURE /SURFACE DEWPOINTS IN THE LOW-MID 50S/ IS PRESENT ACROSS SRN MT AND ERN WY IN THE WAKE OF A FRONTAL PASSAGE...WHILE AFTERNOON TEMPERATURES SHOULD WARM INTO THE 80S WITH DAYTIME HEATING. WEAK-MODERATE INSTABILITY AND VERTICAL SHEAR ARE EXPECTED IN ADVANCE OF THE MID LEVEL WAVE...AND THUNDERSTORMS SHOULD FORM OVER THE HIGH TERRAIN OF SRN MT BY EARLY AFTERNOON. THE MORE INTENSE STORMS MAY DEVELOP SUPERCELL STRUCTURES AND BE CAPABLE OF PRODUCING LARGE HAIL AND GUSTY WINDS. ..THOMPSON/GUYER.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 16:24:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 12:24:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031623 SWODY1 SPC AC 031621 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1121 AM CDT MON JUL 03 2006 VALID 031630Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE MID MS VALLEY...EASTWARD ACROSS THE GREAT LAKES REGION INTO NY/PA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MT/WY/SD... ...WESTERN GREAT LAKES... BAND OF RELATIVELY STRONG WESTERLY FLOW ALOFT REMAINS TODAY FROM THE NORTHERN PLAINS...ACROSS THE GREAT LAKES...AND INTO NEW ENGLAND. WATER VAPOR IMAGERY SHOWS STRONG UPPER TROUGH ROTATING EASTWARD ACROSS NORTHWEST ONTARIO/MN TOWARD WI. SOUTHERLY LOW LEVEL WINDS AHEAD OF SYSTEM ACROSS WI WILL HELP TO TRANSPORT MOISTURE NORTHWARD WITH DEWPOINTS EXPECTED TO BE IN THE MID 60S THIS AFTERNOON. CLOUDS ARE SLOWLY DISSIPATING OVER THIS REGION AS WELL...WHICH SHOULD RESULT IN AFTERNOON MLCAPE VALUES OVER 1500 J/KG. PRESENT INDICATIONS ARE THAT SCATTERED THUNDERSTORMS WILL INTENSIFY THIS AFTERNOON ALONG APPROACHING COLD FRONT ACROSS WI...THEN TRACK EASTWARD ACROSS LAKE MI INTO LOWER MI. VERTICAL SHEAR PROFILES APPEAR FAVORABLE FOR A FEW SUPERCELLS CAPABLE OF DAMAGING WINDS AND HAIL. DESPITE WEAK LOW LEVEL WIND SPEEDS...BACKED FLOW IMMEDIATELY NORTH OF SURFACE BOUNDARY COULD POSE A RISK OF AN ISOLATED TORNADO OVER SOUTHEAST WI/NORTHERN IL THIS AFTERNOON AS WELL. SOUTHERN EXTENT OF THESE STORMS OVER SOUTHERN WI/EASTERN IA WILL LIKELY ORGANIZE AND PROPAGATE EASTWARD ALONG/JUST NORTH OF WEAK SURFACE BOUNDARY ACROSS NORTHERN IL INTO NORTHERN IND/SOUTHERN LOWER MI. HIGH SURFACE DEWPOINT VALUES POOLED ALONG THIS AXIS...COUPLED WITH STRONG WESTERLY FLOW ALOFT...SUGGEST THE POTENTIAL FOR A MORE CONCENTRATED AREA OF SEVERE STORMS THIS EVENING. EASTERN EXTENT OF SEVERE THREAT COULD REACH INTO PARTS OF EASTERN OH OVERNIGHT...DEPENDING ON THE EVOLUTION/ORGANIZATION OF MCS. ...NY/PA/NJ... INCREASING CU FIELD IS NOTED ON VISIBLE SATELLITE IMAGERY ACROSS THIS REGION TODAY. ISOLATED THUNDERSTORMS ARE LIKELY TO FORM DURING THE AFTERNOON...WITH SUFFICIENT INSTABILITY AND VERTICAL SHEAR FOR DAMAGING WINDS AND HAIL IN STRONGER CELLS. PLEASE REFER TO MESOSCALE DISCUSSION NUMBER 1425 FOR FURTHER DETAILS. ...MT/WY... AMPLE LOW/MID LEVEL MOISTURE IS PRESENT OVER SOUTHERN MT/NORTHERN WY TODAY...WHERE STRONG DAYTIME HEATING SHOULD RESULT IN MODERATE INSTABILITY OVER THE MOUNTAINS. SCATTERED AFTERNOON THUNDERSTORMS ARE EXPECTED THROUGHOUT THIS REGION...WITH ISOLATED CELLS CAPABLE OF DAMAGING WINDS AND HAIL. VERTICAL SHEAR IS RATHER WEAK IN THIS AREA...SUGGESTING SEVERE THREAT MAY BE LOCALIZED. ..HART/TAYLOR.. 07/03/2006  From swody1 at goshenarc.org Mon Jul 3 19:31:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 15:31:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 031930 SWODY1 SPC AC 031929 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0229 PM CDT MON JUL 03 2006 VALID 032000Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VALLEY EWD INTO NY STATE AND SWD INTO VA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN ROCKIES... ...UPPER MS VALLEY/GREAT LAKES... WATER VAPOR IMAGERY SHOWS AN UPPER LOW MOVING SLOWLY EWD ACROSS NRN ONTARIO WITH TRAILING SHORT WAVE TROUGH MOVING SEWD ACROSS THE UPPER MS VALLEY. ASSOCIATED SURFACE COLD FRONT FROM LAKE SUPERIOR ACROSS NWRN WI/SWRN IA/NRN KS WILL CONTINUE MOVING EWD...REACHING AN ERN LAKE SUPERIOR/SRN WI/NWRN MO LINE THIS EVENING AND SWRN ONTARIO TO CENTRAL MO BY 04/12Z. IN THE WARM SECTOR...A BAND OF ELEVATED CONVECTION FROM SRN IA ACROSS NRN IL/NRN IND HAS GENERATED A DIFFERENTIAL HEATING BOUNDARY ALONG ITS SRN EDGE...WHICH IS EXPECTED TO PROVIDE AN ADDITIONAL FOCUS FOR STRONG/SEVERE CONVECTION THIS AFTERNOON AND EVENING. PORTIONS OF THE WARM SECTOR FROM WI INTO PARTS OF IA/IL/IN HAS BECOME MODERATELY UNSTABLE WITH MLCAPE OF 1500-2500 J/KG...IN PART DUE TO HIGHER DEW POINT AXIS FROM IA EWD INTO NRN IN. LATEST VISIBLE IMAGERY SHOWS PRE-COLD FRONTAL CU FIELD BECOMING INCREASINGLY ENHANCED FROM NWRN WI INTO IA WITH STRONG THUNDERSTORMS CURRENTLY DEVELOPING OVER PARTS OF IA. THUNDERSTORMS WILL CONTINUE TO DEVELOP AND INTENSIFY ALONG/AHEAD OF THE COLD FRONT THIS AFTERNOON AS MID/UPPER LEVEL JET STREAK MOVES EWD ACROSS THE UPPER GREAT LAKES...PROVIDING STRONG DEEP LAYER SHEAR /35-50 KT EFFECTIVE SHEAR/ SUPPORTIVE OF SEVERE STORMS...INCLUDING POTENTIAL FOR A FEW SUPERCELLS. THIS ACTIVITY MAY BECOME INCREASINGLY ORGANIZED INTO ONE OR MORE FORWARD PROPAGATING MCS/S THIS EVENING...WHICH WOULD LIKELY SPREAD EWD ACROSS PARTS OF WI/NRN IL/LOWER MI/NRN IN AND POSSIBLY OH TONIGHT WITH THREAT FOR MORE CONCENTRATED REGION OF DAMAGING WIND GUSTS AND OCCASIONAL HAIL. ...LOWER GREAT LAKES INTO MID ATLANTIC STATES... A FEW STRONG/SEVERE STORMS HAVE DEVELOPED FROM NORTH OF LAKE ONTARIO SEWD ACROSS NY STATE...WITHIN INSTABILITY AXIS WHERE MLCAPE IS 1000-1500 J/KG. FLOW ALOFT IS MODERATELY STRONG WITH 500 MB WINDS OF 30-40 KT WHICH IS RESULTING IN SUFFICIENT VERTICAL SHEAR TO AID STORM ORGANIZATION. THIS ACTIVITY IS EXPECTED TO SPREAD EWD/SEWD THROUGH THE EVENING HOURS WITH THREAT FOR DAMAGING WINDS AND HAIL. ...SRN VA AREA... A BAND OF STRONG/SEVERE STORMS IS MOVING EWD/SEWD INTO PARTS OF SRN VA...ALONG SRN EDGE OF MODEST NWLY FLOW ALOFT. CLEAR SKIES AHEAD OF THIS BAND ARE PROMOTING STRONG HEATING/CONTINUED DESTABILIZATION WITH MLCAPE GREATER THAN 1500 J/KG. STEEP LOW LEVEL LAPSE RATES WILL ENHANCE DOWNDRAFT STRENGTH WITH THREAT FOR DAMAGING WIND GUSTS AND HAIL WITH STRONGER CELLS. ...NRN ROCKIES AREA... WATER VAPOR IMAGERY SHOWS A VORTICITY MAX MOVING EWD OVER MT WHICH IS GENERATING A FEW THUNDERSTORMS OVER THE MOUNTAINS OF MT AND NRN WY. STEEP LAPSE RATES AND MODERATE WLY MID LEVEL FLOW SUGGEST THE POSSIBILITY OF A FEW STRONG/SEVERE STORMS THIS AFTERNOON AND EVENING CAPABLE OF PRODUCING A FEW DAMAGING MICROBURSTS AND ISOLATED LARGE HAIL. ..WEISS.. 07/03/2006  From swody1 at goshenarc.org Tue Jul 4 01:00:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 03 Jul 2006 21:00:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040059 SWODY1 SPC AC 040057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT MON JUL 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE GREAT LAKES/MIDWEST INTO OH VALLEY... ...SYNOPSIS... CLOSED UPPER LOW WILL CONTINUE TO MOVE ESEWD ACROSS NRN ONTARIO WITH 30-40 METER HEIGHT FALLS EXPECTED OVER THE GREAT LAKES/OH VALLEY REGION OVERNIGHT. BROAD CYCLONIC FLOW REGIME WILL BE MAINTAINED FROM THE UPPER MS VALLEY THROUGH THE GREAT LAKES/OH VALLEY TO NERN STATES. STRONGER WLY MID LEVEL WINDS /40 KT/ AND STRENGTHENING WSWLY LLJ /35-40 KT/ EXPECTED FROM THE MIDWEST THROUGH THE OH VALLEY. ...GREAT LAKES/MIDWEST INTO OH VALLEY... EARLY EVENING SURFACE ANALYSIS SHOWED A WAVY STATIONARY BOUNDARY EXTENDING FROM OH WNWWD TO NRN IL...AND THEN SWWD INTO SERN IA TO SWRN KS. A COLD FRONT EXTENDING FROM THE ERN U.P. OF MI SWWD THROUGH CENTRAL WI TO NRN IA AND GENERALLY BISECTING NEB FROM NE-SW WILL CONTINUE TO ADVANCE ESE OVERNIGHT AND SHOULD REACH A LINE FROM SRN LOWER MI TO THE IA/MO BORDER BY 12Z TUESDAY. CURRENT OBJECTIVE ANALYSIS INDICATED A VERY UNSTABLE AIR MASS ACROSS ERN IA/SRN WI/NRN IL...WITH MUCH OF THE AIR MASS AHEAD OF THE COLD FRONT AND ALONG THE STATIONARY BOUNDARY EXPECTED TO REMAIN MODERATELY UNSTABLE THROUGH 06Z. INCREASING WNWLY MID LEVEL WINDS WILL MAINTAIN STRONG EFFECTIVE BULK SHEAR VALUES THIS EVENING/OVERNIGHT SUPPORTING ADDITIONAL ORGANIZED STRONG TO SEVERE STORMS ALONG THE PROGRESSIVE COLD FRONT WITH HAIL/STRONG WIND GUSTS THE PRIMARY THREATS. WATER VAPOR IMAGERY INDICATED SEVERAL EMBEDDED IMPULSES TRANSLATING EWD FROM THE LOWER MO VALLEY/MIDWEST THROUGH THE OH VALLEY WITH ONE SUCH FEATURE CURRENTLY LOCATED OVER SRN WI/NRN IL. ASCENT AHEAD OF THIS IMPULSE COMBINED WITH DESTABILIZATION/LOW LEVEL ASCENT ALONG A STRENGTHENING SWLY LLJ OVER IL/IND THIS EVENING SHOULD AID IN AN INCREASE IN THUNDERSTORMS ALONG THE STATIONARY BOUNDARY. THIS TREND IS CURRENTLY INDICATED BY REGIONAL RADARS FROM CENTRAL IL INTO NWRN IND WITH STRONG WIND GUSTS/HAIL AND AN ISOLATED TORNADO THREAT POSSIBLE. THIS LLJ SHOULD VEER TO WLY OVERNIGHT AS IT TRANSLATES EWD INTO THE CENTRAL/UPPER OH VALLEY SUPPORTING A CONTINUED THREAT FOR DAMAGING WINDS EWD INTO OH. ...NRN/CENTRAL HIGH PLAINS... SHORT WAVE TROUGH...CURRENTLY LOCATED OVER CENTRAL MT/NRN WY WILL CONTINUE TO ADVANCE EWD REACHING THE WRN DAKOTAS BY 12Z TUESDAY. ASCENT AHEAD OF THIS FEATURE COMBINED WITH PROGGED INCREASE IN UPSLOPE FLOW INTO SERN MT/ERN WY OVERNIGHT SUGGEST SCATTERED THUNDERSTORMS SHOULD PERSIST AT LEAST THROUGH THE EVENING. EFFECTIVE BULK SHEAR VALUES WILL REMAIN SUFFICIENT FOR ORGANIZED STORMS...BUT WEAK INSTABILITY SHOULD CONTINUE TO LIMIT THE OVERALL SEVERE COVERAGE. ..PETERS.. 07/04/2006  From swody1 at goshenarc.org Tue Jul 4 05:58:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 04 Jul 2006 01:58:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040557 SWODY1 SPC AC 040555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT TUE JUL 04 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NERN AND MID ATLANTIC STATES WWD INTO THE OH VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN WY/SWRN SD/WRN NEB... ...SYNOPSIS... CLOSED UPPER LOW OVER NRN ONTARIO AND ATTENDANT TROUGH EXTENDING ACROSS THE GREAT LAKES WILL MOVE SLOWLY ESEWD WITH BROAD CYCLONIC FLOW CONTINUING FROM THE UPPER MS VALLEY THROUGH THE GREAT LAKES/OH VALLEY REGION INTO THE MID ATLANTIC/NERN STATES. AMPLIFICATION OF GREAT LAKES TROUGH IS EXPECTED LATER TODAY/TONIGHT AS AN UPSTREAM SHORT WAVE TROUGH TRACKS SEWD TOWARD THE WRN GREAT LAKES/MIDWEST AND UPPER RIDGE BUILDS EWD OVER THE NRN HIGH PLAINS/CANADIAN PRAIRIE PROVINCES. MEANWHILE...A COUPLE OF MID LEVEL IMPULSES NOW LOCATED OVER THE ERN PACIFIC /WEST OF CA/ WILL TRACK NNELY WITHIN ERN PERIPHERY OF NERN PACIFIC CLOSED LOW CROSSING THE PACIFIC NORTHWEST THIS FORECAST PERIOD. ...NERN/MID ATLANTIC STATES WWD ACROSS THE OH VALLEY... AT THE SURFACE...A PRE-FRONTAL TROUGH IS EXPECTED TO MOVE SWD ACROSS THE OH VALLEY AND EWD INTO NEW ENGLAND TODAY FOLLOWED BY A COLD FRONT SPREADING EWD THROUGH ERN CANADA AND SEWD ACROSS THE LOWER GREAT LAKES AND MID MS VALLEY. THE COLD FRONT SHOULD EXTEND FROM NEW ENGLAND SWWD THROUGH THE OH VALLEY TO THE SRN PLAINS BY 12Z WEDNESDAY. THUNDERSTORMS SHOULD BE ONGOING AT 12Z TODAY FROM THE MID MS VALLEY TO PARTS OF THE LOWER GREAT LAKES REGION. SURFACE HEATING IS EXPECTED ALONG/S OF THE PRE-FRONTAL TROUGH...AND ALSO WITHIN A RATHER NARROW ZONE ACROSS THE SRN GREAT LAKES REGION IN THE WAKE OF THE MORNING ACTIVITY AND AHEAD OF THE COLD FRONT. DESPITE MODEST LAPSE RATES...THE SURFACE HEATING WITHIN A MOIST AIR MASS WILL RESULT IN MODERATE INSTABILITY. DEEP WSWLY WINDS AT 30-40 KT WILL SUPPORT SUFFICIENT DEEP LAYER SHEAR FOR ORGANIZED STORMS WITHIN THE SLIGHT RISK AREA. STRONG TO SEVERE STORMS SHOULD BE FOCUSED ALONG THE PRE-FRONTAL TROUGH FROM SRN IND/SRN OH TO THE MID ATLANTIC STATES AND NEW ENGLAND THROUGH THE AFTERNOON/EARLY EVENING. THE POTENTIAL FOR SEVERE STORMS IS ALSO EXPECTED ALONG THE PROGRESSIVE COLD FRONT FROM THE LOWER GREAT LAKES/OH VALLEY TO UPSTATE NY/NRN NEW ENGLAND. UNI-DIRECTIONAL TROPOSPHERIC WINDS WITH GENERALLY STRAIGHT HODOGRAPHS SUGGESTS LINE SEGMENTS WITH DAMAGING WINDS SHOULD BE THE PRIMARY THREAT...THOUGH SPLITTING STORMS WILL BE POSSIBLE. ...ERN WY INTO WRN PARTS OF SD/NEB... WEAK MID LEVEL IMPULSES CURRENTLY MOVING ENEWD THROUGH THE NRN INTERMOUNTAIN WEST PER WATER VAPOR IMAGERY ARE PROGGED TO TRACK SEWD ACROSS THE NRN/CENTRAL HIGH PLAINS THIS AFTERNOON. ESELY LOW LEVEL FLOW PROGGED ACROSS THIS REGION AS SURFACE HIGH PRESSURE BUILDS SEWD THROUGH THE MID MO VALLEY WILL ALLOW GREATER MOISTURE TO RETURN NWWD INTO WRN NEB/ERN WY. THIS MOISTURE WILL BE LOCATED BENEATH ERN EXTENT OF STEEP LAPSE RATES BY PEAK HEATING RESULTING IN MODERATE INSTABILITY. MODEST NWLY MID LEVEL WINDS /20-25 KT/ EXPECTED ATOP THE ESELY LOW LEVEL FLOW WILL PROVIDE FAVORABLE DEEP LAYER SHEAR /30-40 KT/ FOR SUPERCELLS WITH HAIL AND DAMAGING WIND GUSTS. THUNDERSTORMS SHOULD INITIALLY DEVELOP ALONG THE HIGHER TERRAIN OF ERN WY/SWRN SD...AND THEN DEVELOP SEWD INTO THE HIGH PLAINS. ...CENTRAL-ERN WA/NRN ORE/ID PANHANDLE... SLY MID LEVEL WINDS ARE PROGGED TO STRENGTHEN ACROSS THE PACIFIC NORTHWEST THIS FORECAST PERIOD AS THE NERN PACIFIC LOW MOVES SLOWLY TO THE ESE AND A COUPLE OF SHORT WAVE TROUGHS TRACK NNEWD ACROSS THIS REGION. PLUME OF MID LEVEL MOISTURE LOCATED WITHIN SSWLY FLOW ALOFT COMBINED WITH STEEP LAPSE RATES AND ASCENT AHEAD OF LEAD SHORT WAVE TROUGH ARE EXPECTED TO SUPPORT THE POTENTIAL FOR HIGH BASED THUNDERSTORMS THIS AFTERNOON INTO THE EVENING. ALTHOUGH DEEP LAYER SHEAR SHOULD INCREASE...MARGINAL INSTABILITY /MLCAPE 500-1000 J/KG/ IS EXPECTED TO LIMIT THE OVERALL SEVERE THREAT. STEEP LAPSE RATES AND DEEP WELL MIXED BOUNDARY LAYER /INVERTED-V THERMODYNAMIC PROFILES/ SUGGESTS THREAT FOR ISOLATED MICROBURSTS AND POSSIBLE HAIL. ..PETERS/GUYER.. 07/04/2006  From swody1 at goshenarc.org Mon Jul 10 05:58:08 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 01:58:08 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100556 SWODY1 SPC AC 100554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT MON JUL 10 2006 VALID 101200Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER OH VALLEY AND NRN APPALACHIANS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SRN PLAINS...CNTRL PLAINS AND MID-MS VALLEY... ...UPPER OH VALLEY/NRN APPALACHIANS... A SHORTWAVE TROUGH CURRENTLY OVER THE NRN APPALACHIAN MTNS WILL LIFT NEWD THIS MORNING AS ANOTHER GREAT LAKES SHORTWAVE MOVES INTO THE NERN U.S. THIS AFTERNOON. AT THE SFC...A COLD FRONT WILL APPROACH THE REGION TODAY WITH DEWPOINTS AHEAD OF THE BOUNDARY REMAINING NEAR 60 F ACROSS MUCH OF THE NRN APPALACHIAN MTNS. THIS SHOULD ALLOW POCKETS OF MODERATE INSTABILITY TO DEVELOP AS TEMPS WARM IN THE LATE MORNING. THE INCREASING LARGE-SCALE ASCENT AS THE UPPER-TROUGH APPROACHES SHOULD RESULT IN SCATTERED THUNDERSTORM DEVELOPMENT ACROSS NRN NEW ENGLAND...WRN NY...WRN PA AND NRN OH BY EARLY AFTERNOON. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW THE STRONGEST SHEAR PROFILES ACROSS WRN NY...PA AND NE OH ASSOCIATED WITH A 40 KT MID-LEVEL JET. THIS COMBINED WITH THE INSTABILITY SHOULD BE SUFFICIENT FOR SEVERE MULTICELL LINE SEGMENTS AND PERHAPS A FEW SUPERCELLS THIS AFTERNOON. COLD AIR ALOFT ASSOCIATED WITH THE UPPER TROUGH AND STEEP LOW-LEVEL LAPSE RATES SHOULD PROMOTE LARGE HAIL AND ISOLATED WIND DAMAGE WITH THE STRONGER CELLS. ...SRN AND CNTRL PLAINS/MID-MS VALLEY... AN UPPER-LEVEL TROUGH CURRENTLY OVER THE HIGH PLAINS WILL MOVE EWD INTO THE CNTRL PLAINS TODAY. A LARGE COMPLEX OF THUNDERSTORMS ONGOING AT THE BEGINNING OF THE PERIOD IS FORECAST TO MOVE NEWD INTO NE KS AND SE NEB DURING THE MORNING ALLOWING STRONG SFC HEATING TO TAKE PLACE IN THE WAKE OF THE MCS. SFC DEWPOINTS IN THE UPPER 60S F ACROSS SRN KS...NRN OK AND SWRN MO SHOULD RESULT IN AN AXIS OF MODERATE INSTABILITY BY EARLY AFTERNOON WITH A CAPPING INVERSION GRADUALLY WEAKENING ACROSS THE REGION. AS A RESULT...SCATTERED TO NUMEROUS THUNDERSTORMS SHOULD DEVELOP AND MOVE EWD DURING THE AFTERNOON AND EVENING. FORECAST SOUNDINGS ACROSS THE SLIGHT RISK AREA SHOW MODERATE VERTICAL SHEAR PROFILES ASSOCIATED WITH A 40-50 KT MID-LEVEL JET. THIS SHOULD BE SUFFICIENT FOR SEVERE MULTICELL LINE SEGMENTS AND ISOLATED SUPERCELLS. ALTHOUGH HAIL WILL BE POSSIBLE WITH THE STRONGER CELLS....THE WARM AIR ALOFT AND STEEP LOW-LEVEL LAPSE RATES SHOULD FAVOR WIND DAMAGE AS THE MAIN SEVERE THREAT. ...NRN ROCKIES... A WELL-DEFINED UPPER-LEVEL TROUGH CURRENTLY JUST OFF THE COAST OF BRITISH COLUMBIA AND WA IS FORECAST TO MOVE INLAND TODAY INTO THE NRN ROCKIES BY THIS AFTERNOON. THE STRONG LARGE-SCALE ASCENT AHEAD OF THE UPPER-TROUGH AND SFC HEATING IN THE HIGHER TERRAIN SHOULD ALLOW SCATTERED THUNDERSTORMS TO DEVELOP BY AFTERNOON. ALTHOUGH FORECAST SOUNDINGS SHOW STEEP LAPSE RATES AND MODERATE VERTICAL SHEAR...INSTABILITY MAY REMAIN WEAK DUE TO SFC DEWPOINTS MOSTLY IN THE 40S F. AS A RESULT...ANY SEVERE THREAT IS EXPECTED TO REMAIN MARGINAL THIS AFTERNOON WITH HAIL AND STRONG WIND GUSTS POSSIBLE WITH THE STRONGER CELLS. ..BROYLES.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 12:33:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 08:33:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101231 SWODY1 SPC AC 101229 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 AM CDT MON JUL 10 2006 VALID 101300Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF NORTHERN ROCKIES... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF OHIO...NEW YORK AND PENNSYLVANIA... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF CENTRAL AND SOUTHERN PLAINS... ...SYNOPSIS... WESTERLIES PRIMARILY ACROSS NRN CONUS WITH SEVERAL S/WVS THAT WILL BE FACTORS IN TODAYS CONVECTIVE ACTIVITY. COLD UPPER LOW NOW OPENING AND HEADING NEWD ACROSS SRN NEW ENGLAND AS NEXT UPPER LOW OVER LAKE HURON HEADS FOR WRN NY BY THIS EVENING. S/WV TROUGH WELL DEFINED ON WATER VAPOR IMAGERY NOW MOVING ONSHORE PAC NW WILL CROSS NRN ROCKIES LATER THIS AFTERNOON AND THEN LIFT NEWD INTO SRN ALBERTA OVERNIGHT AS ANOTHER IMPULSE APPROACHES WA COAST BY 12Z TUE. SOMEWHAT REMOVED FROM PRIMARY WLYS A WEAK MID LEVEL TROUGH CONTINUES SLOWLY EWD ACROSS CENTRAL PLAINS TODAY. WEAK COOL FRONT ACROSS SWRN ONTARIO WSWWD TO SRN IA INTO SRN NEB WILL DRIFT SEWD A LITTLE TODAY WITH SLOW WEAKENING. ...NRN ROCKIES... PERSISTENT OVERNIGHT LIGHTNING NERN OREGON NWD REFLECTS BOTH MOISTURE AND AVAILABLE INSTABILITY IN ADVANCE OF S/WV TROUGH THAT WILL BE CROSSING NRN ROCKIES TODAY. WITH 35-40KT OF DEEP LAYER SHEAR AND LAPSE RATES IN EXCESS OF 8 C/KM...PARAMETERS WILL BE FAVORABLE FOR BOTH MARGINALLY SEVERE HAIL AND DAMAGING WIND GUSTS AS STORMS INTENSIFY OVER HIGHER TERRAIN AHEAD OF TROUGH BY EARLY AFTERNOON. THEREFORE HAVE ADDED A SLIGHT RISK OVER AND W OF MTNS IN PRIMARILY MT. FURTHER E THE DOWNSLOPE FLOW WILL LIMIT BOTH MOISTURE AND INSTABILITY...THUS SEVERE POTENTIAL WILL DECREASE EWD OVER THE PLAINS THIS EVENING. ...NERN U.S... WHILE ISOLATED STRONG/SEVERE STORMS POSSIBLE THRU EARLY THIS AFTERNOON ASSOCIATED WITH UPPER LOW LIFTING NEWD ACROSS SRN NEW ENGLAND...PRIMARY SEVERE THREAT TODAY WILL BE WITH NEXT SYSTEM APPROACHING WRN NY/PA THIS AFTERNOON. COOL AIR ALOFT AND STEEP LAPSE RATES WITH WEAKENING UPPER LOW NOW MOVING ACROSS SRN NH POSES MAINLY A MARGINAL HAIL THREAT BEFORE MOVING OFFSHORE. SUFFICIENT HEATING SHOULD OCCUR THIS AM AHEAD OF FRONTAL ZONE WRN NY/PA TO ALLOW AIR MASS TO DESTABILIZE FOR A SEVERE THREAT GIVEN THE UPPER SUPPORT AND SHEAR THAT WILL BE PROVIDED BY THE APPROACHING TROUGH NOW OVER LH. WITH 30-35KT OF SHEAR AND MLCAPES TO AROUND 1000 J/KG STORMS WILL DEVELOP INTO CLUSTER AND LINE SEGMENTS BY EARLY/MID AFTERNOON WITH ASSOCIATED WIND AND HAIL THREAT. STORMS WILL SPREAD EWD PRIOR TO WEAKENING TO BELOW SVR LEVELS THIS EVENING OVER ERN NY/PA. ...CENTRAL/SRN PLAINS... AIR MASS IS NOW VERY MOIST AHEAD OF WEAK TROUGH MOVING ACROSS CENTRAL PLAINS AS NEAR 70F DEWPOINTS HAVE SPREAD NWD INTO SRN KS/SWRN MO. WITH RATHER WEAK MID LEVEL LAPSE RATES AND WARM TEMPERATURES ALOFT...PRIMARY SEVERE THREAT EXPECTED TO BE CONFINED TO WET MICRO BURSTS WHERE STORMS CAN DEVELOP IN AREAS OF GREATEST AFTERNOON HEATING AND DESTABILIZATION. STRONGEST STORMS WILL MOST LIKELY BE FOCUSED VICINITY OUTFLOW BOUNDARIES FROM THIS MORNINGS ACTIVITY. BOUNDARIES SHOULD BE LOCATED VICINITY KS/OK BORDER INTO SWRN MO. WITH SURFACE TEMPERATURES WARMING THRU THE 90S ACROSS MUCH OF OK...MLCAPES WILL CLIMB ABOVE 2000 J/KG S OF BOUNDARIES. THE 25-30KT OF SHEAR ASSOCIATED WITH THE UPPER TROUGH WILL BE SUFFICIENT FOR A FEW SEVERE STORMS WITH WET DOWNBURSTS THE PRIMARY THREAT GIVEN THE VERY WARM 500 MB TEMPERATURES AROUND -5C. ..HALES/BRIGHT.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 16:18:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 12:18:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101615 SWODY1 SPC AC 101613 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1113 AM CDT MON JUL 10 2006 VALID 101630Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON FOR ERN OH/WRN PA/WRN NY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS MAINE.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS WRN MT.... ...OH/WRN PA/WRN NY TODAY... A COMPACT MID LEVEL TROUGH IS MOVING ESEWD OVER SWRN ONTARIO TOWARD NE OH/NW PA/WRN NY. THIS MID LEVEL WAVE IS ACCOMPANIED BY A SURFACE LOW OVER SWRN ONTARIO...AND A COLD FRONT EXTENDING WSWWD ACROSS NW OH AND NRN INDIANA. DEBRIS CLOUDS ASSOCIATED WITH ONGOING CONVECTION OVER NE OH/NW PA WILL TEND TO OVERSPREAD WRN NY AND MAY LIMIT DESTABILIZATION THIS AFTERNOON. FARTHER S/SW...STRONGER SURFACE HEATING AND BOUNDARY LAYER DEWPOINTS IN LOW-MID 60S WILL CONTRIBUTE TO MLCAPE VALUES OF 1000-1500 J/KG THIS AFTERNOON ACROSS OH/WRN PA IN ADVANCE OF THE COLD FRONT. THIS INSTABILITY...COMBINED WITH MODEST /30-40 KT/ 0-6 KM SHEAR...SHOULD SUPPORT A FEW BOWING SEGMENTS AND POSSIBLY MARGINAL SUPERCELL STRUCTURES THIS AFTERNOON. DAMAGING GUSTS AND MARGINALLY SEVERE HAIL WILL BE THE PRIMARY SEVERE THREATS THROUGH LATE AFTERNOON. ...MAINE THIS AFTERNOON... A MID LEVEL WAVE IS EJECTING NEWD FROM NH TOWARD MAINE IN RESPONSE TO THE APPROACHING UPSTREAM TROUGH OVER THE LOWER GREAT LAKES. COOL MID LEVEL TEMPERATURES AND ROUGHLY 7 C/KM MID LEVEL LAPSE RATES OBSERVED IN THE 12Z GYX SOUNDING WILL COMBINE WITH DAYTIME HEATING AND LOWER 60S DEWPOINTS TO SUPPORT AFTERNOON MLCAPE VALUES APPROACHING 1000 J/KG. THOUGH VERTICAL SHEAR WILL REMAIN RATHER WEAK NEAR THE MID LEVEL WAVE AXIS...INSTABILITY SHOULD BE SUFFICIENT FOR A FEW STORMS WITH MARGINALLY SEVERE HAIL THIS AFTERNOON. ...WRN MT THIS AFTERNOON/EVENING... A PRONOUNCED MID LEVEL WAVE AND ASSOCIATED BAROCLINIC ZONE ARE MOVING EWD FROM WA TOWARD THE ID PANHANDLE AND WRN MT. THOUGH LOW-LEVEL MOISTURE IS LIMITED IN ADVANCE OF THIS SYSTEM...SURFACE HEATING WILL RESULT IN STEEP LOW-LEVEL LAPSE RATES AND MLCAPE VALUES NEAR 500 J/KG THIS AFTERNOON ACROSS WRN MT. CONVECTION SHOULD INCREASE BY EARLY AFTERNOON AS THE MID LEVEL TROUGH MOVES EWD OVER THE HIGHER TERRAIN OF WRN MT...WITH A BROKEN BAND OF THUNDERSTORMS EXPECTED TO PROGRESS EWD FROM WRN INTO CENTRAL MT AND WEAKEN LATER THIS EVENING. THE RELATIVELY GREATER INSTABILITY AND STRONGER LOW-MID LEVEL FLOW OVER WRN MT MAY SUPPORT A FEW DAMAGING GUSTS THIS AFTERNOON. ...KS/OK AREA THIS AFTERNOON... A SERIES OF WEAK MID LEVEL SPEED MAXIMA ARE MOVING SLOWLY EWD FROM NRN NM/SRN CO TOWARD KS AND NRN OK. REGIONAL SOUNDINGS REVEAL MOIST PROFILES AND MODEST INSTABILITY...AND SATELLITE IMAGERY SUGGESTS THAT ERN KS AND MUCH OF MO WILL REMAIN CLOUDY THROUGH MUCH OF THE AFTERNOON. THE MOIST/POOR LAPSE RATE PROFILES ARE NOT FAVORABLE FOR LARGE HAIL FORMATION OR WIDESPREAD DAMAGING OUTFLOW WINDS...THOUGH A FEW STRONG OUTFLOW GUSTS WILL BE POSSIBLE IN CONJUNCTION WITH STRONG SURFACE HEATING ON THE EDGE OF THE THICKER CLOUDS AND 25-30 KT FLOW NEAR 700 MB. ATTM...THE OVERALL SEVERE THREAT APPEARS TO BE TOO MARGINAL TO WARRANT A SLIGHT RISK. ..THOMPSON/JEWELL.. 07/10/2006  From swody1 at goshenarc.org Mon Jul 10 19:58:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 15:58:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101956 SWODY1 SPC AC 101955 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0255 PM CDT MON JUL 10 2006 VALID 102000Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTERNOON ACROSS PARTS OF THE LWR GREAT LAKES/UPR OH VLY.... ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTN ACROSS PARTS OF NRN NEW ENGLAND.... ...NEW ENGLAND... STRONGER MID/UPPER FORCING FOR UPWARD VERTICAL MOTION IS ALREADY SHIFTING TOWARD THE CANADIAN MARITIMES AS MID-LEVEL JET STREAK MIGRATES NORTHEAST OF COASTAL MAINE. HOWEVER...BENEATH MID-LEVEL COLD POCKET...WITH 500 MB TEMPERATURES AROUND -14C...AIR MASS REMAINS POTENTIALLY MODERATELY UNSTABLE ACROSS PARTS OF SOUTHERN/ EASTERN MAINE. THIS MAY STILL SUPPORT A FEW STRONG UPDRAFTS WITH LARGE HAIL POTENTIAL THROUGH LATE AFTERNOON...BUT...OVERALL... SEVERE THREAT SEEMS TO BE DIMINISHING. ...LOWER GREAT LAKES/UPPER OHIO VALLEY... STRONGEST DESTABILIZATION...WITH MIXED LAYER CAPE UP TO AROUND 1500 J/KG...HAS GENERALLY BEEN CONFINED TO THE WESTERN/SOUTHERN PERIPHERY OF DIGGING SHORT WAVE TROUGH...WHERE BETTER MOISTURE INFLUX EXISTS AND LOWER-LEVELS ARE A BIT WARMER. STRONG/ISOLATED SEVERE STORMS WITH LARGE HAIL AND GUSTY WINDS MAY PERSIST THROUGH THE REMAINDER OF THE AFTERNOON IN INSTABILITY AXIS AS IT SLOWLY SHIFTS SOUTH OF THE LOWER GREAT LAKES REGION. ACTIVITY IS EXPECTED TO WEAKEN/DIMINISH FAIRLY QUICKLY THIS EVENING ACROSS THE UPPER OHIO VALLEY...AS BOUNDARY LAYER COOLS. ...SOUTH CENTRAL PLAINS THROUGH THE OZARK PLATEAU... A BROAD TROUGH WITH EMBEDDED SMALL SCALE IMPULSES...WHICH HAS SUPPRESSED SUBTROPICAL RIDGING...CONTINUES TO SHIFT EAST OF THE CENTRAL ROCKIES INTO THE CENTRAL PLAINS. IN A CONDITIONALLY UNSTABLE ENVIRONMENT...LARGE-SCALE FORCING ASSOCIATED WITH THIS FEATURE WILL CONTINUE TO SUPPORT AN EXPANDING AREA OF CONVECTIVE DEVELOPMENT THROUGH THE REMAINDER OF THIS FORECAST PERIOD. STORMS WILL BECOME INCREASINGLY FOCUSED NEAR/JUST NORTH OF LOW-LEVEL THERMAL RIDGE AXIS ON ITS SOUTHERN PERIPHERY...WHERE MIXED LAYER CAPE OF 1000-2000 J/KG AND HIGH PRECIPITABLE WATER WILL SUPPORT VIGOROUS UPDRAFTS. LOCALLY HEAVY RAINFALL SEEMS PRIMARY THREAT...BUT SOME HAIL IS POSSIBLE IN STRONGEST CELLS. 25 TO 30 KT WESTERLY MID FLOW IN THE BASE OF THE UPPER TROUGH IS MOSTLY JUST NORTH OF ENVIRONMENT WITH VERY STEEP LOW-LEVEL LAPSE RATES. AND...WITH A SOUTHWESTERLY LOW-LEVEL JET NOT PROGGED TO DEVELOP/STRENGTHEN UNTIL AFTER DARK SOUTH OF THE KANSAS/OKLAHOMA BORDER INTO THE MISSOURI OZARKS...POTENTIAL FOR DAMAGING WINDS SEEMS LIKELY TO REMAIN LIMITED OR RATHER LOCALIZED. ...NORTHERN ROCKIES... A SIGNIFICANT SHORT WAVE TROUGH EMBEDDED WITHIN THE STRONGER WESTERLIES CONTINUES TO PROGRESS INLAND ACROSS BRITISH COLUMBIA AND THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES. THIS SYSTEM IS TAKING ON AN INCREASING NEGATIVE TILT...BUT STRONGEST FORCING/ DESTABILIZATION APPEARS TO BE COMING FOCUSED NORTH OF THE U.S. BORDER...ACROSS PARTS OF ALBERTA/SASKATCHEWAN. A FEW STRONG STORMS ARE POSSIBLE LATE THIS AFTERNOON/EVENING IN THE LEE OF THE NORTHERN ROCKIES...ACROSS PARTS OF WESTERN/CENTRAL MONTANA...BUT SEVERE POTENTIAL SEEMS MORE LIMITED/ISOLATED THAN EARLIER ANTICIPATED. **FOR MORE SPECIFIC DETAILS CONCERNING ONGOING OR MORE IMMINENT CONVECTIVE THREATS...PLEASE REFER TO LATEST SPC MESOSCALE DISCUSSIONS. ..KERR.. 07/10/2006  From swody1 at goshenarc.org Tue Jul 11 00:55:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 10 Jul 2006 20:55:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 110053 SWODY1 SPC AC 110051 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT MON JUL 10 2006 VALID 110100Z - 111200Z ...NO SVR TSTM AREAS FORECAST... ...UPPER OH VALLEY/NRN APPALACHIANS... LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LOW CENTERED OVER SWRN ONTARIO WITH THE LEADING EDGE OF LARGE-SCALE ASCENT MOVING EWD ACROSS WRN NY AND WRN PA. SCATTERED THUNDERSTORMS ARE ONGOING ACROSS THE REGION JUST AHEAD OF THE UPPER-TROUGH INCLUDING A LINE OF STRONG STORMS OVER WRN NY. ALTHOUGH SHEAR PROFILES REMAIN ADEQUATE FOR ORGANIZED STORMS...INSTABILITY SHOULD BEGIN TO STEADILY DECREASE OVER THE NEXT FEW HOURS ACROSS THE REGION. FOR THIS REASON...ANY MARGINAL SEVERE THREAT FOR HAIL AND STRONG WIND GUSTS SHOULD QUICKLY DIMINISH THIS EVENING. ...SRN PLAINS/OZARK PLATEAU... AN UPPER-TROUGH OVER THE SRN AND CNTRL PLAINS WILL CONTINUE TO MOVE EWD THIS EVENING SUPPORTING A LARGE MCS OVER OK...NW AR AND SRN MO. ALTHOUGH REGIONAL PROFILERS CURRENTLY SHOW VERTICAL SHEAR PROFILES ADEQUATE FOR SEVERE STORMS...INSTABILITY SHOULD CONTINUE TO DECREASE OVER THE NEXT FEW HOURS. FOR THIS REASON...THE POTENTIAL FOR WIND GUSTS WITH THE STRONGER CELLS EMBEDDED IN THE LINE SHOULD GRADUALLY DIMINISH. ..BROYLES.. 07/11/2006  From swody1 at goshenarc.org Tue Jul 11 05:57:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 11 Jul 2006 01:57:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 110556 SWODY1 SPC AC 110554 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1254 AM CDT TUE JUL 11 2006 VALID 111200Z - 121200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS...OZARK PLATEAU AND LOWER OH VALLEY... ...SRN PLAINS/OZARK PLATEAU/LOWER OH VALLEY... AN UPPER-LEVEL TROUGH OVER THE SRN PLAINS IS FORECAST TO MOVE VERY SLOWLY EWD TONIGHT INTO TUESDAY. AT THE SFC...A COLD FRONT WILL MOVE SWD ACROSS KS...MO AND IL DURING THE DAY WITH SFC DEWPOINTS SOUTH OF THE BOUNDARY IN THE UPPER 60S AND LOWER 70S F. THE HIGH SFC DEWPOINTS COUPLED WITH STRONG SFC HEATING WILL RESULT IN AN AXIS OF MODERATE INSTABILITY EXTENDING ENEWD FROM THE TX PANHANDLE ACROSS OK INTO SCNTRL MO AND CNTRL IL. AS THE CAP WEAKENS AND LOW-LEVEL CONVERGENCE INCREASES SOUTH OF THE FRONT...SCATTERED TO NUMEROUS THUNDERSTORMS SHOULD INITIATE IN THE EARLY AFTERNOON AND MOVE ESEWD ACROSS THE REGION. FORECAST SOUNDINGS TUESDAY AFTERNOON FROM THE SRN PLAINS TO THE LOWER OH VALLEY SHOW MAINLY UNIDIRECTIONAL WIND PROFILES WITH SUBSTANTIAL SPEED SHEAR IN THE LOWER TO MID-LEVELS. THIS SHOULD RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR SEVERE MULTICELL LINES AND POSSIBLY ISOLATED SUPERCELLS. WIND DAMAGE WILL BE MOST LIKELY WITH LINE SEGMENTS AS LOW-LEVEL LAPSE RATES STEEPEN SOUTH OF THE FRONT IN THE MID TO LATE AFTERNOON. THE WIND DAMAGE POTENTIAL MAY BECOME ENHANCED ACROSS PARTS OF THE SRN PLAINS WHERE FORECAST SOUNDINGS SHOW INVERTED-V THERMODYNAMIC PROFILES. LARGE HAIL WILL BE MOST LIKELY FROM CNTRL IL EXTENDING SWWD ACROSS MO INTO NRN OK WHERE MID-LEVEL TEMPS ARE FORECAST TO BE RELATIVELY COLDER THAN AREAS TO THE SOUTHWEST. ...NEW ENGLAND... LATEST WATER VAPOR IMAGERY SHOWS A WELL-DEFINED SHORTWAVE TROUGH OVER WRN NY AND CNTRL PA. THE TROUGH IS FORECAST TO MOVE ENEWD INTO NEW ENGLAND WITH STRONG LARGE-SCALE ASCENT SUPPORTING SCATTERED THUNDERSTORM DEVELOPMENT IN THE NRN APPALACHIAN MTNS THIS AFTERNOON. FORECAST SOUNDINGS THIS AFTERNOON IN NEW ENGLAND SHOW MODERATE VERTICAL SHEAR PROFILES FROM SRN MAINE SWD TO THE NEW YORK CITY AREA ASSOCIATED WITH A 40 KT MID-LEVEL JET. THIS SHOULD BE SUFFICIENT FOR ORGANIZED THUNDERSTORMS THIS AFTERNOON IF ENOUGH INSTABILITY DEVELOPS AHEAD OF THE TROUGH. HOWEVER...CLOUD COVER ASSOCIATED WITH THE UPPER-TROUGH MAY HAMPER DESTABILIZATION SOMEWHAT TODAY. AS A RESULT...ANY SEVERE THREAT THAT DEVELOPS IS EXPECTED TO REMAIN MARGINAL ATTM. ..BROYLES.. 07/11/2006  From swody1 at goshenarc.org Wed Jul 12 12:43:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 08:43:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121241 SWODY1 SPC AC 121239 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 AM CDT WED JUL 12 2006 VALID 121300Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF NERN U.S.... ...THERE IS A SLGT RISK OF SVR TSTMS MUCH OF MT AND ADJACENT HIGH PLAINS... ...SYNOPSIS... MID-SUMMER LARGE SCALE PATTERN OVER CONUS WITH STRONGER WLYS CONFINED TO NEAR CANADIAN BORDER. GREATER SEVERE THUNDERSTORM THREAT TODAY WILL BE ASSOCIATED WITH THE RATHER BROAD TROUGH AND ASSOCIATED WIND MAX MOVING ACROSS THE NERN U.S. AND A DEAMPLIFYING S/WV MOVING ACROSS NRN ROCKIES THIS AFTERNOON. ...NERN U.S... A VERY MOIST/TROPICAL-LIKE AIR MASS WILL SPREAD ACROSS NERN U.S. TODAY. SURFACE LOW LOCATED N OF DTW WAS ASSOCIATED WITH A TROUGH MOVING THRU GREAT LAKES AND FORECAST TO TRACK EWD ACROSS NY AND WRN NEW ENGLAND THIS AFTERNOON AND EVENING. SOUTH OF THE SURFACE LOW A BAND OF 30-40KT LOW THROUGH MID LEVEL FLOW WILL SPREAD EWD FROM UPPER OH VALLEY TO SRN NEW ENGLAND. EXTENSIVE CLOUDINESS WILL SLOW HEATING MUCH OF NERN U.S...HOWEVER SHEAR PROFILES WILL BECOME FAVORABLE FOR BOTH DEVELOPMENT OF CONVECTIVE LINE SEGMENTS AND LOW TOPPED SUPERCELLS NEAR AND SOUTH OF THE SURFACE LOW TRACK. GIVEN HIGH MOISTURE...EXPECT POCKETS OF SURFACE HEATING OCCURRING IN WAKE OF CURRENT LARGE AREA OF PCPN NOW MOVING EWD NY/PA TO ALLOW AN INCREASE IN MLCAPE TO 1500 J/KG...PARTICULARLY PA SWD. MODEL FORECAST SOUNDINGS INDICATE 20-30KT OF SFC-1KM SHEAR AND LCLS LESS THAN 1KM WILL SUPPORT TORNADOES LATER THIS AFTERNOON ACROSS PA AND INTO SERN NY IF SUFFICIENT INSTABILITY DEVELOPS. ADDITIONALLY...30-40KT STEERING FLOW SHOULD PROMOTE FORMATION OF SHORT LINE SEGMENTS WITH AN ENHANCED POTENTIAL FOR WIND DAMAGE FROM CENTRAL PA EWD INTO PARTS OF SRN NEW ENGLAND BY THIS EVENING. SRN LIMIT OF ANY ORGANIZED SEVERE THREAT WILL BE ALONG SRN FRINGE OF STRONGER MID LEVEL FLOW. LEE TROUGH CURRENTLY DELMARVA ALONG WITH HIGH THETA-E AIR MASS WILL PROVIDE SOME ENHANCEMENT OF SURFACE CONVERGENCE THIS AREA WHERE MLCAPES WITH SFC TEMPS AOA 90F COULD REACH TO AOA 2000 J/KG. THIS WILL INCREASE POTENTIAL FOR WET MICRO-BURSTS. ...MT AND WRN ND... AS STRONGER MID LEVEL FLOW SPREADS EWD WITH PASSAGE OF THE S/WV TROUGH HEADING EWD FROM OR/WA...POTENTIAL FOR SEVERE THUNDERSTORMS WILL INCREASE THIS AFTERNOON HIGHER TERRAIN CENTRAL MT. WHILE INSTABILITY/MOISTURE WILL BE SOMEWHAT LIMITED...THE STEEP LAPSE RATES COUPLED WITH SFC-6KM SHEAR OF 35-40KT WILL SUPPORT HIGH BASED MULTICELLULAR STORM DEVELOPMENT. PREDOMINANT THREAT WILL BE DAMAGING WINDS...HOWEVER MARGINALLY SEVERE HAIL IS ALSO LIKELY WITH STRONGER UPDRAFTS. ACTIVITY WILL SPREAD ACROSS NRN HIGH PLAINS INTO TONIGHT...WITH CONTINUING SEVERE POTENTIAL AFTER DARK. ..HALES/CARBIN.. 07/12/2006  From swody1 at goshenarc.org Wed Jul 12 16:18:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 12:18:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121615 SWODY1 SPC AC 121614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT WED JUL 12 2006 VALID 121630Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM THE OH VALLEY TO INTERIOR SRN NEW ENGLAND.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FOR MT AND WRN ND.... ...NY/PA TO NRN KY THROUGH THIS EVENING... A SURFACE LOW AND ASSOCIATED MID LEVEL WAVE OVER SWRN ONTARIO WILL MOVE EWD ACROSS CENTRAL NY THROUGH TONIGHT. VERY MOIST PROFILES ARE PRESENT IN ADVANCE OF THIS SYSTEM ACROSS PA/NY...WITH WIDESPREAD CLOUDS/RAINFALL ACROSS CENTRAL PA AND MUCH OF NY EXPECTED TO LIMIT SURFACE HEATING. HOWEVER...A FEW BREAKS IN THE CLOUDS ARE PRESENT OVER E/SE PA INVOF A WEAK LEE TROUGH...WITH LOWER 70 DEWPOINTS SPREADING NWD ACROSS THIS AREA. THIS RICH MOISTURE AND TEMPERATURES IN THE 70S ACROSS SRN NY AND AT LEAST MID 80S ERN PA/NJ WILL CONTRIBUTE TO AFTERNOON MLCAPE VALUES OF 500-1000 J/KG. THOUGH INSTABILITY WILL BE MARGINAL IN THE TROPICAL TYPE ENVIRONMENT...FORECAST WIND PROFILES SUGGEST THE POTENTIAL FOR SUPERCELLS GIVEN EFFECTIVE BULK SHEAR OF 30-40 KT AND 0-1 KM SRH IN EXCESS OF 200 M2/S2 ACROSS NE PA AND SE NY THIS AFTERNOON. THE MORE FOCUSED THREAT AREA SHOULD BE E OF THE LEE TROUGH AND ALONG THE SRN FRINGE OF THE THICKER CLOUDS THAT ARE REINFORCING A WEAK BOUNDARY ACROSS SRN NY/NE PA. CLOUD BREAKS TO THE S SHOULD ALLOW A FEW DISCRETE STORMS TO FORM IN THE LARGER AREA OF CONVECTION...AND A FEW TORNADOES MAY OCCUR GIVEN THE RICH LOW-LEVEL MOISTURE AND PRONOUNCED LOW-LEVEL SHEAR. FARTHER SW...REGIONAL SOUNDINGS AND VWP/S REVEAL A BELT OF 30-40 KT WSWLY FLOW IN THE 1-3 KM AGL LAYER FROM KY TO PA. MEANWHILE...SURFACE HEATING/DESTABILIZATION ALONG THE SERN FRINGE OF THE THICKER CLOUDS WILL ALLOW THE DEVELOPMENT OF MODERATE INSTABILITY THIS AFTERNOON. THE STEEPER LOW-LEVEL LAPSE RATES AND BELT OF STRONGER LOW-LEVEL FLOW SHOULD BE FAVORABLE FOR A FEW STORMS WITH DAMAGING OUTFLOW WINDS THIS AFTERNOON. ...NRN HIGH PLAINS THIS AFTERNOON/TONIGHT... A MID LEVEL SHORTWAVE TROUGH OVER ERN WA/ORE AND WRN ID THIS MORNING WILL EJECT ENEWD TOWARD ERN MT AND THE SRN PRAIRIE PROVINCES BY EARLY THURSDAY. IN ADVANCE OF THIS TROUGH...A SURFACE LOW NOW IN E CENTRAL MT SHOULD DEVELOP NEWD TOWARD SE SASKATCHEWAN...WHILE BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 60S SPREAD NWD ACROSS THE DAKOTAS. FARTHER W ACROSS MT...THE LOW-LEVELS ARE QUITE DRY ACCORDING THE SURFACE OBSERVATIONS AND 12Z SOUNDINGS. HIGH-BASED CONVECTION MAY MOVE EWD/NEWD OFF THE HIGHER TERRAIN OF SW MT THIS AFTERNOON AS THE MID LEVEL WAVE APPROACHES. DESPITE WEAK INSTABILITY...DEEP INVERTED-V PROFILES COULD SUPPORT A FEW DAMAGING GUSTS ACROSS SW/CENTRAL MT FROM MID-LATE AFTERNOON. OTHER THUNDERSTORMS MAY ALSO FORM THIS AFTERNOON ALONG THE LEE TROUGH ACROSS THE WRN DAKOTAS. INSTABILITY WILL BE SOMEWHAT STRONGER THIS AREA COMPARED TO MT GIVEN AFTERNOON BOUNDARY LAYER DEWPOINTS IN THE 50S...AND VERTICAL SHEAR SHOULD BECOME AT LEAST MARGINALLY FAVORABLE FOR ORGANIZED SEVERE STORMS AS LOW-MID LEVEL FLOW INCREASES IN ADVANCE OF THE MID LEVEL WAVE APPROACHING MT. ...TX PANHANDLE/WRN OK THIS AFTERNOON/EVENING... A WEAK MID LEVEL WAVE OVER THE NRN TX PANHANDLE WILL MOVE SLOWLY EWD TOWARD WRN OK. STRONG SURFACE HEATING IS EXPECTED ACROSS THE TX PANHANDLE IN THE WAKE OF SCATTERED EARLY MORNING CONVECTION...WITH THE STRONGER SURFACE HEATING IN OK ALONG AND S OF I-40. AFTERNOON TEMPERATURES OF 95-100 F WILL RESULT IN STEEP LOW-LEVEL LAPSE RATES AND MODERATE INSTABILITY...WHILE ROUGHLY 25 KT WLY/WNWLY MID LEVEL FLOW WILL PERSIST AROUND THE SRN PERIPHERY OF THE TX PANHANDLE WAVE. SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON...WITH THE POTENTIAL FOR SOME ORGANIZATION TO MULTICELL CLUSTERS. THE STRONGEST STORMS MAY PRODUCE LOCALLY STRONG/DAMAGING DOWNBURSTS AND MARGINALLY SEVERE HAIL. ..THOMPSON/GUYER.. 07/12/2006  From swody1 at goshenarc.org Wed Jul 12 20:03:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 16:03:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 121959 SWODY1 SPC AC 121958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT WED JUL 12 2006 VALID 122000Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS SRN PARTS OF THE OH VALLEY INTO THE MID ATLANTIC...NERN U.S. AND SRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN ROCKIES INTO THE NRN HIGH PLAINS... ...NERN U.S. THROUGH SRN NEW ENGLAND AREA... A WARM FRONT EXTENDS FROM SRN NEW ENGLAND WWD THROUGH CNTRL NY TO A SURFACE LOW OVER THE LOWER GREAT LAKES. RICH LOW LEVEL MOISTURE EXISTS NEAR AND S OF FRONT WITH DEWPOINTS NEAR 70. MOIST...TROPICAL DEEP LAYER PROFILES WITH WIDESPREAD CLOUDS AND POOR MID LEVEL LAPSE RATES HAVE RESULTED IN MARGINAL INSTABILITY. SOME BOUNDARY LAYER WARMING HAS DEVELOPED ALONG SRN EDGE OF THICKER CLOUD SHIELD FROM ERN PA THROUGH NJ AND EXTREME SRN NEW ENGLAND WITH MLCAPE FROM 500 TO 1000 J/KG. SHORTWAVE TROUGH AND ATTENDANT SURFACE LOW OVER THE GREAT LAKES WILL MIGRATE ENEWD ALONG THE LOW LEVEL BAROCLINIC ZONE TOWARD ENGLAND THIS AFTERNOON AND EVENING. AS THIS OCCURS A 40+ KT LOW LEVEL JET WILL STRENGTHEN NEWD INTO THE NERN U.S. AND SRN NEW ENGLAND WITH INCREASING LOW LEVEL SHEAR PROFILES. A FEW STORMS WITH SUPERCELL STRUCTURES HAVE ALREADY BEEN OBSERVED IN WARM SECTOR FROM NRN NJ INTO SERN NY AND SRN NEW ENGLAND. ADDITIONAL STORMS MAY DEVELOP THE REMAINDER OF THIS AFTERNOON INTO THE EVENING AS THE BOUNDARY LAYER CONTINUES TO DESTABILIZE. STRENGTHENING LOW LEVEL SHEAR WILL MAINTAIN A THREAT FOR A FEW SUPERCELLS WITH LOW LEVEL MESOCYCLONES AND ISOLATED TORNADOES INTO THE EARLY EVENING. ...SRN OH AND TN VALLEY THROUGH MID ATLANTIC AREAS... SEVERAL MULTICELL CLUSTERS CONTINUE DEVELOPING ALONG NUMEROUS OUTFLOW BOUNDARIES AND IN ASSOCIATION WITH REMNANT MCVS FROM PARTS OF TN...KY AND INTO WV AND NRN VA. THE ATMOSPHERE HAS BECOME MODERATELY UNSTABLE IN THESE AREAS OWING TO AMPLE SURFACE HEATING. PRIMARY THREAT WILL CONTINUE TO BE ISOLATED DAMAGING WIND GUSTS WITH THE STRONGER STORMS THROUGH EARLY EVENING. ...ERN ID...MT THROUGH WRN ND... SCATTERED STORMS ARE CURRENTLY DEVELOPING OVER THE HIGHER TERRAIN OF SWRN MT INTO SERN ID WITHIN ZONE OF ASCENT ACCOMPANYING A SHORTWAVE TROUGH ADVANCING EWD THROUGH THE NRN ROCKIES. ACTIVITY WILL BEGIN TO SPREAD EWD INTO THE HIGH PLAINS OF MT WHERE TEMPERATURES HAVE WARMED INTO THE 90S AND DEWPOINTS HAVE MIXED INTO THE 50S WITH RESULTING INVERTED-V BOUNDARY LAYER PROFILES AND STEEP LAPSE RATES. INSTABILITY IS SOMEWHAT LIMITED OWING TO THE MODEST LOW LEVEL MOISTURE. THIS SUGGESTS THE PRIMARY THREAT WILL BE ISOLATED DAMAGING WIND. HOWEVER MARGINALLY SEVERE HAIL COULD ALSO ACCOMPANY THE STRONGER STORMS. FARTHER EAST RICHER LOW LEVEL MOISTURE EXISTS ACROSS THE CNTRL DAKOTAS...BUT STRONG MIXING HAS RESULTED IN DEWPOINTS FALLING INTO THE 40S AND 50S OVER THE WRN DAKOTAS. A SURFACE BOUNDARY EXTENDS FROM WRN SD SWWD INTO ERN MT. A LEE TROUGH EXTENDS NWD THROUGH WRN SD INTO SWRN ND. STRONG HEATING AND MIXING WITH TEMPERATURES AROUND 100 HAS WEAKENED THE CAP IN THIS AREA...AND THUNDERSTORMS ARE IN THE PROCESS OF DEVELOPING ALONG THESE BOUNDARIES. INVERTED-V PROFILES WILL PROMOTE THE THREAT OF ISOLATED DAMAGING WIND WITH THIS ACTIVITY. MODERATE INSTABILITY AND VERY STEEP LAPSE RATES WILL ALSO SUPPORT A THREAT FOR HAIL. ...CNTRL PLAINS... REFER TO SWOMCD 1489. ..DIAL.. 07/12/2006  From swody1 at goshenarc.org Thu Jul 13 00:59:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 12 Jul 2006 20:59:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130058 SWODY1 SPC AC 130056 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 PM CDT WED JUL 12 2006 VALID 130100Z - 131200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF NEW ENGLAND AND THE MID-ATLANTIC... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE NRN PLAINS... ...MID-ATLANTIC/SRN NEW ENGLAND... LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE TROUGH OVER SWRN ONTARIO EXTENDING SSWWD INTO THE UPPER OH VALLEY. AHEAD OF THE TROUGH...LARGE-SCALE ASCENT ACROSS THE NEW ENGLAND AND MID-ATLANTIC STATES IS SUPPORTING SCATTERED STRONG THUNDERSTORMS. THE STRONGEST STORMS ARE LOCATED ALONG THE WRN EDGE OF MODERATE INSTABILITY ACROSS SERN PA. THE INSTABILITY SHOULD SUSTAIN STRONG UPDRAFTS ACROSS THE REGION FOR A FEW MORE HOURS. REGIONAL WSR-88D VWPS CURRENTLY SHOW 0-6 KM SHEAR VALUES AROUND 30 KT ACROSS NJ WHICH COMBINED WITH STRONG LOW-LEVEL FLOW ASSOCIATED WITH A 40-45 KT LOW-LEVEL JET OVER SRN PA SHOULD CONTINUE A THREAT FOR WIND DAMAGE WITH THE STRONGER CELLS. WIND DAMAGE AND POSSIBLY HAIL WILL BE MOST LIKELY WITH THE MORE-ORGANIZED MULTICELL LINE SEGMENTS. ...NRN PLAINS... WATER VAPOR AND RUC ANALYSIS SHOW SOUTHWEST FLOW IN PLACE ACROSS THE NRN PLAINS WITH A SHORTWAVE TROUGH EMBEDDED IN THE FLOW OVER THE WRN DAKOTAS. AN MCS IS CURRENTLY ONGOING JUST AHEAD OF THE SHORTWAVE WHERE ASCENT IS MAXIMIZED DUE TO LARGE-SCALE ASCENT AND LIFT ASSOCIATED WITH A 35-40 KT LOW-LEVEL JET. OBJECTIVE ANALYSIS CURRENTLY SHOWS AN AXIS OF MODERATE INSTABILITY EXISTS FROM CNTRL SD EXTENDING NNEWD ACROSS CNTRL ND INTO SRN MANITOBA WHERE MLCAPE VALUES RANGE FROM 1500-3000 J/KG. THE INSTABILITY SHOULD MAINTAIN STRONG UPDRAFTS AS STORMS DRIFT NEWD INTO NCNTRL ND THIS EVENING. MODERATE VERTICAL SHEAR AND STEEP MID-LEVEL LAPSE RATES EVIDENT ON FORECAST SOUNDINGS SHOULD CONTINUE A THREAT FOR LARGE HAIL WITH THE STRONGER CELLS. WIND DAMAGE WILL ALSO BE POSSIBLE WITH MULTICELL LINE SEGMENTS AS THE LOW-LEVEL JET INCREASES THIS EVENING. ...SRN PLAINS/OZARK PLATEAU... SEVERAL SMALL THUNDERSTORM CLUSTERS ARE ONGOING ACROSS THE SRN PLAINS AND OZARK PLATEAU. THE STRONGEST STORMS ARE LOCATED ALONG AN INSTABILITY AXIS FROM CNTRL KS EXTENDING SEWD INTO ERN OK AND WRN AR. ALTHOUGH REGIONAL PROFILES SHOW RELATIVELY WEAK WIND SHEAR PROFILES (0-6 KM SHEAR 10-20 KT)...MODERATE TO STRONG INSTABILITY AND STEEP LOW-LEVEL LAPSE RATES MAY BE SUFFICIENT FOR A MARGINAL WIND DAMAGE THREAT OVER THE NEXT FEW HOURS. ...ERN WA... A SMALL THUNDERSTORM COMPLEX IS CURRENTLY ONGOING IN ERN WA IN A REGION OF WIDESPREAD LARGE-SCALE ASCENT ASSOCIATED WITH A PACIFIC NORTHWEST UPPER-LEVEL TROUGH. OBJECTIVE ANALYSIS SHOWS AN AXIS OF INSTABILITY OVER ERN WA WITH MLCAPE VALUES AROUND 750 J/KG WITH STEEP LAPSE RATES EXCEEDING 8.5 C/KM. THIS ALONG WITH RELATIVELY COLD 500 MB TEMPS AROUND -15 C SHOULD BE FAVORABLE FOR HAIL OVER THE NEXT FEW HOURS. ..BROYLES.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 06:05:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 02:05:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 130602 SWODY1 SPC AC 130601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT THU JUL 13 2006 VALID 131200Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE GREAT PLAINS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF VA...WV AND NRN NC... ...GREAT PLAINS... A NRN ROCKIES UPPER-TROUGH IS FORECAST TO MOVE QUICKLY EWD ACROSS THE HIGH PLAINS INTO THE NRN AND CNTRL PLAINS THIS AFTERNOON. LARGE-SCALE ASCENT WILL RAPIDLY INCREASE ACROSS THE PLAINS WITH A LINE OF THUNDERSTORMS QUICKLY DEVELOPING ALONG THE WRN EDGE OF AN AXIS OF MODERATE TO STRONG INSTABILITY BY MID-AFTERNOON. FORECAST SOUNDINGS SHOW INCREASING VERTICAL SHEAR PROFILES AS A 40-50 KT MID-LEVEL JET NOSES INTO THE REGION. IN ADDITION...0-6 KM SHEAR VALUES BETWEEN 30 AND 40 KT AS SHOWN ON FORECAST SOUNDINGS SUGGEST SEVERE MULTICELL LINE SEGMENTS AND/OR SUPERCELLS WILL BE POSSIBLE AS STORMS INCREASE IN COVERAGE LATE THIS AFTERNOON. ALTHOUGH THE MODELS DIFFER CONCERNING THE SRN EXTENT OF A LINEAR MCS...THE WRF MODEL SEEMS REASONABLE DEVELOPING A LINE FROM ERN SD EXTENDING SWD ACROSS ERN NEB. LOW-LEVEL LAPSE RATES ARE FORECAST TO BE VERY STEEP (0-3 KM LAPSE RATES > 9.0 C/KM) WHICH WILL LIKELY ENHANCE THE WIND DAMAGE POTENTIAL. VERY STRONG WIND GUSTS WILL BE POSSIBLE WITH ANY BOWING SEGMENTS IN THE LINE. HAIL WILL ALSO BE LIKELY WITH THE STRONGER ELEMENTS IN THE LINE AND THE GREATEST POTENTIAL FOR LARGE HAIL SHOULD EXIST WITH SUPERCELLS THAT DEVELOP AHEAD OF OR EMBEDDED IN THE LINE. THE LINEAR MCS SHOULD MOVE ESEWD ACROSS THE SIOUX FALLS SD AND OMAHA NEB AREAS BY EARLY EVENING LIKELY REACHING WRN IA...NW MO AND NE KS BY LATE EVENING. A SEVERE THREAT MAY CONTINUE OVERNIGHT ESPECIALLY CONSIDERING STRONG INSTABILITY IS FORECAST TO BE IN PLACE THROUGH THIS EVENING. FURTHER SOUTH ACROSS SW KS...THE ERN TX PANHANDLE AND NW OK...THE MODELS FORECAST WEAKER LARGE-SCALE ASCENT AND A STRONGER CAPPING INVERSION THAN AREAS FURTHER NORTH WHICH SHOULD KEEP THUNDERSTORM COVERAGE MORE ISOLATED. ALTHOUGH THE HAIL POTENTIAL MAY BE LESS DUE TO THE WARMER AIR ALOFT...A POTENTIAL FOR WIND DAMAGE SHOULD STILL EXIST WITH THE STRONGER CELLS DUE TO STEEP LOW-LEVEL LAPSE RATES AND MODERATE VERTICAL SHEAR SHOWN ON FORECAST SOUNDINGS. ...VA/NC... WATER VAPOR IMAGERY CURRENTLY SHOWS A SHORTWAVE TROUGH OVER THE OH VALLEY WITH A NOTABLE DRY PUNCH ADVANCING EWD ACROSS NRN IL AND NRN IND ATTM. MODEL FORECASTS MOVE THIS FEATURE EWD ACROSS THE CNTRL APPALACHIAN MTNS TODAY INCREASING LARGE-SCALE ASCENT ACROSS VA AND NRN NC LATE THIS AFTERNOON. SFC DEWPOINTS NEAR 70 F IN THE APPALACHIAN FOOTHILLS AND COASTAL PLAINS SHOULD ALLOW MODERATE TO STRONG INSTABILITY TO DEVELOP BY MIDDAY. SCATTERED THUNDERSTORMS SHOULD INITIATE AND MOVE EWD ACROSS THE REGION DURING THE AFTERNOON AHEAD OF THE APPROACHING SHORTWAVE TROUGH. VERTICAL SHEAR PROFILES ARE FORECAST TO RANGE BETWEEN 20 AND 30 KT AND SHOULD BE STRONGEST IN VA AS THE UPPER-TROUGH APPROACHES. THIS COMBINED WITH THE STRONG INSTABILITY SHOULD BE SUFFICIENT FOR ISOLATED SEVERE THUNDERSTORMS. HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE STRONGER MULTICELL LINE SEGMENTS LATE THIS AFTERNOON INTO EARLY THIS EVENING. ...MID-MS VALLEY... A LARGE WARM SECTOR CURRENTLY EXISTS ACROSS THE MID MS VALLEY WHERE SFC DEWPOINTS ARE IN THE UPPER 60S AND LOWER 70S F. THE LOW-LEVEL MOISTURE SHOULD REMAIN IN PLACE TODAY ALLOWING STRONG INSTABILITY TO DEVELOP AS SFC TEMPS WARM. ALTHOUGH FORECAST SOUNDINGS ACROSS THE REGION SHOW RELATIVELY WEAK SHEAR PROFILES (0-6 KM SHEAR OF 10-20 KT)...THE STRONG INSTABILITY AND STEEP LOW-LEVEL LAPSE RATES SHOULD BE SUFFICIENT FOR A FEW MARGINALLY SEVERE STORMS. STRONG WIND GUSTS WILL BE MOST LIKELY WITH SHORT MULTICELL LINE SEGMENTS NEAR OR JUST AFTER PEAK HEATING. ..BROYLES/GRAMS.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 12:35:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 08:35:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131233 SWODY1 SPC AC 131231 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0731 AM CDT THU JUL 13 2006 VALID 131300Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF PLAINS STATES SWD TO OK... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF THE MID ATLANTIC STATES... ...SYNOPSIS... ENERGY WITH TROUGH NOW ENTERING THE NORTHERN HIGH PLAINS WILL SPLIT AS UPPER HIGH BUILDS NWD THRU INTERIOR WRN U.S. MAIN PORTION OF TROUGH CONTINUES EWD TO UPPER MS VALLEY BY LATE TONIGHT WITH A SRN PORTION HEADING SEWD DOWN THE MO RIVER VALLEY...REACHING MO BY 12Z FRI. A PERSISTENT SLY LOW LEVEL JET OF 20-30 KT CONTINUES TO FEED VERY MOIST AIR NWD THRU THE CENTRAL PLAINS IN ADVANCE OF THE COLD FRONT CURRENTLY LOCATED FROM CENTRAL ND SSWWD TO NEB PANHANDLE. BY MID-AFTERNOON THE COMBINATION OF STRONG HEATING WITH SFC TEMPERATURES TO NEAR 100F NWD INTO NEB AHEAD OF FRONT AND DEWPOINTS WELL INTO THE 60S WILL RESULT IN A VERY TO EXTREMELY UNSTABLE AIR MASS WITH MLCAPES POSSIBLY AOA 4000 J/KG. THE DIRECTIONAL SHEAR WITH LOW LEVEL SLYS AND 20-30KT NWLY MID LEVEL FLOW ACCOMPANYING THE S/WV TROUGH DROPPING SEWD THRU PLAINS...WILL PROVIDE 30-35KT OF DEEP LAYER SHEAR BY MID AFTERNOON. THIS IS MORE THAN SUFFICIENT TO SUPPORT SUPERCELL DEVELOPMENT GIVEN THE AVAILABLE INSTABILITY. BOTH THE NAM AND GFS HAVE A PARTICULARLY STRONG CONVECTIVE SIGNAL ON THE 06Z RUNS BY LATE THIS AFTERNOON OVER ERN NE AND THIS SEEMS REASONABLE GIVEN THE SYNOPTIC CONDITIONS. CAP WILL ERODE SUFFICIENTLY TO ALLOW RAPID INITIATION OF SURFACE BASED THUNDERSTORMS VICINITY FRONTAL ZONE BY LATE AFTERNOON. IN THE EARLY STAGES OF DEVELOPMENT VERY LARGE HAIL IS LIKELY WITH THE MODELS INDICATING RAPID DEVELOPMENT OF A COLD POOL GIVEN THE LARGE DCAPES UPWARDS TO 1500 J/KG OR GREATER IN THE WARM SECTOR. DAMAGING WINDS WILL THEN BE PRIMARY CONCERN AS A POTENTIAL SEVERE MCS PROPAGATES SEWD ACROSS ERN NEB INTO NRN KS AND NWRN MO. WILL RAISE PROBABILITIES OF BOTH WIND AND HAIL HOWEVER WITHHOLD A CATEGORY UPGRADE UNTIL NEXT MODEL RUN LENDS MORE CONFIDENCE IN THE INDICATED SCENARIO OF 06Z SOLUTIONS. SUFFICIENT INSTABILITY AND SHEAR AHEAD OF FRONT NWD TO THE CANADIAN BORDER FOR POTENTIAL SUPERCELLS AND DAMAGING WIND AND HAIL THREAT BY MID AFTERNOON. ...MID ATLANTIC STATES... E/W COLD FRONT ACROSS PA SLOWLY DROPPING SWD PRECEEDED BY A DEEP LAYER OF VERY MOIST AIR WITH PW/S IN EXCESS OF 2 INCHES. SEVERE THREAT IN THE E TODAY WILL MOST LIKELY OCCUR NEAR THE INTERFACE OF THE THICKER CLOUD COVER AND STRONG HEATING S OF FRONT OVER CENTRAL/SRN VA INTO NRN NC. WHILE MLCAPES IN THIS AREA WILL CLIMB TO 2000 J/KG OR MORE...THE WEAK LAPSE RATES AND MARGINAL SHEAR SHOULD CONFINE ANY SEVERE THREAT TO DAMAGING WINDS. THE 20-25KT OF SHEAR SUPPORT MULTICELL AND POSSIBLY LINE SEGMENTS DEVELOPING BY MID AFTERNOON WITH ASSOCIATED POTENTIAL WET MICRO BURSTS. ...MID MISSISSIPPI AND TN VALLEYS... VERY MOIST AND UNSTABLE AIR WILL PREVAIL S OF STATIONARY FRONTAL ZONE FROM THE MID MS VALLEY EWD TO APPALACHIANS. WEAK SHEAR PROFILES WILL BE CONDUCIVE TO PRIMARILY A PULSE SEVERE THREAT. THUS WHILE THERE IS THE POTENTIAL FOR DAMAGING DOWNBURSTS AND LARGE HAIL OVER MUCH OF THIS AREA...COVERAGE WILL BE LIMITED PRECLUDING TRYING TO IDENTIFY A RISK AREA ATTM. ..HALES/GRAMS.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 16:42:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 12:42:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 131640 SWODY1 SPC AC 131638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT THU JUL 13 2006 VALID 131630Z - 141200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF THE LWR MO VLY... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN DAKS/WRN MN SWD INTO OK AND MO... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE MID ATLANTIC STATES AND SOUTHEAST... ...SYNOPSIS... AN ACTIVE STORM PERIOD EXPECTED OVER THE CNTRL PLNS/LWR MO VLY AS WRN RIDGE REBOUNDS IN WAKE OF PROGRESSIVE SHORTWAVE TROUGH NOW ENTERING THE DAKOTAS. THE TROUGH LIKELY WILL SPLIT...WITH MAIN PORTION CONTINUING E TO THE UPR MS VALLEY BY LATE TONIGHT AS SRN PART DROPS SE ON NERN FRINGE OF RIDGE. ...CNTRL PLNS/LWR MO VLY... A VERY MOIST...VERY WARM BOUNDARY LAYER AIR MASS IS IN PLACE FROM THE CNTRL PLNS/LWR MO VLY NWD IN A NARROWING AXIS TO THE ERN DAKOTAS/WRN MN. STRONG HEATING WILL CONTINUE THROUGH THE AFTERNOON ALONG AND AHEAD OF WEAK COLD FRONT MOVING E/SE ACROSS THE DAKOTAS AND WRN NEB. SUBSTANTIAL HEATING WILL ALSO OCCUR ALONG STATIONARY FRONT EXTENDING ESE FROM ERN NEB INTO CNTRL/SRN IL. STEEPENING LOW LEVEL LAPSE RATES AND QUALITY MOISTURE SUPPLY SHOULD BOOST AFTERNOON SBCAPE TO AOA 4000 J/KG ACROSS A BROAD SWATH FROM CNTRL NEB ESE INTO PARTS OF KS/IA AND NRN MO. DEEP SHEAR ACROSS MDT AND SLGT RISK AREAS WILL INTENSIFY TODAY THROUGH TONIGHT AS MID LEVEL FLOW VEERS AND STRENGTHENS ON SW SIDE OF SHORTWAVE IMPULSE. BY MID TO LATE AFTERNOON...30-40 KT DEEP NWLY SHEAR SHOULD EXTEND FROM SE SD SEWD INTO NRN KS/NW MO. WITH TIME...STRONGER NW FLOW ALOFT SHOULD ALSO SPREAD S TOWARD THE SRN PLNS. OVERALL KINEMATIC/THERMODYNAMIC SETUP SUGGESTS THAT CONTINUED SURFACE HEATING WILL ALLOW SLIGHTLY ELEVATED STORMS NOW OVER NEB AND THE ERN DAKOTAS TO BECOME SURFACE-BASED A BIT LATER THIS AFTERNOON. OTHER STORMS LIKELY WILL FORM INVOF AFOREMENTIONED SURFACE BOUNDARIES NWD INTO THE ERN DAKOTAS. GIVEN DEGREE OF INSTABILITY AND STRENGTHENING SHEAR...CONDITIONS WILL BE FAVORABLE FOR SUSTAINED STORMS AND A FEW SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WET MICROBURSTS...ESPECIALLY IN NEB AND THE LWR MO VLY. THESE STORMS SHOULD FAIRLY QUICKLY MERGE INTO ONE OR TWO LARGE CLUSTERS...WITH FORWARD PROPAGATING SEGMENTS EXTENDING A THREAT FOR WIND/HAIL E/SE INTO PARTS OF KS/MO AND PERHAPS SRN IA BY EARLY THIS EVENING. ISOLATED HIGH WIND-PRODUCING STORMS MAY ALSO FORM INVOF LEE TROUGH IN NW KS...AND ALONG FRONT IN SRN IA. LATER TONIGHT AND EARLY FRIDAY...FORWARD-PROPAGATING CONVECTIVE SEGMENTS MAY EXTEND A THREAT FOR HIGH WIND SWD INTO NRN OK. ...MID ATLANTIC STATES... E/W COLD FRONT ACROSS PA WILL CONTINUE SLOWLY SWD...PRECEEDED BY A DEEP...WARM AND MOIST WLY FLOW INTO VA/NC. DIFFERENTIAL HEATING OCCURRING ALONG PREFRONTAL LINE OF CONVECTIVE DEBRIS...AND OROGRAPHIC INFLUENCE...LIKELY WILL INITIATE STORMS OVER SW VA/ERN TN AND NW NC A BIT LATER THIS AFTERNOON. MLCAPE WILL BE AOA 2000 J/KG...BUT RELATIVELY WEAK LAPSE RATES SHOULD LIMIT INTENSITY OF CONVECTIVE DEVELOPMENT. 20-25KT OF DEEP UNIDIRECTIONAL SHEAR SHOULD SUPPORT MULTICELL LINE SEGMENTS WITH THE POTENTIAL FOR SCATTERED WET MICROBURSTS. ...LWR TN VLY... VERY MOIST AND UNSTABLE AIR WILL PREVAIL S OF STATIONARY FRONTAL ZONE FROM THE MID MS VALLEY E TO APPALACHIANS. WEAK SHEAR WILL BE CONDUCIVE TO PRIMARILY A PULSE SEVERE THREAT. THUS WHILE THERE IS THE POTENTIAL FOR DAMAGING DOWNBURSTS AND LARGE HAIL OVER MUCH OF THIS AREA...COVERAGE SHOULD BE LIMITED. ..CORFIDI/GUYER.. 07/13/2006  From swody1 at goshenarc.org Thu Jul 13 20:19:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 16:19:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 132016 SWODY1 SPC AC 132015 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0315 PM CDT THU JUL 13 2006 VALID 132000Z - 141200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS SOUTHEASTERN NEBRASKA...NORTHEAST KANSAS...WESTERN IOWA...AND NORTHWEST MISSOURI.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A LARGE PORTION OF THE PLAINS STATES AND INTO THE MIDDLE AND UPPER MS VALLEY REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF VA/NC AND VICINITY... ...THE PLAINS INTO THE MID/UPPER MS VALLEY... VIGOROUS STORMS CONTINUE TO DEVELOP/ORGANIZE INVOF THE MID MO VALLEY...WHILE INCREASING STORM COVERAGE IS EVIDENT NWD INTO WRN MN AS WELL AS SEWD ACROSS ERN MO. AIRMASS HAS BECOME VERY UNSTABLE -- PARTICULARLY ACROSS THE MIDDLE MO VALLEY REGION...WHERE DEWPOINTS IN THE MID 70S BENEATH VERY STEEP LAPSE RATES ALOFT ARE RESULTING IN 2500 TO 4500 J/KG MEAN-LAYER CAPE. WITH 30 KT WNWLY FLOW ALOFT SPREADING EWD INTO THIS REGION BENEATH LOW-LEVEL SLYS...SHEAR REMAINS SUPPORTIVE OF ORGANIZED/SUPERCELL STORMS -- PARTICULARLY GIVEN DEGREE OF INSTABILITY. ALONG WITH POTENTIAL FOR WIDESPREAD/LARGE HAIL...DAMAGING WINDS ARE ALSO EXPECTED AS STORMS CONTINUE TO INCREASE IN COVERAGE AND INTENSITY. ATTM...IT APPEARS THAT MOST SIGNIFICANT SEVERE THREAT WILL EXIST ACROSS SERN NEB EWD INTO IA/NWRN MO AND SWD INTO NERN KS -- WHERE GREATEST COMBINATION OF SHEAR AND INSTABILITY ARE INDICATED. OVERNIGHT...EXPECT AXIS OF GREATEST THREAT TO SHIFT SWD AND EWD -- ACROSS ERN KS AND MO -- AS SWLY LOW-LEVEL JET DEVELOPS AIDING POTENTIAL FOR SEVERAL FORWARD-PROPAGATING MCS TO DEVELOP. ALONG WITH THREAT FOR HAIL...DAMAGING WINDS WILL REMAIN POSSIBLE AS STORMS SPREAD SEWD THROUGH THE END OF THE PERIOD. ...PARTS OF VA/NC AND VICINITY... THUNDERSTORMS CONTINUE TO DEVELOP INVOF SURFACE FRONT/AHEAD OF UPPER SHORT-WAVE TROUGH CROSSING WV/WRN VA ATTM...WITHIN MODERATELY-UNSTABLE AIRMASS. MODERATE/WLY FLOW WITH HEIGHT REMAINS IN PLACE OVER THIS REGION...BUT FLOW ROUGHLY PARALLEL TO THE SURFACE BOUNDARY WILL CONTINUE TO LIMIT SEVERE POTENTIAL. NONETHELESS...POTENTIAL FOR LOCALLY-DAMAGING WINDS WILL CONTINUE WITH STRONGER CELLS PRIOR TO THE ONSET OF DIURNAL BOUNDARY-LAYER STABILIZATION. ..GOSS.. 07/13/2006  From swody1 at goshenarc.org Fri Jul 14 00:57:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 13 Jul 2006 20:57:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140054 SWODY1 SPC AC 140052 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0752 PM CDT THU JUL 13 2006 VALID 140100Z - 141200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS PARTS OF THE CENTRAL PLAINS AND MID/UPPER MISSISSIPPI VALLEY.... ...THERE IS A SLGT RISK OF SVR TSTMS THIS EVE ACROSS PARTS OF THE SRN MID ATLANTIC COAST.... ...CENTRAL STATES... A SIGNIFICANT SHORT WAVE TROUGH...COMPRISED OF AT LEAST A COUPLE SMALLER SCALE IMPULSES...CONTINUES TO PROGRESS TO THE NORTHEAST OF A SOUTHWESTERN U.S. SUBTROPICAL HIGH CENTER. AS THIS MOTION CONTINUES TONIGHT...MODELS SUGGEST A RIDGE AXIS WILL BUILD TO THE NORTH OF THE HIGH...THROUGH THE CENTRAL ROCKIES/NORTHERN HIGH PLAINS. BULK OF DOWNSTREAM TROUGH WILL SHIFT INTO THE UPPER MISSISSIPPI VALLEY...BUT A SUBSTANTIAL MID-LEVEL JET STREAK/SHORT WAVE TROUGH IS PROGGED TO DIG SOUTH OF THE STRONGER WESTERLIES... THROUGH MUCH OF THE MID/LOWER MISSOURI VALLEY BY 12Z FRIDAY. MOST EXTENSIVE ONGOING CONVECTIVE DEVELOPMENT APPEARS TO BE IN ASSOCIATION WITH FORCING IN THE SOUTHERN PORTION OF THE SHORT WAVE TROUGH. THIS SEEMS LIKELY TO REMAIN THE CASE THROUGH THE NIGHT...SUPPORTED BY MOIST UNSTABLE AIR MASS WHICH IS PREVALENT THROUGH MUCH OF THE PLAINS/MISSISSIPPI AND OHIO VALLEYS. A CLUSTER OF STORMS WITH A SUBSTANTIAL COLD POOL NOW PROGRESSING INTO THE LOWER MISSOURI VALLEY WILL PROBABLY MAINTAIN A RISK OF DAMAGING WINDS/HAIL THROUGH MUCH OF THE EVENING. HOWEVER...TOWARD THE OVERNIGHT HOURS...AS IT APPROACHES THE ST. LOUIS AREA...AND PROGRESSES SOUTHEAST OF KANSAS CITY...COOLING OF BOUNDARY LAYER PROBABLY WILL BEGIN TO MITIGATE SEVERE THREAT. FARTHER WEST...NOCTURNAL STRENGTHENING OF SOUTHERLY LOW-LEVEL JET FROM CENTRAL OKLAHOMA THROUGH EASTERN KANSAS MAY SUPPORT ANOTHER EXPANDING CLUSTER OF STORMS THIS EVENING. MORE STRONGLY HEATED BOUNDARY LAYER ACROSS THE CENTRAL PLAINS WILL BE SLOWER TO COOL...MAINTAINING FAVORABLE ENVIRONMENT FOR SOUTHWARD PROPAGATING COLD POOL WITH DAMAGING WIND POTENTIAL...SOUTH OF INTERSTATE 70 TOWARD THE KANSAS/OKLAHOMA BORDER BY LATE EVENING...PERHAPS THE INTERSTATE 44 CORRIDOR BY THE END OF THE PERIOD. ...SOUTHERN MID ATLANTIC COAST... MAIN UPPER FORCING IS BEGINNING TO SHIFT OFFSHORE...BUT MIXED LAYER CAPE TO 2000 J/KG AHEAD OF SURFACE FRONT MAY MAINTAIN RELATIVELY VIGOROUS CONVECTIVE DEVELOPMENT ACROSS CENTRAL/NORTHEAST NORTH CAROLINA THIS EVENING. ISOLATED DAMAGING WIND GUSTS AND SOME HAIL WILL REMAIN POSSIBLE THROUGH AROUND 03-04Z...BEFORE ACTIVITY DIMINISHES FURTHER WITH CONTINUED BOUNDARY LAYER COOLING. ..KERR.. 07/14/2006  From swody1 at goshenarc.org Fri Jul 14 05:53:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 14 Jul 2006 01:53:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140551 SWODY1 SPC AC 140549 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1249 AM CDT FRI JUL 14 2006 VALID 141200Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN/EARLY EVE ACROSS PARTS OF THE UPPER GREAT LAKES/LOWER OHIO VALLEY.... SOUTHWESTERN STATES SUBTROPICAL RIDGE REMAINS STRONG...AND IS ALREADY BUILDING NORTHEASTWARD THROUGH THE CENTRAL ROCKIES AND PARTS OF THE NORTHERN HIGH PLAINS. FURTHER EXPANSION EASTWARD ACROSS THE CENTRAL/NORTHERN PLAINS THROUGH THE UPPER HALF OF THE MISSISSIPPI VALLEY IS PROGGED TO OCCUR TODAY...AS A SEASONABLY STRONG MID/UPPER JET...EMANATING FROM THE NORTHEAST PACIFIC... NOSES EASTWARD ALONG/JUST NORTH OF THE CANADIAN/U.S. BORDER. THIS IS EXPECTED TO SUPPORT THE EASTWARD PROGRESSION OF A WEAKENING UPPER TROUGH ACROSS THE GREAT LAKES/LOWER OHIO VALLEY REGION...TO THE SOUTH OF A SOMEWHAT STRONGER BELT OF WESTERLIES ACROSS EASTERN CANADA. ...MISSISSIPPI RIVER EASTWARD... DRYING IN THE WAKE OF UPPER TROUGH MIGRATING OFF THE NORTH ATLANTIC COAST SEEMS LIKELY TO LIMIT CONVECTIVE POTENTIAL ACROSS MUCH OF THE NORTHEAST DURING THIS FORECAST PERIOD. HOWEVER...MOST OTHER AREAS WILL REMAIN VERY MOIST...REFLECTED BY SURFACE DEW POINTS IN THE UPPER 60S/LOWER 70S. NORTH OF FLAT UPPER RIDGE ACROSS THE GULF STATES...CAPPING WILL BE WEAK...LIKELY ALLOWING WIDESPREAD CONVECTIVE DEVELOPMENT WITH DAYTIME HEATING. GUSTY WINDS AND MARGINALLY SEVERE HAIL WILL BE POSSIBLE IN STRONGER UPDRAFT PULSES WHERE CONVECTION FORMS. HOWEVER...SEVERE THREAT MAY BECOME MOST CONCENTRATED FROM PARTS OF THE UPPER MIDWEST INTO THE LOWER OHIO VALLEY. THIS IS WHERE MODELS SUGGEST STRONGEST DESTABILIZATION WILL OCCUR TODAY...WITH MIXED LAYER CAPE UP TO AROUND 3000 J/KG POSSIBLE BY PEAK HEATING...BENEATH REMNANT MID-LEVEL COLD POOL ASSOCIATED WITH WEAKENING UPPER TROUGH. POTENTIAL FOR A LARGE ORGANIZED CONVECTIVE CLUSTER SEEMS LOW...BUT NORTHWESTERLY MID/UPPER FLOW ON WESTERN/SOUTHERN PERIPHERY OF UPPER THERMAL TROUGH MAY CONTRIBUTE TO DEEP LAYER SHEAR AS STRONG AS 25-30KT. THIS WOULD ENHANCE RISK FOR LARGE HAIL IN SCATTERED STORMS ACROSS PARTS OF WISCONSIN/ILLINOIS INTO LOWER MICHIGAN/INDIANA DURING THE LATE AFTERNOON AND EARLY EVENING HOURS. ...SOUTHERN PLAINS INTO OZARK PLATEAU... CONVECTIVE OUTFLOW BOUNDARY FROM ONGOING CONVECTION IS EXPECTED TO STALL ACROSS PARTS OF NORTHERN ARKANSAS/OKLAHOMA EARLY TODAY. SOUTH OF THIS BOUNDARY...LOW-LEVEL THERMAL RIDGE AXIS IS EXPECTED TO BECOME A POSSIBLE FOCUS FOR SCATTERED NEW AFTERNOON THUNDERSTORMS...MOSTLY IN RESPONSE TO STRONG SURFACE HEATING. LATENT INSTABILITY MAY NOT BECOME PARTICULARLY LARGE DUE TO WARM MID-LEVEL ENVIRONMENT...BUT HOT DEEP MIXED BOUNDARY LAYER WITH 30-40 DEGREE TEMPERATURE/DEW POINT SPREADS WILL BE FAVORABLE FOR LOCALIZED DOWNBURSTS. ..KERR.. 07/14/2006  From swody1 at goshenarc.org Fri Jul 14 12:25:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 14 Jul 2006 08:25:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141223 SWODY1 SPC AC 141222 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0722 AM CDT FRI JUL 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS IN THE GREAT LAKES STATES.... ...SYNOPSIS... SHORTWAVE TROUGH...CURRENTLY MOVING INTO WRN WI/NWRN IL...IS FORECAST TO MOVE ESEWD THROUGH THE DAY AND EXTEND FROM SRN LOWER MI SWWD INTO INDIANA BY LATE AFTERNOON. RIDGE OVER THE SWRN STATES WILL BUILD NWD IN THE WAKE OF THE EXITING UPPER TROUGH. A WEAK SURFACE WAVE...ASSOCIATED WITH THE UPPER TROUGH...IS EXPECTED TO BE LOCATED OVER LOWER MI...WITH A WEAK TRAILING BOUNDARY EXTENDING SWWD INTO SRN MO. ...GREAT LAKE STATES... CONVECTION MOVING THROUGH WI THIS MORNING WILL SHIFT EWD THROUGH THE DAY AND MAY GRADUALLY INTENSIFY AS IT ENCOUNTERS AN INCREASINGLY WARMING AND UNSTABLE AIR MASS ACROSS SRN LOWER MI. STORMS ARE ALSO LIKELY TO REDEVELOP WITHIN FORCING LOCATED AHEAD OF UPPER TROUGH AND AN MCV MOVING EWD OUT OF CENTRAL MO INTO IL AND INDIANA DURING THE AFTERNOON HOURS. SURFACE DEW POINTS IN THE UPPER 60S/LOWER 70S SHOULD RESULT IN MLCAPES FROM 2000 TO 3000 J/KG ACROSS THIS REGION BY MID/LATE AFTERNOON. ALTHOUGH MID LEVEL WINDS ARE FORECAST TO INCREASE TO 30 KT...MOSTLY UNIDIRECTIONAL WINDS ABOVE THE BOUNDARY LAYER SHOULD RESULT IN DEEP LAYER SHEAR OF ONLY 20-25KT. HOWEVER...THIS SHEAR AND THE DEGREE OF INSTABILITY WOULD SUPPORT SEVERE MULTICELL STORMS WITH SEVERE WIND/HAIL EVENTS. STORMS SHOULD WEAKEN/DISSIPATE AFTER SUNSET AS THE BOUNDARY LAYER STABILIZES. ...SOUTHERN PLAINS INTO OZARK PLATEAU... OUTFLOW BOUNDARY WITH SLOWLY WEAKENING CONVECTION EXTENDED FROM CENTRAL AR WWD INTO CENTRAL/NWRN OK. A RELATIVELY STRONG MESO-HIGH ASSOCIATED WAS PUSHING THIS BOUNDARY SWD...AND SHOULD EXTEND FROM SRN AR WWD INTO NERN TX...AND THEN NWWD INTO SWRN OK/TX PANHANDLE BEFORE STALLING LATER THIS MORNING. WEAK CONVERGENCE ALONG THIS BOUNDARY MAY PROVIDE SUFFICIENT LIFT FOR RENEWED CONVECTIVE DEVELOPMENT LATE THIS AFTERNOON. ALTHOUGH INSTABILITY WILL NOT BE PARTICULARLY STRONG...DUE TO WARM MID-LEVEL TEMPERATURES...DEEP MIXED BOUNDARY LAYER...WITH 30-40 DEGREE SURFACE TEMPERATURE/DEW POINT SPREADS...MAY SUPPORT A LOCALIZED THREAT FOR SHORT LIVED MICRO BURSTS. ...TN/UPPER OH VALLEYS EWD INTO THE CAROLINAS... STRONG HEATING OF THE MOIST BOUNDARY LAYER WILL RESULT IN MLCAPE VALUES TO RANGE FROM 2000 TO 3000 J/KG. DESPITE THE LACK OF DYNAMICAL FORCING...A WEAK CAP SHOULD ALLOW SCATTERED THUNDERSTORM CLUSTERS TO DEVELOP. WEAK WINDS/SHEAR WILL RESULT IN DISORGANIZED STORMS...BUT STRONG TEMPERATURE DIFFERENTIAL BETWEEN THE HEAVY RAIN CORES AND HOT ENVIRONMENTAL CONDITIONS MAY RESULT IN ISOLATED SHORT LIVED MICROBURSTS. ..IMY.. 07/14/2006  From swody1 at goshenarc.org Mon Jul 17 00:57:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 16 Jul 2006 20:57:58 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170055 SWODY1 SPC AC 170053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT SUN JUL 16 2006 VALID 170100Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF ERN SD EWD TO THE UPPER GRTLKS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE DESERT SW... ...ERN SD EWD TO THE UPPER GRTLKS... LATEST SFC MESOANALYSIS PLACES A WEAK TROUGH FROM NEAR LAKE OF THE WOODS SWWD INTO CNTRL SD...ASSOCIATED WITH A SUBTROPICAL IMPULSE MIGRATING EWD THROUGH SD. A STRONGER NRN STREAM IMPULSE WAS DIGGING SEWD THROUGH THE CANADIAN PRAIRIES WITH A MORE SIGNIFICANT COLD FRONT ARCING FROM LAKE WINNIPEG SWWD INTO NCNTRL MT. HIGH-BASED TSTMS ROOTED INTO THE VERY UNSTABLE BOUNDARY LAYER ACROSS THE MN ARROWHEAD EARLY THIS EVE...PRESUMABLY WHERE LOW-LEVEL WARM ADVECTION WAS MAXIMIZED JUST NE OF THE PRIMARY THERMAL RIDGE OVER THE PLAINS. THESE TSTMS HAVE WEAKENED...BUT NEW STORMS MAY FORM OVERNIGHT...BOTH ALONG THE LLJ AXIS FROM LK SUP EWD INTO UPPER MI...NWRN-SRN ONT...AND AHEAD OF THE NRN STREAM JETLET ACROSS NRN MN. SUFFICIENT EFFECTIVE SHEAR WILL EXIST FOR SUPERCELLS...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE. A SECONDARY AREA OF TSTM DEVELOPMENT APPEARS PROBABLE ACROSS EXTREME ERN SD EWD INTO CNTRL/SRN MN THIS EVE AHEAD OF THE SUBTROPICAL DISTURBANCE. THESE STORMS...INITIALLY HIGH-BASED...COULD TAP INTO MORE UNSTABLE PARCELS EMANATING FROM THE HIGHER THETA-E AXIS ACROSS THE CORN BELT. IF THIS OCCURS...WHETHER STORMS REMAIN ELEVATED OR BECOME SFC BASED...LARGE HAIL AND/OR DAMAGING WINDS WILL BE RISKS. THESE STORMS COULD MOVE INTO PARTS OF THE UPPER MS VLY REGION BY 12Z MON. ...DESERT SW... ENHANCED LOW/MID-TROPOSPHERIC ELY FLOW DOMINATED THE DIURNAL CYCLE AGAIN OVER SERN AZ...CONTRIBUTING TO DOWNSLOPE AND SUBSEQUENT DRYING OF THE BOUNDARY LAYER...LIMITING INSTABILITY. FARTHER NW...TSTMS HAVE BEEN WIDELY SCATTERED AND FAVORING AREAS THAT DID NOT SEE ROBUST CONVECTION YESTERDAY. MOST UNSTABLE AIR MASS THIS EVENING REMAINS OVER THE LOWER DESERTS FROM WRN PIMA COUNTY NWD TO MOHAVE COUNTY. TSTMS THAT DEVELOP/MOVE WITHIN/INTO THIS INSTABILITY AXIS WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS/HAIL. BUT...OVERALL...THE SEVERE THREATS SEEM TO BE LOWER THAN PREVIOUSLY ANTICIPATED. ..RACY.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 05:56:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 01:56:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170553 SWODY1 SPC AC 170551 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1251 AM CDT MON JUL 17 2006 VALID 171200Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... ...SYNOPSIS... UPPER RIDGE AXIS IS EXPECTED TO REMAIN STRONG ACROSS THE MAJORITY OF THE COUNTRY ON MON. A TWO STREAM FLOW WILL EXIST ALONG THE NRN PERIPHERY OF THE RIDGE WITH THE STRONGEST NRN STREAM SKIRTING THE GRTLKS AND NRN NEW ENGLAND REGIONS...WITH A WEAKER SUBTROPICAL STREAM ARCING FROM THE NRN ROCKIES TO THE MIDWEST. A COUPLE OF SHORTWAVE TROUGHS WILL BE THE IMPETUS FOR POSSIBLE SEVERE TSTMS MON AFTN/NIGHT. NRN STREAM IMPULSE...NOW OVER SRN MANITOBA...WILL DIG SEWD THROUGH THE GRTLKS REGION BY MON AFTN...THEN APPROACH NRN NEW ENGLAND BY 12Z TUE. MEANWHILE...A SUBTROPICAL WAVE OVER THE UPPER MS VLY AT THE START OF THE PERIOD WILL MOVE ESEWD INTO THE CORN BELT MON AFTN...THEN THE MIDWEST BY EARLY TUE. ...UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... HIGH-BASED TSTMS NOW DEVELOPING ACROSS PORTIONS OF ERN SD AND MN ARE LIKELY TO SPREAD EWD INTO THE UPPER MS VLY BY 12Z...AND SHOULD WEAKEN MON MORNING AS THE LLJ RELAXES. THE PRIMARY SEVERE THREAT WILL DEVELOP MON AFTN/EVE. PLUME OF HOT TEMPERATURES WILL BE MAINTAINED ALONG/AHEAD OF THE SEWD MOVING COLD FRONT ASSOCIATED WITH THE NRN STREAM IMPULSE. GIVEN BOUNDARY LAYER DEW POINTS BEING MAINTAINED AOA 65 DEG F...MLCAPES WILL RANGE FROM 2000-4000 J PER KG. AS STRONGER MID-LEVEL HEIGHT FALLS/COOLING SPREAD SEWD ACROSS LAKE SUPERIOR...TSTM WILL INITIATE ALONG THE COLD FRONT FROM UPPER MI AND BACKBUILD SWWD INTO PARTS OF WI BY MID-AFTN MON. VERTICAL SHEAR WILL BE SUFFICIENT FOR SUPERCELLS...BUT EVOLUTION INTO LINE SEGMENTS WILL BE FAVORED. GIVEN UNIDIRECTIONAL WLY FLOW...BOW ECHOES ARE POSSIBLE WITH DAMAGING WINDS AND LARGE HAIL. THIS ACTIVITY WILL MOVE ESEWD INTO SRN ONT AND PARTS OF LWR MI DURING MON EVE AND PROBABLY WEAKEN OVERNIGHT AS THE PRIMARY UPPER FORCING MOVES EWD INTO CANADA. MEANWHILE...A SEPARATE CLUSTER OF TSTMS IS LIKELY TO FORM ACROSS PARTS OF IA MON AFTN. CINH WILL BE GREATER THAN FARTHER NE...BUT VERY HOT TEMPERATURES AND PRESENCE OF A SUB-TROPICAL DISTURBANCE MOVING THROUGH THE REGION SHOULD BE FAVORABLE FOR SCT TSTMS. GIVEN MAGNITUDE OF LAPSE RATES/INSTABILITY...STORMS WILL GROW RAPIDLY AND SUPERCELLS WILL BE POSSIBLE WITH LARGE HAIL. ACTIVITY COULD EVOLVE INTO AN MCS DURING THE EVENING...AND ACCELERATE EWD INTO SRN WI AND NRN IL OVERNIGHT WITH A DAMAGING WIND THREAT. ...SWRN DESERTS... UPPER LEVEL LOW WILL CONTINUE TO ROTATE WWD THROUGH SONORA/SRN AZ INTO SRN CA MON INTO TUE. ENHANCED ELY FLOW ALONG NRN PERIPHERY OF THIS FEATURE WILL CONTINUE ACROSS THE SWRN DESERTS. TSTMS WILL LIKELY FORM OVER THE RIM AND ACROSS THE LWR DESERTS TOWARD THE LWR CO RVR VLY MON AFTN/EVE. ISOLD DAMAGING WINDS WILL BE POSSIBLE. SERN AZ MAY AGAIN SEE AFTN DRYING OF THE BOUNDARY LAYER IF THE LOW-LEVEL AMBIENT FLOW REGIME OVERCOMES THE DIURNAL CYCLE. THIS WOULD TEND TO REDUCE THE OVERALL CONVECTIVE/SEVERE THREATS OVER THAT AREA. ...GULF COASTAL REGION... WEAK E-W ORIENTED UPPER SHEAR AXIS WILL REMAIN ALONG THE GULF COASTAL REGION ON MON. GIVEN A WEAK LOW-LEVEL CONVERGENCE ZONE...PRESENCE OF VERY HIGH PRECIPITABLE WATER VALUES AND HOT CONDITIONS...TSTM WILL BE LIKELY FROM PARTS OF ERN TX EWD TO NRN FL. WEAK TROPOSPHERIC FLOW WILL FAVOR MULTICELL STORM CLUSTERS THAT WILL LIKELY PULSE TO NEAR SEVERE LEVELS WITH DAMAGING WINDS THE PRIMARY SEVERE RISK. ACTIVITY WILL BE LARGELY TIED TO THE DIURNAL CYCLE AND WEAKEN DURING THE MID-EVENING. ..RACY/JEWELL.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 12:45:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 08:45:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 171243 SWODY1 SPC AC 171241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT MON JUL 17 2006 VALID 171300Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL GREAT LAKES SWWD INTO NRN IL AND ERN IA.... ...SYNOPSIS... UPPER RIDGE AXIS WILL REMAIN ANCHORED E-W ACROSS MOST OF THE CONUS ...THOUGH A STRONG SHORTWAVE TROUGH WILL MOVE ESEWD THROUGH SRN ONTARIO AND LOWER HEIGHTS ACROSS THE GREAT LAKES REGION DURING THE PERIOD. AN ASSOCIATED COLD FRONT...CURRENTLY MOVING THROUGH THE WRN GREAT LAKES...IS FORECAST TO EXTEND FROM NRN LOWER MI SWWD INTO SOUTH CENTRAL IA/NORTH CENTRAL KS BY LATE AFTERNOON. ...CENTRAL UPPER MS VLY NEWD INTO THE CNTRL GRTLKS REGION... STRONG CAPPING INVERSION WILL ONCE AGAIN PLAY HAVOC WITH TIMING AND LOCATION OF SEVERE STORMS TODAY...THOUGH COOLING ALOFT AND LARGE SCALE ASCENT SHOULD WEAKEN THE INVERSION ENOUGH FOR SURFACE BASED STORMS TO DEVELOP ALONG THE FRONT THIS AFTERNOON. THIS MORNING...MOSTLY NON-SEVERE ELEVATED CONVECTION IS EXPECTED ACROSS SERN MN/NWRN IA/U.P./WI...AHEAD OF A WEAK SUBTROPICAL SHORTWAVE TROUGH LOCATED IN CENTRAL MN. THERE IS A SMALL CHANCE THAT STORMS EAST OF LAKE SUPERIOR COULD BACKBUILD INTO THE ERN U.P. THIS MORNING AS THE CAP SLOWLY WEAKENS. INTENSE SURFACE BASED STORMS ARE MOST LIKELY TO DEVELOP MID/LATE AFTERNOON FROM NRN/CENTRAL LOWER MI SWWD INTO SRN WI...AND EVENTUALLY ERN IA AS THE STORMS BACKBUILD SWWD ALONG THE FRONT. ONCE SURFACE BASED STORMS DEVELOP...THEY WILL BE LOCATED WITHIN A VERY UNSTABLE AIRMASS WITH MLCAPES FROM 3000 TO 4000 J/KG. THE DEGREE OF INSTABILITY COMBINED WITH 40 KT DEEP LAYER SHEAR WILL BE FAVORABLE FOR SUPERCELLS. THE AMOUNT OF INSTABILITY SHOULD SUPPORT VERY LARGE HAIL...ESPECIALLY THE FIRST FEW HOURS AFTER INITIATION SINCE THE STORMS ARE EXPECTED TO BE CELLULAR. THEREAFTER...THE OUTFLOWS SHOULD MERGE INTO A SEWD MOVING LINE ALONG THE FRONT... WITH WIND DAMAGE BECOMING THE MAIN SEVERE THREAT AS THE STORMS MOVE INTO SRN LOWER MI AND NRN IL DURING THE EVENING. HOWEVER... THE LOW LEVEL JET AND MASS CONVERGENCE ARE FORECAST TO WEAKEN OVERNIGHT...SO THE STORMS SHOULD WEAKEN AS THEY MOVE SEWD INTO NRN INDIANA/CENTRAL IL OVERNIGHT. ...SWRN DESERTS... WEAK UPPER LEVEL CIRCULATION SHOULD CONTINUE MOVING SLOWLY WWD INTO SRN CA TODAY. THE MOIST AND UNSTABLE ENVIRONMENT PLUS THE LIFT ASSOCIATED WITH THE UPPER LOW SHOULD ONCE AGAIN INITIATE AFTERNOON THUNDERSTORMS OVER THE RIM. WITH 35 KT ELY MID LEVEL WINDS...THESE STORMS SHOULD MOVE WWD INTO THE LWR DESERTS TOWARD THE LOWER CO RIVER VALLEY DURING THE LATE AFTERNOON/EVENING HOURS. ALTHOUGH ISOLATED WIND DAMAGE IS POSSIBLE...THE WIND THREAT MAY BE LOWER THAN THE PAST FEW DAYS DUE TO THE STRONG CONVECTIVE OVERTURNING. ...GULF COASTAL REGION... A DIFFUSE SURFACE TROUGH AND WEAK CAPPING SHOULD RESULT IN SCATTERED THUNDERSTORMS TO DEVELOP DURING THE AFTERNOON...ROUGHLY WITHIN 100 NM OF THE GULF COAST FROM SERN TX TO THE FL PANHANDLE. A HOT AND MOIST BOUNDARY LAYER WILL FAVOR MULTICELL CLUSTERS WITH A POTENTIAL FOR BRIEF STRONG DOWNBURSTS. THE STORMS SHOULD DIE OUT QUICKLY AFTER 01Z WITH LOSS OF DAYTIME HEATING. ..IMY/JEWELL.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 16:31:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 12:31:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 171629 SWODY1 SPC AC 171627 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1127 AM CDT MON JUL 17 2006 VALID 171630Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO EARLY TONIGHT FROM ERN IA TO MI.... ...MS VALLEY/GREAT LAKES AREA THIS AFTERNOON INTO TONIGHT... A MID LEVEL SHORTWAVE TROUGH OVER ONTARIO...WITH A LOBE EXTENDING SWD OVER MN/WI...WILL MOVE GENERALLY EWD OVER THE GREAT LAKES THROUGH EARLY TUESDAY. AN ASSOCIATED SURFACE COLD FRONT WILL CONTINUE SEWD ACROSS IA/WI/NRN IL/MI BY LATE TONIGHT. THIS SURFACE FRONT WILL PROVIDE A FOCUS FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON INTO TONIGHT ACROSS THE SLIGHT RISK AREA. SURFACE ANALYSES AND 12Z SOUNDINGS SHOW LOWER 70S BOUNDARY LAYER DEWPOINTS BENEATH A PLUME OF 8-9 C/KM MID LEVEL LAPSE RATES WITHIN THE WARM SECTOR. WHEN COMBINED WITH AFTERNOON TEMPERATURES IN THE 90S...STRONG INSTABILITY /MLCAPE VALUES FROM 3000-4000 J/KG/ WILL BE PRESENT FROM ERN IA NEWD INTO LOWER MI BY MID-LATE AFTERNOON. THE ELEVATED MIXED LAYER SHOULD CONFINE THUNDERSTORM DEVELOPMENT TO THE IMMEDIATE FRONTAL ZONE BY 21-00Z WHERE DEEP MIXING/ASCENT WILL REMOVE CONVECTIVE INHIBITION. THE STRONG INSTABILITY AND MODEST DEEP LAYER VERTICAL SHEAR MAY SUPPORT A FEW SUPERCELLS AND/OR BOWING SEGMENTS WITHIN A THE BAND OF STORMS ALONG THE FRONT. LARGE HAIL...SOME OF WHICH COULD BE QUITE LARGE GIVEN THE VERY STEEP MID LEVEL LAPSE RATES...AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE THREATS THIS AFTERNOON INTO EARLY TONIGHT. ...CENTRAL/SRN AZ...SE CA...EXTREME SRN NV THIS AFTERNOON/EVENING... A PRONOUNCED WAVE IN THE ELYS IS NOW MOVING OVER NRN BAJA. RELATIVELY RICH LOW-MID LEVEL MOISTURE HAS OVERSPREAD MUCH OF CENTRAL/SRN AZ AND SE CA IN ASSOCIATION WITH THIS WAVE...AND SEVERAL CLUSTERS OF THUNDERSTORMS WILL LIKELY FORM AGAIN TODAY OVER RIM IN AZ AND OTHER MORE LOCALIZED TERRAIN FEATURES. AFTERNOON MLCAPE VALUES OF 1000-1500 J/KG AND 25-30 KT ELY/ESELY MID LEVEL FLOW SHOULD SUPPORT A FEW ORGANIZED MULTICELL CLUSTERS THAT WILL MOVE WWD OFF THE HIGHER TERRAIN THIS AFTERNOON/EVENING. THE STRONGEST STORMS COULD PRODUCE ISOLATED DAMAGING OUTFLOW WINDS AND MARGINALLY SEVERE HAIL. ...GULF COAST THIS AFTERNOON... A REMNANT MID LEVEL CYCLONIC CIRCULATION HAS DRIFTED SSWWD OVER SRN MS/SE LA...AND A WEAK NW-SE ORIENTED SURFACE TROUGH/FRONT PERSISTS FROM NRN LA INTO SRN MS/AL. MODIFIED MORNING SOUNDINGS SHOW THE POTENTIAL FOR STRONG INSTABILITY THIS AFTERNOON AND MINIMAL CONVECTIVE INHIBITION WITH SURFACE TEMPERATURES IN THE LOWER 90S. THE STRONGEST STORMS MAY PRODUCE ISOLATED DAMAGING DOWNBURST WINDS GIVEN THE STRONG INSTABILITY...SOME DRY AIR ALOFT...AND STEEP LOW-LEVEL LAPSE RATES THIS AFTERNOON. ..THOMPSON/CROSBIE.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 20:05:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 16:05:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 172002 SWODY1 SPC AC 172000 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0300 PM CDT MON JUL 17 2006 VALID 172000Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES INTO THE MIDDLE MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN TX INTO WRN/SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF CENTRAL/SRN AZ... ...GREAT LAKES/MIDDLE MS VALLEY... WATER VAPOR IMAGERY SHOWS A STRONG SHORT WAVE TROUGH MOVING EWD ACROSS ONTARIO/LAKE SUPERIOR...ACCOMPANIED BY A 50-60 KT MID LEVEL JET STREAK OVER LAKE SUPERIOR AND NRN WI/UPR MI. SURFACE COLD FRONT IS CURRENTLY EXTENDING FROM ERN LAKE SUPERIOR ACROSS CENTRAL WI INTO SWRN IA...AND THIS BOUNDARY IS EXPECTED TO REACH A ST LAWRENCE VALLEY/CENTRAL INDIANA/CENTRAL MO LINE BY 18/12Z. VERY MOIST AND WARM AIR MASS IS LOCATED AHEAD OF THE FRONT WITH SURFACE TEMPERATURES IN THE 90S AND DEW POINTS IN THE 70S. 12Z SOUNDINGS INDICATED ELEVATED MIXED LAYER/STEEP MID LEVEL LAPSE RATES EXTENDED EWD INTO THE GREAT LAKES REGION...ENHANCING POTENTIAL INSTABILITY /MLCAPE OF 3000-4000 J/KG/ BUT ALSO LIMITING CONVECTIVE DEVELOPMENT IN THE WARM SECTOR AHEAD OF THE COLD FRONT. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS HAVE FORMED FROM NRN LOWER MI SWWD INTO EAST CENTRAL WI AND NERN IA...AND A WEAKENING CAP IMMEDIATELY ALONG/AHEAD OF THE FRONT SHOULD PERMIT ADDITIONAL STORMS TO DEVELOP THIS AFTERNOON AND EVENING. PRESENCE OF VERY UNSTABLE ENVIRONMENT COUPLED WITH 30-40 KT DEEP LAYER VERTICAL SHEAR WILL SUPPORT ADDITIONAL SEVERE STORMS TO DEVELOP THROUGH THE EVENING HOURS...WITH STRONGEST UPDRAFTS CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS. STRONG/SEVERE CONVECTION MOVING FROM WI INTO LOWER MI AND TOWARD THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS AS STRONG DYNAMIC FORCING ASSOCIATED WITH THE SHORT WAVE OVERSPREADS THE AREA FROM THE WEST AND PROVIDES FAVORABLE FORCING FOR LARGE SCALE ASCENT. A FEW SEVERE STORMS MAY ALSO DEVELOP SWWD ALONG THE FRONT INTO PARTS OF CENTRAL/SWRN IA LATER THIS AFTERNOON WHERE VISIBLE IMAGERY SHOWS CU FIELD BECOMING ENHANCED...WITH THIS ACTIVITY GRADUALLY SPREADING SEWD INTO NRN MO. THIS ACTIVITY IS LIKELY TO WEAKEN AFTER SUNSET. ...ARKLATEX INTO SRN LA... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL CYCLONIC CIRCULATION MOVING SLOWLY SWD ACROSS SERN LA...WITH STRONG MID/UPPER LEVEL DRYING SPREADING SWD ACROSS THE REGION. THERMODYNAMIC PROFILES ARE CHARACTERIZED BY INCREASING TEMPERATURE/DEW POINT SPREADS AS A LOW LEVEL INVERTED-V SOUNDING STRUCTURE DEVELOPS IN THE LOWEST 1-2 KM...WITH THETA-E DECREASING RAPIDLY ABOVE THE VERY MOIST PBL. 20 KT NELY WINDS ALOFT WILL FAVOR SWWD PROPAGATION OF STORMS WITH POTENTIAL FOR WET MICROBURSTS TO DEVELOP. SEE MESOSCALE DISCUSSION 1537 FOR MORE DETAILS. ...CENTRAL/SRN AZ... VISIBLE IMAGERY SHOWS REMNANTS OF A MESOSCALE CONVECTIVE VORTEX MOVING NWWD OVER SERN AZ. ENVIRONMENT IN ADVANCE OF THIS FEATURE IS MODERATELY MOIST WITH SURFACE DEW POINTS IN THE UPPER 50S/LOWER 60S...AND STRONG INSOLATION SHOULD ALLOW TEMPERATURES TO CONTINUE WARMING THIS AFTERNOON. CONVECTION IS EXPECTED TO GRADUALLY INCREASE OVER THE HIGHER TERRAIN OF SERN AZ...WITH STORMS SPREADING NWWD INTO THE LOWER DESERTS OF SOUTH CENTRAL AND SWRN AZ WITHIN BAND OF 20-25 KT ESELY FLOW IN THE 700-500 MB LAYER. STEEP LOW LEVEL LAPSE RATES WITHIN WELL-MIXED BOUNDARY LAYER EXTENDING UP TO 750-700 MB AND ASSOCIATED LARGE VALUES OF DOWNDRAFT CAPE INDICATE POTENTIAL FOR WET MICROBURSTS PRODUCING DAMAGING WIND GUSTS AND REDUCED VISIBILITIES IN BLOWING DUST. ..WEISS.. 07/17/2006  From swody1 at goshenarc.org Mon Jul 17 23:24:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 19:24:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 172322 SWODY1 SPC AC 172320 DAY 1 CONVECTIVE OUTLOOK AMEND 1 NWS STORM PREDICTION CENTER NORMAN OK 0620 PM CDT MON JUL 17 2006 VALID 172000Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE GREAT LAKES INTO THE MIDDLE MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN TX INTO WRN/SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SWRN DESERTS/LWR CO RVR VLY... AMENDED FOR SLGT RISK ACROSS THE LAS VEGAS AREA ***AMENDED PORTION*** ...LWR CO RVR VLY AND THE SWRN DESERTS... STRONGEST TSTMS HAVE DEVELOPED ALONG THE HIGH COUNTRY ACROSS NWRN AZ NWD INTO AREAS N-E OF KLAS. THESE STORMS WILL PROPAGATE WWD TOWARD THE LWR CO RVR VLY AREA...INCLUDING THE LAS VEGAS VLY LATER THIS EVENING WITH RISKS OF DAMAGING WINDS AND PERHAPS HAIL. FARTHER S...ACTIVITY HAS BEEN SUPPRESSED THIS AFTN. BUT...AN MCV CONTINUES TO MOVE WNWWD THROUGH PIMA COUNTY AND MAY BE THE IMPETUS FOR INCREASING TSTMS LATER THIS EVENING. THESE STORMS WILL ALSO HAVE A RISK OF DAMAGING WINDS. ***REMAINDER UNCHANGED*** ...GREAT LAKES/MIDDLE MS VALLEY... WATER VAPOR IMAGERY SHOWS A STRONG SHORT WAVE TROUGH MOVING EWD ACROSS ONTARIO/LAKE SUPERIOR...ACCOMPANIED BY A 50-60 KT MID LEVEL JET STREAK OVER LAKE SUPERIOR AND NRN WI/UPR MI. SURFACE COLD FRONT IS CURRENTLY EXTENDING FROM ERN LAKE SUPERIOR ACROSS CENTRAL WI INTO SWRN IA...AND THIS BOUNDARY IS EXPECTED TO REACH A ST LAWRENCE VALLEY/CENTRAL INDIANA/CENTRAL MO LINE BY 18/12Z. VERY MOIST AND WARM AIR MASS IS LOCATED AHEAD OF THE FRONT WITH SURFACE TEMPERATURES IN THE 90S AND DEW POINTS IN THE 70S. 12Z SOUNDINGS INDICATED ELEVATED MIXED LAYER/STEEP MID LEVEL LAPSE RATES EXTENDED EWD INTO THE GREAT LAKES REGION...ENHANCING POTENTIAL INSTABILITY /MLCAPE OF 3000-4000 J/KG/ BUT ALSO LIMITING CONVECTIVE DEVELOPMENT IN THE WARM SECTOR AHEAD OF THE COLD FRONT. SEVERAL CLUSTERS OF STRONG/SEVERE THUNDERSTORMS HAVE FORMED FROM NRN LOWER MI SWWD INTO EAST CENTRAL WI AND NERN IA...AND A WEAKENING CAP IMMEDIATELY ALONG/AHEAD OF THE FRONT SHOULD PERMIT ADDITIONAL STORMS TO DEVELOP THIS AFTERNOON AND EVENING. PRESENCE OF VERY UNSTABLE ENVIRONMENT COUPLED WITH 30-40 KT DEEP LAYER VERTICAL SHEAR WILL SUPPORT ADDITIONAL SEVERE STORMS TO DEVELOP THROUGH THE EVENING HOURS...WITH STRONGEST UPDRAFTS CAPABLE OF PRODUCING VERY LARGE HAIL AND DAMAGING WIND GUSTS. STRONG/SEVERE CONVECTION MOVING FROM WI INTO LOWER MI AND TOWARD THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS AS STRONG DYNAMIC FORCING ASSOCIATED WITH THE SHORT WAVE OVERSPREADS THE AREA FROM THE WEST AND PROVIDES FAVORABLE FORCING FOR LARGE SCALE ASCENT. A FEW SEVERE STORMS MAY ALSO DEVELOP SWWD ALONG THE FRONT INTO PARTS OF CENTRAL/SWRN IA LATER THIS AFTERNOON WHERE VISIBLE IMAGERY SHOWS CU FIELD BECOMING ENHANCED...WITH THIS ACTIVITY GRADUALLY SPREADING SEWD INTO NRN MO. THIS ACTIVITY IS LIKELY TO WEAKEN AFTER SUNSET. ...ARKLATEX INTO SRN LA... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL CYCLONIC CIRCULATION MOVING SLOWLY SWD ACROSS SERN LA...WITH STRONG MID/UPPER LEVEL DRYING SPREADING SWD ACROSS THE REGION. THERMODYNAMIC PROFILES ARE CHARACTERIZED BY INCREASING TEMPERATURE/DEW POINT SPREADS AS A LOW LEVEL INVERTED-V SOUNDING STRUCTURE DEVELOPS IN THE LOWEST 1-2 KM...WITH THETA-E DECREASING RAPIDLY ABOVE THE VERY MOIST PBL. 20 KT NELY WINDS ALOFT WILL FAVOR SWWD PROPAGATION OF STORMS WITH POTENTIAL FOR WET MICROBURSTS TO DEVELOP. SEE MESOSCALE DISCUSSION 1537 FOR MORE DETAILS. ..JPR/WEISS.. 07/17/2006  From swody1 at goshenarc.org Tue Jul 18 00:53:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 17 Jul 2006 20:53:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 180050 SWODY1 SPC AC 180048 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0748 PM CDT MON JUL 17 2006 VALID 180100Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MIDWEST TO THE CNTRL GRTLKS... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SWRN DESERTS... ...MIDWEST TO THE CNTRL GRTLKS... PRIMARY UPPER SHORTWAVE TROUGH HAS BEGUN TO TRANSLATE INTO SERN CANADA THIS EVENING. COOLING ALOFT AND WEAK HEIGHT FALLS ALONG SRN PERIPHERY OF THIS IMPULSE WERE SUFFICIENT TO FOCUS A BAND OF TSTMS ALONG/AHEAD OF THE COLD FRONT ACROSS CNTRL WI TO NRN/CNTRL LWR MI THIS AFTN/EVE. TSTMS CONTINUE TO MOVE ESEWD WHILE BACKBUILDING SWWD INTO THE EXTREME INSTABILITY AXIS CHARACTERIZED BY MLCAPE TO 4500 J PER KG. VERTICAL SHEAR REMAINS SUFFICIENT FOR SUPERCELLS...THOUGH THE RELATIVELY DRY MID-LEVELS CONTINUES TO BE FAVORABLE FOR COLD POOL GENERATION. MODEST UNIDIRECTIONAL WLY FLOW REGIME WILL ENCOURAGE CELLS TO BOW AND DAMAGING WINDS /A FEW WITH WIND GUSTS AOA 65 KT/ WILL REMAIN POSSIBLE ALONG WITH LARGE HAIL /ISOLD HAILSTONES AOA 2 INCHES IN DIAMETER/. FARTHER SW...THE IA TSTM CLUSTER CONTINUES TO EVOLVE ALONG THE MS RVR WITHIN WEAK DIFFLUENT FLOW REGIME. SWRN FLANK OF THE MCS HAS A SUBSTANTIAL COLD POOL AND TSTMS APPEAR TO BE BACKBUILDING S AND SW INTO NERN MO. NRN FLANK HAS SHOWN A TENDENCY TO DEVELOP/MOVE MORE EWD AND MAY EVENTUALLY DEVELOP/LINK UP WITH THE ACTIVITY BACKBUILDING SWWD ALONG THE COLD FRONT FROM WI. UPSHOT WILL PROBABLY BE AN EXPANDING AREA OF TSTMS FROM NWRN-NRN IL. VERY STEEP LAPSE RATES ALOFT WILL LIKELY FOSTER VERY LARGE HAIL PRODUCTION ALONG WITH DAMAGING WIND GUSTS. ACTIVITY SHOULD GRADUALLY WEAKEN LATER TONIGHT AS IT SINKS SEWD INTO ECNTRL MO-CNTRL IL-NRN IND AND LAKE ERIE OWING TO STABILIZING BOUNDARY LAYER AND WEAKENING LOW-LEVEL FLOW REGIME. ...SWRN DESERTS... 00Z RAOB FROM TUCSON REVEALS A RELATIVELY STABLE SOUNDING WITH DOWNSLOPE ELY FLOW. MORE UNSTABLE AIR MASS RESIDES THROUGH THE LWR CO RVR VLY. EARLIER TSTM DEVELOPMENT ALONG THE HIGHER TERRAIN OF NWRN AZ CONTINUES TO PROPAGATE WWD TOWARD THE INSTABILITY AXIS AND WILL LIKELY CONTINUE TO THE CO RVR AND POSSIBLY PARTS OF THE LAS VEGAS VLY LATER THIS EVENING. FARTHER S...MCV CONTINUES TO ROTATE WWD THROUGH CNTRL PIMA COUNTY. TSTMS MAY YET DEVELOP OR EXPAND ALONG/AHEAD OF THE VORT TRACK THROUGH SWRN AZ THROUGH THE EVENING. ANY TSTM ACROSS THE SWRN DESERTS WILL BE CAPABLE OF DAMAGING WINDS/DUST STORMS. ...NRN NY INTO NWRN NEW ENGLAND... THERE WILL BE A LOW PROBABILITY OF TSTMS WITH ISOLD DAMAGING WIND GUSTS APPROACHING NRN NY INTO NWRN NEW ENGLAND VERY LATE TONIGHT. UPSTREAM TSTM CLUSTERS CONTINUE TO EVOLVE OVER SRN ONT AND QUE. STRONGER FORCING ALOFT AND ATTENDANT SWLY LLJ WILL TRANSLATE NEWD THROUGH SERN CANADA OVERNIGHT. THERE IS SOME CONCERN THAT STRONGER BOW ECHOES MAY BE MAINTAINED OVERNIGHT AND APPROACH THE INTERNATIONAL BORDER FROM ME TO NRN NY STATE BY 12Z. ..RACY.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 06:09:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 02:09:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 180605 SWODY1 SPC AC 180603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT TUE JUL 18 2006 VALID 181200Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NERN STATES WWD INTO THE OH VLY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN SD INTO WRN MN... ...SYNOPSIS... PRIMARY WLYS WILL REMAIN ALONG THE CANADIAN BORDER THROUGH TUE. TWO SHORTWAVE TROUGHS WILL MOVE EWD WITHIN THE FLOW. THE LEAD TROUGH... CURRENTLY MOVING ACROSS THE GRTLKS REGION WILL MOVE ACROSS QUE AND ACROSS THE ST. LAWRENCE VLY AND NRN NEW ENGLAND TUE AFTN. THE UPSTREAM IMPULSE WILL MOVE ACROSS THE SRN CANADIAN PRAIRIES. IN THE LWR LVLS...A COLD FRONT WILL MOVE SEWD ACROSS NEW ENGLAND AND THE OH VLY. WRN END OF THE FRONT WILL BEGIN TO LIFT NWD DURING TUE NIGHT AS A LOW DEVELOPS EWD FROM THE HIGH PLAINS INTO PARTS OF THE DAKS. MEANWHILE...A SECONDARY COLD FRONT WILL BEGIN TO SWING EWD INTO THE DAKS BY LATE TUE AFTN. ...NERN STATES/MID-UPPER OH VLY... A MOIST BOUNDARY LAYER...CHARACTERIZED BY DEW POINTS IN THE UPPER 60S TO LOWER 70S...WILL REMAIN IN PLACE ALONG/SOUTH OF THE COLD FRONT ON TUE. ATOP THIS MOISTURE...A PLUME OF STEEP H7-H5 LAPSE RATES OF 7-7.5 DEG C PER KM EMANATING FROM THE PLAINS WILL EXIST. THIS ELEVATED MIXED LAYER WILL LIKELY DELAY CONVECTIVE INITIATION UNTIL AFTN. BUT...COMBINATION OF STRONG HEATING...WEAK HEIGHT FALLS AND CONVERGENCE ALONG THE COLD FRONT/PRE-FRONTAL TROUGHS...CINH SHOULD ERODE SUFFICIENTLY FOR TSTMS INITIATION FROM ME SWWD INTO NRN OH BY MID-AFTN. THE STRONGER DEEP LAYER SHEAR WILL EXIST ALONG THE BASE OF THE H5 TROUGH ACROSS NY EWD INTO NEW ENGLAND WHERE 40-50 KTS OF FLOW SHOULD BE COMMON. WLY UNIDIRECTIONAL NATURE TO THE FLOW WILL BE SUFFICIENT FOR SUPERCELLS...BUT EVOLUTION INTO BOWING LINE SEGMENTS WILL LIKELY OCCUR QUICKLY...GIVING DAMAGING WIND GUSTS ALONG WITH LARGE HAIL. THERE ARE SOME UNCERTAINTIES REVOLVING AROUND FRONTAL TIMING AND ANTICIPATED COVERAGE OF THE STORMS. ONCE MORE CONFIDENCE IS GAINED...AN UPGRADE TO CATEGORICAL MODERATE RISK MAY BE NEEDED. FARTHER SW...VERTICAL SHEAR WILL BE MUCH WEAKER...BUT MAGNITUDE OF LAPSE RATES/HOT BOUNDARY LAYER WILL BE FAVORABLE FOR MICROBURSTS AND PERHAPS AN ISOLD SUPERCELL OR TWO WITH LARGE HAIL FROM PARTS OF PA WWD INTO OH. ...LWR OH VLY... REGION WILL REMAIN BENEATH DIFFLUENT UPPER FLOW REGIME THROUGH TUE. VERY UNSTABLE CONDITIONS WILL DEVELOP ACROSS THE LWR OH VLY OWING TO RICH BOUNDARY LAYER MOISTURE AND STEEP MID-LEVEL LAPSE RATES. REMNANT OUTFLOW BOUNDARIES/COLD FRONT WILL BE MOVING SWD THROUGH PARTS OF IND WWD INTO PARTS OF MO AND COULD BE IMPETUS FOR TSTMS BY LATE AFTN. MAIN LIMITING FACTORS FOR STORMS WILL BE THE WARM TEMPERATURES ALOFT. HOWEVER...GIVEN A STORM...LARGE HAIL AND DAMAGING WINDS WILL BE LIKELY. ...GULF COASTAL REGION... UPPER SHEAR AXIS WILL REMAIN ACROSS THE GULF COASTAL REGION ON TUE AND TSTMS SHOULD FORM IN ASSOCIATION WITH THIS FEATURE AGAIN TUE AFTN. SATL SHOWS A CONSIDERABLE AMOUNT OF DRY AIR ENTRAINING INTO THIS FEATURE ATOP RICH BOUNDARY LAYER MOISTURE. THIS SUGGESTS THAT ISOLD MICROBURSTS MAY OCCUR WITH THE STRONGER STORMS ANYWHERE ALONG THE GULF COAST. ...FOUR CORNERS REGION... TSTMS WILL LIKELY FORM BENEATH UPPER RIDGE AXIS...WITH HIGHEST PROBABILITIES ACROSS THE FOUR CORNERS REGION. TROPOSPHERIC FLOW WILL BE LIGHT AND PULSE MULTICELL CLUSTERS WILL BE THE MAIN CONVECTIVE MODE. TYPICALLY DRY SUB-CLOUD LAYER COULD CONTRIBUTE TO ISOLD STORMS PRODUCING DAMAGING WIND GUSTS. ...NRN PLAINS... A STRONG EML WILL CONTINUE FROM THE ROCKIES INTO THE PLAINS TUE. THIS SHOULD EFFECTIVELY CAP SFC BASED PARCELS. BUT...HIGH BASED CONVECTION IS APT TO INCREASE OFF THE HIGHER TERRAIN. AS THE WARM FRONT LIFTS NWD ACROSS THE LWR/MIDDLE MO RVR VLY DURING LATE AFTN/OVERNIGHT...MOISTURE ADVECTION WILL INCREASE ALONG AN ACCELERATING SLY LLJ BENEATH THE EML. AS A RESULT...SOME OF THE AFTN CONVECTION MAY EVOLVE INTO AN MCS OVERNIGHT ACROSS PARTS OF SD INTO MN...OR ALONG THE EDGE OF THE STRONGER CAP. EFFECTIVE SHEAR WILL BE INCREASING OVERNIGHT AND GIVEN MAGNITUDE OF LAPSE RATES/ELEVATED CAPE...A FEW STORMS MAY PRODUCE LARGE HAIL AND PERHAPS GUSTY WINDS. ..RACY/JEWELL.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 12:43:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 08:43:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 181240 SWODY1 SPC AC 181238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT TUE JUL 18 2006 VALID 181300Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND SWWD ACROSS THE OHIO VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE NRN PLAINS... ...SYNOPSIS... LARGE UPPER RIDGE WILL DOMINATE THE WEATHER ACROSS MOST OF THE CONUS...WITH THE STRONGER MID LEVEL WINDS RESTRICTED TO THE NRN BORDER STATES. WITHIN THESE WESTERLIES...ONE SHORTWAVE TROUGH WILL MOVE FROM THE GREAT LAKES INTO NEW ENGLAND...WHILE A SECOND SYSTEM MOVES FROM OREGON INTO THE NRN ROCKIES. IN ASSOCIATION WITH THE LEAD TROUGH...A COLD FRONT WILL MOVE SEWD ACROSS NEW ENGLAND/OH VALLEY AND REMAIN QUASI-STATIONARY ACROSS THE MID MS VALLEY. THE WRN END OF THE FRONT WILL LIFT NWD FROM KS INTO NEB TONIGHT AS AN AREA OF LOW PRESSURE DEVELOPS ACROSS THE NRN PLAINS. ...NEW ENGLAND AND NY... ALTHOUGH ELEVATED STORMS ARE NOW MOVING THROUGH WRN ME... RELATIVELY WARM TEMPERATURES ALOFT ARE LIKELY TO INHIBIT SURFACE BASED CONVECTIVE DEVELOPMENT UNTIL LATE MORNING/EARLY AFTERNOON. THIS MEANS STRONGER CONVECTION IS MORE LIKELY LATER TODAY FROM CENTRAL ME SWWD INTO LOWER NY. ONCE SURFACE BASED STORMS DEVELOP ...THEY WILL BE ABLE TO INGEST STRONG INSTABILITY WITH MLCAPES FROM 2000-3000 J/KG. THIS INSTABILITY AND 40-50 KT DEEP LAYER SHEAR WILL SUPPORT SUPERCELLS. HOWEVER...THE DEEP UNDIRECTIONAL WLY WINDS THROUGHOUT THE TROPOSPHERE ARE LIKELY TO EVOLVE STORMS INTO LINES/BOWS...WITH WIND DAMAGE THE PRIMARY THREAT. ALTHOUGH UNCERTAINTY EXISTS ON WHEN/WHERE STORMS ARE MOST FAVORED...A HIGHER WIND POTENTIAL IS EXPECTED ACROSS THE ERN PORTIONS OF NEW ENGLAND SINCE THE FRONT/STORMS SHOULD PUSH THROUGH THESE AREAS DURING THE TIME OF MAX HEATING/INSTABILITY. THE SEVERE THREAT SHOULD END BY MID EVENING AS THE STORMS MOVE OFFSHORE. ...PA/OH AND MID MS VALLEYS... COLD FRONT/OUTFLOW BOUNDARY EXTEND FROM WRN NY TO A WEAK WAVE LOCATED IN NORTH CENTRAL IL...AND THEN SWWD INTO NRN MO. ELEVATED CONVECTION HAD DEVELOPED OVER CENTRAL IL THIS MORNING WITHIN INSTABILITY AXIS AND ZONE OF WEAK WARM ADVECTION...BUT STORMS SHOULD WEAKEN THIS MORNING AS WARM ADVECTION CEASES. MORE INTENSE CONVECTION IS EXPECTED TO DEVELOP THIS AFTERNOON ALONG THE WEAK COLD FRONT/REMNANT OUTFLOW BOUNDARIES. STRONG DAYTIME HEATING... STEEP MID LEVEL LAPSE RATES AND A MOIST BOUNDARY LAYER WILL RESULT IN MLCAPES TO RANGE FROM 2000 J/KG OVER PA/OH TO NEARLY 4000 J/KG ACROSS SRN IL/EAST CENTRAL MO. WARM MID LEVEL TEMPERATURES SHOULD LIMIT WRN EXTENT OF CONVECTIVE DEVELOPMENT TO ERN MO/IL...BUT MOST INTENSE CONVECTION SHOULD BE LOCATED ON THE ERN EDGE OF THIS CAP. ONCE STORMS DEVELOP...THE AMOUNT OF INSTABILITY AND 25-30 KT DEEP LAYER SHEAR WILL FAVOR MULTICELL STORM CLUSTERS WITH HAIL AND WIND DAMAGE. ...NRN PLAINS... TIMING AND LOCATION OF SEVERE CONVECTION IS QUESTIONABLE DUE TO SUBTLE DIFFERENCES IN THE CURRENT AND PAST ETA/GFS MODEL RUNS. HOWEVER...MODELS GENERALLY SUPPORT A LOW LEVEL JET/WARM ADVECTION DEVELOPING OVERNIGHT ACROSS THE ERN DAKOTAS/WRN MN AS A SHORTWAVE TROUGH MOVES INTO THE NRN ROCKIES. THE BOUNDARY LAYER WILL BE STRONGLY CAPPED...BUT STEEP LAPSE RATES ABOVE THE INVERSION WILL BE FAVORABLE FOR ELEVATED CONVECTION TO DEVELOP AFTER 03-06Z. EFFECTIVE SHEAR WILL BE INCREASING OVERNIGHT AND THE STEEP LAPSE RATES/ELEVATED CAPE MAY SUPPORT STORMS WITH SEVERE HAIL. ...GULF COASTAL REGION... NUMEROUS THUNDERSTORMS WERE LOCATED OFF THE LA COAST THIS MORNING IN ASSOCIATION WITH A WEAK SHEAR AXIS ALOFT. STORMS SHOULD DEVELOP INLAND LATER THIS MORNING AND AFTERNOON AND ALTHOUGH THE DEEP LAYER SHEAR IS WEAK...STRONG INSTABILITY AND HOT TEMPERATURES WILL SUPPORT SHORT-LIVED MICRO BURSTS. ...FOUR CORNERS REGION... MID/HIGH LEVEL MOISTURE TRAPPED UNDER UPPER RIDGE WILL LIKELY RESULT IN NUMEROUS DIURNAL THUNDERSTORMS. ENVIRONMENTAL WINDS/ SHEAR WILL BE WEAK...BUT A RELATIVELY DRY AND DEEP BOUNDARY LAYER MAY SUPPORT A FEW STRONG WINDS GUSTS. ..IMY/JEWELL.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 16:42:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 12:42:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 181639 SWODY1 SPC AC 181638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT TUE JUL 18 2006 VALID 181630Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FROM CENTRAL MO ACROSS THE OH VALLEY INTO NEW ENGLAND.... ...OH VALLEY TO NEW ENGLAND TODAY... A MID LEVEL TROUGH EXTENDING FROM NRN IL TO THE SAINT LAWRENCE VALLEY...ALONG WITH AN ASSOCIATED SURFACE COLD FRONT AND PRE-FRONTAL TROUGH...WILL MOVE EWD OVER THE OH VALLEY AND NEW ENGLAND BY TONIGHT. STRONG SURFACE HEATING NEAR AND E OF THE PRE-FRONTAL TROUGH...BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S TO LOWER 70S...AND STEEP LOW-MID LEVEL LAPSE RATES WILL RESULT IN MLCAPE VALUES OF 1500-2500 J/KG. EXPECT THUNDERSTORM DEVELOPMENT TO OCCUR FROM MIDDAY INTO EARLY AFTERNOON AS SURFACE HEATING/MIXING REMOVES CONVECTIVE INHIBITION FROM CENTRAL PA NEWD ACROSS SRN NEW ENGLAND INTO SRN/ERN MAINE. ROUGHLY 40 KT WSWLY FLOW IN THE 700-500 MB LAYER WILL COMBINE WITH THE STEEP LOW-LEVEL LAPSE RATES AND LARGE DCAPE VALUES /GREATER THAN 1000 J/KG/ TO SUPPORT A THREAT FOR DAMAGING WINDS WITH THE STRONGER CELLS/BOWING SEGMENTS. LARGE HAIL WILL ALSO BE POSSIBLE GIVEN THE STEEP MID LEVEL LAPSE RATES LARGE MLCAPE. ...MO/IL THIS AFTERNOON/EVENING... THE SURFACE COLD FRONT EXTENDS WWD INTO IL/MO/KS...WITH A WEAK SURFACE LOW JUST N OF STL. BOUNDARY LAYER DEWPOINTS REMAIN IN THE MID 70S ALONG AND S OF THE FRONT...THOUGH EARLY STORMS ACROSS SRN IL HAVE TEMPORARILY DELAYED SURFACE HEATING. STILL...CLEARING OF THE CLOUDS WILL ALLOW AFTERNOON TEMPERATURES TO WARM INTO THE 90S FROM CENTRAL MO TO CENTRAL IL...WHICH WILL RESULT IN MLCAPE VALUES OF 2500-4000 J/KG. THOUGH LOW-LEVEL SHEAR IS RELATIVELY WEAK OVER THIS AREA...30 KT NWLY MID LEVEL FLOW COULD RESULT IN SUFFICIENT DEEP LAYER SHEAR FOR ORGANIZED MULTICELL CLUSTERS OR STORMS WITH SOME SUPERCELL STRUCTURES. THE STRONG INSTABILITY WILL SUPPORT A THREAT FOR DAMAGING OUTFLOW WINDS AND LARGE HAIL LATER THIS AFTERNOON/EVENING. ...NRN PLAINS... WATER VAPOR IMAGERY FEATURES MID LEVEL SPEED MAXIMA MOVING EASTWARD FROM ERN MT INTO THE DAKOTAS AT MIDDAY. IN THE WAKE OF ONGOING ELEVATED TSTMS ACROSS SRN ND/NRN SD...STRONG INSOLATION/HEATING WILL LEAD TO A MODESTLY UNSTABLE/WEAKLY CAPPED BOUNDARY LAYER THIS AFTERNOON. ISOLATED STRONG STORMS CAPABLE OF STRONG WIND GUSTS/SOME HAIL WILL LIKELY DEVELOP ALONG THE LEE TROUGH/ADVANCING COLD FRONT THIS AFTERNOON/EARLY EVENING. LATER TONIGHT...NUMERICAL MODEL GUIDANCE GENERALLY SUPPORTS THE DEVELOPMENT OF A 40 KT LOW LEVEL JET/WARM ADVECTION REGIME OVERNIGHT ACROSS THE ERN DAKOTAS/WRN MN. STEEP LAPSE RATES ABOVE A CAPPED BOUNDARY LAYER WILL BE FAVORABLE FOR AT LEAST ISOLATED ELEVATED CONVECTION TO DEVELOP AFTER 03-06Z. GIVEN SUFFICIENT CLOUD BEARING SHEAR AND PRESENCE OF STEEP LAPSE RATES/ELEVATED CAPE...THE STRONGEST STORMS MAY BE CAPABLE OF SEVERE HAIL OVERNIGHT. ...GULF COAST REGION... NUMEROUS THUNDERSTORMS CONTINUE AT MIDDAY ALONG THE TX UPPER COASTAL PLAIN IN ASSOCIATION WITH A WESTWARD MOVING WEAK SHEAR AXIS ALOFT. GIVEN DIURNAL HEATING...STORMS SHOULD DEVELOP INLAND THROUGH THE AFTERNOON...NAMELY FROM THE MIDDLE TX COAST/SOUTHEAST TX INTO THE CENTRAL GULF COAST STATES AND FL PENINSULA. ALTHOUGH THE DEEP LAYER SHEAR IS WEAK...STRONG INSTABILITY AND HOT TEMPERATURES WILL SUPPORT THE POTENTIAL FOR SHORT-LIVED MICROBURSTS CAPABLE OF STRONG WIND GUSTS. ...FOUR CORNERS REGION... MID/HIGH LEVEL MOISTURE REMAINS BENEATH UNDER UPPER RIDGE...WITH NUMEROUS DIURNAL THUNDERSTORMS LIKELY THIS AFTERNOON. AMBIENT VERTICAL SHEAR WILL BE WEAK...LIMITING SEVERE STORM ORGANIZATION/LONGEVITY. NEVERTHELESS...A RELATIVELY DRY AND DEEPLY MIXED BOUNDARY LAYER WILL SUPPORT A FEW STRONG WINDS GUSTS/PERHAPS HAIL. ..THOMPSON/GUYER.. 07/18/2006  From swody1 at goshenarc.org Tue Jul 18 20:03:26 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 16:03:26 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 182000 SWODY1 SPC AC 181958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT TUE JUL 18 2006 VALID 182000Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND ACROSS THE MIDDLE ATLANTIC STATES INTO THE MIDDLE MS VALLEY... ...NERN STATES INTO THE MIDDLE MS VALLEY... UPPER TROUGH FROM QUEBEC SWWD ACROSS THE LOWER GREAT LAKES IS EXPECTED TO CONTINUE MOVING EWD THROUGH TONIGHT. ERN PART OF THE ASSOCIATED SURFACE COLD FRONT CURRENTLY FROM SRN ME SWWD INTO CENTRAL PA AND CENTRAL IL WILL MOVE SEWD ACROSS THE MID ATLANTIC STATES...WHILE WRN PORTION OF THE FRONT MOVES MORE SLOWLY ACROSS THE OH VALLEY. A VERY WARM/MOIST LOW LEVEL AIR MASS IS PRESENT ALONG/AHEAD OF THE FRONT WITH SURFACE TEMPERATURES GENERALLY IN THE UPPER 80S/LOWER 90S AND DEW POINTS IN THE UPPER 60S TO LOWER 70S...WITH HIGHER DEW POINTS IN THE MID/UPPER 70S NOTED OVER PARTS OF IL/ERN MO. THE HIGH THETA-E AIR MASS IS CONTRIBUTING TO A MODERATELY TO VERY UNSTABLE ENVIRONMENT WITH MLCAPE RANGING FROM 1500-2500 J/KG FROM SRN NEW ENGLAND ACROSS THE MIDDLE ATLANTIC STATES INTO THE OHIO VALLEY TO 3000-4000 J/KG IN THE MIDDLE MS VALLEY. STRONG/SEVERE THUNDERSTORMS HAVE DEVELOPED OVER NRN NEW ENGLAND...WITH ADDITIONAL CLUSTERS OVER PA...ERN WV...AND WRN OH. VISIBLE SATELLITE IMAGERY INDICATES ENHANCED CU/TCU ALONG THE FRONT CENTRAL PA INTO EAST CENTRAL OH SUGGESTING NEW THUNDERSTORMS MAY DEVELOP SOON ACROSS THIS AREA. ALTHOUGH STRONGER DEEP LAYER SHEAR OF 30-40 KT EXISTS FROM NY INTO NEW ENGLAND...MODERATE SHEAR OF 20-30 KT ACROSS THE DELMARVA/PA/OH AREA SHOULD BE SUFFICIENT TO ENHANCE CONVECTIVE ORGANIZATION AND SUPPORT A FEW SEVERE STORMS CAPABLE OF PRODUCING DAMAGING WIND GUSTS AND LARGE HAIL INTO THE EVENING HOURS. FARTHER WEST...VISIBLE IMAGERY SHOWS A DEVELOPING CU FIELD NEAR A SURFACE LOW OVER SOUTH CENTRAL IL. CONTINUED HEATING COUPLED WITH HIGH SURFACE DEW POINTS AND DRYING ALOFT ARE COMBINING TO PRODUCE VERY UNSTABLE CONDITIONS. HOWEVER...THE DRYING/SUBSIDENCE ALOFT ALSO APPEARS TO BE INHIBITING DEEP CONVECTIVE INITIATION ATTM. AS THE CAP CONTINUES TO WEAKEN...A FEW PARCELS MAY REACH THE LFC WITH SUBSEQUENT RAPID THUNDERSTORM DEVELOPMENT POSSIBLE. NWLY MID LEVEL WINDS OF 25 KT WILL PROVIDE SUFFICIENT DEEP LAYER SHEAR FOR SEVERE THUNDERSTORMS TO DEVELOP. VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE WITH ANY PERSISTENT UPDRAFTS THAT CAN DEVELOP. ...GULF COAST REGION... SCATTERED CONVECTION HAS DEVELOPED FROM AL AND EXTREME WRN GA SWWD ACROSS MS/LA INTO SERN TX. 20-30 DEG F TEMPERATURE/DEW POINT SPREADS AT THE SURFACE COUPLED WITH STEEP LOW LEVEL LAPSE RATES AND PRONOUNCED DRYING IN THE MID/UPPER LEVELS INDICATES POTENTIAL FOR A FEW WET MICROBURSTS TO OCCUR. ...PARTS OF CA/WRN NV... VISIBLE IMAGERY SHOWS A WELL-DEFINED MESOSCALE CONVECTIVE VORTEX MOVING NWWD INTO CENTRAL CA. THIS MAY ENHANCE THUNDERSTORM DEVELOPMENT ACROSS THIS REGION LATER THIS AFTERNOON AND EVENING. ...NRN PLAINS... WEAK ELEVATED CONVECTION HAS MOVED EWD ACROSS NRN SD...WITH CLEAR SKIES AND STRONG INSOLATION OCCURRING IN ITS WAKE OVER THE NRN PLAINS. AN ELEVATED MOISTURE RETURN WILL INCREASE TONIGHT IN RESPONSE TO A STRENGTHENING SOUTHERLY LOW LEVEL JET. THIS SUGGESTS POTENTIAL FOR ELEVATED THUNDERSTORMS TO DEVELOP DURING THE OVERNIGHT HOURS OVER PARTS OF THE DAKOTAS WHICH MAY BE CAPABLE OF PRODUCING HAIL WITH STRONGER STORMS. CONVECTIVE COVERAGE APPEARS TO BE TOO LIMITED TO WARRANT A SLIGHT RISK AREA. ..WEISS.. 07/18/2006  From swody1 at goshenarc.org Wed Jul 19 01:09:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 18 Jul 2006 21:09:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190106 SWODY1 SPC AC 190104 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0804 PM CDT TUE JUL 18 2006 VALID 190100Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SRN NEW ENGLAND SWWD TO PARTS OF THE MID-ATLANTIC REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LWR OH VLY WWD INTO SERN MO... ...SRN NEW ENGLAND SWD TO DELMARVA... LATEST MESOANALYSIS PLACES THE STRONGEST INSTABILITY AXIS /MLCAPES 1500-2500 J PER KG/ EXTENDING FROM SOUTH OF THE MASS TURNPIKE SWWD INTO NEW YORK CITY AND THEN INTO THE DELMARVA REGION. THE SEABREEZE HAS PENETRATED INLAND ACROSS EXTREME SERN NEW ENGLAND WHERE 00Z CHH SOUNDING EXHIBITED A SHALLOW MARINE LAYER. MAJORITY OF THE TSTMS HAVE EVOLVED FROM SWRN CT SWWD INTO MD EARLY THIS EVE WHERE THE BOUNDARY LAYER WAS THE HOTTEST/MOST UNSTABLE TODAY. THOUGH THE STRONGEST DEEP LAYER SHEAR WAS RELEGATED TO AREAS NORTH OF NEW YORK CITY...THE VERY STEEP LAPSE RATES AND WLY...LARGELY UNIDIRECTIONAL FLOW HAS BEEN FAVORABLE FOR TSTM LINE SEGMENTS TO BOW GIVING DAMAGING WIND GUSTS. THROUGH THE REMAINDER OF THE EVENING...STRONGER STORMS SHOULD CONTINUE EWD THROUGH PARTS OF EXTREME SERN PA...NJ...DE AND LWR MD. TSTMS MAY TEND TO WEAKEN ACROSS SRN NEW ENGLAND/LONG ISLAND AS THE STORMS ENCOUNTER THE MARINE LAYER. DAMAGING WINDS AND LARGE HAIL WILL BE THE PRIMARY SEVERE THREATS. SEVERE WEATHER PROBABILITIES WILL DECREASE LATER THIS EVENING. ...LWR OH VLY WWD INTO SERN MO... A COUPLE STRONG-SEVERE TSTM CLUSTERS CONTINUE TO PROPAGATE SWWD ACROSS PORTIONS OF THE LWR OH VLY AND SERN MO BENEATH DIFFLUENT UPPER FLOW REGIME. THE IND STORMS APPEAR TO HAVE DEVELOPED ALONG THE SYNOPTIC COLD FRONT EARLY IN THE AFTN AND ARE THRIVING ON VERY UNSTABLE PARCELS...MLCAPE TO 2500 J PER KG. FARTHER SW...TSTMS THAT DEVELOPED SOUTH OF KSTL PROBABLY FORMED ALONG RESIDUAL OUTFLOW BOUNDARIES FROM EARLY DAY ACTIVITY. THESE STORMS ARE ALSO EMBEDDED WITHIN A VERY UNSTABLE ENVIRONMENT WITH MLCAPE TO 3500 J PER KG. ACTIVITY WILL GRADUALLY WEAKEN AS CINH INCREASES BY LATE EVE. UNTIL THEN...VERTICAL SHEAR OF 40-45 KTS AND MAGNITUDE OF LAPSE RATES/INSTABILITY SUGGEST THAT LARGE HAIL AND DAMAGING WIND GUSTS WILL BE POSSIBLE. AN ISOLD TORNADO IS ALSO NOT OUT OF THE QUESTION. ...SWRN DESERTS... CONVECTIVE COVERAGE HAS INCREASED OVER THE PAST SEVERAL DAYS ACROSS THE SWRN DESERTS...PARTICULARLY OVER THE SCNTRL AZ DESERTS. THIS MAY BE DUE TO SLIGHTLY MORE FAVORABLE UPPER AIR DIVERGENCE ALONG THE BACKSIDE OF DEPARTING UPPER LOW. THE STRONGEST TSTM CLUSTER WILL LIKELY CONTINUE NEAR/S OF THE KPHX METRO AREA SWD TO CNTRL/WRN PIMA COUNTY THROUGH THE EVE HOURS. HAIL AND GUSTY WINDS/DUST STORMS WILL ACCOMPANY THE STORMS. ...NRN PLAINS... ELEVATED MOISTURE RETURN WILL INCREASE TONIGHT IN RESPONSE TO A STRENGTHENING SOUTHERLY LOW LEVEL JET ACROSS PORTIONS OF THE NRN PLAINS. THIS SUGGESTS THE POTENTIAL FOR ELEVATED THUNDERSTORMS TO DEVELOP DURING THE OVERNIGHT HOURS OVER PARTS OF THE DAKS WHICH MAY BE CAPABLE OF PRODUCING HAIL OR GUSTY WINDS WITH STRONGER STORMS. ANTICIPATED CONVECTIVE COVERAGE APPEARS TO BE TOO LIMITED TO WARRANT A SLGT RISK AREA. ..RACY.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 05:55:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 01:55:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 190552 SWODY1 SPC AC 190551 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1251 AM CDT WED JUL 19 2006 VALID 191200Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS CENTRAL AND SOUTHEASTERN MN...CENTRAL AND SOUTHERN WI AND A SMALL PART OF NORTHEAST IA... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN PARTS OF THE NRN PLAINS EWD ACROSS THE UPPER MS VLY TO THE CNTRL GRTLKS... ...SYNOPSIS... STRONGER WLYS WILL REMAIN ALONG THE NRN TIER OF THE COUNTRY ON WED AS THE UPPER RIDGE AXIS CONTINUES ACROSS THE CNTRL PARTS OF THE PLAINS AND ROCKIES. A SHORTWAVE TROUGH...EMBEDDED WITHIN A WEAKER SUBTROPICAL JET S OF THE PRIMARY WLYS OVER THE NRN ROCKIES...WILL PROGRESS ESEWD REACHING THE UPPER MS VLY/UPPER GRTLKS BY THE END OF THE PERIOD. AT THE SFC...AN ASSOCIATED COLD FRONT WILL MOVE EWD ACROSS THE NRN PLAINS AND UPPER MS VLY...REACHING A WRN LAKE SUPERIOR/SWRN MN/NRN NEB LINE BY 20/00Z...AND CONTINUING TO ERN LAKE SUPERIOR/SWRN WI/SWRN IA BY THE END OF THE PERIOD. MEANWHILE...A WARM FRONT WILL LIFT RAPIDLY NWD ACROSS THE UPPER MS VLY DURING THE MORNING WITH A VERY MOIST WARM SECTOR DEVELOPING BY AFTN. ...UPPER MS VLY/CNTRL GRTLKS... TUE EVENING UPPER AIR ANALYSIS SHOWS A STRONG WARM PLUME OF AIR STREAMING EWD FROM THE CNTRL HIGH PLAINS TOWARD THE MO RVR VLY WITH H7 TEMPERATURES IN EXCESS OF 16 DEG C AT KLBF. THIS ELEVATED MIXED LAYER /EML/ WILL SPREAD INTO AT LEAST IA BY WED AFTN. TO THE N OF THIS CAP...CONSIDERABLE ELEVATED CONVECTION IS EXPECTED TO BE ONGOING WED MORNING FROM THE DAKOTAS EWD INTO NWRN MN. STORMS MAY ALREADY BE PRODUCING LARGE HAIL AT THAT TIME. THIS ACTIVITY MAY PERSIST/DEVELOP EWD ACROSS NRN MN AND INTO THE UPPER GRTLKS LATER IN THE DAY WITH RISKS FOR DAMAGING WINDS AS WELL. ATTENTION WILL THEN TURN TO A RATHER ACTIVE AFTN AND EVENING FROM PARTS OF CNTRL/SRN MN INTO THE CNTRL GRTLKS. BOUNDARY LAYER MOISTURE IS EXPECTED TO RAPIDLY RETURN NWD BENEATH THE EML AND BY AFTN UPPER 60S TO MID 70S F/MID-TEENS C SFC/H85 DEW POINTS WILL BE COMMON ACROSS THE UPPER MS VLY. STRONG HEATING WILL CONTRIBUTE TO A VERY TO EXTREMELY UNSTABLE AIR MASS. STRONGEST CAP WILL HOLD ACROSS SWRN MN AND IA...BUT AS LARGE SCALE ASCENT ASSOCIATED WITH THE TROUGH SPREADS EWD...THE CAP SHOULD WEAKEN ACROSS CNTRL/SRN MN BY MID-AFTN. AS A RESULT...TSTMS SHOULD DEVELOP ALONG/AHEAD OF THE COLD FRONT AND EWD ALONG THE WARM FRONT MID-LATE AFTN FROM CNTRL MN EWD INTO PARTS OF WI. VERTICAL SHEAR PROFILES WILL BECOME STRONGER THROUGH THE LATE AFTN AS A 50-70 KT H5 JET MOVES ACROSS THE REGION...BOOSTING 0-6KM VALUES IN THE 60-70 KT RANGE. GIVEN THE MAGNITUDE OF LAPSE RATES...INITIAL TSTMS WILL GROW INTO SUPERCELLS WITH VERY LARGE HAIL AND DAMAGING WINDS. HODOGRAPHS BECOME QUITE LARGE VCNTY THE WARM FRONT FROM CNTRL/SRN MN ACROSS SWRN WI AS A SWLY LLJ OF 40 KTS BECOMES JUXTAPOSED WITH THE 70 KT WNWLY H5 JET DURING THE LATE AFTN. LOW LCLS AND STRONG LOW-LEVEL SHEAR WILL BE FAVORABLE FOR A FEW TORNADOES WITH THE INITIAL SUPERCELLS...PRIMARILY ALONG THE WARM FRONT. EVOLUTION INTO A FORWARD PROPAGATING BOW ECHO/DERECHO APPEARS LIKELY DURING THE EVENING AS THE LLJ VEERS WLY AND BECOMES ALIGNED WITH THE WNWLY 70 KT H5 JET. THIS WILL INCREASE THE DAMAGING WIND RISK INTO WI AND POSSIBLY AS FAR E AND S AS PARTS OF LWR MI AND NRN IND/IL BY 12Z THU. ADDITIONAL TSTMS WILL TEND TO BACKBUILD WWD INTO THE CAP ACROSS IA DURING THE OVERNIGHT WITH AN ATTENDANT RISK OF LARGE HAIL. ...CNTRL-SRN APPALACHIANS... WEAK BOUNDARIES WILL BE PRESENT ACROSS PARTS OF THE CNTRL-SRN APPALACHIANS WED. STRONG HEATING...AMPLE BOUNDARY LAYER MOISTURE AND WEAK UPSLOPE COMPONENT WILL CONTRIBUTE TO TSTMS DEVELOPING ESPECIALLY ALONG THE ERN SLOPES OF THE MOUNTAINS. MULTICELL STORM CLUSTERS MAY APPROACH/BRIEFLY EXCEED SEVERE LIMITS WITH DAMAGING WINDS THE PRIMARY THREAT THREAT. ...GULF COASTAL STATES... DIURNAL TSTMS...ENHANCED BY LOCAL CONVERGENCE FROM OUTFLOW BOUNDARIES/SEA BREEZE...WILL BE LIKELY ACROSS MOST OF THE GULF COASTAL REGION WED AFTN. THETA-E PROFILES WILL DECREASE RAPIDLY WITH HEIGHT AND SUGGESTS THAT ISOLD MICROBURSTS MAY ACCOMPANY THE PULSE MULTICELL STORM CLUSTERS. ...SWRN DESERTS... 00Z WED H5 CHART SUGGESTS THAT THE MID-TROPOSPHERE SHOULD WARM A DEGREE OR TWO OVER TUE READINGS ACROSS THE SWRN DESERTS. BUT...BOUNDARY LAYER MOISTURE MAY BE HIGHER THAN PREVIOUS DAYS OWING TO RECENT SLOW MOVING TSTMS. AS A RESULT...ANY TSTM THAT CAN MANAGE TO FORM MAY PRODUCE ISOLD DAMAGING WIND GUSTS. CONVECTIVE COVERAGE WILL BE HIGHLY MODULATED BY THE MAGNITUDE OF CLOUD DEBRIS THAT REMAINS OVER THE REGION FROM TUE EVE/OVERNIGHT TSTMS. ..RACY/TAYLOR.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 12:38:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 08:38:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191235 SWODY1 SPC AC 191234 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 AM CDT WED JUL 19 2006 VALID 191300Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF SERN MN...NERN IA AND SWRN WI... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MS RIVER VALLEY EWD TO THE GREAT LAKES... ...SYNOPSIS... WESTERLIES WILL REMAIN ACROSS THE NRN FOURTH OF THE COUNTRY...WHILE A LARGE UPPER RIDGE CONTINUES ITS HOLD OVER THE REST OF THE NATION. THE MAJOR FEATURE FOR SEVERE CONVECTION WILL BE A SHORTWAVE TROUGH...ASSOCIATED 60-70 KT MID LEVEL JET MAX AND COLD FRONT MOVING FROM THE DAKOTAS EWD INTO THE WESTERN GREAT LAKES DURING THIS PERIOD. A WARM FRONT ACROSS THE MO RIVER VALLEY WILL SHIFT NWD INTO SRN MN/WI THIS AFTERNOON. ...UPPER MS VLY/CNTRL GRTLKS... BAND OF ELEVATED THUNDERSTORMS IN WRN MN SHOULD SPREAD E/SEWD THIS MORNING AS THE LOW LEVEL JET VEERS. MUCAPES 2000+ J/KG AND STEEP LAPSE RATES INDICATE SEVERE HAIL IS POSSIBLE...BUT WARM MID LEVEL TEMPERATURES SHOULD LIMIT THE THREAT. EXPECT THE CLOUDS/PCPN FROM THIS COMPLEX WILL REINFORCE WARM FRONT ACROSS SRN MN THIS AFTERNOON. VERY WARM TEMPERATURES ALOFT...700 MB TEMPERATURES NEAR 16 DEG...INDICATE A STOUT CAP WILL ALSO BE IN PLACE. HOWEVER...THE COMBINATION OF LARGE SCALE LIFTING FROM TROUGH/JET MAX AND CONVERGENCE SHOULD AID RENEWED THUNDERSTORM DEVELOPMENT NEAR COLD FRONT/BOUNDARY INTERSECTION BETWEEN 19-22Z. ONCE STORMS FORM...THE AIR MASS WILL BE EXTREMELY UNSTABLE...MLCAPE VALUES IN EXCESS OF 4000 J/KG...AND WITH DEEP LAYER SHEAR NEAR 60 KT...RAPID DEVELOPMENT OF SUPERCELLS IS EXPECTED. THE BOUNDARY LAYER SHOULD BE QUITE MOIST NEAR THE WARM FRONT AND STRONGLY CURVED HODOGRAPHS IN THE LOWER 1 KM INDICATE A POTENTIAL FOR TORNADOES...ALONG WITH VERY LARGE HAIL. HOWEVER...THE STORMS SHOULD GENERATE STRONG OUTFLOWS THAT MERGE AND EVOLVE INTO A FORWARD PROPAGATING BOW ECHO/DERECHO AS THE LLJ BECOMES WLY AND ALIGNS WITH THE STRONG WINDS ALOFT. THE RESULTING COLD POOL SHOULD ALSO HELP DEVELOP A REAR INFLOW JET WITH WIDESPREAD DAMAGING WINDS POSSIBLE AS THE SYSTEM MOVES ESEWD ACROSS SERN MN/NERN IA/SWRN WI. THE LINEAR COMPLEX MAY CONTINUE MOVING SEWD OVERNIGHT INTO NRN IL AND LOWER MI...BUT THE STABILIZING BOUNDARY LAYER SHOULD DECREASE THE WIND THREAT. INTENSE HEATING AND FRONTAL CONVERGENCE MAY BE SUFFICIENT TO LIFT CAP FOR STORMS TO INITIATE ACROSS EXTREME SERN SD/NWRN IA AND NERN NEB BETWEEN 21-03Z. ANY STORMS THAT DEVELOP IN THIS DEEPLY MIXED BOUNDARY LAYER LIKELY WOULD PRODUCE STRONG/SEVERE WINDS. STORMS THAT DEVELOP SHOULD WEAKEN QUICKLY AFTER SUNSET AS THE CAP BECOMES REESTABLISHED. ...CNTRAL AND SRN APPALACHIANS... WEAK FRONT/BOUNDARY COMBINED WITH STRONG HEATING OF A MOIST BOUNDARY LAYER ACROSS THE CENTRAL/SRN APPALACHIANS SHOULD RESULT IN AFTERNOON THUNDERSTORM DEVELOPMENT. ENVIRONMENTAL WINDS WILL BE WEAK...BUT MODERATE INSTABILITY MAY SUPPORT A FEW DAMAGING WIND EVENTS. ...GULF COASTAL STATES... DIURNAL THUNDERSTORMS WILL ONCE AGAIN BE LIKELY ACROSS THE GULF COASTAL STATES WITH ISOLATED BRIEF WET MICROBURSTS POSSIBLE. ...SWRN DESERTS... WIDESPREAD CLOUDS AND A FEW THUNDERSTORMS WERE STILL OCCURRING ACROSS AZ THIS MORNING. STRONG HEATING OF THE RELATIVELY MOIST ENVIRONMENT SHOULD RESULT IN STORMS TO REDEVELOP THIS AFTERNOON. THE CONVECTIVE OVERTURNING OF STORMS THE PAST FEW DAYS AND WEAK WINDS ALOFT INDICATE THE THREAT FOR MORE THAN ISOLATED STRONG WIND GUSTS IS LIMITED. ..IMY/TAYLOR.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 16:31:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 12:31:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 191628 SWODY1 SPC AC 191626 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1126 AM CDT WED JUL 19 2006 VALID 191630Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON/EVENING ACROSS NRN IA...SRN WI...AND NRN IL... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON INTO TONIGHT ACROSS MOST OF THE UPPER MS VALLEY AND PARTS OF MI... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON ACROSS THE LOWER MS VALLEY... ...IA/MN/WI/IL THIS AFTERNOON/EVENING... A MID LEVEL SHORTWAVE TROUGH OVER THE NRN HIGH PLAINS WILL AMPLIFY SOME AND MOVE ESEWD TO THE UPPER MS VALLEY BY TONIGHT...WHILE AN ASSOCIATED SURFACE COLD FRONT MOVES SEWD FROM THE ERN DAKOTAS TO NW WI/CENTRAL IA/SRN NEB. THE SURFACE PATTERN IS COMPLICATED BY AN ONGOING MCS ACROSS SE MN/SW WI/NE IA. THIS CONVECTION DEVELOPED IN ASSOCIATION WITH LOW-LEVEL WAA AND A MID LEVEL SPEED MAX OVER NERN SD THIS MORNING. GIVEN THE WELL-DEVELOPED COLD POOL/BOW ECHO...MERGING CLUSTERS...AND A DESTABILIZING BOUNDARY LAYER IN ADVANCE OF THE STORMS...THE THREAT FOR DAMAGING WINDS APPEARS TO BE INCREASING ACROSS SRN WI AND NRN IL THIS AFTERNOON. OUTFLOW WITH THIS CONVECTION WILL ALSO MODULATE THE NWD PROGRESSION OF THE VERY UNSTABLE WARM SECTOR ACROSS IA/MN/WI. THE 12Z NAM REFLECTS THIS SCENARIO BY MAINTAINING THE ONGOING STORMS THROUGH THE DAY. HOWEVER...THIS MODEL APPEARS TO BE SEVERAL HOURS TOO SLOW WITH THE PROGRESSION OF THE MORNING STORMS. STRONG/EXTREME INSTABILITY IS EXPECTED ALONG THE TRAILING OUTFLOW BOUNDARY ACROSS IA...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS. ADDITIONAL CONVECTION MAY FORM ALONG THE OUTFLOW ACROSS NW/N CENTRAL IA BY MID-LATE AFTERNOON...AND THEN MOVE ESEWD ACROSS THE REMAINDER OF IA AND INTO NRN IL TONIGHT. THE INITIAL STORMS MAY BE SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND A FEW TORNADOES WHERE LOW-LEVEL MOISTURE/SHEAR ARE ENHANCED ALONG THE BOUNDARY. THIS CONVECTION MAY GROW UPSCALE THIS EVENING INTO ANOTHER FORWARD PROPAGATING MCS WITH DAMAGING WINDS. ...LOWER MS VALLEY THIS AFTERNOON... WATER VAPOR IMAGERY SHOWS A WEAK MID LEVEL WAVE MOVING SWWD OVER NE MS. THE COMBINATION OF THIS WEAK MID LEVEL DISTURBANCE AND A DIFFUSE SFC TROUGH SHOULD HELP FOCUS THE DEVELOPMENT OF SEVERAL MULTICELL THUNDERSTORM CLUSTERS THIS AFTERNOON. MODIFYING THE 12Z JAN SOUNDING FOR AFTERNOON SURFACE TEMPERATURES IN THE LOW-MID 90S...MLCAPE WILL APPROACH 3000 J/KG AND LAPSE RATES FROM THE SURFACE TO NEAR 500 MB WILL BE NEAR 8 C/KM. THE 12Z SHV SOUNDING SHOWS A SIMILAR ENVIRONMENT...WITH SOMEWHAT STRONGER /30 KT/ NELY MID LEVEL FLOW AND MODEST DEEP LAYER SHEAR. A FEW DAMAGING DOWNBURSTS SHOULD BE THE MAIN THREAT...THOUGH ISOLATED LARGE HAIL WILL ALSO BE POSSIBLE WITH THE MOST INTENSE STORMS. ..THOMPSON/GUYER.. 07/19/2006  From swody1 at goshenarc.org Wed Jul 19 20:10:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 16:10:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 192007 SWODY1 SPC AC 192005 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0305 PM CDT WED JUL 19 2006 VALID 192000Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS FROM NRN/ERN IA INTO NRN/CENTRAL IL... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MODERATE RISK FROM THE UPPER MS VALLEY INTO THE UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER MS VALLEY/GULF COAST STATES... ...IA INTO NRN IL/NWRN INDIANA... ONGOING SEVERE MCS MOVING INTO NWRN IL IS EXPECTED TO CONTINUE MOVING SEWD INTO VERY WARM/MOIST ENVIRONMENT CHARACTERIZED BY SURFACE TEMPERATURES NEAR 90 AND DEW POINTS IN THE LOW/MID 70S. THIS IS RESULTING IN MLCAPE OF 2500-4000 J/KG...AND WITH CONTINUED AFTERNOON HEATING FURTHER DESTABILIZATION IS LIKELY. NWLY MID LEVEL WINDS OF 25-30 KT ACROSS THIS REGION IS CONTRIBUTING TO DEEP LAYER SHEAR OF 20-30 KT...WHICH IS SUFFICIENT TO MAINTAIN MESOSCALE ORGANIZATION OF THE CONVECTIVE SYSTEM. VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL BE LIKELY AS THE STORMS MOVE SEWD 35 KT ACROSS PARTS OF NRN/CENTRAL IL THIS AFTERNOON. THIS SYSTEM MAY CONTINUE SEWD INTO PARTS OF WEST CENTRAL/SWRN INDIANA THIS EVENING BEFORE SLOWLY WEAKENING AS IT MOVES INTO A REGION OF LESS FAVORABLE SHEAR. THE CURRENT MCS MOVING INTO NWRN IL HAS GENERATED A CONVECTIVE OUTFLOW BOUNDARY EXTENDING DIAGONALLY FROM SERN INTO NWRN IA AND EXTREME SERN SD...WHERE IT INTERSECTS A NE/SW ORIENTED COLD FRONT EXTENDING FROM NRN MN INTO CENTRAL NEB. ALTHOUGH VISIBLE IMAGERY AND RUC FORECAST SOUNDINGS INDICATE THE LOW LEVEL AIR MASS IS CURRENTLY CAPPED OVER THIS REGION...PERSISTENT CONVERGENCE AND DYNAMIC FORCING ALONG THE SRN EDGE OF A SHORT WAVE TROUGH MOVING TOWARD THE UPPER MS VALLEY ARE EXPECTED TO WEAKEN THE CAP SUFFICIENTLY FOR NEW CONVECTION TO DEVELOP LATER THIS AFTERNOON AND EVENING. VERY UNSTABLE CONDITIONS IMMEDIATELY SOUTH OF THE OUTFLOW BOUNDARY WITH MLCAPE EXCEEDING 4000 J/KG COUPLED WITH STRONG DEEP LAYER SHEAR/LOW LEVEL HELICITY INDICATE A FAVORABLE ENVIRONMENT FOR SUPERCELL THUNDERSTORMS CAPABLE OF PRODUCING VERY LARGE HAIL...DAMAGING WIND GUSTS...AND A FEW TORNADOES /PRIMARILY ALONG AND JUST NORTH OF THE OUTFLOW BOUNDARY/. SEVERE CONVECTION IS FORECAST TO GROW UPSCALE INTO ANOTHER MCS LATER THIS EVENING AND TRACK ESEWD ALONG THE OUTFLOW BOUNDARY ACROSS THE MIDDLE MS VALLEY...WITH A CONTINUED THREAT FOR DAMAGING WIND GUSTS AND LARGE HAIL THROUGH THE OVERNIGHT HOURS. ...UPPER MS VALLEY INTO THE UPPER GREAT LAKES... ALTHOUGH THE CIRRUS CANOPY ASSOCIATED WITH THE IA/IL MCS EXTENDS NWD INTO SRN MN AND WI...LATEST VISIBLE IMAGERY SHOWS THINNING CLOUDS NEAR THE FRONT OVER EAST CENTRAL MN AND FAR NWRN WI. THIS MAY PERMIT ENHANCED HEATING AND AIR MASS DESTABILIZATION TO OCCUR...INCREASING THE POTENTIAL FOR ADDITIONAL STRONG/SEVERE STORMS TO DEVELOP ALONG/AHEAD OF THE ADVANCING COLD FRONT. A 50-60 KT MID LEVEL JET STREAK MOVING EWD ACROSS THIS AREA IN ASSOCIATION WITH THE SHORT WAVE TROUGH WILL INCREASE THE DYNAMIC FORCING FOR LARGE SCALE ASCENT AND CONTRIBUTE TO STRONG DEEP LAYER SHEAR. ALTHOUGH THE ENVIRONMENT IS LESS UNSTABLE COMPARED TO REGIONS FARTHER SOUTH...THERE WILL CONTINUE TO BE A THREAT FOR SEVERE THUNDERSTORMS SPREADING EWD ACROSS THIS REGION LATER THIS AFTERNOON INTO TONIGHT. ...UPPER TN VALLEY INTO THE GULF COAST REGION... SCATTERED THUNDERSTORMS HAVE DEVELOPED FROM NRN AL SWD INTO PARTS OF SWRN GA/SRN AL AND CENTRAL/SRN MS. THIS ACTIVITY IS WITHIN A THERMODYNAMIC ENVIRONMENT CHARACTERIZED BY AMPLE MOISTURE AND STEEP LAPSE RATES IN THE LOWEST 1-2 KM...WITH DRY AIR AND MODERATELY STEEP LAPSE RATES ALOFT. 20-25 KT NELY MID LEVEL WINDS WILL SUPPORT MODEST CONVECTIVE ORGANIZATION AND HELP MAINTAIN A THREAT FOR WET MICROBURSTS AND POSSIBLE HAIL WITH STRONGER CELLS. ...SRN APPALACHIANS NWD INTO PARTS OF VA... 18Z GSO AND RNK RAOBS EXHIBIT VERY STEEP LOW LEVEL LAPSE RATES AND LARGE SURFACE TEMPERATURE/DEW POINT SPREADS...WHICH WILL ENHANCE DOWNDRAFT STRENGTH. WEAK WINDS ALOFT AND MINIMAL VERTICAL SHEAR INDICATES LIKELIHOOD OF PULSE STORMS WITH ATTENDANT POTENTIAL FOR BRIEF MICROBURSTS. THIS CONVECTION SHOULD WEAKEN AFTER SUNSET. ..WEISS.. 07/19/2006  From swody1 at goshenarc.org Thu Jul 20 01:12:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 19 Jul 2006 21:12:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200109 SWODY1 SPC AC 200108 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0808 PM CDT WED JUL 19 2006 VALID 200100Z - 201200Z ...THERE IS A MDT RISK OF SVR TSTMS OVER A PORTION OF THE UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MIDDLE AND UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER WRN LA THROUGH NERN TX... ...IA THROUGH SRN MN AND SRN THROUGH CNTRL WI... SURFACE OBSERVATIONS SHOW A COLD FRONT FROM A WEAK SURFACE LOW IN NERN NEB SWWD THROUGH CNTRL AND SWRN NEB. THIS BOUNDARY CONTINUES NEWD FROM THE LOW THROUGH CNTRL AND NRN MN. FARTHER S AN OUTFLOW BOUNDARY EXTENDS FROM SRN IL NWWD THROUGH NERN MO INTO W CNTRL AND NWRN IA WHERE IT INTERSECTS THE FRONT. THE ATMOSPHERE REMAINS EXTREMELY UNSTABLE IN THE PRE-FRONTAL WARM SECTOR ACROSS MUCH OF IA WITH MLCAPE FROM 4000 TO 5000 J/KG. WITH THE EXCEPTION OF HIGH BASED STORMS DEVELOPING WITHIN THE MORE DEEPLY MIXED PLUME JUST AHEAD OF THE FRONT ACROSS NEB...SURFACE BASED INITIATION HAS YET TO OCCUR. LACK OF CUMULUS WITHIN THE WARM SECTOR ACROSS IA SUGGESTS THE BOUNDARY LAYER IS STILL CAPPED AND THIS LENDS UNCERTAINTY AS TO WHEN THE STRONGER STORMS WILL INITIATE. THE MODERATE RISK THEREFORE REMAINS CONDITIONAL. SWLY LOW LEVEL JET WILL STRENGTHEN THIS EVENING OVER THE UPPER MS VALLEY AS NRN STREAM SHORTWAVE TROUGH MOVES ESEWD THROUGH SRN CANADA AND NRN MN. THIS SUGGEST THAT STORMS WILL INCREASE N OF THE OUTFLOW BOUNDARY WITHIN ZONE OF ISENTROPIC ASCENT FROM NRN IA INTO SERN MN AND SRN WI. MANY OF THESE STORMS MAY INITIALLY BE ELEVATED WITH A THREAT FOR MAINLY LARGE HAIL. HOWEVER...THE 00Z DAVENPORT RAOB SHOWS THE BOUNDARY LAYER TO BE SUFFICIENTLY DRY AND WARM TO SUPPORT A THREAT OF DAMAGING WIND...ESPECIALLY IF STORMS BEGIN TO CONGEAL INTO AN MCS AND IF STORMS CAN DEVELOP CLOSER TO THE STRONGER SURFACE BASED INSTABILITY ACROSS IA. GIVEN THE MAGNITUDE OF INSTABILITY AND SUFFICIENT VERTICAL SHEAR FOR SUPERCELL STRUCTURES...A FEW STORMS COULD PRODUCE VERY LARGE HAIL...ESPECIALLY IN THE MODERATE RISK AREA. TORNADO THREAT REMAINS CONDITIONAL UPON BEING ABLE TO INITIATE STORMS CLOSER TO THE OUTFLOW BOUNDARY ACROSS PARTS OF NRN AND CNTRL IA. ...SRN IL THROUGH E CNTRL AND SERN MO... THREAT FOR MAINLY DAMAGING WIND IS EXPECTED TO PERSIST FOR ANOTHER FEW HOURS AS MCS CONTINUES SWD INTO PARTS OF SERN MO. THIS ACTIVITY IS EXPECTED TO BEGIN AN OVERALL DECREASING TREND AS THE BOUNDARY LAYER BEGINS TO STABILIZE LATER THIS EVENING. ...LA THROUGH ERN TX... MCS WILL CONTINUE WSWWD INTO NERN TX NEXT FEW HOURS...BEFORE BEGINNING AN OVERALL DECREASING TREND LATER THIS EVENING AS THE BOUNDARY LAYER BEGINS TO STABILIZE. DAMAGING WIND WILL BE THE PRIMARY THREAT WITH THIS ACTIVITY. ..DIAL.. 07/20/2006  From swody1 at goshenarc.org Thu Jul 20 06:00:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 20 Jul 2006 02:00:21 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 200557 SWODY1 SPC AC 200555 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT THU JUL 20 2006 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MID MS VALLEY...OH VALLEY THROUGH GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CNTRL AND NRN PLAINS... ...SYNOPSIS... UPPER PATTERN WILL REMAIN DOMINATED BY STRONGER WLYS FROM THE NRN ROCKIES THROUGH THE GREAT LAKES AREA. AN UPPER RIDGE WILL PERSIST OVER THE SRN TWO THIRDS OF THE COUNTRY. EMBEDDED WITHIN THE STRONGER WLYS AN UPPER TROUGH WILL CONTINUE EWD THROUGH SERN CANADA AND THE GREAT LAKES. FARTHER W...THE SHORTWAVE TROUGH CURRENTLY MOVING INTO THE NRN ROCKIES WILL BEGIN TO AMPLIFY SEWD INTO THE NRN HIGH PLAINS BY THURSDAY EVENING AS IT CRESTS THE UPPER RIDGE. A COLD FRONT WILL CONTINUE EWD THROUGH THE GREAT LAKES REGION IN ASSOCIATION WITH THE NRN STREAM UPPER TROUGH. THIS BOUNDARY WILL EXTEND SWWD INTO THE CNTRL PLAINS WHERE IT WILL BEGIN TO STALL. A SECONDARY FRONTAL SURGE WILL ACCOMPANY THE SHORTWAVE TROUGH SEWD INTO THE NRN HIGH PLAINS BY THURSDAY EVENING. ...MID MS VALLEY THROUGH THE OH VALLEY AND GREAT LAKES AREA... STEEP LAPSE RATES HAVE SPREAD EWD FROM THE PLAINS ABOVE HIGHER THETA-E AIR OVER THE MID MS VALLEY...RESULTING IN A RESERVOIR OF STRONG INSTABILITY THAT WILL PERSIST INTO THURSDAY. MLCAPE IS EXPECTED TO RANGE FROM 3500+ J/KG OVER PARTS OF THE MID MS VALLEY TO AROUND 1500 J/KG OR LESS OVER THE OH VALLEY AND GREAT LAKES REGION WHERE LAPSE RATES AND LOW LEVEL MOISTURE WILL BE MORE LIMITED. COMPLICATING FACTOR FOR THIS OUTLOOK WILL BE POTENTIAL FOR ONGOING STORMS EARLY IN THE PERIOD. ACTIVITY NOW OVER PARTS OF NERN IA AND SRN WI MAY CONTINUE SEWD INTO N CNTRL IL BY THE START OF THE PERIOD. THE LOW LEVEL JET IS FORECAST TO WEAKEN DURING THE DAY WITH LARGELY UNIDIRECTIONAL DEEP LAYER FLOW. AROUND 35-40 KT WLY 6 KM FLOW ACCOMPANYING THE UPPER TROUGH WILL CONTRIBUTE TO DEEP LAYER SHEAR SUFFICIENT FOR SOME ORGANIZED STORM STRUCTURES. HOWEVER...THE STRONGER FLOW IS EXPECTED TO REMAIN N OF THE BETTER INSTABILITY. CURRENT THINKING IS THAT ONGOING STORMS MAY RE-INTENSIFY AS THE DOWNSTREAM ATMOSPHERE DESTABILIZES. OTHER STORMS MAY DEVELOP IN ASSOCIATION WITH REMNANT OUTFLOW BOUNDARIES AND SPREAD EWD INTO THE OH VALLEY. PRIMARY THREATS WILL BE DAMAGING WIND AND HAIL. OTHER STORMS MAY DEVELOP FARTHER NE ALONG FRONT FROM THE GREAT LAKES INTO SRN CANADA. THIS ACTIVITY MAY REACH PARTS OF THE NERN U.S. OVERNIGHT WITH A THREAT OF ISOLATED DAMAGING WIND GUSTS. ....NRN HIGH PLAINS THROUGH CNTRL PLAINS... ESELY UPSLOPE COMPONENT ALONG SRN PERIPHERY OF SURFACE RIDGE WILL MAINTAIN BOUNDARY LAYER DEWPOINTS IN THE 50S OVER PARTS OF THE CNTRL AND NRN HIGH PLAINS. STEEP LAPSE RATES ABOVE THIS MOIST AXIS WILL CONTRIBUTE TO MODERATE INSTABILITY DURING THE AFTERNOON. STORMS WILL LIKELY DEVELOP INITIALLY OVER THE HIGHER TERRAIN AND THEN SPREAD SEWD INTO THE MOIST AXIS WHERE MODERATE INSTABILITY WILL EXIST. A BELT OF STRONGER 40 KT MID LEVEL FLOW ACCOMPANYING THE UPPER TROUGH WILL SPREAD SEWD ABOVE THE SELY LOW LEVEL FLOW CONTRIBUTING TO SUFFICIENT SHEAR FOR SUPERCELLS. OTHER STORMS MAY DEVELOP N OF THE SURFACE FRONT DURING THE EVENING AS THE LOW LEVEL JET STRENGTHENS WITH STORMS EVENTUALLY EVOLVING INTO ONE OR MORE MCSS. LARGE HAIL AND DAMAGING WIND WILL BE THE MAIN THREATS. ...SRN AZ... ELY FLOW ON SRN PERIPHERY OF UPPER RIDGE SUGGESTS STORMS THAT DEVELOP OVER THE RIM AND OVER THE HIGHER TERRAIN OF SERN AZ AND SWRN NM WILL HAVE POTENTIAL TO SPREAD INTO THE DESERT VALLEYS. TEMPERATURE/DEWPOINT SPREADS WILL BE SUFFICIENT FOR A THREAT OF MICROBURSTS. HOWEVER...COVERAGE IS EXPECTED TO REMAIN TOO ISOLATED FOR A SLIGHT RISK. ..DIAL/TAYLOR.. 07/20/2006  From swody1 at goshenarc.org Thu Jul 20 12:48:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 20 Jul 2006 08:48:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201240 SWODY1 SPC AC 201239 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0739 AM CDT THU JUL 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID MS/OH AND TN VALLEYS AND GREAT LAKES AREA... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN HIGH PLAINS SEWD INTO CENTRAL PLAINS... ...SYNOPSIS... A TROUGH WILL BEGIN TO DEEPEN FROM THE NRN/CENTRAL ROCKIES EWD INTO THE NRN OHIO VALLEY AND NEW ENGLAND AS THE LARGE UPPER RIDGE SHIFTS WWD AND BEGINS TO BUILD NWD INTO THE PACIFIC NW. EMBEDDED WITHIN THIS AMPLIFYING TROUGH WILL BE ONE SHORTWAVE TROUGH MOVING THROUGH THE GREAT LAKES AND ANOTHER DROPPING SEWD FROM THE NRN ROCKIES INTO THE CENTRAL PLAINS. A COLD FRONT ASSOCIATED WITH THE DEEPENING TROUGH WILL MOVE EWD AND IS FORECAST TO EXTEND FROM THE EASTERN GREAT LAKES SWWD INTO MO AND THEN WWD INTO ERN CO BY LATE AFTERNOON. ...MID MS/OH/TN VALLEYS AND GREAT LAKES AREA... CONVECTIVE EVOLUTION AND SEVERE THREAT TODAY COMPLICATED BY ONGOING CONVECTION...BUT LARGE AREA OF INSTABILITY AND UNSEASONABLY HOT TEMPERATURES WITHIN A MOIST BOUNDARY LAYER WILL RESULT IN A LARGE SLIGHT RISK AREA. CURRENT THINKING IS WEAKENED BOW ECHO IN NRN IL/IND WILL MOVE SWD DURING THE DAY IN RESPONSE TO WLY LOW LEVEL JET AND INSTABILITY AXIS THAT CURRENTLY EXTENDS SWD FROM THE SYSTEM. WELL ORGANIZED COLD POOL/MESO HIGH SHOULD KEEP SYSTEM ORGANIZED UNTIL THE AIR MASS DESTABILIZES SUFFICIENTLY FOR REINTENSIFICATION OF THE SYSTEM. ALTHOUGH THE MID LEVEL WINDS/DEEP LAYER SHEAR WILL BE WEAKER ACROSS THE LOWER OH/TN VALLEY THAN ACROSS THE GREAT LAKES AREA...STRONG INSTABILITY...STEEP LAPSE RATES AND ORGANIZED OUTFLOW LIKELY WOULD KEEP THIS SYSTEM SEVERE AT LEAST AS FAR SOUTH AS TN. OTHER SEVERE STORMS MAY DEVELOP ALONG FRONT/OUTFLOW BOUNDARIES THIS AFTERNOON AND EVENING DUE TO STRONG INSTABILITY...MLCAPES RANGING FROM 3500+ J/KG MID MS VALLEY TO AROUND 1500 J/KG OVER THE OH VALLEY...AND STRENGTHENING WINDS ALOFT/SHEAR AS HEIGHTS SLOWLY FALL. GIVEN THE WARM MID LEVEL TEMPERATURES ALOFT...THE PRIMARY THREAT WILL BE DAMAGING WINDS. ....NRN/CENTRAL HIGH PLAINS... ESELY BOUNDARY LAYER WINDS BEHIND COLD FRONT WILL MAINTAIN DEWPOINTS IN THE 50S OVER PARTS OF THE CNTRL/NRN HIGH PLAINS. STEEP LAPSE RATES ABOVE THE MOIST AXIS WILL CONTRIBUTE TO MODERATE INSTABILITY THIS AFTERNOON. AS SHORTWAVE TROUGH MOVES SEWD INTO THE AREA...STORMS ARE EXPECTED TO DEVELOP OVER THE HIGHER TERRAIN. THOUGH THE WINDS ARE NOT FORECAST TO BE PARTICULARLY STRONG BELOW 500 MB...SELY BOUNDARY LAYER WINDS VEERING TO WLY IN THE LOWER 3KM WILL RESULT IN SUFFICIENT SHEAR FOR SUPERCELLS. AN ISOLATED TORNADO OR TWO MAY BE POSSIBLE WHEN THE STORMS FIRST DEVELOP...BUT AS OUTFLOWS MERGE...STORMS SHOULD ORGANIZE INTO AN MCS AND MOVE SEWD ALONG THE 850 MB TEMPERATURE GRADIENT AND INTO THE 25 KT LOW LEVEL JET. SEVERE HAIL WOULD BE THE PRIMARY THREAT EARLY AND THEN TRANSITION INTO MORE OF A DAMAGING WIND THREAT AS THE SYSTEM FORWARD PROPAGATES INTO WRN/CENTRAL NEB AND NRN KS. ...SWRN TX... UPPER WAVE THAT RESULTED IN SEVERE THUNDERSTORMS FROM AL INTO ERN TX WED WILL BE MOVING ACROSS SWRN TX DURING THE PERIOD OF MAX HEATING. ALTHOUGH THE BOUNDARY LAYER WILL NOT BE AS MOIST OR UNSTABLE AS IT WAS ACROSS THE CENTRAL GULF STATES... INVERTED-V SOUNDINGS SUGGEST STRONG/BRIEF SEVERE WIND GUSTS ARE POSSIBLE WITH STORMS. ...SRN AZ... ELY WINDS ARE FORECAST THROUGHOUT MUCH OF THE TROPOSPHERE ACROSS AZ TODAY. HOWEVER...WATER VAPOR IMAGERY SHOWS DRIER AIR SPREADING IN FROM NEW MEXICO AND THE CONVECTIVE COVERAGE WAS MOSTLY SUPPRESSED WITHIN THIS DRIER MID/HIGH LEVEL AIR MASS ON WED. STORMS CURRENTLY OVER SERN AZ SHOULD SHIFT WWD...BUT MORNING CLOUDS/PCPN SHOULD LIMIT HEATING/INSTABILITY SOMEWHAT. AS DRIER AIR MOVES IN FROM THE EAST...ONLY ISOLATED STORMS ARE EXPECTED OVER THE HIGHER TERRAIN OF SERN AZ THIS AFTERNOON. ..IMY.. 07/20/2006  From swody1 at goshenarc.org Sat Jul 22 05:57:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 01:57:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220554 SWODY1 SPC AC 220552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1252 AM CDT SAT JUL 22 2006 VALID 221200Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE NERN STATES THROUGH THE MID ATLANTIC...SERN STATES...LOWER MS VALLEY AND SERN TX... ...SYNOPSIS... SYNOPTIC PATTERN WILL REMAIN DOMINATED BY AN UPPER TROUGH OVER THE OH VALLEY AND GREAT LAKES WITH A CLOSED UPPER RIDGE IN THE W. SERIES OF VORTICITY MAXIMA WILL ROTATE THROUGH THE UPPER TROUGH. ONE SUCH FEATURE NOW MOVING THROUGH THE BASE OF THE TROUGH AND INTO THE OH VALLEY WILL CONTINUE ENEWD INTO THE NERN STATES SATURDAY AFTERNOON. A SURFACE LOW WILL ACCOMPANY THE VORT MAX AND IS FORECAST TO UNDERGO SOME DEEPENING AS IT TRACKS NEWD ALONG THE SURFACE FRONT INTO PA BY AFTERNOON. NERN PORTION OF THIS FRONT WILL MOVE VERY LITTLE OR LIFT SLOWLY NWD...WHILE THE SWRN PORTIONS WILL CONTINUE SWD THROUGH THE SERN STATES AND S TX. ...MID ATLANTIC THROUGH SRN NEW ENGLAND... RICH LOW LEVEL MOISTURE EXISTS IN THE PRE-FRONTAL WARM SECTOR WITH DEWPOINTS IN THE LOWER 70S. PRIMARY CONCERN IS HOW SEVERAL MCSS NOW ONGOING FROM THE CNTRL APPALACHIANS WWD INTO THE OH VALLEY WILL EVOLVE. COLD POOL FROM MCS NOW ONGOING FROM WV SWD THROUGH WRN NC WAS APPARENTLY DEEP AND STRONG ENOUGH TO CROSS THE MOUNTAINS WITH NEW STORMS CONTINUING TO DEVELOP ALONG THE LEADING OUTFLOW. MUCH OF THE ATMOSPHERE IN THIS REGION HAS NOT BEEN OVERTURNED AND THERE IS CONCERN THAT STORMS MAY CONTINUE DEVELOPING INTO MUCH OF THE NIGHT...ESPECIALLY FROM VA SWD. MUCH OF THIS CONVECTION SHOULD REMAIN S OF THE MID ATLANTIC AND NERN STATES...BUT DEBRIS FROM UPSTREAM STORMS CURRENTLY OVER THE OH VALLEY COULD ALSO SERVE TO LIMIT HEATING AND INSTABILITY. WHERE POCKETS OF SURFACE HEATING DO DEVELOP...MLCAPE FROM 1000 TO 1500 J/KG WILL BE POSSIBLE GIVEN THE RICH LOW LEVEL MOISTURE IN PLACE. LOW LEVEL JET WILL STRENGTHEN WITHIN ZONE OF ASCENT AND HEIGHT FALLS E OF SURFACE LOW FROM NRN VA THROUGH ERN PA AND SRN NEW ENGLAND AS THE SHORTWAVE TROUGH ADVANCES EWD DURING THE DAY. THE STRENGTHENING LOW LEVEL WIND FIELDS AND MID LEVEL JET ACCOMPANYING THE SHORTWAVE TROUGH WILL CONTRIBUTE TO FAVORABLE KINEMATIC PROFILES FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND BOW ECHOES. LOW LEVEL STORM RELATIVE HELICITY FROM 200 TO 300 M2/S2 WILL POSE A THREAT FOR LOW LEVEL MESOCYCLONES AND TORNADOES WITH ANY DISCRETE STORM STRUCTURES. OTHERWISE DAMAGING WIND WILL BE POSSIBLE. HIGHER END SEVERE THREAT IS CONDITIONAL ON DEGREE OF INSTABILITY AND HOW MUCH ONGOING CONVECTION CONTAMINATES THE WARM SECTOR. WILL KEEP THIS AREA IN SLIGHT RISK FOR NOW DUE TO THE POTENTIAL LIMITING FACTOR. HOWEVER...AN UPGRADE TO MODERATE RISK MIGHT BE NEEDED IN LATER OUTLOOKS ONCE IT BECOMES CLEAR IF AND WHERE SUFFICIENT DESTABILIZATION WILL OCCUR. ...CAROLINAS THROUGH THE SERN STATES AND SERN TX... POSSIBILITY REMAINS THAT MCS NOW CROSSING THE APPALACHIANS WILL CONTINUE INTO THE MORNING...EXHAUSTING MUCH OF THE INSTABILITY AND REDUCING THE SEVERE THREAT OVER THE CAROLINAS. WILL LEAVE A SLIGHT RISK FOR NOW IN CASE THIS SCENARIO DOES NOT PLAY OUT AND THE ATMOSPHERE IS ABLE TO RECOVER. WEAK VERTICAL WIND PROFILES WILL SUPPORT MULTICELL STORMS IN PRE-FRONTAL WARM SECTOR WITH A THREAT FOR MAINLY ISOLATED DAMAGING WIND. FARTHER SW FROM GA THROUGH THE LOWER MS VALLEY AND S TX...MORE ABUNDANT SURFACE HEATING SHOULD ALLOW THE ATMOSPHERE TO BECOME MODERATELY UNSTABLE. SCATTERED MULTICELL STORMS WILL LIKELY INTENSIFY ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON WITH A THREAT FOR ISOLATED DAMAGING WIND GUSTS THROUGH MID EVENING. ...WI... A SHORTWAVE TROUGH WILL DROP SWD INTO THE UPPER MS VALLEY AND WRN GREAT LAKES AREA DURING THE DAY. RELATIVELY COOL MID LEVEL TEMPERATURES (-12C AT 500 MB) AND STRONG SURFACE HEATING WILL CONTRIBUTE TO STEEP LAPSE RATES AND MLCAPE AROUND 1000 J/KG. AS THE ATMOSPHERE DESTABILIZES...STORMS WILL LIKELY DEVELOP DURING THE AFTERNOON WITHIN ZONE OF ASCENT ASSOCIATED WITH THE SERN MOVING IMPULSE. THE THERMODYNAMIC ENVIRONMENT SUGGEST A FEW STORMS COULD PRODUCE GUSTY WINDS AND HAIL THROUGH EARLY EVENING. ..DIAL/CROSBY.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 12:37:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 08:37:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221233 SWODY1 SPC AC 221231 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0731 AM CDT SAT JUL 22 2006 VALID 221300Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NORTHERN AL/GA...ACROSS THE MID ATLANTIC REGION...INTO SOUTHERN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF MN/IA... MORNING SATELLITE LOOPS SHOW WELL-DEFINED UPPER TROUGH ROTATING THROUGH THE OH VALLEY. THIS SYSTEM WILL BRING RATHER STRONG WIND FIELDS AND LIFT TO MUCH OF THE NORTHEAST AND MID ATLANTIC STATES TODAY...ALONG WITH A RISK OF SEVERE THUNDERSTORMS WHERE DAYTIME HEATING CAN OCCUR. ...SOUTHERN NEW ENGLAND INTO PA/NJ... SURFACE LOW NOW OVER NORTHWESTERN PA IS FORECAST TO DEEPEN AND TRACK EASTWARD ACROSS PA/NY AND INTO WESTERN NEW ENGLAND TODAY. A VERY MOIST AIR MASS WILL BE PRESENT IN WARM SECTOR OF LOW WITH DEWPOINTS IN THE 70S...BUT ALSO WITH SCATTERED CLOUD COVER AND SHOWERS. MODEL FORECAST SOUNDINGS FROM EASTERN PA/NJ NORTHWARD ACROSS SOUTHERN NEW ENGLAND SUGGEST UNSEASONABLY STRONG LOW/MID LEVEL WIND FIELDS WILL DEVELOP BY AFTERNOON /6KM SHEAR OF 35-45 KNOTS AND 0-3KM HELICITY OF 150-250 M2/S2/...FAVORABLE FOR SUPERCELL STORMS AND EVEN ISOLATED TORNADOES. HOWEVER...LACK OF STRONG HEATING WILL LIKELY MITIGATE OVERALL SEVERE THREAT ACROSS THIS REGION. PRESENT INDICATIONS ARE THAT ONGOING THUNDERSTORM ACTIVITY OVER PA/NY WILL PROGRESS EASTWARD...WITH SOME INTENSIFICATION POSSIBLE ALONG THE SOUTHEAST FRINGE OF STORMS ACROSS EASTERN PA/NJ AND SOUTHEAST NY. THESE STORMS WILL MOVE NORTHEASTWARD INTO SOUTHERN NEW ENGLAND BY LATE AFTERNOON. SURFACE TEMPERATURES IN THE LOWER 80S WILL BE SUFFICIENT FOR SURFACE-BASED STORMS AND A RISK OF SUPERCELLS. NORTHWARD EXTENT OF SEVERE THREAT WILL BE DICTATED BY CLOUD COVER AND ASSOCIATED SURFACE HEATING. DAMAGING WINDS AND ISOLATED TORNADOES APPEAR TO BE THE MAIN THREATS IN THIS REGION. ...MID ATLANTIC REGION... MORNING SHOWERS ARE EXPECTED TO DISSIPATE SOMEWHAT BY EARLY AFTERNOON...ALLOWING MODERATE DAYTIME HEATING FROM NORTHERN NC INTO MD/DE. SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER THE MOUNTAINS OF WESTERN NC/VA AND MOVE EASTWARD THIS AFTERNOON. SUFFICIENT WIND FIELDS ALOFT AND MODERATE INSTABILITY WILL PROMOTE A RISK OF DAMAGING WINDS IN STRONGER CELLS. ...CAROLINA COAST... STRONG HEATING OVER COASTAL NC/SC WILL ALLOW SEA BREEZE TO MOVE ONSHORE LATER THIS AFTERNOON. INTERACTION OF SEA BREEZE WITH CONVECTIVE OUTFLOWS FROM OVERNIGHT AND AFTERNOON THUNDERSTORMS MAY RESULT IN ISOLATED SEVERE STORMS CAPABLE OF DAMAGING WINDS. THREAT SHOULD DIMINISH RAPIDLY AFTER SUNSET. ...MN/IA... RELATIVELY STRONG NORTHWEST FLOW PATTERN WILL BE PRESENT TODAY OVER THE MIDWEST. FULL SUNSHINE AND STEEP LAPSE RATES WILL ALLOW AIRMASS TO BECOME MODERATELY UNSTABLE BY LATE AFTERNOON...DESPITE SURFACE DEWPOINTS ONLY IN THE LOW 60S. PRESENT INDICATIONS ARE THAT ISOLATED THUNDERSTORMS WILL DEVELOP OVER SOUTHEAST MN BY LATE AFTERNOON...SPREADING SOUTHWARD INTO IA DURING THE EVENING. BRIEF SUPERCELLS ARE POSSIBLE WITH A RISK OF HAIL AND GUSTY WINDS. ..HART/CROSBIE.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 16:43:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 12:43:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221640 SWODY1 SPC AC 221638 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1138 AM CDT SAT JUL 22 2006 VALID 221630Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND TO MID ATLANTIC STATES... ...THERE IS A SLGT RISK OF SVR TSTMS PARTS OF UPPER MISSISSIPPI VALLEY... ...NERN U.S... SEASONABLY DEEP UPPER TROUGH ERN U.S. WITH VERY LARGE UPPER HIGH IN THE WEST. THE S/WV TROUGH DEPICTED ON W/V IMAGERY AND HEIGHT FALLS AT 12Z IS LIFTING NEWD ACROSS NY/PA ATTM WITH ASSOCIATED BAND OF STRONGER WIND FIELDS SPREADING ACROSS NERN U.S. AHEAD OF S/WV THIS AFTERNOON AND EVENING. SURFACE LOW AT 15Z NERN PA IS GRADUALLY DEEPENING AS IT TRACKS NEWD TO SERN NY LATER THIS AFTERNOON AND NRN VT/NH LATER TONIGHT. A VERY WARM AND MOIST AIRMASS IS SPREADING NEWD IN THE 30-35KT SWLY FLOW AHEAD OF LOW AND THE WEAK COLD FRONT WHICH TRAILS SWWD TO NRN GULF STATES. SHEAR PROFILES ARE IN PLACE TO SUPPORT SEVERE THUNDERSTORMS AND SUPERCELLS AHEAD OF SURFACE LOW FROM ERN DELMARVA NEWD INTO SRN NEW ENGLAND THIS AFTERNOON AND EVENING. THE PRIMARY CAVEAT IS SURFACE HEATING AS EXTENSIVE CLOUDINESS THIS AM IS ONLY SLOWLY THINNING. HOWEVER WITH ONLY WEAK CIN...AND HEATING NOW SHOWING E OF APPALACHIANS AS FAR N AS SRN PA...TEMPERATURES SHOULD RISE THRU THE 80S NWD THRU SERN NY BY MID AFTERNOON. THIS WILL RESULT IN MLCAPES INCREASING TO NEAR 2000 J/KG AS FAR N AS NJ/ERN NY AND 1000-1500 J/KG SRN NEW ENGLAND LATE THIS AFTERNOON. SURFACE BASED STRONG/SEVERE THUNDERSTORMS WILL DEVELOP BY 18Z AHEAD OF SURFACE LOW AND ALONG LEE TROUGH LOCATED TO E OF APPALACHIANS. PRIMARY THREAT WILL BE DAMAGING WINDS AS STORMS FORM INTO CLUSTERS AND LINES...HOWEVER 20-25KT OF SFC-1KM SHEAR AND LOW LCLS ALSO SUPPORT SUPERCELLS. GREATEST TORNADIC SUPERCELL POTENTIAL WOULD BE IN ENHANCED LOW LEVEL CONVERGENCE AHEAD OF LOW AND VICINITY THE SUBTLE WARM FRONT EXTENDING EWD THRU SRN NEW ENGLAND AND ALONG THE SURFACE LEE TROUGH THAT WILL BE LOCATED VICINITY PA/NJ BORDER LATER THIS AFTERNOON. ...MID ATLANTIC/GULF COAST STATES... WHILE SHEAR WILL BE WEAKER ACROSS THIS AREA...THE AIR MASS IS VERY MOIST AND POTENTIALLY QUITE UNSTABLE. GOOD HEATING UNDERWAY MUCH OF THE REGION AHEAD OF COLD FRONT WHICH HAS PROGRESSED TO NRN AL AND MS. THUNDERSTORMS WILL BE COMMON ALONG AND AHEAD OF COLD FRONT BY MID AFTERNOON AS MLCAPES CLIMB TO 2000 J/KG OR MORE. WITH DEEP LAYER SHEAR GENERALLY LESS THAN 20KT...STORM MODE SHOULD BE PULSE/MULTICELL. PRIMARY SEVERE THREAT WILL BE WET MICRO-BURSTS. SEVERE OCCURRENCE SHOULD BE GREATEST CAROLINAS WHERE SHEAR IS GREATER...DECREASING TO MORE ISOLATED COVERAGE GULF STATES. ...UPPER MS VALLEY... WEAK IMPULSE EMBEDDED IN NLY FLOW NOTED ON W/V IMAGERY DROPPING SWD THRU WI TODAY. OVERALL THE SHEAR OF 30KT OR LESS SUPPORT MULTICELL CONVECTIVE MODE. WITH FREEZING LEVELS NEAR 10K FT AND AFTERNOON HEATING GENERATING SBCAPE TO 1000-1500 J/KG A FEW SEVERE THUNDERSTORMS ARE LIKELY. PRIMARY THREAT WILL BE LARGE HAIL WITH THE EARLIER SLIGHT RISK AREA BEING SHIFTED EWD INTO WI WHERE TRACK OF UPPER SYSTEM IS LOCATED. ...SWRN U.S... VERY TO EXTREMELY HOT CONDITIONS CONTINUE UNDER LARGE UPPER HIGH. MOISTURE HAS CONTINUED TO INCREASE NWWD THRU W COAST STATES WITH PW/S GENERALLY 1.25 TO 1.5 NOTED. WITH VERY STEEP LAPSE RATES...THUNDERSTORMS WILL DEVELOP OVER HIGHER TERRAIN FROM NM/AZ NWWD THRU INTERIOR CA/WRN NV. ISOLATED SEVERE DOWNBURSTS ARE LIKELY AS STORMS DRIFT OFF MOUNTAINS LATER THIS AFTERNOON WITH MARGINALLY SEVERE HAIL ALSO POSSIBLE PRIMARILY OVER HIGHER TERRAIN. ..HALES/GRAMS.. 07/22/2006  From swody1 at goshenarc.org Sat Jul 22 19:52:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 15:52:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221949 SWODY1 SPC AC 221947 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0247 PM CDT SAT JUL 22 2006 VALID 222000Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND SWD ALONG THE ATLANTIC COAST AND WWD ALONG THE GULF COAST... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPPER MIDWEST... ...SRN NEW ENGLAND INTO THE CAROLINAS... AFTERNOON WATER VAPOR IMAGERY SHOWS VIGOROUS SHORT WAVE TROUGH LIFTING NEWD THROUGH THE LOWER GREAT LAKES WITH AN ACCOMPANYING BELT OF 35-45 KT SWLY MID-LEVEL FLOW FROM THE CNTRL APPALACHIANS INTO NEW ENGLAND. ATTENDANT SURFACE LOW OVER THE LOWER HUDSON VALLEY IS FORECAST TO CONTINUE NEWD THROUGH THE REMAINDER OF THE AFTERNOON AND TONIGHT WITH TRAILING COLD FRONT PUSHING TOWARD THE MIDDLE ATLANTIC COAST. THUS FAR...STRONGEST TSTM DEVELOPMENT HAS OCCURRED ALONG LEE TROUGH FROM VICINITY OF SURFACE LOW OVER SERN NY SWWD INTO CNTRL/ERN MD WHERE BREAKS IN THE CLOUDS HAVE ALLOWED FOR STRONGER DAYTIME HEATING. THIS ISOLATION COUPLED WITH DEWPOINTS OF 70-75 F ARE CONTRIBUTING TO MLCAPES OF 500-1500 J/KG. CURRENTLY...REGIONAL VWPS INDICATE THAT STRONGEST LOW AND DEEP-LAYER SHEAR /150-250 M2/S2 0-1 KM SRH AND 35-45 KTS OF 0-6 KM SHEAR/ EXISTS FROM NRN/CNTRL NJ NWD INTO THE SRN NEW ENGLAND AND THE MIDDLE HUDSON VALLEY...WHERE STRONGEST ISALLOBARIC RESPONSE IS OCCURRING E OF SURFACE LOW. HOWEVER...18Z ALBANY AND UPTON NY SOUNDINGS INDICATE THAT CONSIDERABLE CLOUDS AND PRECIPITATION HAVE LIMITED DESTABILIZATION WITHIN THIS REGION OF STRONGER SHEAR. EXPECT GREATEST SEVERE THREAT TO EXIST FROM SERN NY/NJ SSWWD INTO CHESAPEAKE BAY THIS AFTERNOON AND EVENING...WHERE BEST COMBINATION OF INSTABILITY AND STRONGER VERTICAL SHEAR WILL BE CO-LOCATED. HERE...POTENTIAL WILL EXIST FOR SMALL-SCALE BOWING STRUCTURES AND PERHAPS A SUPERCELL OR TWO CAPABLE OF MAINLY DAMAGING WINDS. GREATEST THREAT OF A TORNADO WILL LIKELY EXIST OVER SERN NY INTO SWRN NEW ENGLAND...SHOULD SUFFICIENT DESTABILIZATION OCCUR TO SUSTAIN DEEP CONVECTION. FARTHER S INTO THE CAROLINAS...VERTICAL SHEAR DECREASES WITH SWD EXTENT...THOUGH AIR MASS REMAINS HOT AND MOIST FROM VICINITY OF LEE TROUGH WWD TOWARD COLD FRONT. CONTINUED HEATING/DESTABILIZATION SHOULD SUPPORT AN INCREASE IN TSTM COVERAGE ALONG THESE BOUNDARIES LATE THIS AFTERNOON INTO THE EVENING WITH A THREAT OF LOCALLY DAMAGING WINDS WITH THE MOST INTENSE STORMS. ...GA WWD INTO THE LOWER MS VALLEY... WIDESPREAD TSTMS HAVE DEVELOPED THIS AFTERNOON ALONG AND AHEAD OF SURFACE COLD FRONT AND PRE-FRONTAL TROUGH FROM GA WWD INTO LA. TEMPERATURES IN THE 90S COUPLED WITH DEWPOINTS IN THE UPPER 60 TO LOWER/MID 70S ARE CONTRIBUTING TO A MODERATELY UNSTABLE PRE-FRONTAL AIR MASS WITH MLCAPES OF 1500-2500 J/KG. VERTICAL SHEAR REMAINS WEAK...THOUGH NE-SW ORIENTED TSTM BANDS FROM CNTRL AL INTO CNTRL LA WILL HAVE THE POTENTIAL TO ORGANIZE COLD POOLS AS THEY MOVE/DEVELOP SEWD. DAMAGING WINDS WILL BE THE MAIN SEVERE WEATHER THREAT. ...UPPER MIDWEST... TSTMS ARE BECOMING MORE NUMEROUS THIS AFTERNOON FROM WI INTO LOWER MI SWD INTO NERN IA AND NRN IL...IN ASSOCIATION WITH A SHORT WAVE TROUGH TRANSLATING SEWD THROUGH THE REGION. THOUGH BOUNDARY LAYER DEWPOINTS ARE NOT PARTICULARLY HIGH /MID 50S TO LOWER 60S/...THE PRESENCE OF STEEP LOW-LEVEL LAPSE RATES AND MODESTLY COOL MID-LEVEL TEMPERATURES /I.E. -14 TO -16 C AT 500 MB/ ARE CONTRIBUTING TO MLCAPES OF 500-1000 J/KG. REGIONAL VWPS AND PROFILERS INDICATE THAT THE STRONGEST VERTICAL SHEAR EXISTS TO THE W OVER WRN MN/IA IN ASSOCIATION WITH MID AND HIGH-LEVEL JET STREAKS DIGGING SWD. THEREFORE...EXPECT THAT STORMS WILL REMAIN MULTICELLULAR AND CAPABLE OF GUSTY WINDS AND SOME MARGINALLY SEVERE HAIL THROUGH THE EVENING HOURS. ...WRN STATES... WATER VAPOR IMAGERY SHOWS TWO WELL-DEFINED IMPULSES ROTATING AROUND UPPER HIGH...ONE MOVING SWD THROUGH CNTRL CO...AND THE OTHER SHIFTING WWD THROUGH THE LOWER CO VALLEY. THESE FEATURES COUPLED WITH STRONG DIABATIC HEATING ALONG THE HIGHER TERRAIN WILL SUPPORT AN INCREASE IN TSTM ACTIVITY THIS AFTERNOON INTO TONIGHT. THE MOST INTENSE STORMS WILL BE CAPABLE OF SEVERE MICROBURSTS OWING TO THE STRONG EVAPORATIONAL COOLING POTENTIAL IN THE SUB-CLOUD LAYER. ..MEAD.. 07/22/2006  From swody1 at goshenarc.org Sun Jul 23 01:15:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 22 Jul 2006 21:15:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230111 SWODY1 SPC AC 230110 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0810 PM CDT SAT JUL 22 2006 VALID 230100Z - 231200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN NEW ENGLAND INTO THE CAROLINAS... ...SRN NEW ENGLAND INTO THE CAROLINAS... THUNDERSTORMS CONTINUE ALONG COLD FRONT FROM SRN NEW ENGLAND SWWD INTO GA AND THEN WSWWD INTO W TX. THOUGH A LIMITED/LOCAL SEVERE THREAT EXISTS ALONG THIS ENTIRE AREA...GREATEST THREAT EXISTS FROM SRN NEW ENGLAND INTO THE CAROLINAS WHERE MODERATE SWLY FLOW AT MID LEVELS IS INDICATED ALONG ERN PERIPHERY OF UPPER TROUGH. THOUGH THREAT SHOULD CONTINUE TO SLOWLY DECREASE WITH TIME AS DIURNAL STABILIZATION CONTINUES...LOCALLY-DAMAGING WINDS AND/OR MARGINAL HAIL -- AND PERHAPS EVEN AN ISOLATED/BRIEF TORNADO -- MAY STILL OCCUR WITH A FEW STRONGER STORMS/STORM CLUSTERS. ...THE SOUTHWEST/GREAT BASIN... SCATTERED THUNDERSTORMS CONTINUE FROM CO/NM ACROSS PARTS OF AZ AND UT INTO NV/CA/ORE/SRN ID -- ALL WITHIN LARGE-SCALE ANTICYCLONIC FLOW AROUND RIDGE CENTERED OVER THE GREAT BASIN. STORMS WILL LIKELY CONTINUE FOR SEVERAL HOURS -- AS SEVERAL VORTICITY MAXIMA CONTINUE ROTATING AROUND THE RIDGE. THOUGH WEAK FLOW AND MARGINAL INSTABILITY IN MOST AREAS WILL CONTINUE TO LIMIT THE SEVERE THREAT...A LOCALLY-DAMAGING GUST OR MARGINAL HAIL EVENT MAY OCCUR WITH A COUPLE OF THE STRONGEST STORMS. ...SRN UPPER GREAT LAKES REGION... THUNDERSTORMS CONTINUE A GENERAL DIURNAL DECREASE ACROSS THE UPPER MIDWEST/SRN UPPER GREAT LAKES REGION ATTM. THOUGH A FEW MARGINAL SEVERE EVENTS MAY OCCUR IN THE NEXT 1 TO 2 HOURS...THREAT SHOULD CONTINUE TO WANE WITH TIME. ..GOSS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 06:04:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 02:04:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230601 SWODY1 SPC AC 230559 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1259 AM CDT SUN JUL 23 2006 VALID 231200Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CAROLINAS AND INTO SERN VA... ...SYNOPSIS... UPPER PATTERN IS FORECAST TO DEAMPLIFY SLOWLY THIS PERIOD...AS WRN RIDGE FLATTENS WITH TIME AND ERN TROUGH LIFTS NEWD AND TAKES ON A NEGATIVE TILT. AT THE SURFACE...COLD FRONT WILL CONTINUE MOVING EWD ACROSS THE ATLANTIC COAST STATES WHILE LINGERING ACROSS THE GULF COAST REGION. A SECOND/WEAK FRONT SHOULD MOVE SEWD INTO THE UPPER MS VALLEY/SWD INTO MT THROUGH THE PERIOD. ...CAROLINAS/SERN VA... COLD FRONT MOVING SLOWLY EWD ACROSS THE E COAST STATES SHOULD YIELD SCATTERED THUNDERSTORMS...AS MOIST AIRMASS DESTABILIZES THROUGH THE AFTERNOON. INSTABILITY SHOULD REMAIN SOMEWHAT LIMITED DUE TO WEAK LAPSE RATES ACROSS THIS REGION ALONG WITH EXISTING CLOUDS/CONVECTION. HOWEVER...AMPLE DEEP-LAYER SHEAR -- AIDED BY 30 TO 40 KT WSWLY FLOW AT MID-LEVELS NEAR BASE OF UPPER TROUGH -- WILL SUPPORT ORGANIZED/SEVERE STORMS. THREAT SHOULD DIMINISH THROUGH THE EVENING AS AIRMASS STABILIZES AND FRONT MOVES OFFSHORE. A LESSER THREAT MAY EXTEND SWD ACROSS GA AND INTO NERN FL...AS WEAKER SHEAR WITH SWD EXTENT LIMITS POTENTIAL FOR ORGANIZATION. ...N CENTRAL CONUS... COLD FRONT IS FORECAST TO MOVE SEWD ACROSS THE UPPER MS VALLEY/SWD INTO MT/ND...AS SEVERAL UPPER DISTURBANCES MOVE SEWD WITHIN FAST NWLY FLOW ALOFT. THOUGH CAP SHOULD HINDER CONVECTIVE DEVELOPMENT ACROSS MUCH OF THE REGION...MARGINAL INSTABILITY COMBINED AND AMPLE LOW-LEVEL CONVERGENCE SHOULD YIELD SCATTERED STORM DEVELOPMENT ACROSS PARTS OF NRN MN AND INTO NWRN WI. STORM INITIATION IS LESS CERTAIN WITH WWD EXTENT ACROSS ND...THOUGH STRONGER FEATURE FORECAST TO MOVE INTO NWRN MT MAY YIELD A SECOND AREA OF MORE CONCENTRATED CONVECTIVE POTENTIAL. OVERALL HOWEVER...MARGINAL INSTABILITY AND LIMITED CONVECTIVE COVERAGE SUGGESTS ONLY A LOW-PROBABILITY THREAT ACROSS THIS REGION. ...THE SOUTHWEST... NELY FLOW ALOFT IS FORECAST ACROSS NM/ERN AZ THIS PERIOD...WITHIN SERN QUADRANT OF UPPER RIDGE. AS STORMS DEVELOP WITHIN ENVIRONMENT FEATURING MARGINAL INSTABILITY AND A DEEPLY-MIXED BOUNDARY LAYER...A LIMITED THREAT FOR LOCALLY-DAMAGING WINDS APPEARS TO EXIST. GREATEST THREAT APPEARS TO EXIST ACROSS WRN NM/SERN AZ WHERE SLIGHTLY STRONGER FLOW ALOFT IS EXPECTED...BUT OVERALL THREAT SHOULD REMAIN BELOW SLIGHT RISK CRITERIA. ...SRN ID AND VICINITY... THUNDERSTORMS ARE EXPECTED TO DEVELOP INVOF UPPER VORT MAX FORECAST ACROSS SRN ID DURING THE AFTERNOON...WITHIN AIRMASS FEATURING DEEP BOUNDARY LAYER AND MARGINAL INSTABILITY. THOUGH WEAK FLOW AND LIMITED INSTABILITY SUGGEST THAT OVERALL SEVERE THREAT SHOULD REMAIN LOW...A FEW STRONGER CELLS MAY BE CAPABLE OF LOCALLY STRONG WIND GUSTS AND MARGINAL HAIL THROUGH EARLY EVENING. ...LOWER GREAT LAKES REGION... AS COLD TROUGH SPREADS EWD ACROSS THE LOWER GREAT LAKES REGION...AFTERNOON HEATING WILL CONTRIBUTE TO MARGINAL DESTABILIZATION. SCATTERED/LOW-TOPPED STORMS SHOULD DEVELOP AND MOVE ESEWD WITHIN DEEP-LAYER WNWLY FLOW. THOUGH LIMITED INSTABILITY SHOULD MODULATE UPDRAFT INTENSITY...A LOCAL THREAT FOR HAIL AND/OR GUSTY WINDS IS ANTICIPATED WITH STRONGER CELLS THROUGH EARLY EVENING. ..GOSS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 12:43:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 08:43:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231240 SWODY1 SPC AC 231238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT SUN JUL 23 2006 VALID 231300Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF GA...THE CAROLINAS...AND SOUTHEAST VA... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF MN...WI...AND UPPER MI... ...GA/SC INTO MID ATLANTIC REGION... LARGE UPPER RIDGE WILL CONTINUE TO DOMINATE THE WEATHER OVER THE WESTERN STATES TODAY...WHILE BROAD TROUGH AND MODERATELY STRONG CYCLONIC FLOW ALOFT PROMOTES SCATTERED THUNDERSTORMS FROM THE CENTRAL GULF STATES INTO THE MID ATLANTIC REGION. EARLY VISIBLE IMAGERY SHOWS BROKEN HIGH CLOUDS OVER THIS AREA...WHICH SHOULD ALLOW FAIRLY STRONG HEATING FROM GA/SC INTO SOUTHEAST VA. SURFACE DEWPOINTS NEAR 70F...CAPE VALUES OF 1500-2000 J/KG...AND WEAK CAPPING WILL AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS BY MID AFTERNOON. WESTERLY MID LEVEL WINDS OF 25-35 KNOTS WILL HELP ORGANIZE STORMS IN THIS REGION...WITH BANDS OF CONVECTION CAPABLE OF DAMAGING WINDS AND HAIL EXPECTED. SEA BREEZE INTERACTIONS MAY ALSO ENHANCE SEVERE THREAT NEAR THE CAROLINA COAST THIS AFTERNOON. ...MN/WI/UPPER MI... WATER VAPOR IMAGERY SHOWS FAST-MOVING SHORTWAVE TROUGH DIGGING SOUTHEASTWARD ACROSS MANITOBA/SASKATCHEWAN. THIS FEATURE WILL LIKELY RESULT IN THUNDERSTORM DEVELOPING THIS AFTERNOON NEAR WINNIPEG...WITH ACTIVITY SPREADING SOUTHEASTWARD INTO PARTS OF NORTHERN MN/NORTHWEST WI/UPPER MI. STEEP MID LEVEL LAPSE RATES ARE FORECAST IN THIS REGION...ALONG WITH SUFFICIENT VERTICAL SHEAR FOR SUPERCELLS/BOWS. LARGE HAIL AND DAMAGING WINDS ARE POSSIBLE IN STRONGER STORMS THIS AFTERNOON AND EVENING. ...NORTHERN ROCKIES... MODERATE WESTERLY FLOW IS PRESENT TODAY OVER THE NORTHERN ROCKIES...WITH UPPER LEVEL IMPULSE ROTATING OVER TOP OF RIDGE INTO ID/MT. SCATTERED THUNDERSTORMS ARE LIKELY TO FORM AHEAD OF SYSTEM THIS AFTERNOON...WHERE HOT SURFACE TEMPERATURES AND INVERTED-V THERMODYNAMIC PROFILES WILL SUPPORT A RISK OF GUSTY WINDS. ...SOUTHWEST STATES... BAND OF NORTHERLY/NORTHEASTERLY MID LEVEL WINDS EXTENDS FROM CO INTO SOUTHERN AZ. THIS AXIS WILL LIKELY SEE SCATTERED AFTERNOON THUNDERSTORMS. STEEP LOW LEVEL LAPSE RATES WILL PROMOTE A RISK OF GUSTY WINDS IN STRONGER CELLS...AND STRONGER MID LEVEL WINDS WILL HELP ORGANIZE STORMS AND MOVE THEM OFF THE HIGHER TERRAIN. ..HART/CROSBIE.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 16:35:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 12:35:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231631 SWODY1 SPC AC 231630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT SUN JUL 23 2006 VALID 231630Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS EASTERN CAROLINAS... ...THERE IS A SLGT RISK OF SVR TSTMS MN WI AND UPPER MI... ...CAROLINAS... BROAD TROUGH ERN U.S. GRADUALLY FILLS AS S/WV TROUGH CURRENTLY OH VALLEY CONTINUES ENEWD ACROSS NEW ENGLAND BY 12Z MON. FRONTAL ZONE HAS SHIFTED SEWD EXTENDING FROM SRN VA ACROSS NRN GULF STATES TO CENTRAL TX. CONSIDERABLE CLOUDINESS ALONG AND SOME DISTANCE IN ADVANCE OF FRONT...HOWEVER ERN NC PARTICULARLY WILL BE ABLE TO HEAT UP WITH MINIMAL CLOUD COVER. WITH DEWPOINTS WELL INTO THE 70S AND TEMPERATURES BY MID AFTERNOON UPPER 80S...MLCAPES WILL CLIMB TO 2000 J/KG WITH STEEP LOW LEVEL LAPSE RATES. WITH S/WV PASSING BY TO THE NORTH...DEEP LAYER SHEAR OF 20-30KT WILL SUPPORT MULTICELL STORM DEVELOPMENT. INITIATION WILL BE MOST FAVORABLE ALONG SEA BREEZE FRONT AND IN AREAS THAT EXPERIENCE STRONGEST HEATING. WITH MARGINAL SHEAR AND MID LEVEL LAPSE RATES GENERALLY AROUND 6C/KM WET DOWNBURSTS AND MARGINALLY SEVERE HAIL SHOULD BE THE LIMIT OF SEVERE THREAT FROM MID AFTERNOON TIL AROUND SUNSET. ...MN WI AND UPPER MI... S/WV TROUGH NOTED ON WV IMAGERY DROPPING SEWD ACROSS CENTRAL MANITOBA TOWARD WRN ONTARIO. CURRENT WARM ADVECTION CLOUDINESS/PCPN MN ARROWHEAD AHEAD OF TROUGH SHOULD GRADUALLY SHIFT EWD THIS AFTERNOON ALLOWING HEATING AND STEEPENING LOW LEVEL LAPSE RATES TO SPREAD EWD ACROSS NRN MN. VEERING SHEAR PROFILES AHEAD OF S/WV TROUGH WILL PROVIDE FAVORABLE CONDITIONS FOR POTENTIAL FOR ORGANIZED STORMS TO DEVELOP OVER SRN MANITOBA AND DROP SEWD DURING AFTERNOON/EVENING INTO NRN MN AND EVENTUALLY NRN WI/WRN UP OF MI. INSTABILITY WILL BE SOMEWHAT LIMITED GIVEN AVAILABLE LOW LEVEL MOISTURE...HOWEVER STEEPENING LAPSE RATES SHOULD RAISE MLCAPES TO NEAR 1000 J/KG BY MID AFTERNOON. HAVE EXTENDED EARLIER SLIGHT RISK WWD ACROSS NRN MN WHERE LOW LEVEL BOUNDARIES COULD SET UP ON EDGE OF CURRENT BOUNDARY WATERS PCPN. WITH 30-40KT OF DEEP LAYER SHEAR...SHORT LINES/BOWS COULD EVOLVE OUT OF STORMS MOVING INTO NRN MN FOR A GREATER WIND DAMAGE THREAT. ...WRN U.S... VERY LARGE UPPER HIGH CONTINUES TO CONTROL WEATHER WRN U.S. CONSIDERABLE MID LEVEL MOISTURE CIRCULATING AROUND THE HIGH AND WITH THE INTENSE SURFACE HEATING...CONTINUES THE THREAT OF ISOLATED DIURNAL SEVERE STORMS. THE THREAT WILL BE MODULATED WHERE FULL HEATING CAN OCCUR AND VICINITY HIGHER TERRAIN. LARGE AREAS OF MID CLOUDINESS WHILE EXPECTED TO THIN WITH TIME...WILL LIMIT HEATING IN SOME REGIONS. HAVE NOT TRIED TO PINPOINT ANY PARTICULAR AREA WHERE POTENTIAL FOR HIGH BASED DOWNBURSTS OR MARGINAL HAIL COULD OCCUR. THUS THE LARGE AREA OF LOW SEVERE PROBABILITIES. ..HALES/GRAMS.. 07/23/2006  From swody1 at goshenarc.org Sun Jul 23 19:59:30 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 15:59:30 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 231955 SWODY1 SPC AC 231953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT SUN JUL 23 2006 VALID 232000Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER NRN MN...NRN WI AND THE WRN UP OF MI... ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER PORTIONS OF THE SRN ATLANTIC COAST... ...NRN MN/NRN WI/WRN UP OF MI... AFTERNOON WATER VAPOR IMAGERY SHOWS AMPLIFYING SHORT WAVE TROUGH DIGGING SEWD INTO WRN ONTARIO WITH A WEAKER SRN IMPULSE OVER FAR SERN MANITOBA. CONSIDERABLE CLOUDINESS HAS LIMITED DAYTIME HEATING OVER MUCH OF THE ARROWHEAD...THOUGH AIR MASS FROM N OF HIB WWD HAS WARMED INTO THE UPPER 80S/LOWER 90S. THIS HEATING COUPLED WITH RELATIVELY STEEP MID-LEVEL LAPSE RATES AND MODEST BOUNDARY LAYER MOISTURE ARE CONTRIBUTING TO A MODERATELY UNSTABLE ENVIRONMENT W OF THICKER CLOUD SHIELD WITH MLCAPES OF AROUND 1000 J/KG. BASED ON SATELLITE TRENDS AND LATEST SHORT TERM MODEL GUIDANCE...IT APPEARS THAT TSTMS WILL INCREASE IN COVERAGE LATE THIS AFTERNOON INTO TONIGHT ALONG DIFFERENTIAL HEATING BOUNDARY AND COLD FRONT /NOW PUSHING INTO NWRN MN/. CURRENT DLH VWP AND FORECAST SOUNDINGS INDICATE PRONOUNCED LOW-LEVEL HODOGRAPH CURVATURE WITH 30-40 KTS OF DEEP-LAYER SHEAR. THUS...EXPECT THE POTENTIAL FOR ORGANIZED SEVERE STORMS...INCLUDING SUPERCELLS CAPABLE OF DAMAGING WINDS AND LARGE HAIL. THIS THREAT MAY TEND TO DIMINISH BY LATE EVENING INTO OVERNIGHT AS BOUNDARY LAYER SLOWLY STABILIZES. A FEW OF THE MORE INTENSE ELEVATED STORMS WILL REMAIN CAPABLE OF SOME HAIL OVERNIGHT. FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1614. ...SRN ATLANTIC COAST... LINGERING CLOUDINESS HAS SLOWED DESTABILIZATION OF AIR MASS AHEAD OF WEAKENING FRONT ACROSS THE PIEDMONT AND COASTAL PLAIN THROUGH EARLY AFTERNOON. MORE RECENTLY...CLOUDS HAVE THINNED...ALLOWING FOR STRONGER DIABATIC HEATING WHICH HAS COMBINED WITH A MOIST BOUNDARY LAYER TO INCREASE MLCAPES TO 1000-2000 J/KG. AREA VWPS AND RUC OBJECTIVE FIELDS INDICATE THAT MID-LEVEL WINDS ARE GRADUALLY WEAKENING WITH THE SLOW NEWD MOVEMENT OF UPPER TROUGH. HOWEVER...AN AXIS OF 30-35 KT WSWLY FLOW STILL EXISTS ACROSS NRN NC WHICH IS ENHANCING SHEAR ACROSS NRN PORTIONS OF SLIGHT RISK AREA. GIVEN THE MODERATE INSTABILITY...EXPECT THAT STORMS SHOULD CONTINUE TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE LATE AFTERNOON AND EARLY EVENING HOURS WITH THE MAIN THREAT BEING LOCALLY DAMAGING WINDS WITH ANY OF THE MORE INTENSE DOWNBURSTS. FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1613. ..MEAD.. 07/23/2006  From swody1 at goshenarc.org Mon Jul 24 01:10:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 23 Jul 2006 21:10:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240107 SWODY1 SPC AC 240105 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT SUN JUL 23 2006 VALID 240100Z - 241200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS NRN MN/NWRN WI... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN CAROLINAS/E CENTRAL GA... ...NRN MN/NWRN WI... STRONG STORMS CONTINUE MOVING SEWD INTO NWRN WI ATTM...ROUGHLY ALONG WARM FRONT. HOWEVER...AIRMASS BECOMES LESS FAVORABLE WITH SWD EXTENT ACROSS WI...SO THIS CLUSTER OF STORMS SHOULD WEAKEN. ADDITIONAL DEVELOPMENT CANNOT BE RULED OUT ACROSS NRN MN...WHERE AMPLE INSTABILITY AND MODERATE NWLY FLOW EXISTS. HOWEVER...CONDITIONAL SEVERE POTENTIAL ACROSS THIS REGION SHOULD CONTINUE TO DECREASE AS BOUNDARY LAYER STABILIZES. ...ERN CAROLINAS/E CENTRAL GA... LIMITED SEVERE THREAT CONTINUES ACROSS THIS REGION...AS MOIST/UNSTABLE ENVIRONMENT PERSISTS AHEAD OF FRONT. THOUGH SHEAR REMAINS SUFFICIENT FOR ORGANIZED STORMS...STRONGEST CONVECTION HAS REACHED THE NC COAST...AND WILL CONTINUE MOVING OFFSHORE. REMAINING THREAT SHOULD SLOWLY DIMINISH THIS EVENING. ...CO/THE SOUTHWEST... WIDESPREAD THUNDERSTORMS ARE OCCURRING ONCE AGAIN ACROSS MUCH OF THE WEST -- WITHIN LARGE-SCALE ANTICYCLONIC CIRCULATION. STORMS REMAIN GENERALLY LIMITED IN INTENSITY...DUE TO WEAK INSTABILITY/WARM TEMPERATURES ALOFT. THOUGH A STRONGER STORM OR TWO MAY PRODUCE LOCALLY-GUSTY WINDS OR MARGINAL HAIL...THREAT WILL CONTINUE TO DECREASE THROUGH LATE EVENING. ..GOSS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 06:11:16 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 02:11:16 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 240607 SWODY1 SPC AC 240606 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0106 AM CDT MON JUL 24 2006 VALID 241200Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER GREAT LAKES WWD INTO PARTS OF SD/NEB... ...SYNOPSIS... LESS-AMPLIFIED UPPER PATTERN IS FORECAST THIS PERIOD...THOUGH OVERALL FLOW FIELD -- FEATURING A RIDGE OVER THE SOUTHWEST AND A TROUGH OVER THE ERN CONUS -- WILL PERSIST. AT THE SURFACE...MODELS DIFFER IN LOCATION OF N CENTRAL U.S. BAROCLINIC ZONE. IN GENERAL...THIS FRONT SHOULD LIE FROM THE UPPER GREAT LAKES WSWWD INTO NEB...AND THEN NWWD ACROSS THE NRN HIGH PLAINS INTO MT. THIS BOUNDARY SHOULD SERVE AS A FOCUS FOR SCATTERED STRONG/LOCALLY-SEVERE STORMS...AS BELT OF MODERATE WNWLY MID-LEVEL FLOW SHOULD ALSO RESIDE ACROSS THIS REGION. ...UPPER GREAT LAKES REGION WWD INTO ERN SD/NERN NEB... CONVECTION IS LIEKLY TO BE ONGOING AT THE START OF THE PERIOD ACROSS PARTS OF THE UPPER GREAT LAKES/UPPER MS VALLEY REGION...BUT MARGINAL TO MODERATE DESTABILIZATION IS ANTICIPATED THROUGH THE AFTERNOON NEAR AND S OF THE FRONT. AS A RESULT...SCATTERED STORMS SHOULD REDEVELOP INVOF SURFACE BOUNDARY AS UPPER SHORT-WAVE TROUGH MOVES ACROSS THE AREA. THOUGH STRONGEST MID-LEVEL FLOW WILL LIKELY REMAIN FROM LK SUPERIOR NWD...MODERATE WLY/WNWLY FLOW THROUGH A DEEP LAYER APPEARS SUPPORTIVE ISOLATED SEVERE STORMS/STORM CLUSTERS...CAPABLE OF PRODUCING LOCALLY-DAMAGING WINDS AND HAIL. STORM COVERAGE SHOULD DECREASE WITH WWD EXTENT ACROSS SD AND NEB...WHERE PROGRESSIVELY STRONGER CAP AND WEAKER LARGE-SCALE FORCING ARE ANTICIPATED. THREAT WILL SLOWLY WANE THROUGH LATE EVENING/OVERNIGHT AS AIRMASS DIURNALLY STABILIZES. ...MT INTO THE DAKOTAS... MODELS SUGGEST THAT A SECOND SHORT-WAVE TROUGH SHOULD MOVE ACROSS MT DURING THE DAY...WITH ASSOCIATED WARM ADVECTION ANTICIPATED ACROSS THE NRN HIGH PLAINS. THOUGH INSTABILITY SHOULD BE LIMITED...ISOLATED STORM DEVELOPMENT IS EXPECTED. WITH MODERATE WNWLY FLOW AT MID LEVELS...SHEAR WILL SUPPORT A FEW STRONGER STORMS -- WITH LOCALLY-DAMAGING WINDS LIKELY TO BE THE GREATER SEVERE THREAT GIVEN FAIRLY DEEP/DRY SUB-CLOUD LAYER. SOME HINT EXISTS IN THE MODELS THAT ENHANCED WARM ADVECTION OVER THE NRN HIGH PLAINS MAY RESULT IN A LOCALLY-GREATER THREAT...BUT QUESTIONS REGARDING DEGREE OF INSTABILITY AND TIMING OF UPPER FEATURE PRECLUDE AN UPGRADE TO SLIGHT RISK ATTM. ..GOSS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 12:29:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 08:29:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241226 SWODY1 SPC AC 241224 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0724 AM CDT MON JUL 24 2006 VALID 241300Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MIDWEST ACROSS THE GREAT LAKES STATES... WEST-NORTHWEST FLOW PATTERN WILL BE PRESENT TODAY FROM THE NORTHERN PLAINS ACROSS THE GREAT LAKES REGION. WATER VAPOR IMAGERY SHOWS SEVERAL WEAK IMPULSES EMBEDDED WITHIN FLOW THAT WILL HELP TO INITIATE SCATTERED THUNDERSTORMS FROM THE NORTHERN ROCKIES INTO MI. OTHER SCATTERED CONVECTION IS EXPECTED TODAY BENEATH UPPER RIDGE OVER THE WESTERN STATES...AND OVER THE SOUTHEAST IN PLUME OF TROPICAL AIR. ...GREAT LAKES AND UPPER MIDWEST... SHORTWAVE TROUGH NOW ROTATING TOWARD LAKE SUPERIOR WILL PROGRESS INTO MI TODAY. RELATIVELY STRONG WESTERLY LOW LEVEL WINDS AHEAD OF SYSTEM WILL HELP TRANSPORT WARM/MOIST AIRMASS INTO REGION WITH AFTERNOON DEWPOINTS WELL INTO THE 60S AND MLCAPE VALUES OVER 1500 J/KG. THUNDERSTORMS ARE EXPECTED TO DEVELOP BY MID/LATE AFTERNOON ALONG WEAK SURFACE BOUNDARY FROM WEST CENTRAL MN...ACROSS WI...INTO NORTHERN LOWER MI. THIS ACTIVITY WILL LIKELY PERSIST THROUGH THE EVENING...SPREADING ACROSS THE REMAINDER OF LOWER MI. FORECAST SOUNDINGS SUGGEST FAVORABLE DEEP LAYER VERTICAL SHEAR FOR ORGANIZED/SEVERE STORMS CAPABLE OF HAIL AND DAMAGING WINDS. ...NORTHERN PLAINS... STRONG DAYTIME HEATING WILL HELP ISOLATED THUNDERSTORM DEVELOPMENT FROM MN WESTWARD ACROSS THE DAKOTAS. HOWEVER...WEAKER DEEP LAYER FLOW AND WARMER TEMPERATURES ALOFT WILL TEND TO MINIMIZE ORGANIZED SEVERE THREAT IN THESE AREAS. ...NORTHERN ROCKIES... SERIES OF WEAK SHORTWAVE TROUGHS ARE ROTATING AROUND RIDGE CENTERED OVER UT. ONE FEATURE IS NOW OVER CENTRAL ORE...AND WILL LIKELY MOVE INTO ID BY THIS AFTERNOON. ENHANCED LIFT AHEAD OF FEATURE WILL AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER THE MOUNTAINS OF ID/WESTERN MT. MEAGER LOW LEVEL MOISTURE WILL LIMIT CAPE. HOWEVER...DEEP MIXED BOUNDARY LAYER SUGGESTS A THREAT OF GUSTY WINDS IN STRONGER CELLS. ..HART/CROSBIE.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 16:19:58 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 12:19:58 -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 MON JUL 24 2006 VALID 241630Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS MIDWEST AND PORTIONS OF GREAT LAKES... ...GREAT LAKES AND UPPER MIDWEST... THE SEVERE THUNDERSTORM RISK ACROSS MN EWD TO MI THIS AFTERNOON WILL BE PRIMARILY DRIVEN BY BUOYANCY/INSTABILITY. THE DEEP LAYER SHEAR WILL FOR THE MOST PART BE MARGINAL AS THE UPPER SYSTEM CURRENTLY OVER ONTARIO CONTINUES EWD. COLD FRONT EXTENDING SWWD ACROSS LS/NWRN WI TO CENTRAL SD WILL CONTINUE SEWD AND PROVIDE FOCUS FOR INITIATION OF STRONG/SEVERE THUNDERSTORMS BY MID/LATE AFTERNOON. WITH TEMPS CLIMBING TO 90F AIR MASS WILL BECOME MODERATELY UNSTABLE WITH MLCAPES TO 2500 J/KG ACROSS SRN MN/WI AND 2000 J/KG LWR MI. AS MENTIONED PROGGED DEEP LAYER SHEAR AROUND 20KT MN/WI WHERE INSTABILITY WILL BE GREATEST THIS AFTERNOON...RANGING UPWARD TO 30-35KT OF SHEAR NRN LWR MI WITH A LITTLE LESS INSTABILITY..SUPPORTS GENERALLY MULTICELL STORM MODE. THUS A THREAT OF LOCALIZED DAMAGING WINDS AND MARGINALLY SEVERE HAIL EXPECTED TO DEVELOP BY MID AFTERNOON ALONG/AHEAD OF FRONT SRN MN/WI AND THEN SPREAD EWD INTO PORTIONS OF LOWER MI. SEVERE THREAT SHOULD DECREASE AFTER SUNSET GIVEN THE WEAKENING SHEAR AND MINIMAL UPPER SUPPORT. ...SRN AZ... EXAMINING 12Z SOUNDINGS AND LACK OF CLOUD COVER TO SLOW HEATING...THUNDERSTORMS SHOULD DEVELOP EARLY AFTERNOON CENTRAL MTNS AND HIGHER TERRAIN SERN AZ. WHILE MLCAPE OVER DESERT VALLEY WILL BE GENERALLY LESS THAN 1000 J/KG...THE DEEP BOUNDARY LAYER AS TEMPS HEAT TO 110F ALONG WITH DCAPES APPROACHING 2000 J/KG WILL SUPPORT PROPAGATION OF STORMS OFF HIGHER TERRAIN IN THE PREVAILING ELY STEERING FLOW. STRONG...POSSIBLY DAMAGING OUTFLOW WINDS EXPECTED TO SPREAD WWD INTO LOWER ELEVATIONS LATE THIS AFTERNOON AND EVENING. ...NRN PLAINS WWD TO WRN MT... AS LARGE UPPER HIGH OVER WRN U.S. GRADUALLY FLATTENS...MID LEVEL WLYS INCREASE ACROSS NRN TIER OF STATES. WEAK UPPER IMPULSES...ONE NOW MOVING EWD INTO WRN MT WILL AID DEVELOPMENT OF HIGH BASED THUNDERSTORMS. WHILE MOISTURE IS MARGINAL...STRONG HEATING/STEEP LAPSE RATES AND 30KT OF DEEP LAYER SHEAR WILL SUPPORT LOCAL STRONG DOWNBURSTS WITH ANY STORM THAT CAN DEVELOP ACROSS MT AND ADJACENT HIGH PLAINS LATER THIS AFTERNOON/EVENING. ..HALES/GRAMS.. 07/24/2006  From swody1 at goshenarc.org Mon Jul 24 19:53:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 15:53:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 241948 SWODY1 SPC AC 241946 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0246 PM CDT MON JUL 24 2006 VALID 242000Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER GREAT LAKES AND UPPER MS VALLEY.... ...SYNOPSIS... MINOR SHORTWAVE IS EMBEDDED WITHIN NORTHWEST FLOW ACROSS PARTS OF THE UPPER MIDWEST. LATEST SURFACE ANALYSIS SHOWS COLD FRONT EXTENDING FROM CENTRAL LAKE SUPERIOR SWWD ACROSS NWRN WI AND CENTRAL MN INTO NRN SD. MEANWHILE...LARGE MID/UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE SWRN U.S. ...PARTS OF THE GREAT LAKES AND UPPER MS VALLEY... STRONG/SEVERE THUNDERSTORMS EXTENDED FROM NRN LAKE MI WWD THRU NRN WI ALONG FRONTAL BOUNDARY. AIR MASS S OF THIS BOUNDARY IS VERY MOIST...WARM AND UNSTABLE WITH DEW POINTS IN THE MID/UPR 60S AND MLCAPE BETWEEN 1500 AND 2500 J/KG. LATEST RUC SOUNDING DATA SHOWS GRB WITH A SFC-3KM LAPSE RATE OF 8.5C/KM AND A DCAPE OF 1074 J/KM. WHILE SOME HAIL IS POSSIBLE...THIS WOULD INDICATE THAT THE MAIN THREAT WILL BE DAMAGING WINDS. FURTHER WEST...MODELS INDICATE THAT STORMS COULD DEVELOP THIS EVENING EAST OF SURFACE LOW OVER CENTRAL SD AND MOVE ALONG CONVECTIVE BOUNDARY AS INDICATED BY ELEVATED STORMS OVER SWRN MN. THIS ACTIVITY AS WELL LOOKS TO MOSTLY A THREAT FOR DAMAGING WINDS THRU EARLY TONIGHT. ...PARTS OF SERN AZ... NELY/ELY FLOW ALOFT REMAINS OVER ERN AND SRN AZ ACCORDING TO LATEST WATER VAPOR IMAGERY. SCATTERED THUNDERSTORMS CAN BE EXPECTED AGAIN LATER THIS AFTERNOON AND EARLY TONIGHT WHERE VERY STEEP MID LEVEL LAPSE RATES ARE NEAR 8.5C/KM. SOME OF THESE STORMS COULD PRODUCE SOME STRONG WIND GUSTS AS DCAPE VALUES ARE JUST ABOVE 1500 J/KG IN REGIME OF LARGE TEMP AND DEW POINT SPREADS OF AROUND 50 DEGREES. ..MCCARTHY.. 07/24/2006  From swody1 at goshenarc.org Tue Jul 25 01:49:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 24 Jul 2006 21:49:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250054 SWODY1 SPC AC 250053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT MON JUL 24 2006 VALID 250100Z - 251200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE GREAT LAKES AND UPPER MS VALLEY... ...GREAT LAKES AND UPPER MS VALLEY... WEAK COLD FRONT EXTENDED FROM THE ERN U.P. SWWD INTO NRN WI/SRN MN/SRN SD THIS EVENING. SCATTERED STRONG/SEVERE THUNDERSTORMS WERE LOCATED ALONG AND SOUTH OF THE FRONT WHERE THE AIR MASS WAS MODERATELY UNSTABLE. THE AMOUNT OF INSTABILITY AND UNIDIRECTIONAL WNWLY WINDS THROUGHOUT MUCH OF THE TROPOSPHERE FAVOR SMALL THUNDERSTORM LINES WITH THE POTENTIAL FOR MARGINALLY SEVERE WINDS/HAIL. HOWEVER...STORM INTENSITIES AND COVERAGE SHOULD DECREASE DURING THE EVENING AS STORM OUTFLOWS GRADUALLY STABILIZE/COOL THE BOUNDARY LAYER. SEVERE STORMS WERE ALSO LOCATED ACROSS SERN SD...WHERE STRONGLY VEERING WIND PROFILES WERE RESULTING IN STRONGER DEEP LAYER SHEAR THAN ACROSS THE GREAT LAKES. THESE STORMS WERE LOCATED NEAR THE COLD FRONT AND ON THE ERN EDGE OF A VERY HOT AIR MASS THAT STRETCHED ACROSS SRN SD/NRN NEB. THIS HEAT ENERGY PLUS THE PRESENCE OF THE LOW LEVEL JET IS LIKELY TO SUSTAIN THIS CONVECTION THROUGH THE EVENING WITH THE POTENTIAL FOR WIND/HAIL DAMAGE...REFERENCE WW 641. ...CENTRAL AZ... THE CENTER OF THE UPPER RIDGE WAS LOCATED NEAR THE FOUR CORNERS AREA THIS EVENING...WITH NELY/ELY MID LEVEL WINDS LOCATED ACROSS SRN AZ. NUMEROUS THUNDERSTORMS WERE LOCATED ACROSS THE NRN HALF OF THE STATE AND ARE LIKELY TO PROPAGATE SLOWLY SWWD. VERY HOT TEMPERATURES AND VERY STEEP LOW LEVEL LAPSE RATES MAY SUPPORT ISOLATED STRONG/SEVERE WIND GUSTS FOR THE NEXT COUPLE OF HOURS. ...NRN MT... CLUSTER OF STORMS WILL MOVE ESEWD THROUGH THE EVENING. DEEP MIXED BOUNDARY LAYER MAY SUPPORT STRONG WIND GUSTS FOR THE NEXT HOUR OR SO. ..IMY.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 05:17:02 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 01:17:02 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250513 SWODY1 SPC AC 250511 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1211 AM CDT TUE JUL 25 2006 VALID 251200Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS IN NRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MIDWEST/WRN GREAT LAKES... ...SYNOPSIS... A COUPLE OF SHORTWAVE TROUGHS WILL DIG SEWD FROM THE NRN ROCKIES INTO THE GREAT LAKES AREA...WHERE A WEAK LONGWAVE TROUGH IS CURRENTLY SITUATED. THE FIRST SHORTWAVE TROUGH WILL WEAKEN AND MOVE INTO NRN MN LATE TUESDAY AFTERNOON...WHILE A STRONGER TROUGH DIVES SEWD TO NEAR LAKE SUPERIOR BY WED MORNING. IN ASSOCIATION WITH THESE TROUGHS...A WEAK COLD FRONT WILL PUSH EWD INTO THE ERN DAKOTAS DURING THE AFTERNOON...WHILE THE REMNANTS OF THE FRONT THAT MOVED ACROSS MN/WI MONDAY...ARE FORECAST TO STRETCH ACROSS CENTRAL MN/WI DURING THE AFTERNOON HOURS. OTHERWISE...AN UPPER TROUGH IN QUEBEC WILL BRUSH NEW ENGLAND AND A MID/UPPER LEVEL TROUGH OVER THE NWRN GULF OF MEXICO IS FORECAST TO LIFT SLOWLY NWD TOWARD THE TX COAST. ...NRN NEW ENGLAND... STRONG FORCING ASSOCIATED WITH QUEBEC TROUGH SHOULD RESULT IN A BAND OF THUNDERSTORMS TO MOVE EWD ACROSS THE REGION TODAY. DUE TO STRONG WINDS ALOFT...DEEP LAYER SHEAR WILL BE SUFFICIENT FOR SEVERE STORMS. THE NEGATIVE FOR SEVERE WEATHER WILL BE POOR LAPSE RATES...WEAK INSTABILITY...MLCAPES LESS THAN 1000 J/KG AND THE POSSIBILITY OF HEATING BEING RESTRICTED DUE TO CLOUDS. HOWEVER... IF SOME HEATING OCCURS AND THE STORMS DEVELOP INTO BANDS/LINES... THEN THE ENVIRONMENTAL WINDS WOULD BE SUPPORTIVE OF ISOLATED SEVERE WIND GUSTS. THE STORMS SHOULD END BY EARLY EVENING AS THE MAIN LARGE SCALE LIFTING MOVES NEWD OUT OF THE AREA. ...UPPER MIDWEST/WRN GREAT LAKES REGION... THOUGH CONVECTIVE INITIATION IS SOMEWHAT UNCLEAR ACROSS THE AREA...THINK STORMS WILL BE INITIATED TUESDAY AFTERNOON ALONG COLD FRONT MOVING THROUGH THE ERN DAKOTAS. ALSO...A SEPARATE AREA OF THUNDERSTORMS SHOULD FORM ACROSS SRN/CENTRAL MN/WI BY LATE AFTERNOON AS LOW LEVEL JET STRENGTHENS AND IMPINGES UPON SURFACE BOUNDARY. AIR MASS ACROSS THE TWO AREAS WILL BE MODERATELY UNSTABLE AND DEEP LAYER SHEAR FROM 25-35 KT SHOULD SUPPORT CLUSTERS OF SEVERE MULTICELLS. THE ERN DAKOTA STORMS SHOULD WEAKEN SHORTLY AFTER SUNSET AS THEY MOVE EWD INTO A MORE STABLE BOUNDARY LAYER. THE STORMS OVER SRN/CENTRAL MN/WI MAY REMAIN STRONG UNTIL MID EVENING AS LOW LEVEL JET PROVIDES ADDITIONAL LIFT. HOWEVER... EXPECT THESE STORMS TO WEAKEN THEREAFTER AS THE AIR MASS STABILIZES FROM OUTFLOWS AND A DEEPENING STABLE BOUNDARY LAYER. THE STORMS MAY DEVELOP/SOUTHWARD INTO NRN IA/IL AS THE LOW LEVEL JET VEERS...BUT EXPECT THIS ELEVATED CONVECTION TO REMAIN MOSTLY NON-SEVERE. ...SOUTHWESTERN U.S.... MID/HIGH LEVEL MOISTURE CIRCULATING AROUND UPPER HIGH AND INCREASE IN BOUNDARY LAYER MOISTURE FROM THE SOUTH SUGGESTS SCATTERED THUNDERSTORMS SHOULD ONCE AGAIN DEVELOP ACROSS THE HIGHER TERRAIN OF NRN/ERN AZ DURING THE AFTERNOON. ENELY MID LEVEL WINDS AT 10 TO 15 KT SHOULD CARRY THE STORMS INTO THE DESERT FLOORS WHERE TEMPERATURES WILL BE ABOVE 100F...RESULTING IN VERY STEEP LOW LEVEL LAPSE RATES. THIS SUGGESTS THE POSSIBILITY OF ISOLATED STRONG/SEVERE WIND GUSTS...THOUGH THE SLOW MOTION OF STORMS PRECLUDES A SLIGHT RISK ATTM. ...UPPER TX COAST... AS MID/UPPER LEVEL LOW OVER THE NWRN GULF MOVES SLOWLY NWD AND POSSIBLY INTENSIFIES...LOW AND DEEP LAYER SHEAR PROFILES ARE FORECAST TO STRENGTHEN ACROSS THE REGION BY LATE TUESDAY NIGHT. THOUGH THE AIR MASS WILL BE QUITE WARM AND MOIST...INSTABILITY WILL BE LIMITED. HOWEVER...IF CELLULAR STORMS CAN DEVELOP...SHEAR WOULD SUPPORT SUPERCELLS AND THE VERY SMALL POSSIBILITY OF A TORNADO TOWARD THE END OF THE PERIOD. ..IMY.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 12:39:35 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 08:39:35 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251235 SWODY1 SPC AC 251234 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 AM CDT TUE JUL 25 2006 VALID 251300Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MIDWEST AND WESTERN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF NORTHERN NEW ENGLAND... ...MIDWEST STATES AND WESTERN GREAT LAKES... MORNING WATER VAPOR LOOPS SHOW SERIES OF SHORTWAVE TROUGHS TRACKING EAST-SOUTHEASTWARD ACROSS THE CANADIAN PRAIRIES...THE GREAT LAKES...AND INTO NEW ENGLAND. ONE FEATURE IS CURRENTLY OVER SOUTHEAST MANITOBA AND WILL TRACK INTO MN BY THIS EVENING. RELATIVELY STRONG HEATING IS EXPECTED AHEAD OF THIS SYSTEM FROM THE EASTERN DAKOTAS INTO MN/WI/MI...WHERE DEWPOINTS WELL INTO THE 60S AND STEEP LOW LEVEL LAPSE RATES WILL RESULT IN MLCAPE OVER 1000 J/KG. SEVERAL CLUSTERS OF THUNDERSTORMS ARE LIKELY TO FORM OVER THESE REGIONS THIS AFTERNOON...BOTH ALONG THE FRONT OVER WESTERN MN/EASTERN SD...AND EASTWARD INTO WI/MI IN LOW LEVEL WARM ADVECTION REGIME. FAVORABLE DEEP LAYER VERTICAL SHEAR PROFILES WILL PROMOTE ORGANIZED MULTICELL OR SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. OTHER MORE ISOLATED THUNDERSTORMS ARE LIKELY TO FORM IN PARTS OF NORTHEAST NEB/NORTHWEST IA WHERE HOT SURFACE TEMPERATURES WILL HELP REACH CONVECTIVE TEMPERATURE. THESE STORMS WILL HAVE THE POTENTIAL TO PERSIST INTO THE EVENING AND SPREAD ACROSS MUCH OF IA WITH A RISK OF DAMAGING WINDS. ...NORTHERN NEW ENGLAND... SHORTWAVE TROUGH OVER WESTERN QUEBEC WILL TRACK ACROSS NORTHERN NEW ENGLAND TODAY. RADAR/SATELLITE IMAGERY SHOWS WIDESPREAD CONVECTION OVER NORTHERN ME WHICH WILL LIMIT DAYTIME HEATING. HOWEVER...MODERATE INSTABILITY WILL LIKELY DEVELOP ALONG SOUTHERN PERIPHERY OF PRECIPITATION...HELPING STORMS TO INTENSIFY BY EARLY AFTERNOON. MODEL FORECAST SOUNDINGS SHOW 30-40 KNOT 6KM VERTICAL SHEAR VALUES FAVORABLE FOR A THREAT OF ISOLATED SEVERE THUNDERSTORMS. DAMAGING WINDS AND HAIL WILL BE POSSIBLE IN STRONGER CELLS. ...CENTRAL HIGH PLAINS... PLUME OF RICH MID LEVEL MOISTURE IS EVIDENT IN WATER VAPOR IMAGERY FROM THE FOUR CORNERS REGION INTO NEB. STRONG DAYTIME HEATING IS EXPECTED IN THIS AXIS...ESPECIALLY FROM EASTERN CO INTO NEB. SCATTERED THUNDERSTORMS ARE LIKELY TO FORM OVER THE FOOTHILLS OF CO AND SPREAD EASTWARD INTO THE ADJACENT PLAINS. DEEP...MIXED BOUNDARY LAYER WILL PROMOTE THREAT OF GUSTY WINDS IN STRONGER CELLS. ACTIVITY MAY SPREAD AS FAR EAST AS WESTERN KS BEFORE DIMINISHING LATE TONIGHT. ..HART/TAYLOR.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 16:25:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 12:25:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251622 SWODY1 SPC AC 251620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT TUE JUL 25 2006 VALID 251630Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS NORTH CENTRAL STATES... ...NCENTRAL U.S... SERIES OF S/WV TROUGHS MOVING IN THE WNWLY FLOW FROM SRN CANADA TO NEW ENGLAND. ONE IMPULSE CURRENTLY MOVING ESEWD CANADIAN PRAIRIE PROVINCES REACHING WRN GREAT LAKES BY 12Z WED. SURFACE FEATURES OF IMPORTANCE ARE THE TROUGH LOCATED FROM ERN SD SWWD INTO NWRN KS AND A WEAK COOL FRONT NOW PUSHING EWD ACROSS WRN ND INTO ERN WY AHEAD OF THE S/WV TROUGH. A WARM AND POTENTIALLY MDT TO VERY UNSTABLE AIR MASS IS IN PLACE ACROSS MUCH OF THE NCENTRAL U.S. WITH DEWPOINTS IN THE MID 60S TO NEAR 70F COMMON FROM ERN DAKOTAS/NEB TO WRN GREAT LAKES. WITH STRONG DAYTIME HEATING MUCH OF AREA...THUNDERSTORMS WILL DEVELOP VICINITY OF BOTH THE FRONTAL SYSTEM AND SURFACE TROUGH BY MID AFTERNOON. WITH MLCAPES RANGING UPWARDS TO 2500 J/KG AND LAPSE RATES GENERALLY 7C/KM OR GREATER...LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. IDENTIFYING THE MOST FAVORABLE REGION FOR THE HIGHER SEVERE POTENTIAL IS DIFFICULT WITH THE GENERALLY WEAK LOW LEVEL FLOW AND CONVERGENCE OVER MUCH OF THE NCENTRAL STATES. HOWEVER AS THE UPPER TROUGH APPROACHES...CONDITIONS WOULD FAVOR MORE ORGANIZED SEVERE POTENTIAL DEVELOPING BY LATE THIS AFTERNOON ACROSS SRN MN/NRN IA IN AREA OF POOLED MOISTURE/INSTABILITY. AN MCS COULD THEN PROPAGATE INTO WI THIS EVENING WITH ASSOCIATED SEVERE THREAT. ...NEW ENGLAND... BAND OF CLOUDINESS/PCPN THAT HAS SPREAD EWD ACROSS NRN NH/VT AND MAINE...EXPECTED TO LIMIT HEATING/DESTABILIZATION THIS AFTERNOON IN AREA OF EARLIER SLIGHT RISK. S/WV TROUGH SWINGING EWD ACROSS QUEBEC HAS ENHANCED SHEAR PROFILES ACROSS MUCH OF NEW ENGLAND. THINNING OF CLOUDS WILL ALLOW SOME HEATING THIS AFTERNOON NRN NEW ENGLAND. HOWEVER STILL EXPECT INSUFFICIENT INSTABILITY TO DEVELOP TO SUPPORT ORGANIZED SEVERE THREAT. A FEW STRONG/SEVERE STORMS ARE LIKELY...PARTICULARLY ACROSS WRN/NRN NY EWD ALONG THE SRN EDGE OF CURRENT CLOUDINESS. ...SWRN U.S... GULF SURGE UNDERWAY WITH VERY MOIST AIR MASS SPREADING NWD ACROSS SERN CA DESERTS AND MUCH OF SRN AZ. WITH STEEP LAPSE RATES IN PLACE THE LOW LEVEL MOISTURE INCREASE SHOULD RESULT IN A SUBSTANTIALLY MORE UNSTABLE AIR MASS THIS AFTERNOON S OF MOGOLLON RIM WWD TO SRN CA MTS. WITH MLCAPES OVER THE DESERTS RISING TO WELL ABOVE 2000 J/KG THE PRIMARY QUESTION REGARDING A SEVERE THREAT IS STORM INITIATION. STEERING FLOW IS GENERALLY WEAK ELY TO THE S OF 4 CORNERS UPPER HIGH. STORMS WILL DEVELOP OVER HIGHER TERRAIN DURING AFTERNOON AND SLOWLY PROPAGATE TOWARD LOWER ELEVATIONS. IF THE STEERING FLOW WAS STRONGER WOULD CONSIDER A SLIGHT RISK...BUT FOR NOW WILL JUST ADD LOW PROBABILITIES OF BOTH WIND AND HAIL. ..HALES/JEWELL.. 07/25/2006  From swody1 at goshenarc.org Tue Jul 25 19:59:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 15:59:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251955 SWODY1 SPC AC 251954 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0254 PM CDT TUE JUL 25 2006 VALID 252000Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MIDWEST.... ...SYNOPSIS... LATEST WATER VAPOR IMAGERY DEPICTS VERY WELL MID/UPPER LEVEL SHORTWAVE TROUGH MOVING SEWD ACROSS MANITOBA AND SERN SASKATCHEWAN. THIS WILL CONTINUE TO MOVE SEWD THE REMAINDER OF THE PERIOD AS STRONG MID/UPPER LEVEL RIDGE COVERS THE SWRN QUARTER OF THE U.S. IN ADDITION...MID/UPPER LEVEL TROUGH WILL CONTINUE TO MOVE NWD FROM THE NERN MEXICAN COAST INTO THE MIDDLE TX COAST REGION. ...UPPER MIDWEST... LATEST SURFACE ANALYSIS SHOWS WEAK COLD FRONTAL BOUNDARY EXTENDING FROM EXTREME NWRN MN TO A LOW OVER THE CENTRAL ND/SD BORDER...THEN NWWD THRU SERN AND N CENTRAL MT. THIS IS DEVELOPING INTO SOMEWHAT OF A COMPLEX SITUATION AS THERE HAVE BEEN SHOWERS/ISOLATED THUNDERSTORMS OVER PARTS OF THE MIDDLE MO VALLEY THUS FAR AND CONVECTION HAS FIRED ALONG THE FRONTAL BOUNDARY OVER NWRN MN INTO EAST CENTRAL ND. THIS ACTIVITY WILL BE MOVING INTO AN AXIS WITH VERY UNSTABLE AIR WHERE MLCAPES RANGE BETWEEN 2000 AND 2500 J/KG FROM NERN SD SEWD INTO SWRN WI AND NRN IL. IT LOOKS LIKE THERE ARE TWO SITUATIONS WHERE SEVERE WEATHER CAN DEVELOP THRU EARLY TONIGHT ACROSS THE UPPER MIDWEST. FIRST...EXPECT FRONTAL BOUNDARY DEVELOPMENT TO CONTINUE AND INTENSIFY AS IT MOVES SEWD FEEDING ON THE THERMODYNAMICS FROM SD INTO IL. SECOND WILL BE THE BOUNDARIES IN THE VICINITY OF ELEVATED CONVECTION OVER SERN SD/ERN NEB/WRN IA. STORMS COULD REINTENSIFY OVER IA WHERE MLCAPE HAS REACHED 3000 J/KG ALLOWING BOUNDARIES TO BE PRESENT AHEAD OF APPROACHING COLD FRONT LATER THIS EVENING AND TONIGHT. THUS...WITH BOTH SCENARIOS LOOKS LIKE MAIN THREAT WILL BE STRONG DAMAGING WINDS AND SOME HAIL ACROSS THE REGION. ...LOWER GREAT LAKES... LAKE BREEZE THUNDERSTORMS HAVE DEVELOPED FROM SWRN NY STATE SWWD INTO NERN OH. ACTIVITY IS WITHIN AREA WHERE MLCAPES ARE AROUND 1000 J/KG AHEAD OF WEAK VORTICITY MAX MOVING EWD OVER EXTREME SERN ONTARIO JUST ALONG THE NERN SHORES OF LAKE ERIE. MID LEVEL LAPSE RATES ARE AROUND 7C/KM WHICH WOULD BE SUPPORTIVE OF GUSTY WINDS WITH THUNDERSTORM ACTIVITY. WOULD ANTICIPATE MORE SCATTERED STRONG THUNDERSTORMS TO DEVELOP IN CU FIELD THAT IS EXTENDING NEWD TOWARDS NRN VERMONT AGAIN WITH THE THREAT BEING MAINLY GUSTY WINDS. ...PARTS OF THE DESERT SOUTHWEST... SEE MESOSCALE DISCUSSION 1624 FOR THE LATEST INFORMATION ON SEVERE THUNDERSTORM POTENTIAL. ..MCCARTHY.. 07/25/2006  From swody1 at goshenarc.org Wed Jul 26 01:05:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 25 Jul 2006 21:05:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260100 SWODY1 SPC AC 260058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT TUE JUL 25 2006 VALID 260100Z - 261200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE UPPER MIDWEST/WESTERN GREAT LAKES REGION... ...UPPER MIDWEST AND WESTERN GREAT LAKES... WATER VAPOR IMAGERY THIS EVENING SHOWS ONE SHORTWAVE TROUGH IS MOVING THROUGH WRN MN/NWRN IA...WHILE A STRONGER SYSTEM WAS DROPPING SEWD THROUGH ERN ND. A COLD FRONT AND A BAND OF THUNDERSTORMS...ASSOCIATED WITH THE ERN ND SYSTEM...WERE MOVING SEWD THROUGH CENTRAL MN WWD INTO SERN SD. MODERATE INSTABILITY AND FORCING WILL RESULT IN A FEW SEVERE STORMS THROUGH MID EVENING... REFERENCE WW 642. LARGE AREA OF MID/HIGH CLOUDS WERE LOCATED AHEAD OF THE MN SHORTWAVE TROUGH FROM ERN NEB ACROSS WRN/NRN IA INTO SWRN WI. SURFACE BASED AND MORE INTENSE CONVECTION DEVELOPED IN THE WARMER AIR MASS TO THE EAST OF THE DENSE CLOUDS IN ERN IA. STORMS ARE EXPECTED TO CONGEAL INTO A CLUSTER/LINE WITH THE RESULTANT COLD POOL LIKELY TO INCREASE THE SEVERE WIND THREAT AS THE LOW LEVEL JET STRENGTHENS OVERNIGHT AND PUSHES THE STORMS EWD INTO NRN IL... REFERENCE WW 644. OTHER STRONG/SEVERE STORMS IN NRN WI AND THE U.P. SHOULD CONTINUE MOVING NEWD THROUGH THE EVENING WITH A THREAT FOR HAIL AND MARGINALLY SEVERE WIND GUSTS...REF 643 DESPITE EXTENSIVE MID/HIGH CLOUDS...AIR MASS ACROSS ERN NEB/WRN IA REMAINS MODERATELY UNSTABLE. AS LOW LEVEL JET INCREASES OVERNIGHT ...ELEVATED STORMS ARE POSSIBLE. CONVECTIVE INITIATION IN THIS AREA IS UNCERTAIN...BUT THE AMOUNT OF INSTABILITY AND VEERING WIND PROFILES IN THE LOWER 3 KM WOULD SUPPORT SEVERE STORMS...REF MCD 1626. ...NY... THUNDERSTORMS WERE INITIATED ALONG THE LAKE BREEZE EARLIER TODAY AND HAVE REMAINED STRONG/SEVERE INTO THE EARLY EVENING HOURS. HOWEVER BUF AND ALY EVENING SOUNDINGS SHOW UPDRAFT ROOTS WILL BECOME DECOUPLED FROM THE BOUNDARY LAYER WITH A FEW MORE DEGREES OF COOLING...SO STORMS SHOULD WEAKEN BELOW SEVERE CRITERIA SHORTLY. ...DESERT SOUTHWEST... BAND OF STORMS WEST OF TUS ARE IN A LITTLE STRONGER MID LEVEL ELY FLOW AND WITH MODERATE INSTABILITY...ISOLATED SEVERE HAIL/WINDS ARE EXPECTED WITH THIS CONVECTION AS IT MOVES WSWWD. ANOTHER BAND OF STORMS WAS MOVING SLOWLY SWD OFF THE RIM AND EXTENDED FROM NORTH OF IGM TO EAST OF PRC. WHILE MLCAPE VALUES ABOVE 2000 J/KG WOULD SUPPORT A SEVERE THREAT...THE WEAK WINDS ALOFT AND SLOW STORM MOTION SUGGESTS HAIL/WIND WITH THESE STORMS SHOULD BE LOCALIZED. ..IMY.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 05:23:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 01:23:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260519 SWODY1 SPC AC 260518 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1218 AM CDT WED JUL 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN GREAT LAKES SWWD INTO THE MID MS VALLEY REGION... ...SYNOPSIS... BROAD UPPER TROUGH WILL EXTEND FROM THE NRN ROCKIES EWD INTO THE MID/UPPER MS VALLEY AND THEN NEWD INTO NEW ENGLAND...WHILE A RIDGE COVERS MOST OF THE COUNTRY. A WELL DEFINED SHORTWAVE TROUGH WITHIN THIS BROAD TROUGH...CURRENTLY LOCATED IN NRN MN...WILL MOVE SEWD THROUGH THE GREAT LAKES AREA TODAY. WEAK FRONTAL SYSTEM BY LATE AFTERNOON WILL EXTEND FROM THE WRN GREAT LAKES SWWD INTO SRN IA/SRN NEB...WITH A SURFACE TROUGH FORECAST TO STRETCH FROM NERN MO SWWD INTO SRN KS. AN UPPER TROUGH...WHICH HAS BEEN SITUATED OVER THE WRN GULF THE PAST FEW DAYS...IS PROGGED TO LIFT NWD INTO SERN TX DURING THE DAY WEDNESDAY. ...ERN GREAT LAKES AREA AND MIDDLE MS VALLEY REGION... UNCERTAINTIES EXIST CONCERNING CONVECTIVE INITIATION POTENTIAL AND EVOLUTION FOR SEVERE WEATHER. STRONGEST FORCING FOR CONVECTION WILL BE ASSOCIATED WITH SHORTWAVE TROUGH THAT IS EXPECTED TO BE LOCATED OVER WI AT 18Z AND MOVE EAST OF LOWER MI AFTER 00Z. DEEP LAYER SHEAR WILL BE FAVORABLE FOR SEVERE STORMS...BUT INSTABILITY IS LIKELY TO BE WEAK AS WIDESPREAD CONVECTION/CLOUDS OVERSPREAD LOWER MI THIS MORNING. IF SOME HEATING CAN OCCUR FROM LATE MORNING THROUGH EARLY AFTERNOON PRIOR TO THE TROUGH PASSAGE...A FEW STORMS WITH WIND DAMAGE WOULD BE POSSIBLE. STORMS ARE ALSO EXPECTED TO BE ONGOING AT DAYBREAK ACROSS EXTREME ERN IA ON THE NOSE OF THE LOW LEVEL JET. IF REMNANT CONVECTION/ OUTFLOW BOUNDARY FROM THESE STORMS CAN BE MAINTAINED EWD THROUGH MID MORNING...THE STORMS WOULD LIKELY INTENSIFY AS THEY MOVE INTO A WARMING/DESTABILIZING AIR MASS. WIND AND HAIL WOULD BE POSSIBLE WITH THESE STORMS. OTHER STORMS MAY DEVELOP LATE AFTERNOON/EVENING ACROSS SRN IA/NRN MO WHERE THE AIR MASS WILL BE CAPPED THROUGH MUCH OF THE DAY...ALLOWING THE ENVIRONMENT TO BECOME STRONGLY UNSTABLE WITH MLCAPES NEAR 3000 J/KG. THE WARM TEMPERATURES ALOFT WOULD INHIBIT LARGE HAIL. TEMPERATURES NEAR 100F...30 DEGREE SPREADS...AND STEEP MID LEVEL LAPSE RATES WOULD SUPPORT A DAMAGING WIND THREAT. OTHER HIGH BASED STORMS MAY ALSO DEVELOP SWWD ALONG THE SURFACE TROUGH INTO PORTIONS OF ERN/SRN KS. ...ERN TX AND LA... LATEST ETA/GFS MODELS BOTH LIFT GULF TROUGH NWD TODAY WITH STRONGEST WINDS LOCATED ACROSS FAR ERN TX AND LA. MOIST ADIABATIC LAPSE RATES AND CONSIDERABLE CLOUDS WILL LIMIT THE SEVERE POTENTIAL. HOWEVER...STORMS THAT DEVELOP AND MOVE NWD INTO AREAS THAT HAVE WARMED INTO THE 90S WILL ENCOUNTER A MODERATELY UNSTABLE AIR MASS AND A POTENTIAL FOR STRONG/SEVERE WIND GUSTS. ...SRN AZ... DESPITE WEAK WINDS ALOFT...STORMS ORGANIZED LATE TUESDAY AND THE DEVELOPMENT OF A STRONG COLD POOL PUSHED STRONG/SEVERE STORMS SWD THROUGH SRN AZ. MOISTURE SURGE FROM TROPICAL STORM EMILIA WILL MAINTAIN A MOIST BOUNDARY LAYER AND IF SUFFICIENT HEATING OCCURS AFTER CLOUDS CLEAR IN THE MORNING...ORGANIZED SEVERE STORMS ARE POSSIBLE AGAIN. HOWEVER...SOME CONCERN THAT CONVECTIVE OVERTURNING THIS EVENING MAY RESULT IN WEAKER CONVECTION...SO ONLY LOW PROBABILITIES FORECAST ATTM. ...ERN PA NEWD INTO NRN NEW ENGLAND... WEAK TROUGH IS FORECAST ACROSS THE AREA AND MODERATE INSTABILITY ALONG WITH WEAK CAPPING SHOULD RESULT IN SCATTERED AFTERNOON THUNDERSTORMS. A FEW STRONG WIND GUSTS/HAIL EVENTS ARE POSSIBLE GIVEN THE AMOUNT OF INSTABILITY...THOUGH THE WEAK WIND FIELDS/SHEAR SUGGEST THAT THE THREAT IS LOW. ..IMY/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 06:22:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 02:22:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260619 SWODY1 SPC AC 260617 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0117 AM CDT WED JUL 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN GREAT LAKES SWWD INTO THE MID MS VALLEY REGION... ...SYNOPSIS... BROAD UPPER TROUGH WILL EXTEND FROM THE NRN ROCKIES EWD INTO THE MID/UPPER MS VALLEY AND THEN NEWD INTO NEW ENGLAND...WHILE A RIDGE COVERS MOST OF THE COUNTRY. A WELL DEFINED SHORTWAVE TROUGH WITHIN THIS BROAD TROUGH...CURRENTLY LOCATED IN NRN MN...WILL MOVE SEWD THROUGH THE GREAT LAKES AREA TODAY. WEAK FRONTAL SYSTEM BY LATE AFTERNOON WILL EXTEND FROM THE WRN GREAT LAKES SWWD INTO SRN IA/SRN NEB...WITH A SURFACE TROUGH FORECAST TO STRETCH FROM NERN MO SWWD INTO SRN KS. AN UPPER TROUGH...WHICH HAS BEEN SITUATED OVER THE WRN GULF THE PAST FEW DAYS...IS PROGGED TO LIFT NWD INTO SERN TX DURING THE DAY WEDNESDAY. ...ERN GREAT LAKES AREA AND MIDDLE MS VALLEY REGION... UNCERTAINTIES EXIST CONCERNING CONVECTIVE INITIATION POTENTIAL AND EVOLUTION FOR SEVERE WEATHER. STRONGEST FORCING FOR CONVECTION WILL BE ASSOCIATED WITH SHORTWAVE TROUGH THAT IS EXPECTED TO BE LOCATED OVER WI AT 18Z AND MOVE EAST OF LOWER MI AFTER 00Z. DEEP LAYER SHEAR WILL BE FAVORABLE FOR SEVERE STORMS...BUT INSTABILITY IS LIKELY TO BE WEAK AS WIDESPREAD CONVECTION/CLOUDS OVERSPREAD LOWER MI THIS MORNING. IF SOME HEATING CAN OCCUR FROM LATE MORNING THROUGH EARLY AFTERNOON PRIOR TO THE TROUGH PASSAGE...A FEW STORMS WITH WIND DAMAGE WOULD BE POSSIBLE. STORMS ARE ALSO EXPECTED TO BE ONGOING AT DAYBREAK ACROSS EXTREME ERN IA ON THE NOSE OF THE LOW LEVEL JET. IF REMNANT CONVECTION/ OUTFLOW BOUNDARY FROM THESE STORMS CAN BE MAINTAINED EWD THROUGH MID MORNING...THE STORMS WOULD LIKELY INTENSIFY AS THEY MOVE INTO A WARMING/DESTABILIZING AIR MASS. WIND AND HAIL WOULD BE POSSIBLE WITH THESE STORMS. OTHER STORMS MAY DEVELOP LATE AFTERNOON/EVENING ACROSS SRN IA/NRN MO WHERE THE AIR MASS WILL BE CAPPED THROUGH MUCH OF THE DAY...ALLOWING THE ENVIRONMENT TO BECOME STRONGLY UNSTABLE WITH MLCAPES NEAR 3000 J/KG. THE WARM TEMPERATURES ALOFT WOULD INHIBIT LARGE HAIL. TEMPERATURES NEAR 100F...30 DEGREE SPREADS...AND STEEP MID LEVEL LAPSE RATES WOULD SUPPORT A DAMAGING WIND THREAT. OTHER HIGH BASED STORMS MAY ALSO DEVELOP SWWD ALONG THE SURFACE TROUGH INTO PORTIONS OF ERN/SRN KS. ...ERN TX AND LA... LATEST ETA/GFS MODELS BOTH LIFT GULF TROUGH NWD TODAY WITH STRONGEST WINDS LOCATED ACROSS FAR ERN TX AND LA. MOIST ADIABATIC LAPSE RATES AND CONSIDERABLE CLOUDS WILL LIMIT THE SEVERE POTENTIAL. HOWEVER...STORMS THAT DEVELOP AND MOVE NWD INTO AREAS THAT HAVE WARMED INTO THE 90S WILL ENCOUNTER A MODERATELY UNSTABLE AIR MASS AND A POTENTIAL FOR STRONG/SEVERE WIND GUSTS. ...SRN AZ... DESPITE WEAK WINDS ALOFT...STORMS ORGANIZED LATE TUESDAY AND THE DEVELOPMENT OF A STRONG COLD POOL PUSHED STRONG/SEVERE STORMS SWD THROUGH SRN AZ. MOISTURE SURGE FROM TROPICAL STORM EMILIA WILL MAINTAIN A MOIST BOUNDARY LAYER AND IF SUFFICIENT HEATING OCCURS AFTER CLOUDS CLEAR IN THE MORNING...ORGANIZED SEVERE STORMS ARE POSSIBLE AGAIN. HOWEVER...SOME CONCERN THAT CONVECTIVE OVERTURNING THIS EVENING MAY RESULT IN WEAKER CONVECTION...SO ONLY LOW PROBABILITIES FORECAST ATTM. ...ERN PA NEWD INTO NRN NEW ENGLAND... WEAK TROUGH IS FORECAST ACROSS THE AREA AND MODERATE INSTABILITY ALONG WITH WEAK CAPPING SHOULD RESULT IN SCATTERED AFTERNOON THUNDERSTORMS. A FEW STRONG WIND GUSTS/HAIL EVENTS ARE POSSIBLE GIVEN THE AMOUNT OF INSTABILITY...THOUGH THE WEAK WIND FIELDS/SHEAR SUGGEST THAT THE THREAT IS LOW. ..IMY/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 12:38:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 08:38:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261233 SWODY1 SPC AC 261232 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0732 AM CDT WED JUL 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS VALLEY ACROSS THE GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF EAST TX AND WESTERN LA... ...MID MS VALLEY AND GREAT LAKES REGION... MORNING WATER VAPOR IMAGERY SHOWS VIGOROUS SHORTWAVE TROUGH DIGGING SOUTHEASTWARD ACROSS MN/WI INTO THE GREAT LAKES REGION. THIS FEATURE HAS MAINTAINED AN AREA OF WEAK CONVECTION OVER IA/IL/MO OVERNIGHT. STORMS ARE LIKELY TO WEAKEN THIS MORNING...BEFORE INCREASING AGAIN THIS AFTERNOON FROM CENTRAL IL INTO IND. STRONG HEATING AHEAD OF ACTIVITY WILL RESULT IN MLCAPE VALUES OVER 2000 J/KG. MODERATELY STRONG WESTERLY FLOW ALOFT WILL ALSO HELP TO ORGANIZE STORMS...WITH INTENSE MULTICELLS CAPABLE OF DAMAGING WINDS AND HAIL. ACTIVITY MAY SPREAD INTO WESTERN OH DURING THE EVENING BEFORE WEAKENING. FARTHER NORTH...MAIN SURFACE FRONT/CONVERGENCE AXIS WILL STRETCH FROM WI INTO UPPER MI BY MID AFTERNOON. RATHER COOL TEMPERATURES ALOFT AND STRONG HEATING WILL HELP TO DESTABILIZE THIS AREA...LEADING TO SCATTERED THUNDERSTORMS. ACTIVITY SHOULD SPREAD ACROSS LOWER MI DURING THE LATE AFTERNOON WITH A RISK OF HAIL AND DAMAGING WINDS. ...AR/TX... UPPER LEVEL LOW IS MOVING SLOWLY NORTHWARD NEAR THE UPPER TX GULF COAST. LOW LEVEL WIND FIELDS HAVE BECOME RATHER STRONG ON EAST SIDE OF LOW...WITH 40-50 KNOT SOUTHERLY 850MB WINDS FORECAST THIS AFTERNOON INTO PARTS OF EAST TX/WESTERN LA. A VERY MOIST AIR MASS IS IN PLACE WITH DEWPOINTS IN THE LOWER 70S...LEADING TO SETUP SIMILAR TO A WEAK TROPICAL SYSTEM. ISOLATED CELLS IN THIS REGION HAVE SHOWN LOW LEVEL ROTATION THIS MORNING...AND THREAT SHOULD CONTINUE THROUGH THE DAY AS DIURNAL HEATING ENHANCES INSTABILITY. ...NY/PA INTO NEW ENGLAND... ISOLATED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON ACROSS PARTS OF THE NORTHEAST U.S...WHERE FULL SUNSHINE AND DEWPOINTS WELL INTO THE 60S ARE EXPECTED. WARM TEMPERATURES ALOFT AND WEAK VERTICAL SHEAR WILL TEND TO LIMIT UPDRAFT INTENSITY. HOWEVER...SOME DRY AIR ALOFT AND STEEP LOW LEVEL LAPSE RATES WILL PROMOTE A RISK OF GUSTY WINDS IN STRONGEST CELLS. ...DESERT SOUTHWEST... GULF SURGE CONTINUES TODAY AS DEWPOINTS RISE THROUGH THE 60S OVER SOUTHERN/WESTERN AZ. OVERNIGHT CONVECTION IS WEAKENING RAPIDLY...WHICH SHOULD ALLOW STRONG DESTABILIZATION AGAIN THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON OVER THE MOUNTAINS OF SOUTHWEST NM/EASTERN AZ AND PROPAGATE WESTWARD. UPGRADE TO SLIGHT RISK MAY BE REQUIRED THIS AFTERNOON AS AREAS OF STRONG HEATING BECOME MORE APPARENT AND LOW LEVEL MOISTURE TRENDS CAN BE MONITORED. ..HART/TAYLOR.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 16:22:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 12:22:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261617 SWODY1 SPC AC 261615 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1115 AM CDT WED JUL 26 2006 VALID 261630Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS MID MS VALLEY TO GREAT LAKES REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ERN TX AND LA... ...SYNOPSIS... AS UPPER HIGH IN THE W HAS GRADUALLY WEAKENED A WNWLY FLOW WITH SEVERAL EMBEDDED S/WV TROUGHS PREVAILS ACROSS THE NRN TIER OF THE CONUS. THE STRONGEST IMPULSE CURRENTLY MOVING EWD ACROSS THE UPPER GREAT LAKES AND OH VALLEY. A RATHER WEAK SURFACE FRONTAL ZONE EXTENDS FROM UPPER MI SWWD ACROSS SRN MN TO NERN CO. A TROPICAL LOW PRESSURE CENTER HAS MOVED INLAND FROM NWRN GULF TO A POSITION NW OF VCT ATTM. A MDTLY STRONG SLY FLOW OF TROPICAL AIR CONTINUES TO STREAM INLAND ACROSS ERN TX/WRN LA. ...MID MS VALLEY AND GREAT LAKES REGION... MUCH OF THREAT AREA IS CURRENTLY CLOUD COVERED WHICH WILL DELAY SEVERE THUNDERSTORM DEVELOPMENT UNTIL LATER THIS AFTERNOON. STRONGER BAND OF DEEP LAYER SHEAR ASSOCIATED WITH THE UPPER S/WV TROUGH MOVING ACROSS THIS AREA WILL SUPPORT MULTICELL THUNDERSTORMS ONCE AIR MASS CAN DESTABILIZE WITH AFTERNOON HEATING. THE AIR MASS IS VERY MOIST ACROSS THIS REGION AND WILL JUST REQUIRE SUFFICIENT HEATING TO WEAKEN CIN TO ALLOW SURFACE BASED STORMS TO DEVELOP. SURFACE CONVERGENCE IS RATHER WEAK BUT THE FRONTAL ZONE AS WELL AS OUTFLOW BOUNDARIES FROM OVERNIGHT CONVECTION SHOULD FOCUS INITIATION BY MID/LATE AFTERNOON. PRIMARY THREAT WILL BE LOCAL DAMAGING WIND AND MARGINALLY SEVERE HAIL GIVEN THE MULTICELL NATURE OF THE CONVECTION. ...ERN TX/LA... WITH THE MODELS INDICATING THE LOW LEVEL CIRCULATION NOW ONSHORE SCENTRAL TX CONTINUING A SLOW NNEWD MOVEMENT ACROSS ERN TX THIS FORECAST PERIOD...A THREAT OF TROPICAL SUPERCELLS WILL CONTINUE AND SHIFT INLAND AS WELL. 20-30KT OF SFC-1KM SHEAR AND HELICITIES UPWARDS TO 200 M2/S2 EXPECTED TO MAINTAIN A THREAT OF SUPERCELLS AND ISOLATED TORNADOES. THE CURRENT THREAT AREA SERN TX/SWRN LA COAST WILL SHIFT INLAND THIS AFTERNOON IN CONCERT WITH THE LOW MOVEMENT. ...SWRN U.S... TUESDAYS GULF SURGE FOLLOWED BY ACTIVE OVERNIGHT CONVECTION SRN AZ HAS TRANFORMED MUCH OF THE AZ DESERTS AIR MASS INTO A VERY MOIST AND MODERATELY UNSTABLE ENVIRONMENT. THE STABILIZING EFFECT OF THE NIGHTTIME ACTIVITY WILL REDUCE SOMEWHAT THE THREAT OF SEVERE THUNDERSTORMS TODAY. HOWEVER WITH THE MID CLOUD COVER EVAPORATING...HEATING EXPECTED TO BE SUFFICIENT TO ALLOW MLCAPES TO CLIMB BACK TO NEAR 2000 J/KG BY LATER THIS AFTERNOON. STEERING FLOW IS GENERALLY LESS THAN 10KT. STORMS WILL INITIATE OVER HIGHER TERRAIN AND SLOWLY DEVELOP INTO LOWER ELEVATIONS LATER THIS AFTERNOON/EVENING. STILL A THREAT OF ISOLATED WIND/HAIL...HOWEVER WITH SOME DECREASE IN LAPSE RATES FROM THE PREVIOUS DAYS...ORGANIZED SEVERE THREAT IS NOT ANTICIPATED. ...INTERIOR NERN U.S... NEARLY FULL HEATING COUPLED WITH A MOIST AIR MASS WILL SUPPORT THUNDERSTORM DEVELOPMENT OVER HIGHER TERRAIN BY MID AFTERNOON FROM PA NEWD ACROSS NEW ENGLAND. WITH SHEAR GENERALLY LESS THAN 15KT...PULSE STORMS SHOULD BE THE PREDOMINANT MODE...WITH LOCAL GUSTY WINDS AND MARGINALLY SEVERE HAIL. ...SERN COASTAL AREAS... FULL HEATING AND A MOIST AIR MASS WILL LEAD TO MLCAPES TO ABOVE 2000 J/KG. SUFFICIENT SHEAR UP TO 20KT AND STEEP LOW LEVEL LAPSE RATES...SHOULD RESULT IN A FEW STRONG/SEVERE STORMS THIS AFTERNOON. PRIMARY AREA OF DEVELOPMENT SHOULD BE VICINITY OF SEA BREEZE FRONT COASTAL SC. ..HALES/JEWELL.. 07/26/2006  From swody1 at goshenarc.org Wed Jul 26 19:59:09 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 15:59:09 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261955 SWODY1 SPC AC 261953 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0253 PM CDT WED JUL 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN LOWER MI INTO THE MID MS/LOWER MO RIVER VALLEYS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF ERN TX INTO WRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PART OF THE CENTRAL HIGH PLAINS... ...CENTRAL GREAT LAKES ACROSS THE MID MS/LOWER MO RIVER VALLEYS... SHORTWAVE TROUGH IS WELL DEFINED ON WV IMAGERY THIS AFTERNOON MOVING ACROSS THE CENTRAL GREAT LAKES. SURFACE LOW IS EXPECTED TO REMAIN NORTH OF THE GREAT LAKES...WITH COLD FRONT /NOW EXTENDING SEWD FROM NERN WI INTO NRN IA/ SHIFTING SSEWD THROUGH THE REST OF THE PERIOD. CLOUDS HAVE REMAINED EXTENSIVE ACROSS MUCH OF LOWER MI TODAY ASSOCIATED WITH THIS FEATURE AND HAVE GREATLY LIMITED INSTABILITY AHEAD OF THE FRONT OVER MUCH OF THE CENTRAL GREAT LAKES. EXCEPTION IS WITHIN STRONG SUBSIDENT REGION OVER ERN/SRN WI AHEAD OF FRONT WHERE AN ISOLATED THUNDERSTORM MAY OCCUR. HOWEVER THIS SUBSIDENCE WILL LIKELY LIMIT CONVECTIVE POTENTIAL IN WAKE OF MID LEVEL TROUGH. APPEARS SEVERE THREAT MAY BE A BIT HIGHER FROM SERN LOWER MI INTO PORTIONS OF THE CENTRAL PLAINS WHERE RICH BOUNDARY LAYER MOISTURE IS SUPPORTING MODERATE TO STRONG INSTABILITY AHEAD OF MID LEVEL TROUGH AND ITS ASSOCIATED SURFACE COLD FRONT. THIS IS ESPECIALLY TRUE INTO THE LOWER/MID MO RIVER VALLEY WHERE MLCAPE IS NOW OVER 3000 J/KG. EFFECTIVE SHEAR FROM 25-35 KT ACROSS THE REGION WILL SUPPORT ORGANIZED LINES/CLUSTERS AND A RISK OF LARGE HAIL/DAMAGING WINDS AS STORMS INCREASE AND SPREAD ESEWD THROUGH THE EVENING. ...CENTRAL HIGH PLAINS... STORMS CONTINUE TO INCREASE OVER PORTIONS OF SRN WY AND NRN/CENTRAL CO AHEAD OF TAIL END OF SHORTWAVE TROUGH NOW OVERSPREADING THE NRN ROCKIES/HIGH PLAINS. ADDITIONAL INCREASING CU ARE EVIDENT ALONG STATIONARY SURFACE BOUNDARY INTO WRN NEB. 4-KM NMM WRF AND 18Z RUC CONTINUE TO DEVELOP SCATTERED CONVECTION AHEAD OF FEATURE MOVING ACROSS THE CENTRAL HIGH PLAINS THIS AFTERNOON/EVENING. GIVEN STRONG HEATING/STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR...STORMS MAY INCREASE/ORGANIZE THROUGH THE EARLY TO MID EVENING ESEWD ACROSS MUCH OF WRN NEB. ...SOUTHEAST TX/SWRN LA... APPEARS SEVERE THREAT HAS BEEN HINDERED TO THIS POINT BY EXTENSIVE CLOUDS/CONVECTION AND RESULTANT WEAK INSTABILITY. HOWEVER...LATEST RUC MAINTAINS FORECAST OF 30-40 KT SLY H85 LLJ THROUGH THE EVENING/OVERNIGHT AS TROPICAL IMPULSE SPREADS NWD ACROSS SERN TX. THIS MIGHT SUPPORT AN ISOLATED...BRIEF TORNADO AS 0-1 KM SHEAR HOLDS AROUND 20 KT /0-1 KM SRH OF 100 M2 S-2/ AND LCLS REMAIN QUITE LOW GIVEN MID 70F SURFACE DEW POINTS. ...SRN AZ INTO THE CO RIVER VALLEY... CONVECTIVE DEBRIS HAS ALL BUT CLEARED OVER MUCH OF THE REGION THIS AFTERNOON...AND WILL ALLOW MODERATE INSTABILITY TO AGAIN DEVELOP. THUNDERSTORMS CONTINUE TO INCREASE OVER HIGHER TERRAIN OVER SWRN NM AND FAR ERN AZ...AS WELL AS JUST NW OF LAS. EXPECT FURTHER DEVELOPMENT WILL OCCUR THIS AFTERNOON/EVENING. FLOW REMAINS RATHER WEAK...THOUGH 10-15 KT H7 WINDS SHOULD BE SUFFICIENT FOR SLOW MOVEMENT OVER LOWER ELEVATIONS THROUGH THE EVENING WITH THREATS OF HAIL AND BRIEF SEVERE GUSTS WITH STRONGER CORES. ...NORTHEAST... MID LEVEL LAPSE RATES AND DEEP LAYER SHEAR REMAIN QUITE WEAK ACROSS THIS REGION THIS AFTERNOON...DESPITE PRESENCE OF MODERATE INSTABILITY AND NEAR 70 SURFACE DEW POINTS. THEREFORE...EXPECT ANY SEVERE STORM WILL REMAIN BRIEF/MARGINAL INTO THE EARLY EVENING. ..EVANS.. 07/26/2006  From swody1 at goshenarc.org Thu Jul 27 01:04:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 21:04:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270100 SWODY1 SPC AC 270057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT WED JUL 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS EWD INTO THE LOWER OH VALLEY... ...MID MS AND LOWER OHIO VALLEYS... ALTHOUGH SHORTWAVE TROUGH HAS MOVED EAST OF THE AREA...CONVERGENCE AND HEATING WAS ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG SURFACE TROUGH THAT EXTENDED FROM SRN LOWER MI SWWD TO NEAR THE MO/IA BORDER. STRONGEST STORMS WERE LOCATED ACROSS CENTRAL IL WHERE MODERATE TO STRONG INSTABILITY WAS PRESENT WITH MARGINALLY FAVORABLE DEEP LAYER SHEAR FOR SUPERCELLS...REFERENCE WW 646. THESE STORMS SHOULD SPREAD ENEWD INTO IND THIS EVENING...THOUGH THE INSTABILITY IS WEAKER EAST OF IL AND THE SEVERE THREAT SHOULD GRADUALLY DIMINISH OVERNIGHT. AS LOW LEVEL JET STRENGTHENS FROM SERN OK INTO CENTRAL MO THIS EVENING...STORMS MAY DEVELOP IN CENTRAL MO ALONG A WEAK BOUNDARY SEPARATING DRIER BOUNDARY LAYER AIR IN SRN MO FROM A MOIST BOUNDARY LAYER IN NRN MO. ALTHOUGH WIND PROFILES ARE NOT PARTICULARLY IMPRESSIVE...MODERATE INSTABILITY MAY SUPPORT A FEW STORMS WITH MARGINALLY SEVERE HAIL/WIND. ...AZ... THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED ALONG THE RIM AND DESPITE ONLY 10-15 KT NLY MID LEVEL WINDS...STORMS MAY EVENTUALLY COLD POOL AND MOVE SSWWD TOWARD PRC AND WEST OF PHX LATE THIS EVENING. HOWEVER..STORM COMPLEX IS NOT AS IMPRESSIVE AS THIS SAME TIME LAST NIGHT AND SURFACE TEMPERATURES ARE ALSO ABOUT 5 DEGREES COOLER. ISOLATED WIND/HAIL THREAT MAY PERSIST THROUGH THE EVENING HOURS... BUT THINK SYSTEM WILL BE LESS ROBUST THAN LAST NIGHT. ...CENTRAL HIGH PLAINS... THUNDERSTORMS MOVING THROUGH WRN NEB/NERN CO WERE ASSOCIATED WITH A WEAK SHORTWAVE TROUGH MOVING THROUGH THE AREA. STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR MAY RESULT IN MARGINALLY SEVERE HAIL/WIND THE NEXT HOUR OR SO. HOWEVER...THE STORMS SHOULD WEAKEN QUICKLY THEREAFTER AS THE BOUNDARY LAYER COOLS/STABILIZES. ...ERN/LA... SEVERE THREAT WAS INHIBITED TODAY DUE TO EXTENSIVE CLOUDS/ PRECIPITATION AND RESULTANT WEAK INSTABILITY. MODELS MAINTAIN A FORECAST OF A 30-40 KT SLY LLJ OVERNIGHT AS UPPER LOW IN SERN TX LIFTS SLOWLY NWD. HOWEVER...THE DEEP UNIDIRECTIONAL SLY WINDS SUGGEST THE TORNADO THREAT IS LOW. ...OH... BAND OF STORMS ASSOCIATED WITH UPPER TROUGH WERE MOVING INTO CENTRAL OH THIS EVENING. A FEW HAIL/WIND EVENTS ARE POSSIBLE FOR THE NEXT 1 TO 2 HOURS...BUT STORMS SHOULD WEAKEN SHORTLY AS THE STORMS MOVE INTO A MORE STABLE ENVIRONMENT. ..IMY.. 07/27/2006  From swody1 at goshenarc.org Thu Jul 27 01:21:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 26 Jul 2006 21:21:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270115 SWODY1 SPC AC 270113 DAY 1 CONVECTIVE OUTLOOK CORR 1 NWS STORM PREDICTION CENTER NORMAN OK 0813 PM CDT WED JUL 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MS EWD INTO THE LOWER OH VALLEY... CORRECTED FOR TITLE IN 5TH PARAGRAPH ...MID MS AND LOWER OHIO VALLEYS... ALTHOUGH SHORTWAVE TROUGH HAS MOVED EAST OF THE AREA...CONVERGENCE AND HEATING WAS ENOUGH TO INITIATE SCATTERED THUNDERSTORMS ALONG SURFACE TROUGH THAT EXTENDED FROM SRN LOWER MI SWWD TO NEAR THE MO/IA BORDER. STRONGEST STORMS WERE LOCATED ACROSS CENTRAL IL WHERE MODERATE TO STRONG INSTABILITY WAS PRESENT WITH MARGINALLY FAVORABLE DEEP LAYER SHEAR FOR SUPERCELLS...REFERENCE WW 646. THESE STORMS SHOULD SPREAD ENEWD INTO IND THIS EVENING...THOUGH THE INSTABILITY IS WEAKER EAST OF IL AND THE SEVERE THREAT SHOULD GRADUALLY DIMINISH OVERNIGHT. AS LOW LEVEL JET STRENGTHENS FROM SERN OK INTO CENTRAL MO THIS EVENING...STORMS MAY DEVELOP IN CENTRAL MO ALONG A WEAK BOUNDARY SEPARATING DRIER BOUNDARY LAYER AIR IN SRN MO FROM A MOIST BOUNDARY LAYER IN NRN MO. ALTHOUGH WIND PROFILES ARE NOT PARTICULARLY IMPRESSIVE...MODERATE INSTABILITY MAY SUPPORT A FEW STORMS WITH MARGINALLY SEVERE HAIL/WIND. ...AZ... THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED ALONG THE RIM AND DESPITE ONLY 10-15 KT NLY MID LEVEL WINDS...STORMS MAY EVENTUALLY COLD POOL AND MOVE SSWWD TOWARD PRC AND WEST OF PHX LATE THIS EVENING. HOWEVER..STORM COMPLEX IS NOT AS IMPRESSIVE AS THIS SAME TIME LAST NIGHT AND SURFACE TEMPERATURES ARE ALSO ABOUT 5 DEGREES COOLER. ISOLATED WIND/HAIL THREAT MAY PERSIST THROUGH THE EVENING HOURS... BUT THINK SYSTEM WILL BE LESS ROBUST THAN LAST NIGHT. ...CENTRAL HIGH PLAINS... THUNDERSTORMS MOVING THROUGH WRN NEB/NERN CO WERE ASSOCIATED WITH A WEAK SHORTWAVE TROUGH MOVING THROUGH THE AREA. STEEP LOW LEVEL LAPSE RATES...MODERATE INSTABILITY AND 25-35 KT EFFECTIVE SHEAR MAY RESULT IN MARGINALLY SEVERE HAIL/WIND THE NEXT HOUR OR SO. HOWEVER...THE STORMS SHOULD WEAKEN QUICKLY THEREAFTER AS THE BOUNDARY LAYER COOLS/STABILIZES. ...ERN TX/LA... SEVERE THREAT WAS INHIBITED TODAY DUE TO EXTENSIVE CLOUDS/ PRECIPITATION AND RESULTANT WEAK INSTABILITY. MODELS MAINTAIN A FORECAST OF A 30-40 KT SLY LLJ OVERNIGHT AS UPPER LOW IN SERN TX LIFTS SLOWLY NWD. HOWEVER...THE DEEP UNIDIRECTIONAL SLY WINDS SUGGEST THE TORNADO THREAT IS LOW. ...OH... BAND OF STORMS ASSOCIATED WITH UPPER TROUGH WERE MOVING INTO CENTRAL OH THIS EVENING. A FEW HAIL/WIND EVENTS ARE POSSIBLE FOR THE NEXT 1 TO 2 HOURS...BUT STORMS SHOULD WEAKEN SHORTLY AS THE STORMS MOVE INTO A MORE STABLE ENVIRONMENT. ..IMY.. 07/27/2006  From swody1 at goshenarc.org Thu Jul 27 05:26:47 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 27 Jul 2006 01:26:47 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270522 SWODY1 SPC AC 270520 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1220 AM CDT THU JUL 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MID MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER NORTHERN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS IN AZ... ...SYNOPSIS... A SERIES OF WEAK UPPER IMPULSES WILL MOVE THROUGH A BROAD UPPER TROUGH EXTENDING FROM THE NRN ROCKIES SEWD INTO THE OH VALLEY AND THEN NEWD INTO NEW ENGLAND. A WEAK TROPICAL SYSTEM OVER ERN TX IS EXPECTED TO LIFT NNEWD DURING THE PERIOD AND EVENTUALLY BECOME ABSORBED INTO THE UPPER TROUGH ACROSS THE MID MS VALLEY. ...MID MS VALLEY REGION... DEVELOPMENT OF SEVERE CONVECTION ONCE AGAIN WILL BE PROBLEMATIC AS TIMING OF SHORTWAVE TROUGHS AND MARGINAL SHEAR EXISTS FOR SEVERE STORMS. CURRENTLY THINKING IS SHORTWAVE TROUGH...LOCATED IN THE WRN DAKOTAS...WILL MOVE THROUGH ERN IA AT PEAK HEATING. THE LIFT FROM THIS SYSTEM PLUS THE FORECAST OF A REMNANT FRONT/BOUNDARY STRETCHING FROM NRN MO EWD INTO NRN IND IS EXPECTED TO PROVIDE THE FOCUS FOR STRONG/SEVERE CONVECTIVE DEVELOPMENT. A VERY MOIST BOUNDARY LAYER AND TEMPERATURES WARMING TO AT LEAST 90F WILL RESULT IN A UNSTABLE AIR MASS OVER MUCH OF THIS REGION. THE AMOUNT OF INSTABILITY AND 25 KT EFFECTIVE SHEAR SHOULD BE SUFFICIENT FOR SEVERE MULTICELL CLUSTERS. THE STORMS WOULD LIKELY WEAKEN TO MOSTLY BELOW SEVERE CRITERIA BY MID EVENING SINCE THE STORMS WILL BE PRIMARILY THERMODYNAMICALLY DRIVEN. ...NRN NEW ENGLAND... PRONOUNCED SHORTWAVE TROUGH...CURRENTLY MOVING THROUGH THE ERN GREAT LAKES REGION...WILL MOVE ACROSS NRN NEW ENGLAND DURING THE HEAT OF THE DAY. MID LEVEL WINDS ARE FORECAST TO INCREASE TO NEAR 30 KT WITH UNIDIRECTIONAL SWLY WINDS ABOVE THE BOUNDARY LAYER. THIS SHOULD PROVIDE A FAVORABLE ENVIRONMENT FOR BANDS/LINES OF STORMS TO DEVELOP. ALTHOUGH THE INSTABILITY WILL NOT BE PARTICULARLY STRONG...MID LEVEL LAPSE RATES WILL BE STEEPER THAN NORMAL...AROUND 7.5 C/KM. THE SHEAR IN COMBINATION WITH THE LARGE SCALE FORCING AND STEEP LAPSE RATES SHOULD FAVOR A FEW SEVERE WIND AND HAIL EVENTS DURING THE AFTERNOON/EARLY EVENING HOURS. ..AZ... RICH LOW LEVEL MOISTURE WILL AGAIN BE IN PLACE OVER MUCH OF THE AREA THURSDAY...SUPPORTING MODERATE TO STRONG INSTABILITY. THE MID LEVEL NLY WINDS ARE FORECAST TO STRENGTHEN AS THE UPPER HIGH SHIFTS NWD THROUGH NV. A SHORTWAVE TROUGH IN ERN UT IS ALSO EXPECTED TO ROTATE AROUND THE HIGH AND INTO NERN AZ DURING THE AFTERNOON. THE STRONGER MID/HIGH LEVEL WINDS WILL HELP TO MOVE CONVECTION/CLOUDS SWD OUT OF THE STATE THIS MORNING. ALTHOUGH THE HEATING LIKELY WILL NOT BE AS STRONG AS THE PAST SEVERAL DAYS... ONCE THE STORMS DEVELOP OVER THE HIGHER TERRAIN...THE STRONGER WINDS/SHEAR SHOULD CARRY THEM SWD INTO THE DESERT FLOORS WITH A THREAT FOR SEVERE WINDS AND PERHAPS SOME HAIL. ...NRN OH/WRN NY... WRF MODEL SUGGESTS THAT THE LAKE BREEZE WILL BECOME CONVECTIVELY ACTIVE DURING THE AFTERNOON. THE DEEP LAYER SHEAR WILL BE MARGINAL FOR SEVERE...BUT UNDIRECTIONAL WLY WINDS AND MLCAPE VALUES FROM 1500-2000 J/KG WOULD SUPPORT STRONG WIND GUSTS. ...KS... MID/HIGH LEVEL MOISTURE FROM THE MONSOONAL FLOW WILL SPREAD NEWD ACROSS KS AND HELP IN THE INITIATION OF LATE AFTERNOON THUNDERSTORMS. HOT TEMPERATURES AND STEEP LOW LEVEL LAPSE RATES MAY SUPPORT SOME STRONG/SEVERE WIND GUSTS. ..IMY/TAYLOR.. 07/27/2006  From swody1 at goshenarc.org Fri Jul 28 06:14:10 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 02:14:10 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 280614 SWODY1 SPC AC 280612 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0112 AM CDT FRI JUL 28 2006 VALID 281200Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS MID ATLANTIC...NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS WRN/NRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS UPPER MS VALLEY TO WRN LM... ...SYNOPSIS... PROGRESSIVE NRN STREAM FLOW WILL CONTINUE THROUGH PERIOD...FEATURING PRONOUNCED SHORTWAVE TROUGH NOW EVIDENT IN MOISTURE CHANNEL IMAGERY FROM LM SWWD ACROSS MO. THIS FEATURE IS FCST TO MOVE EWD ACROSS ERN GREAT LAKES...MID ATLANTIC AND NEW ENGLAND STATES THROUGH 29/00Z. MEANWHILE TROUGH NOW OVER NERN MB AND FAR NRN ONT SHOULD CONTINUE MOVING EWD OVER JAMES BAY REGION...WHILE ASSOCIATED LOW LEVEL COLD FRONT MOVES INTO NRN PLAINS. BY 29/06Z THIS FRONT SHOULD STALL INVOF ND/SD BORDER AS LEE CYCLONE INTENSIFIES OVER WRN SD. ANOTHER DIFFUSE FRONTAL ZONE WILL REMAIN QUASISTATIONARY FROM ERN NM ENEWD ACROSS OK AND OZARKS REGION...MODULATED ON MESOSCALE LEVEL BY NUMEROUS OUTFLOW BOUNDARIES. MEANWHILE...MID-UPPER LEVEL LOW -- WELL DEFINED IN MOISTURE CHANNEL IMAGERY ATTM OVER NWRN NM -- IS FCST TO DRIFT SWWD OVER ERN AZ....ENHANCING NELY GRADIENT FLOW AROUND RIM OF NV ANTICYCLONE. ...MID ATLANTIC...NEW ENGLAND... SCATTERED TSTMS ARE FCST TO DEVELOP IN FAVORABLY MOIST AIR MASS FROM LATE MORNING THROUGH AFTERNOON...ORGANIZING INTO ONE OR MORE BANDS/CLUSTERS WHILE MOVING EWD ACROSS REGION. MAIN THREAT WILL BE DAMAGING WINDS. HOWEVER...SUFFICIENT VEERING IS EVIDENT IN FCST HODOGRAPHS FROM ERN PA ACROSS SRN/CENTRAL NEW ENGLAND TO SUPPORT SUPERCELL MODE WITH ANY RELATIVELY DISCRETE CONVECTION. MAIN UNCERTAINTY ATTM IS STRENGTH OF DIABATIC HEATING IN ADVANCE OF CLOUD/PRECIP SHIELD ASSOCIATED WITH ONGOING MCS. THIS RENDERS PROGRESSIVELY MORE UNCERTAINTY WITH WWD EXTENT NOW EVIDENT FROM LE SWWD ACROSS NWRN OH AND INDIANA. VERTICAL WIND PROFILES AND LOW LEVEL SHEAR EACH ARE EXPECTED TO WEAKEN WITH SWWD EXTENT ACROSS APPALACHIANS AND OH VALLEY REGION...FAVORING MORE SPORADIC...PULSE/MULTICELL SEVERE THREAT AND LOWER PROBABILITIES. ...AZ... CLOUD COVER NOW EVIDENT OVER PORTIONS NRN/WRN AZ -- RESIDUE FROM EARLIER CONVECTION -- SHOULD ABATE ENOUGH BY UPCOMING AFTERNOON TO PERMIT STRONG INSOLATION ACROSS LARGE PORTION OF REGION...W OF APCHG MID/UPPER LEVEL PERTURBATION. SFC DEW POINTS REMAINING UPPER 60S TO LOW 70S F IN DESERTS AND NEAR 60 IN HIGHER ELEVATIONS WILL FURTHER CONTRIBUTE TO WEAK MID-LATE AFTERNOON CINH AND TSTM POTENTIAL. ATOP THAT INCREASINGLY UNSTABLE BOUNDARY LAYER...AFOREMENTIONED CORRIDOR OF ENHANCED MIDLEVEL NELYS WILL ENHANCE DEEP-LAYER SHEAR FAVORING SOME ORGANIZED SVR THREAT. POTENTIAL EXISTS FOR TSTMS TO FORM OVER HIGHER ELEVATIONS AND ORGANIZE INTO OUTFLOW DOMINANT MCS MOVING INTO WELL MIXED/STRONGLY HEATED BOUNDARY LAYERS OVER DESERTS. MAIN THREAT IS DAMAGING WIND...THOUGH ISOLATED HAIL MAY BE A CONCERN WHEN STORMS ARE STILL FAIRLY DISCRETE. FARTHER SE ACROSS SERN AND EXTREME E-CENTRAL AZ...AND SWRN NM...MORE UNCERTAINTIES EXIST REGARDING STRENGTH OF AFTERNOON DESTABILIZATION...IN WAKE OF MCS DURING DAY THURSDAY AND ANOTHER COMPLEX NOW MOVING SWWD ACROSS THAT AREA. FLOW ALOFT ALSO IS EXPECTED TO BE WEAKER AND LOSE ELY COMPONENT WITH SEWD GEOGRAPHIC EXTENT....INHIBITING BOTH VERTICAL SHEAR AND PROPAGATION POTENTIAL ONTO DESERTS FROM ERN PORTIONS MOGOLLON RIM. THEREFORE SVR PROBABILITIES ARE KEPT MRGL ATTM. ...UPPER MIDWEST... SCATTERED TSTMS SHOULD DEVELOP DURING AFTERNOON INTO EARLY EVENING HOURS...PERHAPS ORGANIZING INTO MCS WITH DAMAGING GUSTS AND LARGE HAIL POSSIBLE. NEARLY UNIDIRECTIONAL DEEP-LAYER WIND PROFILES ARE FCST...ALONG WITH MLCAPES SOMETIMES EXCEEDING 2500 J/KG. THIS SUPPORTS POTENTIAL FOR STRONG-SEVERE DOWNDRAFTS...GIVEN STRONG SFC HEATING AND FAVORABLE BOUNDARY LAYER MOISTURE EXPECTED. AFTER DARK...STRONG LOW LEVEL WAA AND AT LEAST MRGL MOISTURE WILL SUPPORT POTENTIAL FOR ELEVATED MCS FORMATION ACROSS PORTIONS ND/MN. STEEP LAPSE RATES AND FAVORABLE EFFECTIVE SHEARS WILL SUPPORT POTENTIAL FOR TSTMS TO PRODUCE ISOLATED LARGE HAIL. ...OZARKS TO NW TX... WIDELY SCATTERED TSTMS ARE EXPECTED TO DEVELOP AGAIN THIS AFTERNOON INVOF WEAK LOW LEVEL BAROCLINIC ZONE...ESPECIALLY ALONG OUTFLOW BOUNDARIES AND THEIR INTERSECTIONS. HOT...DEEPLY MIXED SUBCLOUD LAYERS WILL PROVIDE THREAT FOR A FEW DAMAGING WIND EVENTS WITH STRONGEST PULSE/MULTICELLULAR ACTIVITY. HOWEVER...ORGANIZED SVR IS NOT ANTICIPATED BECAUSE OF WEAK WINDS/SHEAR AND OUTFLOW-DOMINANT/SHORT-LIVED NATURE OF ANY GIVEN MULTICELL EVENT. SVR POTENTIAL WILL DIMINISH MARKEDLY AFTER SUNSET WHEN DIABATIC COOLING REMOVES SBCAPE. ..EDWARDS/TAYLOR.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 12:38:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 08:38:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281239 SWODY1 SPC AC 281237 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0737 AM CDT FRI JUL 28 2006 VALID 281300Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EARLY TONIGHT FROM SERN NY AND ERN PA INTO SRN NEW ENGLAND.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF NRN WI INTO SRN UPR MI.... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF WRN AZ.... ...SYNOPSIS... WATER VAPOR IMAGERY SHOWS VERY WELL THE MID/UPPER LEVEL TROUGH MOVING EWD ACROSS ERN LOWER MI INTO THE MID MS VALLEY. THIS TROUGH IS EXPECTED TO CONTINUE MOVG EWD ACROSS THE LOWER GREAT LAKES TODAY AND NEW ENGLAND TONIGHT. MID LEVEL RIDGING IS ALSO INDICATED ACROSS THE NRN PLAINS. THIS WILL RESULT IN WNWLY FLOW ALOFT OVER THE UPPER GREAT LAKES THAT WILL BRING A WEAK FRONT SEWD INTO NRN WI THIS AFTERNOON. MEANWHILE...SUMMERTIME MID/UPPER LEVEL RIDGE WILL BE OVER THE CENTRAL INTERMOUNTAIN REGION TODAY...BUT ADVANCE INTO THE CENTRAL PLAINS TONIGHT AS WEAK INVERTED TROUGH MOVES WWD ACROSS NM/AZ. ...PARTS OF NY AND SRN NEW ENGLAND... EARLY VISIBLE SATELLITE IMAGES INDICATE PLENTY OF CLOUD COVER EAST OF MID/UPPER LEVEL TROUGH ACROSS NY STATE INTO PA AND WEST INTO OHIO. THIS WILL LIMIT AMOUNT OF INSTABILITY ACROSS NY INTO NEW ENGLAND...AND 06Z RUN OF THE NAM SUPPORTED THIS NOTION. 00Z RUN OF THE WRF INDICATED STRONG THUNDERSTORMS ACROSS THIS REGION THIS AFTERNOON...BUT WAS ALSO MORE UNSTABLE THAN THE NAM. POOR LAPSE RATES WERE EVIDENT IN BOTH NAM AND RUC MODELS WITH LOW/MID LEVEL LAPSE RATES JUST UNDER 6C/KM. WSWLY LOW LEVEL FLOW OF 30-35 KT COUPLED WITH WSWLY 50 KT MID LEVEL FLOW PROVIDES SOME SPEED SHEAR FOR STRONG THUNDERSTORMS AHEAD OF THE ADVANCING TROUGH...BUT LITTLE IN THE WAY OF DIRECTIONAL SHEAR. FORECAST SOUNDINGS DO SHOW SOME STEEPER LAPSE RATES IN THE LOWEST 3KM ABOVE THE SFC INDICATING THAT STORMS MOVING INTO SERN NY AND SRN NEW ENGLAND WILL HAVE THE POTENTIAL FOR STRONG WIND GUSTS LATER THIS MORNING AND THIS AFTERNOON. BUT...GIVEN THE OVERALL LIMITED POTENTIAL WITH MOIST LAPSE RATES AND LIMITED INSTABILITY...HAVE LOWERED PROBABILITIES DOWNWARD...AND DIMINISHED SIZE OF SLGT RISK AREA TO SERN NY STATE AND ERN PA EWD S OF THE NRN MA BORDER. ...PARTS OF NRN AND WRN WI INTO THE U.P. OF MI... 00Z WRF MODELS SHOWS STRONG SIGNALS OF POTENTIAL LINE OF STRONG/SEVERE THUNDERSTORMS MOVING SEWD ACROSS NWRN...N CENTRAL AND NERN WI THIS AFTERNOON. FRONTAL BOUNDARY ACROSS NWRN MN THIS MORNING WILL TRACK SEWD AS WNWLY FLOW DEVELOPS DUE TO MINOR RIDGING FARTHER W OVER THE NRN HIGH PLAINS. THIS BOUNDARY WILL MOVE INTO AREAS WHERE IT IS POTENTIALLY UNSTABLE WITH CAPES BETWEEN 1000 AND 1500 J/KG AND MID LEVEL LAPSE RATES ARE AROUND 7C/KM. THUS...SOME SEVERE THUNDERSTORMS ARE POSSIBLE LATER TODAY AND EARLY TONIGHT ACROSS NRN WI INTO S CENTRAL UPR MI WITH MAIN THREAT BEING DAMAGING WINDS. MODELS INDICATE THE POTENTIAL FOR SOME THUNDERSTORMS LATER TONIGHT ACROSS IN WEAK WARM ADVECTION REGIME OVER N CENTRAL MN AS SWLY LOW LEVEL JET DEVELOPS OVER CENTRAL SD INTO W CENTRAL MN. ISOLATED STRONG THUNDERSTORMS ARE POSSIBLE IN ASSOCIATION WITH WEAK MCS DEVELOPING IN EXIT REGION OF LOW LEVEL JET. ...PARTS OF AZ... WEAK MID/UPPER LEVEL INVERTED TROUGH IS FORECAST TO MOVE WWD FROM WRN NM THIS MORNING INTO CENTRAL AND WRN SECTIONS OF AZ LATE TONIGHT. LATEST SURFACE ANALYSIS SHOWS BAND OF MID 60S TO LOW 70 DEW POINTS ACROSS S CENTRAL AND WRN AZ THIS MORNING. THE MODELS DESTABILIZE THE AIR MASS THIS AFTERNOON WHEN MIXED LAYER CAPE REACHES BETWEEN 1000 AND 1500 J/KG. WITH LOW LEVEL LAPSE RATES AROUND 7C/KM AND DCAPE JUST OVER 1100 J/KG...LOOK LIKE THUNDERSTORM ACTIVITY WILL CARRY THE POTENTIAL FOR DOWNBURST WINDS THIS AFTERNOON AND EARLY TONIGHT. ...PARTS OF OK... SEVERAL WEAK BOUNDARIES REMAIN OVER WRN AND NRN OK INTO SWRN MO IN RESPONSE TO HIGH-BASED THUNDERSTORM ACTIVITY ON THURSDAY. DAYTIME HEATING SHOULD ONCE AGAIN FAVOR AIR MASS TYPE THUNDERSTORMS LATE THIS AFTERNOON AND EARLY EVENING ACROSS NRN OK INTO SWRN MO AS AIR MASS WILL BECOME VERY UNSTABLE WITH MLCAPES JUST BELOW 2700 J/KG AND MID LEVEL LAPSE RATES NEAR 7C/KM. THUS...MUCH OF THE ACTIVITY SHOULD REMAIN BELOW SEVERE LEVELS WITH STRONG GUSTY WINDS ARE POSSIBLE ACROSS AREA. ..MCCARTHY.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 16:30:06 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 12:30:06 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 281630 SWODY1 SPC AC 281628 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1128 AM CDT FRI JUL 28 2006 VALID 281630Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE MID ATLANTIC INTO THE SRN NEW ENGLAND... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A PART OF THE NRN PLAINS INTO THE NRN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ... ...MID ATLANTIC INTO SRN NEW ENGLAND... ACTIVE DAY FOR THUNDERSTORMS EXPECTED ACROSS THIS REGION AS SLOW MOVING MID LEVEL TROUGH AND ACCOMPANYING 40+ KT MID LEVEL JET /30+ KT WSWLY LLJ/ OVERSPREAD THE NORTHEAST. AIR MASS REMAINS QUITE MOIST WITH SURFACE DEW POINTS WELL INTO THE 70S AHEAD OF THIS FEATURE...WHICH WILL SUPPORT A VERY WARM/HUMID WARM SECTOR AS AFTERNOON HIGHS REACH INTO AT LEAST THE UPPER 80S/LOWER 90S. DESPITE LARGE LOW LEVEL THETA-E VALUES IN PLACE...WEAK LAPSE RATES / H7 TO H5 LAPSE RATES AOB 6 C KM-1 / WILL LIMIT AVAILABLE CAPE. REGARDLESS...MLCAPE SHOULD EXCEED 2000 J/KG ACROSS THE MID ATLANTIC AND 1500 J/KG INTO SRN NEW ENGLAND BY THE MID AFTERNOON. DEEP LAYER SHEAR FROM 30-40 KT WILL BE SUPPORTIVE OF ORGANIZATION INTO LINES/CLUSTERS. PRIMARY NEGATIVES FOR SUSTAINED OR MORE WIDESPREAD SEVERE WILL BE THE LIMITED LAPSE RATES AND RATHER WEAK LOW LEVEL CONVERGENCE ACROSS THE REGION. HOWEVER...POTENTIAL FOR STORM-SCALE ORGANIZATION AND AMOUNT INSTABILITY...ALONG WITH STEEPENING LOW LEVEL LAPSE RATES...SHOULD SUPPORT DAMAGING WINDS THIS AFTERNOON/EVENING. IN ADDITION...PW/S AROUND 2 INCHES AND RICH LOW LEVEL MOISTURE SOURCE WILL ENHANCE HEAVY RAINFALL POTENTIAL AS THUNDERSTORMS INCREASE THROUGH THE AFTERNOON AND SPREAD EWD OFF THE COAST BY THE EARLY TO MID EVENING /REFERENCE LATEST QPF GUIDANCE FROM HPC/. ...NRN PLAINS INTO THE NRN MS RIVER VALLEY AND NRN GREAT LAKES... MODELS STILL IN AGREEMENT IN INCREASING THUNDERSTORMS NEAR SURFACE COLD FRONT NOW EXTENDING ACROSS NRN MN AS IT SAGS SSEWD INTO NRN WI WRN U.P. OF MI THIS AFTERNOON. WARM SECTOR WILL REMAIN VERY MOIST WITH 70+F SURFACE DEW POINTS ALREADY IN PLACE OVER NRN MI/NRN WI. MODIFIED 12Z SOUNDINGS AT MPX AND GRB AND RUC FORECAST SOUNDINGS ACCOUNTING FOR MID/UPPER 90F SURFACE TEMPERATURES AND DEW POINTS AROUND 70F INDICATE MLCAPE WILL EXCEED 2500 J/KG OVER MUCH OF THIS REGION WITH LITTLE OR NO MLCIN BY 21Z. IN ADDITION...THE 12Z SOUNDING AT INL INDICATES 40 KT OF FLOW AROUND 3 KM WHICH IS FORECAST TO OVERSPREAD THE NRN GREAT LAKES THROUGH THE DAY. AS CAP WEAKENS...SURFACE FRONT SHOULD SUPPORT INCREASED THUNDERSTORM DEVELOPMENT FROM PORTIONS OF NRN/CENTRAL MN ACROSS NRN WI INTO THE WRN U.P. OF MI. DEEP LAYER SHEAR FROM 25-35 KT IS FORECAST TO BE MARGINAL FOR SUPERCELLS...BUT MORE THAN ADEQUATE FOR LINES/CLUSTERS GIVEN EXTREME INSTABILITY. DAMAGING WINDS WILL LIKELY BE PRIMARY SEVERE THREAT AS STORMS SHIFT SEWD THROUGH THE EVENING...THOUGH AN ISOLATED TORNADO THREAT MAY ALSO ACCOMPANY ANY SUSTAINED SUPERCELL STRUCTURE ESPECIALLY AS WLY LLJ INCREASES EARLY THIS EVENING. SEVERE THREAT SHOULD THEN SHIFT NWWD INTO ND ALONG NOSE OF A SLY LLJ...WHICH THE VEERS TO MORE SWLY LATER TONIGHT AHEAD OF SHORTWAVE TROUGH NOW SKIRTING NWRN MT. THIS SYSTEM WILL LIKELY RIDE EWD ACROSS ND ATOP LARGER UPPER RIDGE AND TURN SEWD INTO NRN MN BY THE END OF THE PERIOD. ELEVATED STORMS WILL LIKELY DEVELOP AFTER DARK INTO ND ALONG NOSE OF INCREASING LLJ ALONG AND NORTH OF SURFACE COLD FRONT EXPECTED TO STALL E-W NEAR THE SD-ND BORDER. VERY STEEP MID LEVEL LAPSE RATES...FEED OF ABUNDANT LOW LEVEL MOISTURE AND STRONG CLOUD-LAYER SHEAR SUGGEST ACTIVITY WILL BECOME INCREASINGLY ORGANIZED/INTENSE AFTER 03Z AND BUILD UPSCALE AS AN MCS ACROSS ERN ND INTO NWRN MN LATER TONIGHT. WARM MID LEVEL AIR MASS MAY ACT TO HINDER HAIL GROWTH...THOUGH LARGE HAIL WILL LIKELY ACCOMPANY STRONGER CORES GIVEN EFFECTIVE SHEAR AROUND 50 KT AND LIKELIHOOD OF ELEVATED SUPERCELLS. OVERALL SETUP WILL BECOME INCREASINGLY FAVORABLE FOR SEVERE MCS DEVELOPMENT...POSSIBLY IN THE FORM OF A BOW ECHO SYSTEM...ESPECIALLY IF STORMS CAN ROOT INTO SHALLOWER STABLE LAYER NEAR THE SURFACE FRONT LATER TONIGHT WHICH WILL CONTINUE INTO THE DAY 2 FORECAST PERIOD. ...AZ... WELL DEFINED MID/UPPER LEVEL INVERTED TROUGH AND ASSOCIATED LOW CENTER WILL CONTINUE A SLOW MOTION WSWWD INTO WRN AZ TODAY AND INTO CENTRAL AZ LATER TONIGHT. AIR MASS REMAINS QUITE MOIST WITH LATEST SURFACE ANALYSIS INDICATING MID 60S TO LOW 70 DEW POINTS IN PLACE ACROSS S CENTRAL AND WRN AZ THIS MORNING. IN ADDITION...MID LEVEL CLOUDS HAVE ALL BUT CLEARED MUCH OF CENTRAL AZ THIS MORNING WHICH WILL ALLOW A MODERATE TO STRONGLY UNSTABLE AIR MASS TO DEVELOP AHEAD OF THIS SYSTEM. RUC FORECAST SOUNDINGS INDICATE MLCAPE WILL LIKELY EXCEED 2500-3000 J/KG OVER LOWER ELEVATIONS GIVEN LOWER 70F SURFACE DEW POINTS AND AFTERNOON HIGHS WELL INTO THE 90S. AS LARGE SCALE ASCENT INCREASES...STORMS WILL LIKELY BECOME WIDESPREAD OVER MUCH OF AZ TODAY AND CONTINUE WELL INTO THE NIGHT. APPEARS DAMAGING WINDS AND VERY HEAVY RAINFALL...ALONG WITH SOME HAIL...WILL ACCOMPANY THIS ACTIVITY. ..EVANS/GUYER.. 07/28/2006  From swody1 at goshenarc.org Fri Jul 28 20:16:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 16:16:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 282014 SWODY1 SPC AC 282012 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0312 PM CDT FRI JUL 28 2006 VALID 282000Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SRN NEW ENGLAND TO THE MID ATLANTIC REGION... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A PART OF THE NRN PLAINS INTO THE NRN GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ... ...MID ATLANTIC INTO SRN NEW ENGLAND... STRONG FORCING FOR ASCENT AHEAD OF SHORT WAVE TROUGH...NOW LOCATED FROM SRN QUEBEC TO THE CENTRAL APPALACHIANS...WILL MAINTAIN LINE OF THUNDERSTORMS EXPECTED TO MOVE EWD ACROSS SRN NEW ENGLAND AND THE REMAINDER OF THE MID ATLANTIC REGION INTO EARLY-MID EVENING. MODERATE INSTABILITY EAST OF ONGOING LINE OF STORMS COMBINED WITH STRONG DEEP LAYER SHEAR WILL CONTINUE TO SUPPORT ORGANIZED SEVERE STORMS WITH DAMAGING WINDS BEING THE PRIMARY THREAT INTO THE EVENING. ...NRN PLAINS INTO THE NRN MS VALLEY AND NRN GREAT LAKES... EARLY AFTERNOON SURFACE ANALYSIS SHOWED A COLD FRONT EXTENDING FROM NERN MN SWWD TO ALONG THE ND/SD BORDER...WITH A PRE-FRONTAL TROUGH HAVING MOVED INTO THE WRN U.P. OF MI AND NWRN WI/PARTS OF EAST CENTRAL MN. COLD FRONT WILL CONTINUE TO MOVE SWD AND SHOULD OVERTAKE THE PRE-FRONTAL TROUGH BY THIS EVENING. STRONG SURFACE HEATING ALONG/S OF THESE BOUNDARIES WITHIN VERY MOIST AIR MASS HAS ALLOWED AIR MASS TO BECOME VERY UNSTABLE ACROSS THE SRN THREE QUARTERS OF MN WITH AN AXIS OF MODERATE INSTABILITY EXTENDING EWD ALONG THE PRE-FRONTAL TROUGH. THE COMBINATION OF THE SURFACE HEATING AND ASCENT WITHIN THE RIGHT ENTRANCE REGION OF A 50 KT NWLY MID LEVEL JET...NOW LOCATED OVER NRN MN...ARE EXPECTED TO AID IN FURTHER WEAKENING OF INHIBITION. THUS...THUNDERSTORMS SHOULD CONTINUE TO DEVELOP WWD ALONG THE PRE-FRONTAL TROUGH...AND ALSO ALONG THE COLD FRONT AS THIS BOUNDARY MOVES SWD INTO CENTRAL MN/NRN WI AND THE U.P. OF MI. OBJECTIVE ANALYSES INDICATED EFFECTIVE BULK SHEAR VALUES HAVE INCREASED SUPPORTING ORGANIZED SEVERE STORMS WITH A FEW SUPERCELLS POSSIBLE. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREATS. HOWEVER...GIVEN MOIST BOUNDARY LAYER COMBINED WITH AN INCREASING SWLY LLJ EXTENDING INTO EAST CENTRAL MN/NRN WI BY EARLY EVENING...LOW LEVEL SHEAR IS EXPECTED TO INCREASE POTENTIALLY SUPPORTING AN ISOLATED TORNADO OR TWO. THIS LLJ WILL VEER TO WLY OVERNIGHT AND SHOULD MAINTAIN A CLUSTER OF STORMS SPREADING EWD TOWARD NRN LOWER MI/ERN U.P. OF MI. WEAKER INSTABILITY AHEAD OF THIS OVERNIGHT ACTIVITY SHOULD LIMIT THE ERN EXTENT OF SEVERE STORMS. BY LATE EVENING...SEVERE THREAT IS EXPECTED TO SHIFT WNWWD INTO ND/ NRN SD AS WAA INCREASES NORTH OF SURFACE FRONT AND ALONG NOSE OF STRENGTHENING NRN PLAINS SLY LLJ. THIS LLJ IS EXPECTED TO STRENGTHEN IN RESPONSE TO A SHORT WAVE TROUGH...NOW LOCATED OVER NERN MT/SRN SASKATCHEWAN...RIDING THE TOP OF THE RIDGE ACROSS SRN CANADA/ND TOWARD NRN MN. SUFFICIENT INFLOW OF MODERATE ELEVATED INSTABILITY AND 50-60 KT OF EFFECTIVE BULK SHEAR SUGGEST LIKELIHOOD FOR MCS DEVELOPMENT WITH EMBEDDED ELEVATED SUPERCELLS PRODUCING LARGE HAIL. THE LLJ SHOULD VEER TO SWLY ALLOWING THE MCS TO MOVE ESEWD INTO PARTS OF NRN/CENTRAL MN BY 12Z SATURDAY. DAMAGING WINDS MAY BECOME A THREAT IF STORMS CAN ROOT INTO SHALLOWER STABLE LAYER NEAR THE SURFACE LATER TONIGHT WHICH WILL CONTINUE INTO THE DAY 2 FORECAST PERIOD. ...AZ... WELL DEFINED MID/UPPER LEVEL CIRCULATION...CURRENTLY CENTERED ALONG AZ/NM BORDER...WILL CONTINUE TO PROGRESS SLOWLY SWWD THIS FORECAST PERIOD. ASCENT AHEAD OF THIS FEATURE AND SURFACE HEATING WILL SUPPORT ADDITIONAL THUNDERSTORM DEVELOPMENT ACROSS THE HIGHER TERRAIN OF CENTRAL/NWRN AZ INTO SWRN UT/SRN NV. NLY STEERING FLOW SUGGESTS STORMS ARE EXPECTED TO MOVE/PROPAGATE SWD TOWARD THE LOWER ELEVATIONS...WITH DAMAGING WINDS POSSIBLE. IN ADDITION... 25-30 KT OF DEEP LAYER SHEAR COMBINED WITH MODERATE INSTABILITY WILL SUPPORT A FEW SUPERCELLS PRODUCING LARGE HAIL AND STRONG WIND GUSTS. ..PETERS.. 07/28/2006  From swody1 at goshenarc.org Sat Jul 29 01:05:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 28 Jul 2006 21:05:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290105 SWODY1 SPC AC 290103 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0803 PM CDT FRI JUL 28 2006 VALID 290100Z - 291200Z ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS UPPER MIDWEST... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS SWRN CONUS... ...SYNOPSIS... UPPER AIR PATTERN IS CHARACTERIZED BY PROGRESSIVE NRN STREAM FLOW BELT...DOWNSTREAM FROM STRONG TROUGH LOCATED OFF BC COAST. SHORTWAVE TROUGH -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY OVER WRN NEW ENGLAND -- WILL MOVE OFFSHORE TONIGHT. RELATED SFC TROUGH AND COLLOCATED MCS ALREADY HAS WEAKENED AND MOVED LARGELY OFFSHORE...DROPPING SVR POTENTIAL OVER NERN CONUS. FARTHER W...WELL-DEFINED SFC COLD FRONT WILL CONTINUE MOVING SEWD FROM ONT AND LS ACROSS NERN MN...REMAINDER LS...AND UPPER MI THROUGH REMAINDER PERIOD. WRN PORTION OF THIS FRONT -- NOW ANALYZED INVOF ND/SD BORDER -- SHOULD REMAIN STATIONARY OR DRIFT SLIGHTLY NWD E OF COMBINED LEE/FRONTAL-WAVE CYCLONE THAT IS ANALYZED ACROSS NWRN SD. MEANWHILE...MID-UPPER LEVEL LOW REMAINS WELL DEFINED IN MOISTURE CHANNEL IMAGERY OVER AZ/NM BORDER...WITH WEAK WWD TO SWWD DRIFT ANTICIPATED THROUGH TONIGHT. ...AZ... SCATTERED-NUMEROUS TSTMS HAVE DEVELOPED FROM SWRN UT SSEWD ACROSS W-CENTRAL AZ...SOME OF WHICH HAVE PRODUCED LARGE HAIL. REF SPC WW 651 AND RELATED MESOSCALE DISCUSSION FOR NEAR-TERM DETAILS. WELL MIXED BOUNDARY LAYERS WILL SUPPORT POTENTIAL FOR EVOLUTION INTO FORWARD-PROPAGATING MCS. ASSOCIATED DAMAGING WIND POTENTIAL MAY INCREASE WSWWD ACROSS LOWER ELEVATIONS THROUGH REMAINDER EVENING AS ACTIVITY PROPAGATES THAT WAY...WITH HELP FROM MIDLEVEL NELYS APPARENT IN VWP FROM FLG/PHX. BROAD AREA OF FAVORABLE INSTABILITY -- WITH MLCAPES 1500-3000 J/KG -- REMAINS ACROSS SWATH FROM SWRN AZ NWWD ACROSS CO RIVER VALLEY REGION AHEAD OF THIS ACTIVITY...IN PROSPECTIVE INFLOW REGION. ...UPPER MIDWEST... REF SPC WW 650 AND ACCOMPANYING MESOSCALE DISCUSSIONS FOR NOWCAST DETAILS REGARDING SVR THREAT WITH ONGOING ACTIVITY OVER NRN WI AND UPPER MI. AS WRN GREAT LAKES AREA OF CONVECTION GRADUALLY WEAKENS...GREATEST SVR POTENTIAL IS FCST TO TRANSFER WWD TO ND AND PERHAPS EXTREME NRN SD NEXT FEW HOURS. SVR TSTMS MAY EVOLVE FROM ONGOING HIGH-BASED CONVECTION INVOF ND/SD BORDER...IN ENVIRONMENT OF FAVORABLE DEEP-LAYER SHEAR. INTENSELY HEATED/MIXED SUBCLOUD LAYERS WILL FAVOR MAINTENANCE OF STRONG-SVR DOWNDRAFTS TO SFC...AS WELL AS ANY LARGE HAIL THAT MAY BE GENERATED ALOFT. 00Z BIS RAOB SHOWS STRONG CAP N OF SFC FRONT BUT ALSO STRONG LOW LEVEL WAA. THIS PROCESS SHOULD CONTINUE THROUGH REMAINDER TONIGHT OVER MUCH OF CENTRAL/ERN ND...SHIFTING INTO W-CENTRAL/NWRN MN...WITH ENOUGH MOISTENING THROUGH AROUND 06Z TO SUPPORT PARCELS ISENTROPICALLY RAISED TO LFC. THIS PROCESS...COMBINED WITH POTENTIAL FOR DAMAGING WIND PRODUCING MCS EVOLVING FROM CURRENT SFC-BASED DEVELOPMENT FARTHER W...INDICATES RISK FOR SVR SHOULD BE MAINTAINED OVER THIS REGION FOR OVERNIGHT HOURS. ONE OR TWO MCS SHOULD EVOLVE OVERNIGHT...MOVING GENERALLY ESEWD ACROSS MN AND CARRYING SVR POTENTIAL OVER INTO DAY-2 PERIOD. ..EDWARDS.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 06:05:31 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 02:05:31 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 290605 SWODY1 SPC AC 290603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT SAT JUL 29 2006 VALID 291200Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN ND TO LOWER MI... ...SYNOPSIS... NRN STREAM PATTERN WILL BE CHARACTERIZED BY MEAN RIDGING OVER CENTRAL/NRN PLAINS...AND HEIGHT FALLS OVER PACIFIC NW LATE IN PERIOD AHEAD OF PROGRESSIVE TROUGH NOW OFFSHORE BC. MIDDLE/UPPER LEVEL LOW -- NOW EVIDENT IN MOISTURE CHANNEL IMAGERY INVOF AZ/NM BORDER -- IS EXPECTED TO WEAKEN GRADUALLY. PART OF ITS VORTICITY FIELD MAY SHIFT NEWD ACROSS SRN CO AGAIN...WITH THE REST WEAKENING OVER AZ. AT SFC...PRONOUNCED FRONTAL ZONE WILL EXTEND FROM COMBINED LEE-SIDE/FRONTAL-WAVE LOW OVER SD...EWD ACROSS MN THEN ESEWD OVER LOWER MI. FRONT WILL BE SHIFTED SWD ON MESOSCALE BY MCS OUTFLOWS. ...UPPER GREAT LAKES...UPPER MIDWEST... TWO PRINCIPAL SVR EPISODES ARE POSSIBLE ACROSS THIS REGION...INITIALLY WITH EWD EXTENSION OF MCS NOW OVER ND/NERN SD...AND SUBSEQUENTLY WITH AFTERNOON/EVENING DEVELOPMENT ALONG AND N OF FRONTAL/OUTFLOW BOUNDARY LEFT BEHIND BY FIRST COMPLEX. TO SOME EXTENT...LARGEST SVR PROBABILITIES REPRESENT SPATIAL OVERLAY OF BOTH. ONGOING STRONG-SVR TSTMS ACROSS PORTIONS WI...AS OF 05Z...CONTINUE TO MOVE SFC BAROCLINIC ZONE FRONT SWD ACROSS THAT REGION. THIS PROCESS WILL BE REINFORCED BY MCS NOW PRIMARILY OVER ND. MEANWHILE COMBINATION OF CLOUD DEBRIS...AREAS OF PRECIP AND LACK OF SUBSTANTIAL ISALLOBARIC FORCING WILL KEEP FRONTAL ZONE ALONG OR JUST S OF PRESENT POSITION ACROSS MI. THEREFORE FAVORABLE MCS CORRIDOR SHOULD BE FROM E-CENTRAL/NERN MN ESEWD ACROSS CENTRAL WI AND CENTRAL LOWER MI INITIALLY...AS BOUNDARY LAYER HEATS ACROSS THIS REGION AND AHEAD OF REMAINS OF CURRENT DAKOTAS COMPLEX. DAMAGING GUSTS AND ISOLATED HAIL ARE POSSIBLE. FARTHER W...RELATIVELY STEEP LAPSE RATES ALOFT...VIGOROUS SFC HEATING AND LIFT INVOF BOUNDARY SHOULD OVERCOME STRONG CINH...LEADING TO AFTERNOON/EVENING INITIATION FROM ERN ND ACROSS CENTRAL MN. VERTICAL SHEAR PROFILES WILL BE FAVORABLE FOR SUPERCELLS AND BOW ECHOES IN BOTH REGIMES...ESPECIALLY WITHIN SFC FRONTAL ZONE WHERE BULK SHEAR...VORTICITY...STORM-RELATIVE INFLOW AND SRH ALL SHOULD BE MAXIMIZED. GREATEST AFTERNOON MLCAPES...PERHAPS REACHING 3000-4000 J/KG RANGE...ARE EXPECTED OVER WRN REGIME. EVOLUTION OF SECOND MCS WITH DAMAGING GUSTS AND LARGE HAIL IS POSSIBLE ESEWD ACROSS MN...AND OVERNIGHT INTO WI. ...LOWER GREAT LAKES... WIDELY SCATTERED TO ISOLATED TSTMS MAY DEVELOP ACROSS NRN OH/NWRN PA/WRN NY REGION DURING AFTERNOON...AMIDST STRONG SFC HEATING AND FAVORABLE MOISTURE...WITH LOCALIZED/MRGL SVR POTENTIAL. BETTER ORGANIZED BUT MORE CONDITIONAL SVR THREAT EXISTS IN ASSOCIATION WITH POTENTIAL MCS MOTION INTO THIS AREA...FROM LOWER MI AND/OR SRN ONT. THIS POTENTIAL ALSO MAY BE SUPPORTED BY ANY MCV OR CONVECTIVELY ENHANCED/PRE-EXISTING PERTURBATIONS SUCH AS THAT EVIDENT NOW OVER NWRN MN/NERN SD. SOME PART OF THIS AREA MAY BE ADDED TO CATEGORICAL SLGT RISK AS DIURNAL DESTABILIZATION PATTERNS AND UPSTREAM CONVECTIVE TRENDS WARRANT. ...SWRN CONUS... ISOLATED STRONG-SVR TSTMS MAY DEVELOP THIS AFTERNOON/EVENING OVER THIS REGION...HOWEVER BOTH KINEMATIC AND THERMODYNAMIC PROFILES APPEAR LESS FAVORABLE FOR ORGANIZED SVR EVENT OVER REGION AS A WHOLE. CLOUD DEBRIS AND DEEP-LAYER LAPSE RATE STABILIZATION BY ONGOING ACTIVITY WILL DELAY AIR MASS RECOVERY ESPECIALLY OVER WRN/NRN AZ. POCKETS OF FAVORABLE DESTABILIZATION ARE POSSIBLE ACROSS THIS AREA DURING MID-LATE AFTERNOON...RESULTING IN LOCALIZED STRONG HEATING OF HIGHER TERRAIN AND DEEPLY MIXED BOUNDARY LAYERS ACROSS DESERT AREAS. AREA OF MIDLEVEL NELY FLOW SHOULD WEAKEN...AS WELL AS SHRINK IN BOTH HORIZONTAL AND VERTICAL EXTENT...AS RELATED MID/UPPER LEVEL LOW BECOMES MORE POORLY DEFINED. STILL...A FEW TSTMS MAY FORM OVER HIGHER ELEVATIONS OF NRN AZ AND MOVE SWWD WITH DAMAGING GUSTS BEING MAIN CONCERN. ACROSS SERN AZ/SWRN NM...MORE PROLONGED HEATING IS POSSIBLE...BUT DEEP-LAYER FLOW WILL BE WEAKER WITH MORE WLY COMPONENT ALOFT. SVR POTENTIAL SHOULD BE RATHER SPORADIC AND DISORGANIZED. ...SERN CONUS... SCATTERED TSTMS IN CLUSTERS...WITH ISOLATED DAMAGING WIND OR MARGINALLY SVR HAIL...WILL BE POSSIBLE OVER VERY BROAD SWATH OF SERN STATES. POTENTIAL WILL BE CONCENTRATED AROUND SEA BREEZE FRONTS...MESOSCALE DIFFERENTIAL HEATING BOUNDARIES RELATED TO PRECURSORY CLOUD/PRECIP PATTERNS...AND OUTFLOW INTERSECTIONS. BUOYANCY MAY BE MAXIMIZED ACROSS ERN PIEDMONT/COASTAL PLAIN OF AL...GA AND CAROLINAS. IN THAT CORRIDOR...SUCH BOUNDARIES WILL BE MOST COMMON...ALONG WITH SFC DEW POINTS IN 70S F AND STRONG AFTERNOON HEATING IN RELATIVELY CLOUD-FREE AREAS. MAIN MODE WILL BE MULTICELLULAR AND PULSE IN NATURE BECAUSE OF WEAK DEEP-LAYER FLOW AND LACK OF VERTICAL SHEAR. ...NRN HIGH PLAINS... ELY SFC FLOW COMPONENT N OF SFC FRONT...AND NW OF SFC LOW...WILL ACT TO TRANSPORT MOISTURE INTO ERN MT...AS WELL AS TO ENHANCE DEEP-LAYER SHEAR AND WEAKLY AID IN LOW LEVEL ASCENT. THIS WILL LEAD TO POTENTIAL FOR WIDELY SCATTERED TSTMS BY MID-LATE AFTERNOON AS SFC HEATING AND UPSLOPE LIFT WEAKEN SBCINH. ADVECTION SHOULD YIELD ENOUGH BOUNDARY LAYER MOISTURE TO YIELD FAVORABLE MLCAPES -- 1000-1500 J/KG BASED ON MODIFIED WRF SOUNDINGS -- HOWEVER SUBCLOUD LAYERS STILL WILL BE RELATIVELY DRY AND WELL-MIXED. THIS FAVORS POTENTIAL FOR DAMAGING GUSTS AND HAIL WITH MOST INTENSE CELLS. ..EDWARDS/GRAMS.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 12:45:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 08:45:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291243 SWODY1 SPC AC 291242 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0742 AM CDT SAT JUL 29 2006 VALID 291300Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATER THIS AFTERNOON AND TONIGHT ACROSS THE UPPER MIDWEST AND UPPER GREAT LAKES.... ...SYNOPSIS... LARGE MID/UPPER LEVEL RIDGE IS RE-ESTABLISHING ITSELF FROM THE CENTRAL INTERMOUNTAIN REGION EWD ACROSS MUCH OF THE PLAINS AND MS VALLEY INTO THE GULF COAST STATES. THIS PLACES MAIN BAND OF WESTERLIES FROM THE PACIFIC NORTHWEST STATES NEWD INTO THE NRN ROCKIES AND EXTREME NRN PLAINS THEN SEWD ACROSS THE GREAT LAKES AND NEW ENGLAND. SEVERAL MINOR SHORTWAVE TROUGHS WILL BE EMBEDDED WITHIN THE FLOW FROM MT ENEWD OVER THE RIDGE ACROSS ND THEN SEWD INTO THE UPPER GREAT LAKES DURING THE PERIOD. LATE AFTERNOON AND NIGHTTIME STRONG/SEVERE THUNDERSTORMS WILL OCCUR ON ANTICYCLONIC SIDE OF THE RIDGE AXIS ACROSS THE UPR MS VALLEY AND UPR GREAT LAKES WHERE ENHANCED UVVS AND SHEAR WILL TAKE PLACE. ...UPR MIDWEST INTO THE GREAT LAKES REGION... TWO ROUNDS OF STRONG/SEVERE THUNDERSTORMS HAVE BEEN OCCURRING OVERNIGHT ACROSS PARTS OF MN INTO WI LAYING OUT SEVERAL CONVECTIVELY INDUCED BOUNDARIES ACROSS THE REGION. NEXT SHORTWAVE TROUGH WILL MOVE FROM ERN MT THRU ND INTO NERN MN TONIGHT AFTER 30/00Z. LOW LEVEL FLOW OF 35-40 KT IS EXPECTED FROM SWRN KS INTO SERN ND WHICH SHOULD PLAY IN INITIATION OF NEW CONVECTION ACROSS PARTS OF ERN ND THIS EVENING. THIS COUPLED WITH 45-55 KT OF WLY/NWLY MID LEVEL FLOW WILL ENHANCE DEEP LAYER SHEAR SUPPORTIVE FOR UPDRAFTS THAT WILL BECOME AN MCS OVER ERN ND INTO NWRN MN BY EARLY TONIGHT. AIR MASS ACROSS THE PLAINS WILL BE VERY HOT AND MOIST TODAY AS DEW POINTS WILL REMAIN IN THE UPR 60S/LOW 70S S OF OLD CONVECTIVE BOUNDARY ACROSS EAST CENTRAL ND INTO NWRN WI. MLCAPES OF 2500-3000 J/KG WITH DEEP LAYER SHEAR OF 45-50 KT FORMULATES SIMILAR THERMODYNAMIC AND KINEMATIC PROFILE AS WAS IN PLACE OVER MN THIS MORNING. THUS...EXPECT SCATTERED STRONG/SEVERE THUNDERSTORMS TO DEVELOP THIS EVENING AND TONIGHT FROM ERN ND ESEWD INTO NRN WI AND UPR MI/NRN LWR MI WITH MAIN THREAT BEING DAMAGING WINDS AND SOME HAIL. ...TN VALLEY REGION INTO THE CAROLINAS... NAM AND SREF MODELS INDICATE MID LEVEL TROUGH SHIFTS SEWD FROM KY/TN INTO THE CAROLINAS DURING THE PERIOD. NUMEROUS SEVERE REPORTS OCCURRED YESTERDAY IN THIS SAME REGIME AS ONE TROUGH MOVED THROUGH SRN NEW ENGLAND/MID ATLANTIC STATES AND ANOTHER FEATURE AIDED IN CONVECTIVE DEVELOPMENT IN FAVORABLE SEA BREEZE AREA. TROUGHING COMBINED WITH HEATING OF WARM MOIST AIR MASS WILL PROVIDE FAVORABLE THERMODYNAMICS AND UVVS FOR ANOTHER DAY OF WIDESPREAD PULSE THUNDERSTORMS THROUGH THIS REGION. STEEP SFC-3KM LAPSE RATES RESULTING IN TEMP/DEW POINT SPREAD OF 25-30 DEG F INDICATE THAT SOME OF THIS ACTIVITY COULD PRODUCE WET MICRO BURSTS/DAMAGING WINDS THIS AFTERNOON AND EVENING. ...AREAS OF AZ INTO EXTREME SERN NV... LATEST WATER VAPOR IMAGERY ONCE AGAIN DEPICTS MID/UPPER LEVEL CYCLONIC CIRCULATION OVER THE AZ/NM BORDER INTO WRN NM. THIS IS PULLING NWD MONSOONAL MOISTURE FROM MEXICO INTO NM. THUS...NLY MID LEVEL FLOW IN VICINITY OF MOGOLLON RIM ALONG WITH PRESENCE OF MONSOONAL MOISTURE WILL ONCE AGAIN PROVIDE FAVORABLE SHEAR AND THERMODYNAMICS FOR ISOLATED SEVERE STORMS THIS AFTERNOON AND EARLY TONIGHT. ..MCCARTHY.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 16:17:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 12:17:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291617 SWODY1 SPC AC 291615 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1115 AM CDT SAT JUL 29 2006 VALID 291630Z - 301200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN PORTIONS OF THE NRN PLAINS INTO UPSTATE NY... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE CENTRAL/ERN CAROLINAS... ...NRN PLAINS ACROSS THE GREAT LAKES AND INTO NRN NEW ENGLAND... BROAD AREA OF MODEST NWLY FLOW ALOFT EXPECTED TO CONTINUE ALONG PERIPHERY OF LARGE UPPER RIDGE ACROSS THE NRN/NERN TIER OF THE U.S. TODAY. AT THE SURFACE...SYNOPTIC COLD FRONT NOW EXTENDING ACROSS SRN QUEBEC/ONTARIO WILL SAG SEWD INTO NRN NEW ENGLAND/LOWER GREAT LAKES THIS AFTERNOON. MIDDLE PORTION OF THIS FRONT HAS BEEN REINFORCED BY SEVERAL MCSS OVER THE CENTRAL/WRN GREAT LAKES AND NRN MS RIVER VALLEY AND CONTINUES TO PUSH SWD TOWARDS NRN IL/SRN LOWER MI AT 16Z...WHILE WRN END REMAINS STALLED INTO SWRN MN AND E-W ACROSS FAR NRN SD. LOCATION OF THIS BOUNDARY WILL BE CRUCIAL TO AFTERNOON SEVERE THREAT...ESPECIALLY OVER THE CENTRAL GREAT LAKES...AS DEEP LAYER SHEAR DIMINISHES CONSIDERABLY SOUTH OF THE GREAT LAKES. APPEARS MORE THAN REASONABLE TO EXPECT INCREASE IN SEVERE THREAT AHEAD OF THE FRONT ACROSS CENTRAL/SERN LOWER MI AND SWRN ONTARIO DURING THE EARLY AFTERNOON AS CAP WEAKENS DUE TO HEATING. FORECAST SOUNDINGS INDICATE DEEP LAYER SHEAR WILL BE MARGINAL BUT STILL SUFFICIENT FOR SOME LINEAR/CLUSTER ORGANIZATION IF STORMS CAN INCREASE OVER THIS REGION WITH SFC-6 KM SHEAR AROUND 20 KT. OTHER STORMS WILL LIKELY INCREASE AND ORGANIZE INTO LINES/CLUSTERS NEAR THE COLD FRONT APPROACHING UPSTATE NY AND POSSIBLY NRN PORTIONS OF NEW ENGLAND THIS AFTERNOON WHERE AIR MASS REMAINS QUITE MOIST DESPITE PASSAGE OF WEAK FRONT YESTERDAY. HAVE ADJUSTED SLGT RISK TO ACCOUNT FOR INCREASED SEVERE THREAT ALONG THIS PORTION OF THE FRONT...PRIMARILY IN THE FORM OF DAMAGING WINDS. MORE ROBUST DEVELOPMENT MAY OCCUR LATE TODAY AND THIS EVENING INTO ERN PORTIONS OF THE NRN PLAINS AND NRN MS RIVER VALLEY WHERE VERY STRONG HEATING WITHIN WARM SECTOR AND FOCUSED ASCENT ALONG SLY LLJ OCCUR NEAR THE FRONT. LARGE SCALE FOCUS WILL REMAIN LIMITED...SUGGESTING DEVELOPMENT WILL NEED TO BE DRIVEN BY STRONG HEATING AND LOW LEVEL CONVERGENCE NEAR STALLED BOUNDARY. REGARDLESS...MODELS IN AGREEMENT IN CONVECTIVE DEVELOPMENT WITHIN STRONGLY UNSTABLE AIR MASS OVER SERN ND/NERN SD/WRN MN BY 00Z. SHEAR WILL BE QUITE STRONG...CONSIDERING DEGREE OF INSTABILITY FORECAST...AND WILL SUPPORT SUPERCELLS. ACTIVITY WILL BE CAPABLE OF LARGE HAIL AND DAMAGING WINDS...AND EVEN A FEW TORNADOES IF LOWER 70F SURFACE DEW POINTS CAN SURVIVE STRONG BOUNDARY LAYER MIXING. THIS ACTIVITY WILL LIKELY BUILD INTO ONE OR MORE MCSS DURING THE EVENING WHICH MOVE ESEWD OVERNIGHT. PATTERN REMAINS QUITE FAVORABLE FOR ANOTHER BOW ECHO-MCS DURING THE EVENING/OVERNIGHT ACROSS THE NRN MS RIVER VALLEY AND INTO THE WRN GREAT LAKES. ...CAROLINAS... VWP AT GSP THIS MORNING CONTINUES TO SHOW 30-40 KT WLY WINDS BETWEEN 2-6 KM ASSOCIATED WITH WEAK MID LEVEL CIRCULATION NOW MOVING ACROSS THE SRN APPALACHIANS. IN ADDITION...MORNING SOUNDINGS ALONG THE CAROLINA COAST MAINTAIN RELATIVELY STEEP MID LEVEL LAPSE RATES AND VERTICAL MAXIMUM THETA-E DIFFERENCES FROM 28-35K. INTENSE UPDRAFTS HAVE BEEN QUITE PRODUCTIVE IN PRODUCING DAMAGING MICROBURSTS WITHIN SIMILAR ENVIRONMENT THE PAST TWO DAYS. SLOW MOVING MID LEVEL SYSTEM AND ASSOCIATED INCREASED WLY FLOW ALOFT MAY ADD IMPETUS FOR STRONG TO SEVERE DOWNBURSTS AS STORMS MAY ORGANIZE A BIT MORE TODAY INTO SMALL LINES/CLUSTERS. ...FL... 12Z SOUNDINGS ACROSS THE STATE WILL AGAIN SUPPORT A FEW STRONG TO SEVERE PULSE STORMS TODAY WITH H85-H5 LAPSE RATES AROUND 6.5 C/KM AND H5 TEMP NEAR -8C AT TBW. MARGINALLY SEVERE HAIL SHOULD ACCOMPANY WET-MICROBURST POTENTIAL WITH STRONGER CORES TODAY. PERSISTENT ESELY LOW LEVEL WINDS SHOULD PUSH EAST COAST SEA BREEZE WELL INLAND AND EXPECT GREATER CONCENTRATION OF STORMS/PULSE-SEVERE THREAT TO OCCUR OVER CENTRAL AND WRN PORTIONS OF THE PENINSULA. ...CENTRAL MT INTO NRN HIGH PLAINS... FRONT REMAINS STALLED FROM NERN WY NWWD ACROSS CENTRAL MT THIS MORNING...EAST OF WHICH AIR MASS REMAINS QUITE MOIST WITH 50+F SURFACE DEW POINTS. STRONG HEATING AND ASCENT AHEAD OF SUBTLE SHORTWAVE TROUGH MAY ALLOW SCATTERED HIGH-BASED THUNDERSTORMS TO DEVELOP NEWD ACROSS CENTRAL MT LATER TODAY. STILL QUESTIONABLE HOW MUCH STORMS CAN ROOT INTO COOLER/MORE MOIST SURFACE AIR EAST OF THE FRONT OVER THE NRN HIGH PLAINS THIS EVENING. HOWEVER...WILL MAINTAIN LOW SEVERE PROBABILITIES ACROSS THIS REGION. ...AZ... CLOUDS REMAIN WIDESPREAD NEAR AND SOUTHEAST OF PRIMARY UPPER LEVEL LOW NOW OVER WRN NM THIS MORNING...WHICH SHOULD HINDER HEATING A BIT TODAY. HOWEVER...AIR MASS REMAINS QUITE MOIST AND MAY ONCE AGAIN SUPPORT A FEW STRONGER STORMS TODAY. SHEAR IS A BIT WEAKER THAN YESTERDAY...BUT AN ISOLATED LARGE HAIL/DAMAGING WIND EVENT REMAINS POSSIBLE. ..EVANS/GUYER.. 07/29/2006  From swody1 at goshenarc.org Sat Jul 29 20:09:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 29 Jul 2006 16:09:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 292009 SWODY1 SPC AC 292007 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0307 PM CDT SAT JUL 29 2006 VALID 292000Z - 301200Z ...THERE IS A MDT RISK OF SVR TSTMS LATE AFTERNOON AND EVENING ACROSS NERN SD/SERN ND AND WEST CENTRAL MN... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN PORTIONS OF THE NRN PLAINS INTO MUCH OF NY/WRN VT... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE ERN CAROLINAS... ...INCREASING POTENTIAL FOR SUPERCELLS PRODUCING VERY LARGE DAMAGING HAIL...DAMAGING WINDS AND A FEW TORNADOES ACROSS SERN ND/ NERN SD/WEST CENTRAL MN DURING THE LATE AFTERNOON AND EVENING... ...NRN PLAINS TO GREAT LAKES REGION... EARLY AFTERNOON SURFACE ANALYSIS SHOWED A COLD FRONT MOVING SWD THROUGH THE UPPER GREAT LAKES REGION. THE WRN PORTION OF THIS BOUNDARY SHOULD REMAINED GENERALLY STATIONARY FROM CENTRAL MN INTO SERN ND TO NWRN SD. A CONVECTIVE OUTFLOW BOUNDARY FROM EARLIER MCS HAS STALLED THIS AFTERNOON ACROSS SRN LOWER MI INTO SRN WI/SERN MN TO ALONG THE ERN PART OF THE ND/SD BORDER REGION. A SURFACE LOW WAS ANALYZED IN CENTRAL SD NEAR PIR. WATER VAPOR IMAGERY INDICATED A MID LEVEL SHORT WAVE TROUGH OVER ERN MT. THIS FEATURE IS PROGGED TO TOP THE RIDGE AND TRACK EWD ACROSS ND THIS EVENING REACHING THE UPPER MS VALLEY BY 12Z SUNDAY. ASCENT AHEAD OF THIS IMPULSE APPEARS TO BE AIDING CURRENT THUNDERSTORM DEVELOPMENT ALONG THE WRN PART OF THE ND/SD BORDER IN THE VICINITY OF THE SURFACE FRONT. ADDITIONAL SURFACE HEATING THIS AFTERNOON WITHIN RICH MOISTURE ALONG/S OF SURFACE BOUNDARIES IS EXPECTED TO MAINTAIN A VERY UNSTABLE AIR MASS /MLCAPE UP TO 4000 J/KG IN ERN SD/SWRN MN/ TO 2500-3000 J/KG INTO SWRN GREAT LAKES REGION. SURFACE HEATING AND INCREASING ASCENT AHEAD OF MT IMPULSE ARE EXPECTED TO FURTHER WEAKEN INHIBITION ACROSS NERN SD/SERN ND INTO WRN MN FOR THUNDERSTORMS TO RAPIDLY DEVELOP BY LATE AFTERNOON. STRONG EFFECTIVE BULK SHEAR VALUES /40-50 KT/ AND INCREASING LOW LEVEL SHEAR ACROSS THE MODERATE RISK AREA WILL SUPPORT SUPERCELLS PRODUCING VERY LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES. THIS ACTIVITY SHOULD GROW UPSCALE INTO ONE OR MORE MCSS ACROSS THE NRN MS VALLEY/WRN GREAT LAKES REGION AS THE MT IMPULSE APPROACHES AND LOW LEVEL CONVERGENCE INCREASES ALONG THE FRONT IN CENTRAL MN PER STRENGTHENING SSWLY LLJ. CAPE/SHEAR VALUES ARE EXPECTED TO REMAIN FAVORABLE FOR SEVERE STORMS TO CONTINUE INTO THE OVERNIGHT PERIOD WITH THIS MCS ACTIVITY...POTENTIALLY EVOLVING INTO ANOTHER BOWING SYSTEM. ...PART OF THE NERN STATES /ERN EXTENT OF SLIGHT RISK/... COLD FRONT...CURRENTLY EXTENDING FROM SRN QUEBEC INTO SERN ONTARIO...WILL CONTINUE TO SPREAD ESEWD INTO THE NERN STATES THIS FORECAST PERIOD. MODERATELY UNSTABLE AIR MASS AHEAD OF THIS FRONT WILL CONTINUE TO MAINTAIN FAVORABLE ENVIRONMENT FOR THUNDERSTORM DEVELOPMENT AS ASCENT SPREADS EWD AHEAD OF A SHORT WAVE TROUGH... NOW CENTERED OVER LAKE HURON. DEEP LAYER SHEAR OF 30-40 KT SUGGESTS A CONTINUED POTENTIAL FOR BOWING LINE STRUCTURES AND SUPERCELLS. ...ERN CAROLINAS... THUNDERSTORMS WILL CONTINUE TO DEVELOP WITHIN MODERATELY UNSTABLE AIR MASS ACROSS THE ERN CAROLINAS INTO ERN GA AS ASCENT SPREADS EWD AHEAD OF SLOW MOVING MID LEVEL CIRCULATION...NOW LOCATED OVER WRN NC/NWRN SC. DESPITE SUFFICIENT INSTABILITY...GENERALLY WEAK DEEP LAYER SHEAR SHOULD PROMOTE A PULSE STORM MODE...WITH DAMAGING DOWNBURST WINDS THE PRIMARY THREAT INTO THE EARLY EVENING. ..PETERS.. 07/29/2006  From swody1 at goshenarc.org Sun Jul 30 20:05:57 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 30 Jul 2006 16:05:57 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 302005 SWODY1 SPC AC 302003 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0303 PM CDT SUN JUL 30 2006 VALID 302000Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER NRN PLAINS TO OH VALLEY... ...OH VALLEY... AIR MASS ACROSS THE OH VALLEY EXPECTED TO RANGE FROM MODERATELY TO VERY UNSTABLE INTO THE EARLY EVENING. RECENT TRENDS IN ONGOING MCS OVER SRN GREAT LAKES REGION SUGGEST GREATER ESEWD MOVEMENT TO CONTINUE AS INDICATED OVER SERN LOWER MI ATTM. SOME INTENSIFICATION POSSIBLE IN THE WIND POTENTIAL WITH THE SYSTEM AS IT ENCOUNTERS INCREASINGLY UNSTABLE AIR MASS OVER NRN/NERN OH WITH MCS POTENTIALLY REACHING PARTS OF WRN PA/WRN NY BY EARLY EVENING. STORMS SHOULD THEN WEAKEN AS THEY ENCOUNTER LESS FAVORABLE CONDITIONS AS AIR MASS BEGINS TO STABILIZE WITH LOSS OF DAYTIME HEATING. ALTHOUGH THE SWRN FLANK OF THE MCS IS MOVING MORE SLOWLY SWD THROUGH NRN IND/NRN IL AND NERN IA...A VERY UNSTABLE AIR MASS ALONG/S OF THIS REGION AND 30-35 KT EFFECTIVE BULK SHEAR SUPPORTS A CONTINUED THREAT FOR SEVERE STORMS INTO THE EVENING. ...NRN PLAINS EWD TO WRN GREAT LAKES... SURFACE LOW WILL CONTINUE TO MOVE EWD ACROSS THE DAKOTAS THIS FORECAST PERIOD...WHILE WARM FRONT CONTINUES TO LIFT NWD THROUGH ERN ND/NRN MN. A VERY WARM TO HOT AND UNSTABLE AIR MASS /MLCAPE EXCEEDING 4000 J/KG ACROSS MUCH OF MN/ HAS DEVELOPED IN THE WARM SECTOR EAST OF THE SURFACE LOW. WARM SECTOR IS EXPECTED TO REMAIN CAPPED THRU MUCH OF THE AFTERNOON AS INDICATED BY RECENT STRONG CAPPING PER TAMDAR SOUNDINGS AT FAR/BJI. THUS...AFTERNOON/EVENING SEVERE THREAT SHOULD BE LIMITED TO PARTS OF NERN MN/WRN U.P. OF MI AS ELEVATED STORMS CONTINUE TO DEVELOP ON COOL SIDE OF CONVECTIVE OUTFLOW WHERE SHEAR/CAPE VALUES REMAIN FAVORABLE FOR SOME SEVERE. OVERNIGHT AS THE LOW LEVEL JET INCREASES TO 40-50 KT IN WARM SECTOR AHEAD OF SURFACE LOW...SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP VICINITY BOUNDARY IN ND EWD WITH POSSIBILITY FOR ONE OR MORE MCS/S TRACKING EWD VICINITY THE INTERNATIONAL BORDER FROM ND TO LS. DAMAGING WINDS WOULD LIKELY ACCOMPANY THE MCS/S GIVEN BOTH LARGE AMOUNT OF INSTABILITY AND STEEP LAPSE RATES. ...NRN HIGH PLAINS... UPPER SHORT WAVE TROUGH...NOW LOCATED OVER SRN BRITISH COLUMBIA/ PACIFIC NW...WILL TRACK NEWD OVER NRN ROCKIES REACHING SASKATCHEWAN BY 12Z MONDAY. AS THIS OCCURS...60 METER HEIGHT FALLS ARE EXPECTED INTO THE NRN PLAINS TONIGHT WITH RESULTANT EWD SHIFT OF RIDGE CREST TOWARD THE WRN GREAT LAKES. ASCENT AHEAD OF THIS TROUGH SHOULD SUPPORT AN INCREASING POTENTIAL FOR THUNDERSTORMS OVER THE HIGHER TERRAIN OF CENTRAL MT AND/OR ALONG A COLD FRONT PROGRESSING EWD ACROSS MT. 60 PLUS KT MID LEVEL WIND MAX ACCOMPANYING UPPER TROUGH ACROSS MT THIS EVENING SUGGESTS SEVERE STORMS INCREASINGLY LIKELY...MAINLY AS ACTIVITY MOVES EWD ENCOUNTERING GREATER INSTABILITY CLOSER TO THE MT/ND BORDER THIS EVENING. ..PETERS.. 07/30/2006  From swody1 at goshenarc.org Mon Jul 31 00:52:00 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 30 Jul 2006 20:52:00 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 310052 SWODY1 SPC AC 310050 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0750 PM CDT SUN JUL 30 2006 VALID 310100Z - 311200Z ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT FROM ND INTO THE UPPER OH VALLEY... ...ND INTO THE UPPER GREAT LAKES... EVENING WATER VAPOR IMAGERY SHOWS SHORT WAVE TROUGH LIFTING NEWD THROUGH ERN MT WITH AN ASSOCIATED BELT OF 40-45 KT MID-LEVEL FLOW SPREADING EWD ACROSS ND INTO THE RED RIVER VALLEY. AIR MASS ALONG AND S OF SURFACE LOW /NEAR BIS/ AND ATTENDANT SURFACE FRONT EXTENDING ENEWD INTO NWRN MN HAS ONCE AGAIN BECOME QUITE HOT WITH TEMPERATURES WARMING TO WELL OVER 100 F OVER CNTRL SD INTO S-CNTRL ND. STRONG CAPPING APPEARS TO HAVE INHIBITED SURFACE-BASED STORM DEVELOPMENT THUS FAR EXCEPT OVER FAR NERN MT IN CLOSER PROXIMITY TO SHORT WAVE TROUGH /REF. MCD 1680 FOR ADDITIONAL SHORT TERM GUIDANCE/. FARTHER TO THE E...REMNANT OUTFLOW BOUNDARY FROM SATURDAY NIGHT-EARLY SUNDAY MCS EXTENDS FROM INTERSECTION WITH SYNOPTIC FRONT OVER N-CNTRL MN SEWD THROUGH WRN WI INTO N-CNTRL IL. AGAIN TONIGHT...00Z MPX SOUNDINGS INDICATES THAT THE STRONGEST INSTABILITY RESIDES ALONG AND JUST TO THE S OF THIS OUTFLOW BOUNDARY OVER CNTRL/SRN MN WHERE MLCAPES REMAIN AROUND 3000-4000 J/KG. LATEST SHORT TERM MODEL GUIDANCE SUGGESTS THAT TSTMS /MAINLY ELEVATED/ WILL INCREASE IN COVERAGE OVERNIGHT N OF FRONTAL ZONE ACROSS NRN PARTS OF ND/MN...EVENTUALLY EWD INTO LAKE SUPERIOR AND THE UP OF MI AS LOW-LEVEL WAA/ISENTROPIC UPGLIDE INCREASE N OF FRONT AND OUTFLOW BOUNDARY. REGIONAL VWPS INDICATE THAT SUFFICIENT VERTICAL SHEAR WILL EXIST FOR SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. GREATEST POTENTIAL FOR A TORNADO WOULD EXIST WITH ANY NEAR SURFACE BASED SUPERCELLS THAT CAN MATURE NEAR SYNOPTIC FRONT/OUTFLOW BOUNDARY INTERSECTION OVER NWRN/N-CNTRL MN WHERE LOW-LEVEL SHEAR IS MAXIMIZED. POTENTIAL FOR UPSCALE GROWTH INTO AN MCS WILL EXIST LATE TONIGHT OVER THE ARROWHEAD/LAKE SUPERIOR/UP OF MI WITH ANY ASSOCIATED WIND THREAT DEVELOPING SEWD INTO NRN WI AND PERHAPS LOWER MI. ...UPPER OH VALLEY... CLUSTERS OF TSTMS ARE IN PROGRESS OVER E-CNTRL OH/W-CNTRL PA WITHIN MOIST AND MODERATELY UNSTABLE AIR MASS WITH MLCAPES OF AROUND 2000 J/KG /PER 00Z PIT SOUNDING/. SHORT WAVE TROUGH OVER LOWER MI INTO LAKE ERIE IS FORECAST TO CONTINUE SEWD TONIGHT...PROVIDING BACKGROUND FORCING TO SUSTAIN ACTIVITY CONVECTION INTO THE OVERNIGHT HOURS. IT APPEARS THE GREATEST POTENTIAL FOR ADDITIONAL STRONG TO SEVERE TSTMS WILL EXIST ALONG THE WRN FLANK OF ONGOING TSTM COMPLEX WHICH WILL BE MAINTAINED BY LOW-LEVEL WAA ALONG MODEST WLY LLJ. VERTICAL SHEAR IS NOT PARTICULARLY STRONG...THOUGH THE POTENTIAL WILL EXIST FOR LOCALLY DAMAGING WINDS...ESPECIALLY IF A COLD POOL CAN ORGANIZE. ...CNTRL GULF COAST... LARGE TSTM COMPLEX HAS EVOLVED OVER SERN MS/SWRN AL WITHIN A MOIST AND MODERATELY UNSTABLE AIR MASS WITH MLCAPES OF 1000-2000 J/KG. THIS SYSTEM APPEARS TO HAVE ORGANIZED A COLD POOL AND SOME THREAT OF LOCALLY DAMAGING WINDS WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AS STORMS MOVE/DEVELOP SWD TOWARD THE COAST. ...AZ... TSTM CLUSTERS OVER SRN COCONINO AND NAVAJO COUNTIES IN NRN AZ APPEAR TO HAVE SOME ORGANIZATION AS THEY MOVE GENERALLY SWD AT 10-15 KT. ENVIRONMENT REMAINS RELATIVELY MOIST AND MODERATELY UNSTABLE...WHICH SHOULD MAINTAIN STORMS SWD TOWARD THE LOWER DESERTS LATER THIS EVENING. ARE VWPS AND 00Z SOUNDINGS INDICATE THAT VERTICAL SHEAR IS QUITE WEAK WHICH SHOULD LIMIT THE OVERALL SEVERE THREAT. STILL...LOCALLY DAMAGING WINDS WILL REMAIN POSSIBLE WITH MOST INTENSE STORMS. ..MEAD.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 05:40:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 01:40:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 310540 SWODY1 SPC AC 310538 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1238 AM CDT MON JUL 31 2006 VALID 311200Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE UPPER MS VALLEY INTO UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF UPSTATE NY INTO WRN NEW ENGLAND... ...SYNOPSIS... PROGRESSIVE LARGE-SCALE PATTERN IS FORECAST FROM THE GREAT BASIN AND PACIFIC NW EWD ACROSS SRN CANADA AND THE NRN TIER OF STATES INTO NEW ENGLAND. WITHIN THIS PATTERN...SHORT WAVE TROUGH NOW OVER FAR ERN MT/WRN ND WILL LIFT NEWD ACROSS SRN MANITOBA INTO ONTARIO AHEAD OF STRONGER IMPULSE SHIFTING EWD THROUGH THE PRAIRIE PROVINCES. MEANWHILE TO THE W...SHORT WAVE WILL MOVE EWD FROM THE ERN PACIFIC INTO THE PACIFIC NW AND GREAT BASIN. IN THE LOW-LEVELS...SURFACE COLD FRONT FROM THE RED RIVER VALLEY SWWD INTO THE CNTRL HIGH PLAINS WILL SHIFT EWD THROUGH THE PERIOD INTO THE UPPER GREAT LAKES...FOCUSING STRONG TO POTENTIALLY SEVERE STORMS THIS AFTERNOON INTO TONIGHT. ...UPPER GREAT LAKES/UPPER MS VALLEY... MCS CURRENTLY EVOLVING OVER NERN ND/NWRN MN IS EXPECTED TO BE ONGOING AT THE ONSET OF THE FORECAST PERIOD OVER PORTIONS OF N-CNTRL MN INTO THE ARROWHEAD REGION...DRIVEN LARGELY BY STRONG LOW-LEVEL WAA ASSOCIATED WITH SWLY LLJ EXTENDING FROM THE CNTRL PLAINS INTO UPPER GREAT LAKES. LATEST MODEL GUIDANCE SUGGESTS THAT THE MAJORITY OF THIS NOCTURNAL CONVECTION WILL MOVE/DEVELOP NEWD INTO SRN ONTARIO TODAY WITH THE SRN FLANK POSSIBLY AFFECTING LOCATIONS AS FAR S AS THE U.P. WITH THE PRIMARY THREAT BEING DAMAGING WINDS. ADDITIONAL STORMS WILL BE POSSIBLE THIS AFTERNOON ALONG COLD FRONT FROM NRN MN SWWD INTO ERN SD WHERE STEEP LAPSE RATES AND MOIST BOUNDARY LAYER CONDITIONS /DEWPOINTS OF 65-75 F/ WILL CONTRIBUTE TO MLCAPES OF 1500-3000 J/KG. WHILE THE STRONGER LARGE-SCALE FORCING WILL GRADUALLY SHIFT NEWD INTO ONTARIO...SUSTAINED LOW-LEVEL CONVERGENCE AND DAYTIME HEATING SHOULD BE SUFFICIENT TO OVERCOME CAP. STRONGEST MID-LEVEL WIND FIELDS /45-55 KTS AT 500 MB/ AND RESULTANT VERTICAL SHEAR ARE FORECAST ACROSS NRN MN...ALONG SRN PERIPHERY OF SHORT WAVE TROUGH MOVING THROUGH MANITOBA/WRN ONTARIO WHERE A FEW SUPERCELLS CAPABLE OF MAINLY DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE. FARTHER S INTO SD...BOTH SHEAR AND INSTABILITY WILL BE WEAKER...THOUGH MULTICELLS WITH LOCALLY STRONG WIND GUSTS AND SOME SEVERE HAIL WILL BE POSSIBLE. ...NY INTO WRN NEW ENGLAND... PERSISTENT SWLY LLJ FROM THE CNTRL PLAINS THROUGH THE GREAT LAKES INTO SWRN ONTARIO/SWRN QUEBEC IS FORECAST TO MAINTAIN A FEED OF A MOIST AND MODERATELY UNSTABLE AIR INTO TSTM CLUSTERS/MCSS THAT ARE EXPECTED TO PERSIST ACROSS SRN ONTARIO INTO SWRN QUEBEC. THESE STORMS MAY BEGIN TO TURN MORE SEWD LATE TONIGHT INTO PORTIONS OF UPSTATE NY AND WRN NEW ENGLAND AS ACTIVITY SHIFTS E OF MEAN MID-LEVEL RIDGE AXIS. FORECAST SOUNDINGS INDICATE THAT INSTABILITY WILL REMAIN MARGINAL...THOUGH RELATIVELY STRONG UNIDIRECTIONAL WIND PROFILES WILL BE SUPPORTIVE OF DAMAGING WIND GUSTS. ...CNTRL/SRN HIGH PLAINS... STEEP LAPSE RATES ARE FORECAST TO DEVELOP TODAY AHEAD OF COLD FRONT MOVING SWD THROUGH THE CNTRL HIGH PLAINS...CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. VERTICAL SHEAR WILL REMAIN QUITE WEAK...THOUGH THE STEEP LAPSE RATES /ESPECIALLY IN THE LOW-LEVELS/ WILL BE SUPPORTIVE OF A FEW STRONG TO SEVERE STORMS CAPABLE OF MAINLY STRONG WIND GUSTS. ...CNTRL/ERN NV... ENVIRONMENT IS FORECAST TO BECOME INCREASINGLY SUPPORTIVE OF TSTMS THIS AFTERNOON INTO EVENING AS FORCING FOR ASCENT ASSOCIATED WITH APPROACHING MID-LEVEL TROUGH COUPLED WITH DAYTIME HEATING CONTRIBUTES TO STEEP LAPSE RATES AND MARGINAL INSTABILITY. DESPITE THIS MARGINAL INSTABILITY...VERTICAL SHEAR WILL BE QUITE STRONG...AND GIVEN THE INCREASED LARGE-SCALE FORCING...POTENTIAL WILL EXIST FOR A FEW ORGANIZED STORMS CAPABLE OF SEVERE HAIL AND LOCALLY DAMAGING WINDS. ..MEAD/GRAMS.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 12:55:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 08:55:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 311256 SWODY1 SPC AC 311254 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT MON JUL 31 2006 VALID 311300Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPR MS VLY AND UPR GRT LKS... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF UPSTATE NY AND WRN NEW ENGLAND... ...SYNOPSIS... DOMINANT MS VLY UPR RIDGE WILL EXPAND E AND SLIGHTLY N INTO THE UPR OH VLY/MID ATLANTIC REGION THIS PERIOD AS SHORTWAVE TROUGH NOW ENTERING SASKATCHEWAN CONTINUES E INTO WRN ONTARIO. FARTHER W... DISTURBANCE NOW NEARING THE NRN CA CST SHOULD REACH THE NRN GRT BASIN BY 12Z TUESDAY. COLD FRONT ACCOMPANYING SASKATCHEWAN TROUGH...NOW EXTENDING FROM NE ND INTO NW NEB LIKELY WILL CONTINUE ONLY SLOWLY SE INTO THE CNTRL PLNS ...BUT SHOULD PROGRESS STEADILY E ACROSS THE UPR MS VLY/UPR GRT LKS BY TONIGHT/EARLY TUESDAY. ...UPR MS VLY/UPR GRT LKS... CONVECTIVE SYSTEMS NOW OVER WRN LK SUPERIOR AND THE ERN U.P. OF MI SHOULD CONTINUE GENERALLY ESE INTO ONTARIO LATER THIS MORNING... AHEAD OF SLOWLY EXPANDING UPR RIDGE. STRONG LOW-LEVEL WARM ADVECTION FROM THE WEST MAY SUPPORT BACK-BUILDING/REGENERATIVE ACTIVITY ON THE SWRN FLANKS OF THESE SYSTEMS. SOME OF THE STORMS COULD AFFECT NRN AND ERN PARTS OF THE U.P...AND POSSIBLY EXTREME NRN LWR MI...WITH LOCALLY DAMAGING WIND. BUT THE BULK OF THIS SLIGHTLY ELEVATED ACTIVITY SHOULD REMAIN IN CANADA. FARTHER W...A BAND OR TWO OF ELEVATED STORMS MAY PERSIST THROUGH MIDDAY IN POST-FRONTAL/POST CONVECTIVE OUTFLOW ENVIRONMENT IN NRN MN/ERN ND. RELATIVELY WARM MID LEVEL TEMPERATURES AND WEAK LARGE SCALE ASCENT SHOULD LIMIT POTENTIAL FOR SUSTAINED STORMS WITH HAIL. LATER TODAY...EXPECT THAT SURFACE HEATING AND WEAK ASCENT S OF PASSING TROUGH WILL INITIATE SURFACE-BASED STORMS ALONG COLD FRONT IN NRN/CNTRL MN AND THE ERN DAKOTAS. WARM MID LEVEL TEMPERATURES WILL CONTINUE TO LIMIT DEGREE OF DIURNAL DESTABILIZATION. BUT VERY WARM...FAIRLY MOIST AND DEEPLY-MIXED BOUNDARY LAYER SHOULD YIELD MLCAPE OF 1500-3000 J/KG. UNIDIRECTIONAL MID LEVEL WSWLY FLOW ON SRN FRINGE OF CANADIAN TROUGH SHOULD INCREASE TO AROUND 50 KTS ACROSS NRN MN...AND TO AOA 30 KTS IN ERN SD/SRN MN. DEEP LAYER OF LARGELY UNIDIRECTIONAL FLOW...HI PWS AND DEEP MIXED LAYERS ALL SUGGEST POTENTIAL FOR ORGANIZATION INTO LINES/CLUSTERS...WITH EMBEDDED SUPERCELLS SUPPORTING BOWING SEGMENTS WITH HIGH WINDS AND POSSIBLY HAIL. POTENTIAL FOR SUSTAINED SEVERE SHOULD DECREASE WITH SWD EXTENT...BUT MAY CONTINUE INTO TONIGHT EWD INTO WI/UPR MI. ...NY/NEW ENGLAND... EWD EXPANSION OF CNTRL STATES RIDGE WILL ENHANCE WARM ADVECTION ACROSS SRN ONTARIO AND THE ST LAWRENCE RVR VLY LATER TODAY THROUGH EARLY TUESDAY. THIS SHOULD SUSTAIN TSTM CLUSTERS/MCSS THAT WILL AFFECT SRN ONTARIO LATER TODAY. THIS ACTIVITY MAY BEGIN TO FORWARD-PROPAGATE SE INTO PARTS OF UPSTATE NY AND WRN NEW ENGLAND LATE TONIGHT/EARLY TUESDAY AS DOWNSTREAM BOUNDARY LAYER WARMS/ MOISTENS. WHILE FORECAST SOUNDINGS INDICATE THAT INSTABILITY WILL REMAIN MARGINAL...RELATIVELY STRONG UNIDIRECTIONAL DEEP WIND FIELDS MAY SUPPORT LOCALLY DAMAGING WINDS. ...CNTRL/SRN HIGH PLAINS... STEEP LOW LEVEL LAPSE RATES WILL DEVELOP WITH AFTERNOON HEATING INVOF COLD FRONT LEE TROUGH SETTLING S/SE ACROSS THE CNTRL HIGH PLAINS. WHILE VERTICAL SHEAR WILL REMAIN WEAK...DEEPLY-MIXED ENVIRONMENT WITH VERY WARM SURFACE TEMPERATURES MAY SUPPORT A FEW PULSE STORMS WITH HIGH WIND. ...CNTRL/ERN NV... ENVIRONMENT MAY SUPPORT A FEW STRONG TSTMS THIS AFTERNOON AND EVENING AS FORCING FOR ASCENT WITH NRN CA TROUGH AND DAYTIME HEATING DESTABILIZE REGION. WHILE INSTABILITY LIKELY WILL REMAIN FAIRLY MARGINAL /SBCAPE AROUND 500 J PER KG/...VERTICAL SHEAR WILL STRENGTHEN AND MAY SUPPORT DEVELOPMENT OF A FEW ORGANIZED STORMS CAPABLE OF DAMAGING WIND AND POSSIBLY MARGINALLY SEVERE HAIL. ..CORFIDI/GRAMS.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 16:22:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 12:22:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 311622 SWODY1 SPC AC 311620 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT MON JUL 31 2006 VALID 311630Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS UPPER GREAT LAKES AND UPPER MS VALLEY... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF UPSTATE NY AND WRN NEW ENGLAND... ...SYNOPSIS... WARM UPPER RIDGE SHIFTS EWD ACROSS GREAT LAKES AS A VIGOROUS SYSTEM TRACKS WELL N OF CONUS ACROSS SCENTRAL CANADA. IN THE WESTERN U.S. A BROAD TROUGH MOVES INTO NRN INTERMOUNTAIN REGION AS WEAK UPPER CIRCULATION THAT HAS RESIDED OVER THE WEEKEND IN NM BEGINS TO LIFT SLOWLY NEWD INTO CENTRAL HIGH PLAINS. COLD FRONT TRAILING SWWD FROM STRONG CANADIAN SYSTEM THRU ERN ND TO ERN CO WILL PUSH STEADILY EWD TO UPPER GREAT LAKES BY LATER TONIGHT STRETCHING SWWD ACROSS NEB TO SERN CO. VERY MOIST AIR MASS BOTH FROM SWLY FLOW AHEAD OF NM UPPER SYSTEM AND LARGE AREA OF GULF MOISTURE ALREADY IN PLACE COVERS MUCH OF REGION FROM COLD FRONT TO APPALACHIANS. ...GREAT LAKES ... THE VERY WARM MID LEVEL TEMPERATURES SPREADING EWD WITH UPPER RIDGE WILL LIMIT SEVERE STORM POTENTIAL AHEAD OF COLD FRONT EVEN WITH ABUNDANT MOISTURE...INSTABILITY AND A FAVORABLY SHEARED ENVIRONMENT CURRENTLY IN PLACE ACROSS THE UPPER GREAT LAKES. OUTFLOW BOUNDARY THAT CURRENTLY EXTENDS WWD FROM CONVECTIVE COMPLEX NRN LH WOULD BE A FOCUS OF SURFACE BASED THUNDERSTORMS NRN LWR MI THIS AFTERNOON AS AIR MASS ALREADY VERY UNSTABLE AND WEAKLY CAPPED. HOWEVER WITH WARMER AIR ALOFT SPREADING EWD SEVERE POTENTIAL SHOULD DIMINISH BY EVENING. UPSTREAM OVER MN AND NRN WI STRONG HEATING WILL WEAKEN CAP SUFFICIENTLY TO ALLOW THUNDERSTORMS TO INITIATE BY MID/LATE AFTERNOON AS MLCAPES CLIMB TO NEAR 2000 J/KG. HOWEVER WITH VERY WARM MID LEVELS...SEVERE THUNDERSTORM POTENTIAL WILL BE LIMITED TO DOWNBURSTS WITH STEEP LOW LEVEL LAPSE RATES AND ONLY A MARGINAL SEVERE HAIL THREAT. ...NY/VT... HAVE CONTINUED A CONDITIONAL LOW END SEVERE THREAT FOR TONIGHT FOR POTENTIAL OF MCS RIDING ACROSS UPR RIDGE AND TRACKING SEWD INTO NRN NY AND VT. WHILE DEEP LAYER SHEAR OF 40KT WOULD SUPPORT A SEVERE THREAT THE INSTABILITY IS CERTAINLY A CONCERN GIVEN THE WARM 500 MB TEMPERATURES AND LAPSE RATES OF 6C/KM OR LESS. WILL CONTINUE PRIMARILY A CONDITIONAL WIND DAMAGE THREAT FOR MCS OCCURRENCE AFTER 00Z. ..HALES/GUYER.. 07/31/2006  From swody1 at goshenarc.org Mon Jul 31 20:00:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 31 Jul 2006 16:00:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 312000 SWODY1 SPC AC 311958 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT MON JUL 31 2006 VALID 312000Z - 011200Z ...THERE IS A SLGT RISK OF SVR TSTMS UPPER MIDWEST/UPPER GREAT LAKES... ...THERE IS A SLGT RISK OF SVR TSTMS UPSTATE NY AND WESTERN NEW ENGLAND... ...GREAT LAKES/UPPER MIDWEST INTO CENTRAL PLAINS... WATER VAPOR IMAGERY FEATURES FAIRLY POTENT SHORTWAVE TROUGH MOVING EASTWARD ACROSS SASKATCHEWAN/MANITOBA AT MID AFTERNOON...WITH AN ASSOCIATED COLD FRONT EXTENDING FROM NORTH CENTRAL MN INTO WESTERN NEB. GIVEN THE DEGREE OF CAPPING/WEAK VERTICAL SHEAR IN THE WARM SECTOR...THE MAIN SEVERE POTENTIAL WILL LIKELY BE RIGHT ALONG AND/OR IN THE IMMEDIATE COOL SIDE OF THE SURFACE COLD FRONT. ALTHOUGH SOME HAIL IS POSSIBLE...WARM MID LEVEL TEMPERATURES SUGGEST THE PRIMARY SEVERE THREAT WILL BE POTENTIALLY DAMAGING DOWNBURSTS WITHIN A RATHER UNSTABLE AIRMASS. THE MORE ORGANIZED SEVERE POTENTIAL WILL BE ACROSS MN/FAR EASTERN SD INTO NORTHWEST WI/WESTERN U.P. OF MICH THROUGH THIS EVENING...ALTHOUGH AN ISOLATED SEVERE THREAT MAY EXIST AS FAR SOUTHWEST AS THE CENTRAL HIGH PLAINS. ...UPSTATE NY AND WESTERN PORTIONS OF NEW ENGLAND... POTENTIAL WILL EXIST FOR ONE OR MORE SMALL MCS/S TO ROUND THE RIDGE FROM EASTERN ONTARIO/FAR SOUTHERN QUEBEC INTO UPSTATE NY AND WESTERN PORTIONS OF NORTHERN NEW ENGLAND LATER THIS EVENING/OVERNIGHT. AHEAD OF THIS POSSIBLE ACTIVITY...AN INCREASINGLY MOIST/UNSTABLE AIRMASS WILL CONTINUE TO ADVECT INTO THE REGION THROUGH TONIGHT...WITH EXISTING FLOW FIELDS/VERTICAL SHEAR OF 40-45 KTS CONDITIONALLY SUPPORTIVE OF ORGANIZED STORMS/MCS MAINTENENCE. EVEN SO...THE TIME OF DAY/MODEST DEGREE OF INSTABILITY AND MILD MID LEVEL TEMPERATURES MAY TEND TO LIMIT THE OVERALL THREAT. PRIMARY HAZARD WOULD BE DAMAGING WIND GUSTS...WITH SOME HAIL POSSIBLE AS WELL. ..GUYER/HART.. 07/31/2006