From swody1 at goshenarc.org Sun Oct 1 05:58:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 01:58:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 010558 SWODY1 SPC AC 010556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT SUN OCT 01 2006 VALID 011200Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... SHARP UPPER TROUGH WILL CONTINUE MOVING EWD ACROSS THE ERN CONUS...WHILE FLATTER/LESS AMPLIFIED PATTERN PREVAILS ACROSS THE REMAINDER OF THE CONUS. AT THE SURFACE...A WEAK LOW IS FORECAST OVER THE LOWER GREAT LAKES REGION THROUGH THE FIRST HALF OF THE PERIOD...WHILE AN ASSOCIATED/OCCLUDED FRONT SHIFTS ACROSS SRN NEW ENGLAND. MEANWHILE...A COLD FRONT -- EXTENDING FROM A SURFACE LOW OVER MANITOBA -- IS FORECAST TO MOVE SEWD ACROSS THE NRN PLAINS. ...PORTIONS OF THE MID-ATLANTIC INTO SRN NEW ENGLAND... MODELS HINT THAT WEAK SURFACE-BASED INSTABILITY MAY BRUSH THE SRN NEW ENGLAND COAST EARLY IN THE PERIOD...AS TRIPLE POINT SHIFTS EWD ACROSS THIS REGION AND INTO THE ATLANTIC. THOUGH THIS SCENARIO REMAINS UNCERTAIN...FAVORABLY STRONG/VEERING FLOW WITH HEIGHT COULD SUPPORT A BRIEF TORNADO -- PRESUMING SURFACE-BASED INSTABILITY EXTENDS INLAND. MORE LIKELY SEVERE WEATHER THREAT HOWEVER MAY OCCUR LATER...AS DAYTIME HEATING BENEATH COLD AIR ALOFT ASSOCIATED WITH UPPER TROUGH YIELDS WEAK DESTABILIZATION. THOUGH DEEP-LAYER SHEAR WILL NOT BE PARTICULARLY STRONG...POCKETS OF INSTABILITY SUPPORTIVE OF A FEW STRONGER UPDRAFTS COULD EVOLVE FROM THE CHESAPEAKE BAY/ERN PA/SERN NY EWD ACROSS SRN NEW ENGLAND DURING THE AFTERNOON. A LOW-PROBABILITY THREAT FOR MARGINAL HAIL MAY ACCOMPANY THE STRONGER UPDRAFTS...BUT ANY THREAT SHOULD DIMINISH QUICKLY THROUGH THE EVENING...AS AIRMASS STABILIZES AND THE TROUGH AXIS SHIFTS OFF THE MID-ATLANTIC COAST. ...NRN IL/SRN WI AND VICINITY... NOCTURNAL STORM DEVELOPMENT APPEARS LIKELY AS SWLY LOW-LEVEL JET -- AHEAD OF SEWD-MOVING COLD FRONT -- SHIFTS EWD INTO THIS REGION AND INTENSIFIES. ASSOCIATED WARM ADVECTION ABOVE A STABLE BOUNDARY LAYER SHOULD YIELD SUFFICIENT ELEVATED INSTABILITY FOR A FEW STRONGER STORMS...AIDED BY 30 KT WLY FLOW FORECAST AT MID-LEVELS. GIVEN THE POTENTIAL FOR A FEW STRONGER STORMS...WILL MAINTAIN A LOW-PROBABILITY THREAT FOR HAIL. ..GOSS.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 12:45:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 08:45:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011244 SWODY1 SPC AC 011243 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0743 AM CDT SUN OCT 01 2006 VALID 011300Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...NJ TO SRN NEW ENGLAND TODAY... A DEEP MID LEVEL TROUGH OVER THE CENTRAL APPALACHIANS WILL MOVE EWD TO OFF THE SRN NEW ENGLAND AND MID ATLANTIC COASTS BY EARLY TONIGHT. A BAND OF RAIN/EMBEDDED THUNDERSTORMS WILL OVERSPREAD SRN NEW ENGLAND TODAY WITH THE WARM CONVEYOR BELT WHICH PRECEDES THE MID LEVEL WAVE. DESPITE THE STRONGER VERTICAL SHEAR...INSTABILITY WILL BE LIMITED UNTIL THE STEEPER LOW-MID LEVEL LAPSE RATES /6.5-7 C/KM/ ARRIVE WITH THE MID LEVEL COLD POOL /-22 C AT 500 MB/...LARGELY IN THE WAKE OF THIS PRECIPITATION BAND. BOUNDARY LAYER DEWPOINTS OF 56-62 F AND DAYTIME TEMPERATURES IN THE 60S WILL COMBINE WITH THE MODEST LAPSE RATES TO SUPPORT WEAK SURFACE-BASED INSTABILITY BY EARLY AFTERNOON /SBCAPE OF 250-500 J/KG/. VERTICAL SHEAR MAY SUPPORT SOME SUPERCELL OR SMALL BOWING STRUCTURES NEAR THE SRN NEW ENGLAND COAST TODAY WITHIN THE PRIMARY RAIN BAND...BUT WEAK INSTABILITY WILL TEND TO LIMIT THE SEVERE THREAT WITH THIS ACTIVITY. OTHERWISE...ADDITIONAL CONVECTION MAY FORM WITHIN THE MID LEVEL COLD POOL THIS AFTERNOON...WHERE SOME SMALL HAIL WILL BE POSSIBLE. ...SRN WI/SW LOWER MI AREA TONIGHT... A LEE TROUGH IS INDUCING SLY LOW-LEVEL FLOW AND LOW-LEVEL MOISTURE RETURN ACROSS THE SRN PLAINS. THIS MOISTURE /DEWPOINTS IN THE 50S TO LOWER 60S/ WILL SPREAD NWD/NNEWD ACROSS THE ERN PLAINS TOWARD THE UPPER MS VALLEY BY TONIGHT. THE MOISTURE RETURN WILL OCCUR BENEATH A WARM ELEVATED MIXED LAYER AND IN A REGIME OF HEIGHT RISES IN THE WAKE OF THE OH VALLEY TROUGH...THUS DEEP CONVECTION IS NOT EXPECTED TODAY. THE THREAT FOR ELEVATED THUNDERSTORMS WILL INCREASE LATE TONIGHT ACROSS SRN WI/SW LOWER MI AS PARCELS GRADUALLY APPROACH SATURATION IN THE 850-700 MB LAYER...WHERE WAA WILL BE MAXIMIZED ON THE NOSE OF A 40 KT LLJ. ELEVATED CAPE AND MID LEVEL LAPSE RATES MAY BECOME SUFFICIENT FOR SOME HAIL NEAR OR AFTER 06Z. ..THOMPSON/CROSBIE.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 16:25:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 12:25:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011625 SWODY1 SPC AC 011623 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1123 AM CDT SUN OCT 01 2006 VALID 011630Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...NORTHEAST STATES... LARGE UPPER TROUGH CONTINUES TO TRACK EASTWARD ACROSS THE NORTHEAST U.S. THIS MORNING...WHILE UPPER RIDGING DEVELOPS ACROSS THE PLAINS STATES. THE PRIMARY BAROCLINIC ZONE ASSOCIATED WITH THE EASTERN TROUGH IS MOVING EASTWARD ACROSS EASTERN NY. STRONG LOW LEVEL WARM ADVECTION AND FORCING ARE PRODUCING WIDESPREAD PRECIPITATION AND CLOUDS THROUGHOUT SOUTHERN/CENTRAL NEW ENGLAND. VERY LIMITED LAPSE RATES AND CAPE VALUES SUGGEST THAT SEVERE THREAT IS LOW...DESPITE IMPRESSIVE LOW LEVEL AND DEEP LAYER VERTICAL SHEAR PROFILES. THERE REMAINS A SMALL AREA FROM RI INTO EASTERN MA WHERE SUFFICIENT LOW LEVEL INSTABILITY COULD RESULT IN LOCALLY DAMAGING WIND GUSTS. HOWEVER...THE THREAT AREA HAS BECOME QUITE SMALL AND SHOULD END BY MID AFTERNOON AS CONVECTIVE LINE MOVES OFFSHORE. IN THE WAKE OF THIS ACTIVITY...CLEARING SKIES WILL ALLOW STRONG HEATING FROM THE NYC AREA WESTWARD INTO PARTS OF EASTERN PA/NJ INTO THE DELMARVA. LOW LEVEL COLD/DRY ADVECTION SHOULD MINIMIZE DEEP CONVECTIVE THREAT. HOWEVER...SOME MODEL GUIDANCE MAINTAINS A RISK OF LOW-TOPPED AFTERNOON SHOWERS/THUNDERSTORMS ACROSS THIS REGION. IF STORMS CAN FORM...COLD THERMODYNAMIC PROFILES WOULD BE FAVORABLE FOR HAIL. THEREFORE...WILL MAINTAIN LOW PROBABILITIES. ...WI/IL... UPPER RIDGING IS OCCURRING ACROSS THE MIDWEST TODAY...ATOP RATHER DRY/STABLE CONDITIONS. STRONG LOW LEVEL WARM/MOIST ADVECTION WILL OCCUR THROUGH TONIGHT RESULTING IN MARGINAL ELEVATED INSTABILITY BY THIS EVENING. MODEL FORECAST SOUNDINGS SUGGEST THAT UNSTABLE LEVEL WILL BE ROOTED ABOVE 700MB...AND WILL YIELD CAPE VALUES BELOW 500 J/KG. GIVEN THIS SCENARIO...IT APPEARS LIKELY THAT OVERNIGHT CONVECTION THAT MAY DEVELOP IN THIS REGION WILL PROBABLY BE NON-SEVERE. ..HART/GRAMS.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 19:52:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 15:52:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011951 SWODY1 SPC AC 011950 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0250 PM CDT SUN OCT 01 2006 VALID 012000Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...LOWER HUDSON VALLEY INTO SRN NEW ENGLAND... AFTERNOON WATER VAPOR IMAGERY SHOWS NEGATIVELY-TILTED SHORT WAVE TROUGH LIFTING NEWD THROUGH THE HUDSON VALLEY WITH AN ASSOCIATED BAND OF STRONG DEEP-LAYER FORCING FOR ASCENT PRECEDING THIS FEATURE OVER WRN INTO CNTRL PARTS OF NEW ENGLAND. IN THE LOW-LEVELS...MESOANALYSIS INDICATED LOW PRESSURE OVER CT WITH ATTENDANT WEAK WARM FRONT EXTENDING EWD THROUGH CAPE COD...WHILE PRIMARY FRONTAL ZONE STRETCHED NW-SE FROM THE ADIRONDACKS THROUGH THIS LOW PRESSURE TO OFF LONG ISLAND. CONSIDERABLE CLOUDS AND PRECIPITATION ARE LIMITING AIR MASS DESTABILIZATION AHEAD OF THIS LOW PRESSURE CENTER AND ALONG AND N OF WARM FRONT ACROSS MUCH OF NEW ENGLAND...HOWEVER BREAKS IN THE CLOUDS HAVE ALLOWED FOR STRONG DIABATIC HEATING AND RESULTANT DESTABILIZATION /SBCAPES OF 500 J/KG/ NEAR AND IN THE WAKE OF FRONTAL ZONE OVER THE LOWER HUDSON VALLEY. VERTICAL SHEAR IS NOT PARTICULARLY STRONG OWING TO CLOSE PROXIMITY OF MID-LEVEL TROUGH AXIS...THOUGH THE PRESENCE OF STEEP LAPSE RATES AND COOL TEMPERATURES PROFILES MAY SUPPORT SOME MARGINALLY SEVERE HAIL/WIND WITH THE STRONGEST STORMS. FARTHER E ACROSS SRN NEW ENGLAND...A LOW SEVERE THREAT WILL BE DEPENDANT ON DEGREE OF DESTABILIZATION THAT CAN OCCUR AHEAD OF SURFACE LOW AND ALONG WARM FRONT THE REMAINDER OF THIS AFTERNOON INTO EVENING. ...UPPER MIDWEST... POTENTIAL FOR ELEVATED TSTMS WILL EXIST TONIGHT WITH ZONE OF STRONG THERMAL/MOIST ADVECTION DEVELOPING ALONG NOSE OF 35-45 KT LLJ. HOWEVER...THE PRESENCE OF WARM LOWER TROPOSPHERIC TEMPERATURES SUGGEST THAT CONSIDERABLE ISENTROPIC ASCENT WILL BE NECESSARY TO FORCE PARCELS TO THEIR LFC...EFFECTIVELY DECREASING POTENTIAL ELEVATED INSTABILITY. STILL...SOME SMALL HAIL WILL BE POSSIBLE WITH THE STRONGEST CELLS. ..MEAD.. 10/01/2006  From swody1 at goshenarc.org Mon Oct 2 00:36:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 20:36:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020035 SWODY1 SPC AC 020034 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 PM CDT SUN OCT 01 2006 VALID 020100Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... MAIN UPPER TROUGH OVER THE NERN U.S. WILL CONTINUE MOVING EWD THROUGH THE PERIOD...WHILE FLATTER/LESS-AMPLIFIED UPSTREAM FLOW PATTERN WILL PREVAIL THROUGH THE END OF THE PERIOD. BROAD ZONE OF WARM ADVECTION EXISTS ACROSS THE N CENTRAL CONUS ATTM...WITH 35-40 KT SWLY LOW-LEVEL JET INDICATED FROM N CENTRAL OK NEWD INTO WI. ISOLATED/ELEVATED STORMS HAVE DEVELOPED ACROSS SRN WI/NRN IL IN RESPONSE...AND AN INCREASE IN CONVECTIVE COVERAGE IS FORECAST OVER THE NEXT SEVERAL HOURS ACROSS THIS REGION AND SEWD INTO LOWER MI/INDIANA. EVENING RAOBS ACROSS THIS REGION CONFIRM ONLY MODEST ELEVATED CAPE...AND MARGINAL CLOUD-LAYER SHEAR. THEREFORE...THOUGH SMALL HAIL MAY OCCUR WITH A FEW STRONGER STORMS...MOST IF NOT ALL HAIL SHOULD REMAIN SUB-SEVERE. ELSEWHERE...A COUPLE OF LIGHTNING STRIKES MAY LINGER BEYOND 02/01Z OVER SRN NEW ENGLAND...CENTRAL AND NRN MS...AND THE TX BIG BEND AREA...BUT EXPECT CONVECTION/LIGHTNING THREAT TO TAPER OFF THROUGH MID-EVENING IN THESE AREAS. ..GOSS.. 10/02/2006  From swody1 at goshenarc.org Mon Oct 2 05:57:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 02 Oct 2006 01:57:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020535 SWODY1 SPC AC 020533 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1233 AM CDT MON OCT 02 2006 VALID 021200Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MS VALLEY/UPPER GREAT LAKES REGION... ...SYNOPSIS... A SERIES OF WEAK MID-LEVEL SHORT-WAVE TROUGHS ARE FORECAST TO MOVE EWD ACROSS THE NRN PLAINS INTO THE UPPER MS VALLEY/UPPER GREAT LAKES ...THROUGH LARGE-SCALE MEAN RIDGE. THIS FLAT RIDGE WILL PREVAIL ACROSS THE MAJORITY OF THE CONUS THROUGH THE PERIOD...AS ERN TROUGH MOVES INTO THE N ATLANTIC AND WRN TROUGH REMAINS OVER THE ERN PACIFIC/WRN CONUS. AT THE SURFACE...A COLD FRONT IS FORECAST TO MOVE SLOWLY SWD/SEWD ACROSS THE N CENTRAL CONUS WHILE BECOMING ORIENTED INCREASINGLY E-W WITH TIME...AS EWD-SURGE OF FRONT IS FORECAST FURTHER N ACROSS ONTARIO. MEANWHILE...A WEAK LOW IS FORECAST TO MOVE ENEWD ALONG THIS FRONT INTO THE MID MO VALLEY REGION DURING THE LATTER HALF OF THE PERIOD. ...UPPER MS VALLEY/UPPER GREAT LAKES REGION... THUNDERSTORMS WILL LIKELY BE ONGOING AT THE START OF THE PERIOD ACROSS PARTS OF THE UPPER GREAT LAKES REGION...IN ZONE OF WARM ADVECTION NEAR THE NOSE OF A VEERING LOW-LEVEL JET. AS THIS CONVECTION SHIFTS EWD/SEWD WITH TIME INTO LOWER MI/IN...DESTABILIZATION SHOULD OCCUR OVER THE UPPER MS VALLEY AS LOW-LEVEL MOISTURE ADVECTS NWD INTO THIS REGION AHEAD OF COLD FRONT...AND BENEATH ELEVATED MIXED LAYER. PRESUMING SOME HEATING CAN OCCUR IN THE WAKE OF INITIAL CONVECTION...MODERATE AIRMASS DESTABILIZATION SHOULD OCCUR -- THOUGH BOUNDARY LAYER WILL LIKELY REMAIN CAPPED WELL INTO THE AFTERNOON. AS COLD FRONT MOVES SEWD INTO THIS REGION DURING THE AFTERNOON/EVENING...SCATTERED CONVECTIVE DEVELOPMENT IS FORECAST. STORMS ARE EXPECTED TO CONTINUE/SPREAD EWD INTO THE OVERNIGHT HOURS...AS SURFACE LOW SHIFTS EWD TOWARD THE REGION IN CONJUNCTION WITH AN UPPER IMPULSE MOVING EWD ACROSS THE PLAINS DURING THE LATTER HALF OF THE PERIOD. DEEP-LAYER SHEAR IS FORECAST TO REMAIN GENERALLY MARGINAL FOR WELL-ORGANIZED STORMS...WITH FASTER WLY FLOW ALOFT REMAINING N OF THE U.S./CANADA BORDER. HOWEVER...GIVEN DEGREE OF INSTABILITY WHICH WILL LIKELY EVOLVE...A FEW STRONGER MULTICELL CLUSTERS AND PERHAPS A COUPLE SUPERCELL STORMS WILL BE POSSIBLE. MAIN SEVERE THREAT SHOULD BE HAIL...THOUGH LOCALLY-DAMAGING WINDS WILL ALSO BE POSSIBLE -- MAINLY DURING THE AFTERNOON AND EARLY EVENING. ..GOSS.. 10/02/2006  From swody1 at goshenarc.org Mon Oct 2 12:43:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 02 Oct 2006 08:43:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 021242 SWODY1 SPC AC 021241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT MON OCT 02 2006 VALID 021300Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY INTO TONIGHT FROM NE IA TO SW LOWER MI... ...NE IA TO SW LOWER MI AREA THROUGH TONIGHT... SRN STREAM OF THE WLYS...FROM SRN CA NEWD TO THE CENTRAL HIGH PLAINS AND THEN EWD TO THE MS VALLEY...WILL HELP MAINTAIN A LEE CYCLONE INVOF N/NE NEB THROUGH THE PERIOD. A BAROCLINIC ZONE EXTENDS NEWD FROM THE LEE CYCLONE...AND THIS BOUNDARY WILL MOVE SEWD ACROSS WI/MI IN THE WAKE OF A NRN STREAM WAVE CROSSING NW ONTARIO BY LATE TONIGHT. PERSISTENT SLY/SWLY LOW-LEVEL FLOW ACROSS THE ERN PLAINS WILL MAINTAIN AN INFLUX OF MOISTURE /BOUNDARY LAYER DEWPOINTS IN THE 60S/ ACROSS THE CORN BELT...BENEATH STEEP MID LEVEL LAPSE RATES. ONGOING ELEVATED CONVECTION OVER LAKE MI/SW LOWER MI MAY PERSIST THROUGH THE FIRST HALF OF THE DAY OVER LOWER MI AND NRN INDIANA IN CONJUNCTION WITH THE LLJ AND CONTINUED WAA ATOP THE COLD POOL GENERATED BY THE CONVECTION. ADDITIONAL THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE BY LATE AFTERNOON/EVENING ACROSS NE IA/CENTRAL AND SRN WI/NRN IL AS LOW-LEVEL MOISTENING AND NEAR RECORD MAXIMUM TEMPERATURES /85-90 F/ GRADUALLY WEAKEN CONVECTIVE INHIBITION...AND A WEAK MID LEVEL WAVE MOVES EWD FROM NE NEB THIS MORNING TO IA/NRN IL BY THIS EVENING. POTENTIALLY STRONG INSTABILITY /8 C/KM LAPSE RATES AND MLCAPE OF 2000-3000 J/KG/ WILL SUPPORT INTENSE UPDRAFTS CAPABLE OF PRODUCING AT LEAST ISOLATED LARGE HAIL...ALONG WITH THE THREAT FOR ISOLATED DAMAGING DOWNBURST WINDS. DEEP LAYER VERTICAL SHEAR...HOWEVER...IS EXPECTED TO BE RATHER MODEST /0-6 KM BULK SHEAR OF 20-30 KT/...AND CONVECTIVE MODE SHOULD CONSIST PRIMARILY OF MULTICELL CLUSTERS THROUGH LATE TONIGHT AS CONVECTION OVERSPREADS NRN INDIANA/SRN LOWER MI. ..THOMPSON/CROSBIE.. 10/02/2006  From swody1 at goshenarc.org Wed Oct 4 01:01:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 03 Oct 2006 21:01:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040101 SWODY1 SPC AC 040059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT TUE OCT 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MO VALLEY EWD ACROSS SRN PORTIONS OF THE UPPER GREAT LAKES... ...MID MO VALLEY AND SRN MN EWD ACROSS LOWER MI... STRONG/LOCALLY-SEVERE STORMS ARE MOVING EWD ACROSS CENTRAL AND NRN WI ATTM...N OF SURFACE WARM FRONT WHICH NOW EXTENDS FROM A LOW NEAR SIOUX CITY IA ENEWD ACROSS SRN MN...AND THEN SEWD ACROSS CENTRAL WI INTO THE CHICAGO AREA. THOUGH STORMS REMAIN ELEVATED...MODERATE INSTABILITY IS INDICATED ABOVE THE SURFACE STABLE LAYER -- PER EVENING MINNEAPOLIS AND GREEN BAY SOUNDINGS -- WHICH IS SUPPORTING VIGOROUS STORMS. OVERNIGHT...EXPECT STORM COVERAGE TO INCREASE N OF WARM FRONT AND SPREAD EWD ACROSS LK MI INTO LOWER MI...AS INTENSIFYING SWLY LOW-LEVEL JET VEERS WITH TIME. MEANWHILE...DEVELOPMENT WITHIN WARM SECTOR ACROSS IA REMAINS MORE UNCERTAIN. EVENING SOUNDINGS REVEAL A RELATIVELY DRY LOWER TROPOSPHERE...AND A CAPPED BOUNDARY LAYER. THOUGH APPROACH OF SEVERAL UPPER FEATURES FROM THE W MAY AID IN ISOLATED STORM DEVELOPMENT NEAR SURFACE LOW AND SWWD ALONG SLOWLY ADVANCING COLD FRONT...THE MAJORITY OF THE CONVECTION SHOULD REMAIN ALONG AND N OF WARM FRONT ACROSS WI AND LOWER MI. ALONG WITH SUBSTANTIAL INSTABILITY...EVENING RAOBS REVEAL SHEAR FAVORABLE FOR SUPERCELLS ACROSS MN AND INTO WI...WITH 40 TO 60 KT WLY FLOW AT MID-LEVELS. THIS SUGGESTS THAT LARGE HAIL REMAINS LIKELY WITH ONGOING ELEVATED CONVECTION. GREATEST THREAT FOR DAMAGING WINDS SHOULD REMAIN ACROSS SRN WI AND PERHAPS INTO NERN IA/NRN IL...WHERE SURFACE-BASED OR NEAR SURFACE-BASED CONVECTION WOULD BE POSSIBLE. A FEW TORNADOES ALSO REMAIN POSSIBLE ACROSS THIS REGION...AS SELY BOUNDARY LAYER FLOW INVOF WARM FRONT IS RESULTING IN FAVORABLE LOW-LEVEL SHEAR. DAMAGING WIND/TORNADO THREAT SHOULD SPREAD EWD ACROSS LK MI INTO LOWER MI LATER THIS EVENING. ..GOSS.. 10/04/2006  From swody1 at goshenarc.org Wed Oct 4 04:50:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 04 Oct 2006 00:50:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040450 SWODY1 SPC AC 040448 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1148 PM CDT TUE OCT 03 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NY/PA WSWWD ACROSS THE OH VALLEY... ...SYNOPSIS... MID-LEVEL SHORT-WAVE TROUGH WILL MOVE ACROSS THE OH VALLEY/GREAT LAKES REGION THIS PERIOD...ON NRN PERIPHERY OF S CENTRAL U.S. UPPER RIDGE. AS THE TROUGH REACHES THE ERN CONUS...THE OVERALL UPPER FLOW FIELD WILL AMPLIFY...AS RIDGE EXPANDS NWD ACROSS THE CENTRAL CONUS UPSTREAM OF ERN TROUGH AND DOWNSTREAM OF LARGE UPPER LOW/TROUGH OVER THE W COAST. AT THE SURFACE...A N-S BAROCLINIC ZONE IS FORECAST TO REMAIN ROUGHLY STATIONARY ACROSS THE GREAT BASIN AND SRN CA AHEAD OF UPPER LOW. MEANWHILE...THE COLD FRONT ASSOCIATED WITH THE ERN U.S. SHORT-WAVE TROUGH IS INITIALLY FORECAST TO EXTEND FROM LOWER MI WSWWD INTO OK AND THE SRN TX PANHANDLE. BY LATE AFTERNOON/EARLY EVENING...THE FRONT IS FORECAST TO EXTEND FROM NEW ENGLAND WSWWD ALONG THE OH RIVER AND THEN INTO CENTRAL OK...AND THEN WILL CONTINUE SHIFTING SEWD THROUGH THE END OF THE PERIOD. ...NY/PA WSWWD ACROSS THE OH VALLEY... CONVECTION WILL BE ONGOING INVOF FRONT AT THE START OF THE PERIOD...AND WILL CONTINUE/SHIFT SEWD WITH TIME IN CONJUNCTION WITH THE FRONT. THIS WILL HINDER THE POTENTIAL FOR SIGNIFICANT HEATING/DESTABILIZATION ACROSS PARTS OF THE REGION -- PARTICULARLY ACROSS OH/PA/NY -- DURING THE DAY. NONETHELESS...WITH 35 TO 45 KT MID-LEVEL FLOW SPREADING SEWD ACROSS THE MID AND UPPER OH VALLEY...EXPECT LOCALLY-DAMAGING WINDS AND SOME HAIL WITH STORMS ORGANIZED LINEARLY ALONG/AHEAD OF FRONT. SOMEWHAT GREATER DESTABILIZATION WILL BE POSSIBLE FROM SWRN OH SWWD ALONG FRONT...BUT WITH DEEP-LAYER WIND FIELD EXPECTED TO BE WEAKER WITH SWWD EXTENT ALONG THE FRONT...THREAT FOR HAIL/DAMAGING WINDS SHOULD STILL REMAIN RELATIVELY LOW. THEREFORE...WILL MAINTAIN 15% SEVERE PROBABILITY ALONG THE FRONT ACROSS THIS REGION...WITH THREAT LIKELY DIMINISHING DURING THE EVENING AS BOUNDARY LAYER STABILIZES AND FRONT SHIFTS SEWD AWAY FROM THE STRONGER FLOW ALOFT. ...ID AND VICINITY... MARGINAL INSTABILITY IS FORECAST ACROSS PARTS OF THE GREAT BASIN AND NWRN CONUS...THOUGH ONGOING STORMS AT THE BEGINNING OF THE PERIOD SHOULD LIMIT OVERALL DEGREE OF DESTABILIZATION. GREATEST INSTABILITY IS FORECAST BY THE MODELS ACROSS ERN OREGON AND INTO ID...BENEATH DIFFLUENT UPPER FLOW ON NERN PERIPHERY OF UPPER LOW. EXPECT STORMS TO REDEVELOP/INCREASE DURING THE AFTERNOON...WITH A FEW STRONGER/ORGANIZED UPDRAFTS POSSIBLE GIVEN ENHANCED /AROUND 40 KT/ SLY MID-LEVEL FLOW ACROSS THIS REGION. THOUGH MARGINAL INSTABILITY WILL TEMPER OVERALL SEVERE THREAT...MARGINAL HAIL OR A LOCALLY STRONGER GUST OR TWO MAY OCCUR WITH MORE INTENSE CONVECTIVE CELLS THROUGH EARLY EVENING. ..GOSS/TAYLOR.. 10/04/2006  From swody1 at goshenarc.org Thu Oct 5 05:38:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 01:38:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050538 SWODY1 SPC AC 050536 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1236 AM CDT THU OCT 05 2006 VALID 051200Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... SIGNIFICANT AMPLIFICATION OF LARGE SCALE MID/UPPER LEVEL FLOW WILL OCCUR ACROSS THE CONUS THIS PERIOD AS CURRENT SPLIT-FLOW REGIME UNDERGOES A TRANSITION TO MORE OF AN OMEGA-BLOCK CONFIGURATION CENTERED ON THE CNTRL U.S. BY FRIDAY MORNING. DEEP CLOSED LOW OFF THE WEST COAST WILL EDGE SLOWLY INLAND AND EWD TOWARD THE GREAT BASIN TODAY WHILE DOWNSTREAM SUB-TROPICAL RIDGE MAINTAINS ITS DOMINANCE ACROSS THE SOUTH...AND EXPANDS OVER THE CNTRL AND NRN PLAINS. A LEAD SHORT WAVE TROUGH AND ASSOCIATED FRONT WILL MOVE OFF THE NEW ENGLAND COAST TODAY AS THE NEXT UPSTREAM TROUGH DEVELOPS SEWD AND AMPLIFIES ACROSS THE GREAT LAKES THROUGH TONIGHT. STRONGEST HEIGHT FALLS WITH THIS TROUGH WILL MOVE TOWARD THE MID ATLANTIC REGION THROUGH EARLY FRIDAY...EVENTUALLY INDUCING SECONDARY CYCLOGENESIS ALONG THE COLD FRONT TRAILING FROM LEAD SYSTEM. ...CNTRL APPALACHIANS ACROSS VA/NC... LOW LEVEL WIND SHIFT/BACK DOOR FRONT ASSOCIATED WITH UPPER TROUGH CROSSING NEW ENGLAND IS EXPECTED TO SETTLE SWD/SWWD ACROSS ERN AND SRN VA/NRN NC THROUGH THE AFTERNOON. NEUTRAL LARGE SCALE UPPER FORCING FOR ASCENT WILL EXIST ACROSS THE REGION BETWEEN DEPARTING SHORT WAVE TROUGH AND AMPLIFYING UPSTREAM SYSTEM OVER THE GREAT LAKES. NONETHELESS...OROGRAPHIC LIFT AND MESOSCALE FORCING NEAR THE BOUNDARY...ALONG WITH WEAK TO LOCALLY MODEST DIURNAL DESTABILIZATION...SHOULD PROVE SUFFICIENT FOR TSTM DEVELOPMENT OVER PARTS OF VA/NC...AND ERN KY/TN...THROUGH AFTERNOON. WITH INSTABILITY AND SHEAR ACROSS THE AREA EXPECTED TO REMAIN GENERALLY WEAK DURING THIS TIME FRAME...SEVERE HAIL/WIND POTENTIAL SHOULD BE LIMITED. LARGE SCALE FORCING FOR ASCENT AND DEEP LAYER SHEAR SHOULD INCREASE STEADILY ACROSS THE MID ATLANTIC REGION THROUGH LATE EVENING AS THE MID/UPPER LEVEL TROUGH DIGS SEWD FROM THE GREAT LAKES. IT IS POSSIBLE THAT STORM ORGANIZATION AND COVERAGE COULD INCREASE DURING THIS TIME IF INSTABILITY CAN PERSIST INTO THE EVENING HOURS. GIVEN UNCERTAINTY IN AVAILABLE INSTABILITY AFTER DARK...HIGHER SEVERE WEATHER PROBABILITIES WILL NOT BE ISSUED AT THIS TIME. ...SOUTHWEST TO GREAT BASIN... AN EXTENSIVE SWATH OF STRONG DEEP LAYER MERIDIONAL FLOW WILL PERSIST AHEAD OF THE PACIFIC COAST TROUGH AND CONTRIBUTE TO CONTINUED NWD TRANSPORT OF EAST PACIFIC MOISTURE ACROSS THE SRN PLATEAU AND GREAT BASIN REGIONS. CLOUD COVER...PRECIPITATION...AND MEAGER LOW LEVEL MOISTURE ARE EXPECTED TO LIMIT MORE WIDESPREAD STRONG DESTABILIZATION. HOWEVER...POCKETS OF STRONGER INSOLATION... OROGRAPHIC FORCING...AND IMPULSES ROTATING THROUGH THE LARGE SCALE TROUGH...WILL ALL SUPPORT EPISODIC DEVELOPMENT OF BANDS/LINES OF DEEP CONVECTION SPREADING OVER A LARGE REGION. THIS ACTIVITY WILL EXIST WITHIN STRONG UNIDIRECTIONAL SHEAR AND IT IS POSSIBLE THAT LINE SEGMENTS AND CELLS COULD BECOME BETTER ORGANIZED AND PERSISTENT AS LOCALLY STRONGER INSTABILITY IS ENCOUNTERED AND/OR STRONGER FORCING IS REALIZED DURING THE FORECAST PERIOD. WHILE SMALL SCALE LEWPS AND BOWS WITH ENHANCED DOWNBURST WIND AND HAIL THREAT APPEAR POSSIBLE...AN ACCURATE DEPICTION OF AN AREA OF GREATER SEVERE WEATHER POTENTIAL IS NOT POSSIBLE AT THIS TIME. PARTS OF THE REGION MAY BE UPGRADED IN LATER OUTLOOKS AS MESOSCALE DETAILS BECOME BETTER DEFINED. ..CARBIN.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 12:43:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 08:43:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051242 SWODY1 SPC AC 051241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT THU OCT 05 2006 VALID 051300Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... A MORE AMPLIFIED PATTERN WILL EVOLVE OVER THE CONUS THROUGH TOMORROW AS A MID LEVEL RIDGE BUILDS OVER THE PLAINS DOWNSTREAM FROM THE CLOSED LOW OVER CA...AND A SEPARATE SHORTWAVE TROUGH OVER WRN ONTARIO/LAKE SUPERIOR DIGS SEWD TO THE UPPER OH VALLEY/CENTRAL APPALACHIANS. THE PRIMARY THUNDERSTORM THREAT AREAS WILL BE ACROSS A BROAD SWATH OF THE GREAT BASIN IN ADVANCE OF THE CA LOW...AND INVOF THE SRN APPALACHIANS IN ADVANCE OF THE DIGGING TROUGH. ...GREAT BASIN THROUGH TONIGHT... A BROAD PLUME OF MID LEVEL MOISTURE FROM THE ERN PACIFIC WILL PERSIST OVER AZ/UT AND ADJACENT STATES WITHIN THE WARM CONVEYOR BELT E OF THE SLOW MOVING LOW NEAR THE CENTRAL CA COAST. A BELT OF 45-65 KT SLY/SSWLY MID LEVEL FLOW WILL COINCIDE WITH THE MOISTURE PLUME...RESULTING IN SUFFICIENT DEEP LAYER VERTICAL SHEAR FOR ORGANIZED/PERSISTENT THUNDERSTORMS THROUGH THE PERIOD FROM WRN AZ NWD OVER UT/NV TO SRN ID. HOWEVER...WIDESPREAD CLOUDS AND POOR MID LEVEL LAPSE RATES WITHIN THE MOISTURE PLUME WILL TEND TO LIMIT THE DEGREE OF INSTABILITY. POCKETS OF SURFACE HEATING WITHIN CLOUD BREAKS MAY ALLOW SUFFICIENT DESTABILIZATION FOR SUPERCELLS AND/OR SHORT BOWING SEGMENTS WITH LARGE HAIL AND DAMAGING GUSTS. HOWEVER...ANY SUCH FAVORED AREAS OF SURFACE HEATING...AS WELL AS EMBEDDED SPEED MAXIMA TO HELP FOCUS THUNDERSTORM DEVELOPMENT...ARE DIFFICULT TO DISCERN AT THIS TIME. THEREFORE...A LARGE AREA OF 5% HAIL/WIND PROBABILITIES WILL BE MAINTAINED...ALONG WITH THE POSSIBILITY OF AN UPGRADE TO PORTIONS OF THIS AREA DURING THE DAY IF THE THREAT BECOMES MORE FOCUSED/APPARENT. ...NRN CA/S CENTRAL ORE TODAY... SCATTERED THUNDERSTORMS WILL LIKELY CONTINUE THROUGH THE DAY FROM N/NE CA INTO SRN ORE IN THE REGION OF PRONOUNCED ASCENT N/NE OF THE CLOSED LOW ALONG THE CENTRAL CA COAST. THOUGH VERTICAL SHEAR WILL BE RELATIVELY WEAK...COOL MID LEVEL TEMPERATURES AND STEEP LAPSE RATES MAY SUPPORT MARGINALLY SEVERE HAIL IN THE STRONGER STORMS. ...ERN TN/KY INTO NC/VA THIS AFTERNOON/EARLY TONIGHT... A SURFACE COLD FRONT WILL CONTINUE SLOWLY SEWD ACROSS TN/KY TO THE SRN APPALACHIANS LATE TODAY...AND SWD ACROSS VA INTO NC. THE FRONT WILL BE ACCOMPANIED BY A WEAK MID LEVEL TROUGH TODAY OVER THE SRN APPALACHIANS...WHILE WEAK CYCLOGENESIS IS EXPECTED OVER THE CAROLINAS ALONG THE FRONT AND IN ADVANCE OF A STRONGER/LARGER SCALE WAVE DIGGING TOWARD THE CENTRAL APPALACHIANS BY LATE TONIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TODAY INTO TONIGHT ALONG THE FRONT. AFTERNOON MLCAPE VALUES OF 1000-1500 J/KG ACROSS ERN TN/SE KY MAY SUPPORT A FEW STRONG STORMS...BUT THE OVERALL SEVERE THREAT WILL BE LIMITED BY BOTH RELATIVELY WEAK MID LEVEL LAPSE RATES AND VERTICAL SHEAR IN THE WARM SECTOR FROM ERN TN/KY INTO THE CAROLINAS THIS AFTERNOON. SOMEWHAT STRONGER VERTICAL SHEAR IS EXPECTED ALONG AND IMMEDIATELY N OF THE E-W FRONT ACROSS SRN VA/NRN NC THIS AFTERNOON INTO EARLY TONIGHT...BUT WEAK INSTABILITY WILL KEEP ANY SEVERE STORM THREAT QUITE MARGINAL IN THIS AREA. ..THOMPSON/TAYLOR.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 16:32:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 12:32:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051631 SWODY1 SPC AC 051630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT THU OCT 05 2006 VALID 051630Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SOUTHEAST ID AND NORTHWEST UT... ...UT/ID... MORNING SATELLITE LOOPS SHOW A DEEP UPPER LOW OFF THE CENTRAL CA COAST...WITH SEVERAL FEATURES EMBEDDED IN FAST SOUTHWESTERLY FLOW FROM CA ACROSS NV/UT INTO ID. WIDESPREAD AND AMPLE MID LEVEL MOISTURE IN MOIST CONVEYOR BELT FROM SOUTHERN NV ACROSS UT WILL LIKELY RESULTING IN CLOUDS AND LESSENED DAYTIME HEATING. HOWEVER...STEEP LOW LEVEL LAPSE RATES MAY DEVELOP ALONG WEST EDGE OF CLOUDS FROM NORTHWEST UT INTO SOUTHEAST ID. FORECAST SOUNDINGS IN THIS AREA SHOW MLCAPE VALUES OVER 500 J/KG...PROMOTING THE DEVELOPMENT OF SCATTERED AFTERNOON AND EVENING THUNDERSTORMS. ALTHOUGH MID LEVEL TEMPERATURES ARE SLIGHTLY WARMER AND TIMING OF UPPER FEATURES DO NOT APPEAR AS FAVORABLE AS YESTERDAY...COVERAGE OF STORMS MAY BE GREATER DUE TO AMPLE MID LEVEL MOISTURE. VERTICAL SHEAR VALUES AND POTENTIAL FOR DESTABILIZATION SUGGEST A RISK OF DAMAGING WINDS AND HAIL IN STRONGER STORMS. ...CENTRAL APPALACHIANS... SOUTHERN FRINGE OF STRONGER WESTERLIES EXTENDS FROM KY/TN INTO VA/NC. SCATTERED AFTERNOON THUNDERSTORMS ARE LIKELY TO INCREASE AHEAD OF WEAKENING SURFACE FRONT SWEEPING THROUGH THE REGION. SURFACE DEWPOINTS IN THE 60S AND STRONG HEATING WILL RESULT IN MLCAPE VALUES OF 800-1200 J/KG. HOWEVER...WEAKER WIND FIELDS AND LAPSE RATES THAN PAST FEW DAYS SUGGEST THAT OVERALL SEVERE THREAT IS RATHER MARGINAL. NEVERTHELESS...STRONGEST CELLS COULD PRODUCE LOCALLY GUSTY WINDS AND HAIL. ..HART/JEWELL.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 19:43:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 15:43:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051943 SWODY1 SPC AC 051941 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0241 PM CDT THU OCT 05 2006 VALID 052000Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTN ACROSS PARTS OF THE GREAT BASIN/NRN INTERMOUNTAIN REGION.... ...INTERMOUNTAIN WEST... THE MOST SIGNIFICANT SHORT WAVE IMPULSE ASSOCIATED WITH THE WESTERN U.S. UPPER TROUGH STILL APPEARS TO BE DIGGING AROUND THE SOUTHWESTERN PERIPHERY OF A CLOSED LOW NEAR THE CENTRAL CALIFORNIA COAST. HOWEVER...DEEP LAYER SOUTHERLY FLOW AHEAD OF LARGE SCALE TROUGH AXIS CONTINUES TO TRANSPORT MOISTURE NORTHWARD FROM THE LOWER LATITUDE EASTERN PACIFIC...TOWARD THE SOUTHERN PLATEAU/GREAT BASIN. INCREASING MOISTURE/OROGRAPHY AND FURTHER SURFACE HEATING IS EXPECTED TO CONTRIBUTE TO SUBSTANTIAL CONVECTIVE DEVELOPMENT LATE THIS AFTERNOON FROM PARTS OF ARIZONA INTO SOUTHERN/EASTERN PORTIONS OF THE GREAT BASIN. ENHANCED BY FAVORABLE DEEP LAYER SHEAR BENEATH 40-50 KT SOUTHWESTERLY MID-LEVEL FLOW..A LOCALIZED SEVERE THREAT WILL EXIST IN STRONGER CELLS...WITH RELATIVELY WEAK DESTABILIZATION THE PRIMARY LIMITING FACTOR TO CONVECTIVE POTENTIAL. IT APPEARS THAT THE BEST POTENTIAL FOR SEVERE STORMS MAY BE FROM PARTS OF NORTHEAST NEVADA/EXTREME NORTHWEST UTAH INTO SOUTHWESTERN IDAHO...WHERE LOW-LEVEL MOISTURE TRANSPORT IS FOCUSED BENEATH NORTHEASTERN FRINGE OF MID-LEVEL DRY SLOT. THOUGH MID-LEVEL FORCING FOR UPWARD VERTICAL MOTION IS UNCERTAIN...DIFLUENCE ALOFT MAY ENHANCE STORM DEVELOPMENT. AND...WITH MIXED LAYER CAPE POSSIBLY AS HIGH AS 500-1000 J/KG...HODOGRAPHS ARE SUFFICIENT FOR ISOLATED SUPERCELLS THROUGH EARLY EVENING. ...TENNESSEE VALLEY INTO MID ATLANTIC STATES... MOIST AIR MASS ALONG STALLED FRONTAL ZONE HAS HEATED AND BECOME WEAK TO LOCALLY MODERATELY UNSTABLE...SUPPORTIVE OF CONVECTIVE DEVELOPMENT. FAVORABLE OROGRAPHY ALONG THE SOUTHERN/CENTRAL APPALACHIANS IS SUPPORTING ADDITIONAL ACTIVITY...WHICH LIKELY WILL INCREASE FURTHER LATE THIS AFTERNOON. WELL TO THE SOUTHEAST OF A SHORT WAVE TROUGH DIGGING ACROSS THE GREAT LAKES REGION...FLOW FIELDS/SHEAR ARE WEAK...BUT UNSATURATED THERMODYNAMIC PROFILES COULD CONTRIBUTE TO ISOLATED DOWNBURSTS IN STRONGER STORMS THROUGH EARLY EVENING. SCATTERED STORMS MAY PERSIST ALONG FRONT AS IT PRESSES SOUTHEAST OF THE CENTRAL/SOUTHERN APPALACHIANS LATER TONIGHT...WITH CONTINUED SOUTHEASTWARD PROGRESSION OF UPSTREAM TROUGH. ..KERR.. 10/05/2006  From swody1 at goshenarc.org Fri Oct 6 00:59:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 20:59:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060058 SWODY1 SPC AC 060057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT THU OCT 05 2006 VALID 060100Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SOUTHWEST TO GREAT BASIN... SATELLITE IMAGERY DEPICTS EXTENSIVE BAROCLINIC LEAF LAYERED CLOUD PATTERN FROM THE BAJA NNEWD ACROSS AZ...UT...WRN CO...AND ID/WY. THIS ZONE OF STRONG ASCENT EXISTS TO THE EAST OF A SLOW MOVING LARGE SCALE UPPER LOW DROPPING SLOWLY SSEWD OVER THE CNTRL CA COAST. EXTENSIVE MOISTURE PLUME AND DYNAMIC LIFT AHEAD OF THE TROUGH WILL CONTINUE TO RESULT IN SUFFICIENT INSTABILITY TO MAINTAIN WIDESPREAD CONVECTION TONIGHT FROM PARTS OF AZ NWD ACROSS THE GREAT BASIN AND WRN SLOPES OF THE ROCKIES. WITH MUCAPE VALUES STRUGGLING TO CLIMB MUCH ABOVE ABOUT 500 J/KG...UPDRAFTS WILL REMAIN RELATIVELY WEAK AND INCREASINGLY DECOUPLED FROM SURFACE LAYER. DESPITE THESE LIMITATIONS...EXTENSIVE NATURE OF CONVECTION AND VERY STRONG SHEAR SUGGEST THE POSSIBILITY OF ONE OR TWO WIND OR HAIL EVENTS AS SMALLER SCALE IMPULSES PIVOT AROUND THE LARGE SCALE TROUGH AND ENHANCE FORCED ASCENT IN MOIST WEAKLY UNSTABLE REGIME. ...CNTRL APPALACHIANS... SCATTERED DISORGANIZED STORMS PERSIST ACROSS THE CUMBERLAND PLATEAU LATE THIS EVENING AS A COLD FRONT MOVES TOWARD THE CNTRL APPALACHIANS. MODEL FORECASTS SUGGEST THAT CONVECTION SHOULD PERSIST IN WEAKLY UNSTABLE AIR MASS FROM THE APPALACHIANS EWD ACROSS VA/NC TONIGHT AS UPWARD VERTICAL MOTION INTENSIFIES WITH THE APPROACH OF A STRONG SHORT WAVE TROUGH. AS SHEAR AND FORCING FOR ASCENT STRENGTHEN THROUGH THE NIGHT...A FEW STRONG TO ISOLATED SEVERE STORMS WITH HAIL AND/OR WIND APPEAR POSSIBLE. THUS...THIS FORECAST WILL MAINTAIN A RELATIVELY SMALL LOW PROBABILITY SEVERE AREA FROM ONGOING ACTIVITY OVER ERN TN...EWD ACROSS SWRN VA/NRN NC. ..CARBIN.. 10/06/2006  From swody1 at goshenarc.org Fri Oct 6 05:33:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 06 Oct 2006 01:33:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060532 SWODY1 SPC AC 060531 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1231 AM CDT FRI OCT 06 2006 VALID 061200Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN NV...MUCH OF AZ AND UT... ...SYNOPSIS... LARGE SCALE OMEGA BLOCK PATTERN WILL CONTINUE ACROSS THE LOWER 48 STATES THIS PERIOD WITH STRONG TROUGHS ALONG EACH COAST...AND A LARGE SCALE RIDGE DOMINATING THE CNTRL U.S. FROM TX TO THE GREAT LAKES. A SIGNIFICANT SHORT WAVE IMPULSE ACCOMPANIED BY 70KT MID LEVEL FLOW WILL EJECT FROM THE BASE OF THE DEEP WEST COAST TROUGH AND MOVE FROM THE LOWER CO RIVER VALLEY...NEWD ACROSS THE GREAT BASIN...AND THEN OVER THE NRN ROCKIES THROUGH EARLY SATURDAY. DOWNSTREAM FROM THE CNTRL STATES UPPER RIDGE...A VIGOROUS SHORT WAVE TROUGH...CURRENTLY CROSSING THE OH VALLEY...WILL DIG SSEWD ACROSS THE CAROLINAS WHILE EVOLVING INTO A COMPACT COLD CORE VORTEX OVER NC THROUGH LATE TODAY. ...SOUTHWEST/GREAT BASIN... STRONG DEEP LAYER SLY FLOW CONTINUES TO TRANSPORT ABUNDANT MOISTURE NWD AHEAD OF THE STRONG SLOW MOVING UPPER LOW OVER CA. LOW LEVELS HAVE ALSO MOISTENED THROUGH A COMBINATION OF ADVECTION AND DIABATIC EFFECTS. WHILE FORCING FOR ASCENT IS EXPECTED TO INCREASES FURTHER TODAY WITH THE NEWD ACCELERATION OF SHORT WAVE IMPULSE OUT OF SRN CA...OVERALL DESTABILIZATION WILL PROBABLY REMAIN MARGINAL GIVEN POTENTIAL FOR WIDESPREAD CLOUDINESS AND PRECIPITATION. HOWEVER...RELATIVELY STEEP LAPSE RATES MAINTAINED BY ADIABATIC COOLING/STRONG ASCENT SHOULD CONTRIBUTE TO CAPE ON THE ORDER OF 200-500 J/KG WHICH WILL ADEQUATELY FUEL RELATIVELY LOW-TOPPED CONVECTION. GIVEN THE PRESENCE OF VERY STRONG EFFECTIVE SHEAR...AND FOCUSED FORCING ON THE NOSE OF 70 KT MID LEVEL JET STREAK SPREADING ACROSS SRN NV/WRN AZ THROUGH THE AFTERNOON... EXPECT AN INCREASE IN SEVERE STORM POTENTIAL. FAST-MOVING LINES/BANDS OF STORMS AND A FEW SUPERCELLS APPEAR POSSIBLE AS THE STRONG ASCENT ACCOMPANYING THE MID LEVEL IMPULSE ACTS ON MOIST/UNSTABLE AIR MASS. IN ADDITION TO HAIL AND HIGH WINDS...AN ISOLATED TORNADO CANNOT BE RULED OUT. ORGANIZED ACTIVITY AND SEVERE THREAT SHOULD SPREAD NEWD FROM ERN NV/AZ AND INTO UT THROUGH LATE AFTERNOON/EVENING. ...MID ATLANTIC/SOUTHEAST COASTS... SURFACE FRONT SHOULD STRENGTHEN AND SURGE SEWD INTO WARM/MOIST AIR MASS ALONG THE COASTAL PLAIN AS VIGOROUS MID LEVEL CYCLOGENESIS COMMENCES OVER SRN VA/NC THIS AFTERNOON. WHILE STRONGER DEEP SHEAR IS FORECAST TO LAG THE FRONTAL LIFT...INCREASINGLY STRONG FORCING ACROSS THE REGION COULD AID TSTM DEVELOPMENT ALONG THE FRONT AS IT MOVES EAST. A COUPLE OF SEVERE STORMS WITH STRONG TO DAMAGING WINDS APPEAR POSSIBLE OVER A RELATIVELY SMALL REGION. ISOLATED AND MARGINALLY SEVERE HAIL MAY ALSO OCCUR BENEATH THE DEVELOPING MID LEVEL LOW CENTER OVER ERN NC THROUGH EVENING. ...NRN ROCKIES TO NRN PLAINS... CONVECTION IS FORECAST TO INCREASE IN A SW-NE BAND FROM NRN NV ACROSS ID...AND INTO PARTS OF MT...FROM LATE AFTERNOON INTO THE NIGHT AS STRENGTHENING MID LEVEL DEFORMATION ZONE ACTS ON NWRN PERIPHERY OF DEEP MOISTURE PLUME. INSTABILITY AND SHEAR ARE EXPECTED TO REMAIN MARGINAL WITHIN THIS AXIS...BUT LAPSE RATES AND FORCING APPEAR SUFFICIENT FOR A COUPLE OF HAIL STORMS OVER THE NRN ROCKIES. LOW-AMPLITUDE SHORT WAVE IMPULSE AND INCREASING LOW LEVEL SLY FLOW MAY COMBINE TO PRODUCE A FEW ELEVATED STORMS ACROSS THE WRN DAKOTAS THROUGH EARLY SATURDAY. A LOW PROBABILITY OF HAIL WILL EXIST WITH THIS ACTIVITY. ..CARBIN/EVANS.. 10/06/2006  From swody1 at goshenarc.org Sat Oct 7 00:49:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 06 Oct 2006 20:49:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070052 SWODY1 SPC AC 070051 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT FRI OCT 06 2006 VALID 070100Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN NV/SRN UT... ...SRN GREAT BASIN... SATELLITE IMAGERY AND SHORT-TERM MODEL DATA DEPICTED AN INTENSE MID LEVEL VORTICITY MAX ASSOCIATED WITH AN 80KT JET STREAK CURRENTLY EJECTING NEWD FROM THE BASE OF A DEEP TROUGH ACROSS CA AND THE LOWER CO RIVER VALLEY. STRONG LIFT ACCOMPANYING THIS IMPULSE WAS ACTING ON A MOIST AND WEAKLY UNSTABLE AIR MASS FROM SERN NV ACROSS SRN UT THIS EVENING. RESULTING FAST-MOVING BANDS AND CLUSTERS OF SCATTERED LOW-TOPPED STORMS SHOULD CONTINUE TO SPREAD NEWD AND EWD FROM ERN NV TO SRN UT THROUGH TONIGHT. WHILE MEAGER INSTABILITY WILL TEMPER A MORE WIDESPREAD SEVERE THREAT WITH THIS CONVECTION...MAGNITUDE OF FORCING AND SHEAR WILL REMAIN SUFFICIENT FOR POSSIBLE HAIL/WIND EVENTS FROM SOME OF THE STRONGER/MORE PERSISTENT UPDRAFTS. ...SOUTHEAST... TIGHTLY WOUND MID LEVEL CYCLONE CONTINUES TO EVOLVE NEAR THE VA/NC BORDER AREA TONIGHT. BULK OF DEEP CONVECTION ASSOCIATED WITH THIS SYSTEM HAS MOVED OFFSHORE WITH THE STRONG FRONTAL SURGE ARCING FROM THE NC/VA CAPES TO THE GA COAST. VERY STRONG FORCING AND LOW STATIC STABILITY MAY CONTINUE TO CONTRIBUTE TO A MAUL LAYER ACROSS INLAND PORTIONS OF NERN NC AND SERN VA WHERE ISOLATED STRONG UPDRAFTS COULD STILL PRODUCE SMALL HAIL TONIGHT. FARTHER SOUTH...FRONTAL LIFT CONTINUES TO SPAWN A FEW INTENSE STORMS OFF THE SC COAST...WWD/INLAND TO WEST OF SAV. RECENT TRENDS IN RADAR REFLECTIVITY SUGGEST AREAL EXTENT OF SEVERE POTENTIAL WITH THIS ACTIVITY SHOULD CONTINUE TO DIMINISH. ..CARBIN.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 12:17:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 08:17:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071220 SWODY1 SPC AC 071218 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0718 AM CDT SAT OCT 07 2006 VALID 071300Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... THE HIGH AMPLITUDE MID/UPPER LEVEL FLOW PATTERN PERSISTS ACROSS THE CONUS WITH LARGE RIDGE CENTRAL U.S FLANKED NEAR BOTH COASTS BY TROUGHS. IN THE WRN U.S. CURRENTLY A STRONG IMPULSE EJECTING FROM WRN TROUGH AND WILL PHASE WITH NRN STREAM SUPPORTING A DEEPENING SURFACE LOW SERN MT MOVING QUICKLY INTO WESTERN ONTARIO TONIGHT. WESTERN TROUGH THEN REFORMS AN UPPER LOW THAT DROPS SWD INTO SRN CA TONIGHT. THE STILL INTENSIFYING UPPER LOW NEAR THE NC/VA BORDER PROGGED TO CONTINUE SSWWD INTO SERN GA TONIGHT. CURRENT ASSOCIATED SURFACE LOW NEAR COASTAL BORDER VA/NC WILL GRADUALLY FILL AS COLD FRONT PUSHES FURTHER OFFSHORE. ...SWRN U.S... DRIER SWLY FLOW HAS SPREAD ACROSS MUCH OF AZ IN THE WAKE OF S/WV THAT EJECTED FRIDAY ACROSS INTERMOUNTAIN REGION. MOIST SUBTROPICAL PLUME PERSISTS ACROSS NWRN MEXICO EXTREME ERN AZ AND NM. AS UPPER LOW REDEVELOPS SRN CA...PREVAILING FLOW WILL GRADUALLY BACK TO MORE SLY BY TONIGHT WITH MOISTURE AGAIN INCREASING BACK INTO AZ. SHEAR PROFILES HAVE WEAKENED WITHIN THE MOIST PLUME TODAY AND WITH ONLY LIMITED HEATING...INSTABILITY SHOULD GENERALLY REMAIN LESS THAN 1000 J/KG. SCTD THUNDERSTORMS SHOULD DEVELOP BY AFTERNOON NEAR HIGHER TERRAIN WITH POTENTIAL FOR ISOLATED MARGINAL WIND/HAIL EVENTS. THUNDERSTORMS WILL LIKELY CONTINUE AFTER DARK AND POSSIBLY SPREAD FURTHER W INTO AZ AS BACKING FLOW TONIGHT BRINGS MOISTURE INTO CENTRAL AZ. ...MID ATLANTIC COAST... STRONG LOW LEVEL ONSHORE FLOW SERN VA SHOULD SLOWLY WEAKEN AS UPPER LOW CONTINUES TO DRIFT SSWWD AND COOLER MORE STABLE AIR MASS MOVES TO THE COAST. ISOLATED SEVERE WILL STILL BE POSSIBLE THIS AM GIVEN THE STRONG SHEAR AND MARGINAL INSTABILITY. THESE CONDITIONS SHOULD WORK SWD ALONG NRN NC COAST DURING THE DAY AND GRADUALLY DIMINISH. ..HALES/GRAMS.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 16:27:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 12:27:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071630 SWODY1 SPC AC 071629 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1129 AM CDT SAT OCT 07 2006 VALID 071630Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... DEEP NC UPR LOW EXPECTED TO CONTINUE SSW TROUGH SUNDAY AS HIGH AMPLITUDE RIDGE PERSISTS OVER THE MS VLY AND MAIN PORTION OF WRN STATES TROUGH LIFTS NE INTO S CNTRL CANADA. AT LWR LEVELS...SURFACE TROUGH ASSOCIATED WITH NC LOW SHOULD REDEVELOP S ACROSS FAR ERN NC/SC THROUGH THE PERIOD...WHILE LOW ASSOCIATED WITH WRN TROUGH LIFTS RAPIDLY NE ACROSS ND INTO WRN ONTARIO. ...TIDEWATER VA S INTO FAR ERN NC/OUTER BANKS... UNUSUAL PATTERN WITH SSW-MOVING NOR'EASTER. SURFACE AND SATELLITE DATA SHOW AREA OF MODIFIED TROPICAL AIR MASS /EFFECTIVE WARM SECTOR/ EXTENDING FROM OFF THE SE VA/NC CST WWD IN A NARROWING WEDGE INTO EXTREME SE VA NEAR ORF. SSW MOTION OF UPR SYSTEM AND ASSOCIATED BAND OF DEEP ELY FLOW TO ITS NORTH SUGGEST THAT THE WARM SECTOR WILL REDEVELOP SSW WITH TIME AS SHALLOW BOUNDARY THAT MOVED JUST OFF THE NC CST LATE YESTERDAY RETROGRESSES W. WHILE LITTLE SURFACE DEVELOPMENT IS EXPECTED THROUGH THE PERIOD... ONSHORE MOVEMENT OF NARROW WARM SECTOR AND ASSOCIATED LOW LEVEL CONVERGENCE/ENHANCED WIND SHEAR FIELDS MAY BE SUFFICIENT TO SUPPORT A BAND OR TWO OF THUNDERSTORMS WITH LOW LEVEL ROTATION. IF THE GUIDANCE IS TO BE BELIEVED REGARDING FCST SSW WOBBLING OF UPR COLD POCKET...WARM SECTOR INSTABILITY SHOULD GRADUALLY DIMINISH THROUGH THE PERIOD AFTER SOME TEMPORARY DESTABILIZATION FROM SURFACE HEATING OVER EXTREME ERN NC TODAY. IF INSTABILITY/CONVERGENCE DO NEVERTHELESS PROVE SUFFICIENT TO SUPPORT SUSTAINED SURFACE-BASED STORMS IN WARM SECTOR...A LOW PROBABILITY THREAT WILL EXIST FOR BRIEF TORNADOES. THIS THREAT SHOULD MOVE SWD FROM TIDEWATER VA/FAR NE NC EARLY THIS AFTN TO THE HATTERAS AREA LATER TODAY/TONIGHT...TO POSSIBLY THE MHX/ILM AREA EARLY SUNDAY. ...SW U.S... DRIER SW FLOW HAS OVERSPREAD MUCH OF AZ IN THE WAKE OF SHORTWAVE TROUGH NOW LIFTING NE ACROSS WY/MT. SUBTROPICAL MOISTURE PLUME WILL...HOWEVER...PERSIST FROM NE SONORA INTO EXTREME ERN AZ AND NM. AS UPR TROUGH LINGERS IN THE WEST AND A LOW REDEVELOPS ALONG THE SRN CA CST...DEEP FLOW WILL SLOWLY BACK TO A MORE SLY COMPONENT...ALLOWING MOISTURE TO ONCE AGAIN INCREASE ACROSS CNTRL AZ THIS EVENING. SHEAR PROFILES HAVE WEAKENED WITHIN THE MOIST PLUME RELATIVE TO YESTERDAY...BUT HEATING SHOULD BOOST SBCAPE TO AROUND 1000 J/KG. SCTD THUNDERSTORMS SHOULD STRENGTHEN/DEVELOP BY AFTN INVOF HIGHER TERRAIN IN ERN AZ/NM AND FAR SW AZ...WITH POTENTIAL FOR ISOLATED MARGINALLY SEVERE WIND/HAIL. SOME OF THIS ACTIVITY COULD CONTINUE INTO TONIGHT AND MAY SPREAD FARTHER W INTO AZ AS UPR FLOW BACKS. ...CNTRL PLNS... SURFACE HEATING AND CONVERGENCE/WARM ADVECTION ALONG ENHANCED LEE TROUGH TRAILING SW FROM ND LOW MAY YIELD A FEW STORMS WITH GUSTY WINDS IN PARTS OF NEB/NE CO AND SE SD LATER TODAY INTO TONIGHT. ..CORFIDI/BOTHWELL.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 19:48:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 15:48:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071951 SWODY1 SPC AC 071949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SAT OCT 07 2006 VALID 072000Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...TIDEWATER VA S INTO FAR ERN NC/OUTER BANKS... CLOSED UPPER LOW WILL CONTINUE TO MOVE SSWWD INTO SC THIS FORECAST PERIOD...REACHING SRN SC/GA COAST REGION BY 12Z SUNDAY. STRONGER MID LEVEL FLOW IS EXPECTED TO REMAIN ALONG THE WRN/SRN PERIPHERIES OF THIS SYSTEM. IN THE LOW LEVELS...SMALL WARM SECTOR WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S EXTENDED INLAND FROM FAR SERN VA S TO EAST CENTRAL NC. AS THE CLOSED LOW MOVES TO THE SSW...ATTENDANT MOIST/WARM SECTOR SHOULD ALSO REDEVELOP TO THE SSW ALONG AND JUST INLAND OF THE NC COAST. OBJECTIVE ANALYSES INDICATED STRONGER INSTABILITY WAS LOCATED OFFSHORE...WHILE WEAK MID LEVEL LAPSE RATES AND LARGE SCALE SUBSIDENCE IN WAKE OF UPPER LOW WERE TENDING TO LIMIT DEVELOPMENT OF DEEP MOIST CONVECTION WITHIN INLAND WARM SECTOR. NARROW AXIS OF CONVECTION SHOULD CONTINUE INTO THE EVENING ALONG WARM CONVEYOR BELT EXTENDING INTO NERN NC/SERN VA. POTENTIAL FOR A BRIEF TORNADO WILL PERSIST FOR THE NEXT FEW HOURS...PRIOR TO LOSS OF DAYTIME HEATING...AS GREATER SURFACE VORTICITY AND LOW LCLS EXIST ALONG THIS NARROW CONVERGENCE BAND. THIS THREAT MAY DEVELOP SWD ALONG NC COAST TONIGHT AS ASSOCIATED CONVERGENCE BAND MOVES S. ...SERN AZ/WRN-SRN NM... NARROW AXIS OF SURFACE DEWPOINTS IN THE MID-UPPER 50S LOCATED OVER SERN AZ/SWRN NM COMBINED WITH ADDITIONAL SURFACE HEATING SUGGESTS THE AIR MASS SHOULD REMAIN MARGINALLY TO MODERATELY UNSTABLE /MLCAPE 500-1000 J/KG/ INTO THE EARLY EVENING. ALTHOUGH MID-UPPER LEVEL FLOW REGIME IS SOMEWHAT FLAT ACROSS THIS REGION...WATER VAPOR IMAGERY INDICATED THAT A WEAK SUB-TROPICAL IMPULSE MAY BE TRAVERSING NRN MEXICO INTO SWRN NM AT THIS TIME...AIDING IN ONGOING CONVECTION. WEAK DEEP LAYER SHEAR IS EXPECTED TO LIMIT SEVERE THREAT...BUT A FEW OF THE STRONGER STORMS MAY BECOME CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL AND/OR WIND GUSTS. ...CNTRL PLNS... SURFACE HEATING AND CONVERGENCE/WARM ADVECTION ALONG ENHANCED LEE TROUGH TRAILING SW FROM ND LOW MAY YIELD A FEW STORMS WITH GUSTY WINDS IN PARTS OF NEB/NE CO AND SE SD LATER TODAY INTO TONIGHT. ..PETERS.. 10/07/2006  From swody1 at goshenarc.org Sun Oct 8 00:28:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 20:28:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080030 SWODY1 SPC AC 080029 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 PM CDT SAT OCT 07 2006 VALID 080100Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SOUTHWEST... WEAK PERTURBATIONS EMBEDDED WITHIN DEEP LAYER SWLY FLOW AND MOISTURE PLUME AHEAD OF STRONG SRN CA TROUGH CONTINUE TO AID DEEP CONVECTION FROM WRN MEXICO TO NM/CO AND THE EXTREME WRN TX PNHDL THIS EVENING. MUCH OF THIS ACTIVITY EXISTS TO THE EAST OF A BAND OF STRONGER FLOW ALOFT AND GENERALLY DISORGANIZED NATURE OF THE CONVECTION AND LIMITED CAPE SHOULD PRECLUDE SEVERE POTENTIAL OVERNIGHT. ...SOUTHEAST... DEEP MID LEVEL LOW CONTINUES TO DROP SOUTH ACROSS THE CAROLINAS TONIGHT WHILE PRIMARY SURFACE LOW WITH THIS SYSTEM REMAINS OFF THE OUTER BANKS. MOIST ONSHORE FLOW ACROSS ERN NC BENEATH MID LEVEL DRY SLOT DID ALLOW FOR WEAK DESTABILIZATION AND A FEW STORMS PERSIST IN THIS REGION WITHIN MODEST WARM CONVEYOR BELT. WITH THE MID/UPPER LOW MOVING AWAY FROM THE REGION AND BEGINNING TO FILL...AND DIURNAL STABILIZATION SETTING IN...THE CHANCE FOR A SEVERE STORM APPEARS TO BE DECREASING. OVER FL...WIND SHIFT/FRONT ASSOCIATED WITH THE ANOMALOUS SYSTEM OVER THE CAROLINAS HAS INTERSECTED EAST COAST SEA-BREEZE BOUNDARY AND RESULTED IN ROBUST TSTM DEVELOPMENT IN WARM MOIST AIR MASS. SUPERCELL MOVING ACROSS ORANGE COUNTY HAS RECENTLY PRODUCED MARGINALLY SEVERE HAIL. ANOTHER HAIL OR WIND REPORT REMAINS POSSIBLE WITH THIS ACTIVITY OVER THE NEXT HALF-HOUR OR SO BUT OVERALL TREND SHOULD BE ONE OF WEAKENING WITH THE LOSS OF DAYTIME HEATING AND LACK OF MORE PRONOUNCED FORCING. ...NRN AND CNTRL PLAINS... HIGH-BASED CONVECTION HAS RECENTLY DEVELOPED ALONG PRE-FRONTAL TROUGH SITUATED ACROSS NCNTRL NEB. ADDITIONAL MESOSCALE FORCING WILL MOVE ACROSS THE REGION TONIGHT AS STRONG COLD FRONT SWEEPS SEWD FROM THE NRN HIGH PLAINS. WELL MIXED AND DRY BOUNDARY LAYER AIR MASS COULD SUPPORT GUSTY DOWNDRAFTS WITH AN ISOLATED STORM OR TWO OVER THE NEXT HOUR BUT LIMITED MOISTURE AND DECOUPLING SHOULD TEMPER MORE WIDESPREAD CONVECTIVE POTENTIAL OVERNIGHT. ..CARBIN.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 04:33:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 00:33:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080436 SWODY1 SPC AC 080434 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1134 PM CDT SAT OCT 07 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SERN AZ AND WRN NM... ...SYNOPSIS... MORE OF A SPLIT FLOW REGIME WILL DEVELOP ACROSS NRN/CNTRL U.S THIS PERIOD AS NRN STREAM REMAINS QUITE PROGRESSIVE...AND SRN STREAM RETAINS SOME AMPLITUDE. STRONGEST HEIGHT FALLS WITH THE NRN STREAM SHORT WAVE TROUGH NOW CROSSING NRN PLAINS WILL SPREAD EAST ACROSS SRN CANADA. HOWEVER...WEAK HEIGHT FALLS ASSOCIATED WITH THIS FEATURE WILL ACT TO DAMPEN THE UPPER RIDGE AXIS FROM THE GREAT LAKES TO THE NORTHEAST. A BROAD BELT OF DEEP LAYER SWLY FLOW WILL PERSIST IN THE WAKE OF THE NRN STREAM IMPULSE...FROM THE SOUTHWEST TO THE UPPER MS VALLEY/GREAT LAKES. AS STRONGER FORCING PULLS AWAY FROM THE PLAINS... ASSOCIATED TRAILING COLD FRONT WILL BE ALIGNED WITH THE DEEP LAYER SWLY FLOW. THEREFORE THE FRONT WILL MAKE ONLY GRADUAL EWD/SEWD PROGRESS ACROSS THE UPPER MS AND MO VALLEYS THIS PERIOD... AND SHOULD EXTEND FROM LOWER MI TO KS BY EARLY MONDAY. HIGH PLAINS SEGMENT OF THE COLD FRONT IS FORECAST TO SURGE SWD FROM ERN CO AND ACROSS THE TX PNHDL TODAY AND TONIGHT WITH LIFT ACROSS THIS BOUNDARY LIKELY BEING ENHANCED BY A LOW AMPLITUDE IMPULSE EMANATING OUT OF THE SRN STREAM. UPPER LOW ACROSS SRN CA WILL BEGIN TO BE SHUNTED EWD ACROSS THE LOWER CO RIVER VALLEY THROUGH THIS PERIOD AS A NRN STREAM DISTURBANCE SPREADS SEWD ACROSS THE INTERIOR NORTHWEST. OTHER SRN STREAM CLOSED LOW...OVER THE SOUTHEAST...WILL CONTINUE TO FILL AND DRIFT ACROSS THE GA/NRN FL COASTLINE LATER THIS AFTERNOON. ...AZ/NM... DYNAMIC FORCING FOR ASCENT ASSOCIATED WITH THE SRN CA UPPER LOW WILL SPREAD EAST ATOP A RELATIVELY MOIST AND INCREASINGLY UNSTABLE AIR MASS ACROSS PARTS OF SERN AZ THIS AFTERNOON. MODEL GUIDANCE INDICATES STRONG CONVECTION WILL DEVELOP AS THE LIFT ASSOCIATED WITH THE TROUGH COMBINES WITH DIURNAL HEATING AND UPSLOPE FLOW. DEEP LAYER SHEAR IS ALSO EXPECTED TO STRENGTHEN COINCIDENT WITH TSTM DEVELOPMENT AND SHOULD SUPPORT STORM ORGANIZATION. LINES OR CLUSTERS OF STORMS AND PERHAPS A FEW SUPERCELLS APPEAR POSSIBLE AND COULD BE ACCOMPANIED BY HAIL AND LOCALLY HIGH WINDS FROM SERN AZ EWD/NEWD INTO PORTIONS OF WRN NM. ...SRN HIGH PLAINS... ANOTHER AREA OF DEEP CONVECTION MAY EVOLVE AS A LOW AMPLITUDE MID/UPPER WAVE DEVELOPS NNEWD FROM SRN/CNTRL NM ACROSS SERN CO AND THE TX/OK PNHDLS LATER TODAY. THIS FEATURE IS EMBEDDED WITHIN TROPICAL MOISTURE CONNECTION BUT LIMITED LOW LEVEL MOISTURE AND POTENTIAL FOR ABUNDANT CLOUD COVER ACROSS THE SRN HIGH PLAINS MAY LIMIT GREATER SURFACE-BASED DESTABILIZATION. IF HEATING AND WEAK DESTABILIZATION CAN OCCUR AHEAD OF THE FRONTAL SURGE DEVELOPING ACROSS THESE AREAS LATER TODAY...LIFT AND SHEAR APPEAR ADEQUATE FOR A COUPLE OF SEVERE STORMS. ANY SURFACE-BASED ACTIVITY MAY BE QUICKLY UNDERCUT BY THE COLD FRONT BUT COULD STILL POSE A THREAT OF MARGINALLY SEVERE HAIL. GIVEN UPPER FORCING AND LIFT ACROSS THE ADVANCING FRONT...A SMALL MCS MAY EVOLVE FROM THE INITIAL ACTIVITY AND DEVELOP EAST ACROSS THE TX PNHDL THROUGH SUNDAY NIGHT. MARGINAL HAIL AND GUSTY WINDS MAY ACCOMPANY THIS SYSTEM BUT AREAL EXTENT OF SEVERE POTENTIAL AND LEVEL OF UNCERTAINTY AT THIS TIME DO NOT WARRANT HIGHER SEVERE PROBABILITIES. ...SOUTHEAST COAST/FL... MOIST ONSHORE FLOW ACROSS ERN CAROLINAS BENEATH COLD POOL AND LIFT ASSOCIATED WITH MID/UPPER LEVEL LOW MAY BE ENOUGH FOR A COUPLE OF TSTMS. INSTABILITY...HOWEVER...WILL LIKELY BE WEAK AND LITTLE SEVERE THREAT IS CURRENTLY ANTICIPATED. FURTHER SOUTH...OVER FL...GREATER SURFACE-BASED INSTABILITY MAY DEVELOP ACROSS THE ECNTRL PART OF THE PENINSULA. FORCING AND STEEPER LAPSE RATES ASSOCIATED WITH THE UPPER SYSTEM WILL BRUSH THE EAST COAST AS SEA-BREEZE CONVECTIVE DEVELOPMENT OCCURS DURING THE AFTERNOON. PRIOR NAM-WRF FORECASTS WERE VERY ACCURATE IN DEPICTING THE ISOLATED DEVELOPMENT THAT OCCURRED SATURDAY EVENING. LATEST NAM-WRF SUGGESTS A SIMILAR ENVIRONMENT AND SCENARIO APPEAR POSSIBLE SUNDAY AFTERNOON AND EVENING. THUS...LOW SEVERE PROBABILITIES FOR WIND/HAIL...AND AN ISOLATED TORNADO...WILL BE INTRODUCED FOR PARTS OF ERN FL TODAY. ..CARBIN/GRAMS.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 12:33:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 08:33:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081236 SWODY1 SPC AC 081235 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0735 AM CDT SUN OCT 08 2006 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ AND WRN NM... ...SYNOPSIS... MS VLY RIDGE WILL DEAMPLIFY THIS PERIOD AS SHORTWAVE TROUGH THAT CROSSED THE RCKYS YESTERDAY CONTINUES ENE ACROSS THE UPR GRT LKS/SRN ONTARIO...AND AN UPSTREAM IMPULSE NOW OVER VANCOUVER ISLAND AMPLIFIES SE INTO THE PAC NW. PATTERN CHANGE WILL ALLOW CLOSED SYSTEM THAT DEVELOPED OVER SRN CA ON SATURDAY TO LINGER OVER THAT REGION FOR ANOTHER 24 HRS. FARTHER E...WEAKENING OF MS VLY RIDGE WILL ALSO PROMOTE A MODEST INCREASE IN WLY FLOW ACROSS THE SERN U.S...AND SHOULD FORCE ANOMALOUS SYSTEM STILL DRIFTING S/SW ACROSS SC TO TURN MORE E AND OFF THE GA CST EARLY MONDAY. ...ERN CAROLINAS... A SYNOPTIC SETUP SIMILAR TO SATURDAY'S BUT DISPLACED FARTHER SW WILL PREVAIL OVER THE SERN STATES TODAY AS DEEP CLOSED LOW CONTINUES TO WOBBLE SSW ACROSS SC/ERN GA. WRN PART OF SYSTEM WARM SECTOR SHOULD CONTINUE TO REDEVELOP SW ACROSS THE SRN NC AND ERN SC CSTL PLN TODAY BEFORE UPR SYSTEM BEGINS TO TURN MORE ELY OVER GA THIS EVENING. WIDELY SCATTERED TRANSIENT ROTATING STORMS/WEAK SUPERCELLS PERSISTED DURING THE OVERNIGHT INVOF SLOW WWD-MOVING BOUNDARY JUST OFF THE NC CST...AND BANDS OF SLIGHTLY ELEVATED STORMS REGENERATED THROUGH THE NIGHT A BIT FARTHER W INTO THE SRN NC/ERN SC SANDHILLS/PIEDMONT. SURFACE HEATING LIKELY WILL ALTER THIS NOCTURNAL CONVECTIVE PATTERN TODAY...BUT OVERALL SETUP SHOULD REMAIN FAVORABLE FOR ISOLATED TORNADOES AND POSSIBLE WATERPSOUTS WITH ANY LONGER-LIVED/MORE DISCRETE STORMS NEAR THE CST. ...CNTRL/SRN FL PENINSULA... BAND OF ENHANCED /40+ KT/ WLY MID LEVEL FLOW ON SRN FRINGE OF SC/GA LOW WILL OVERSPREAD CNTRL FL TODAY. WEAK CONVERGENCE SHOULD PERSIST INVOF SLOWLY MOVING COLD FRONT NOW EXTENDING FROM NEAR SRQ TO NEAR VRB. RELATIVELY WEAK...MAINLY WLY LOW LEVEL WINDS SHOULD FAVOR CONVERGENCE/DIURNAL STORM DEVELOPMENT ON E CST SEA BREEZE FRONT...ESPECIALLY NEAR INTERSECTION WITH SYNOPTIC COLD FRONT. ACTIVITY MAY BE SLOW TO DEVELOP GIVEN MODEST MID LEVEL LAPSE RATES. BUT ONCE STARTED...HI PWS AND STRENGTHENING FLOW ALOFT SUGGEST POTENTIAL FOR HIGH WIND BEFORE STORMS MOVE OFFSHORE EARLY TONIGHT. ...AZ/WRN NM... HIGHER CLOUDS OF EARLIER SUBTROPICAL PLUME ARE LIFTING NEWD OUT OF AZ ATTM...SUGGESTING THAT FAIRLY STRONG HEATING WILL OCCUR TODAY ALONG WRN EDGE OF LOW LEVEL MOISTURE AXIS. GOES/GPS PW DATA SHOW MOISTURE COVERING ROUGHLY THE SERN THIRD OF THE STATE...AND MOISTURE MAY SPREAD A BIT FARTHER W WITH TIME AS CA UPR LOW EDGES ONLY SLOWLY E TOWARD THE LWR CO VLY ...ALLOWING MORE SUBSTANTIAL MOISTURE TO SPREAD N FROM SONORA. COUPLED WITH STEEP LOW TO MID LEVEL LAPSE RATES AND MODERATE /30 KT/ SSWLY FLOW...SETUP COULD YIELD CLUSTERS/BANDS OF STRONG TO SEVERE STORMS WITH HIGH WIND AND POSSIBLY MARGINALLY SEVERE HAIL. ...SRN HI PLNS... SATELLITE AND MODEL FCSTS SUGGEST THAT A WEAK IMPULSE WILL LIFT NNE ACROSS NM TODAY...WHERE CLOUD COVER WILL BE SUBSTANTIAL. BUT MODERATE BOUNDARY LAYER MOISTURE IS IN PLACE...AND WEAKLY CONVERGENT UPSLOPE FLOW WILL PREVAIL OVER THE ERN NM HI PLNS E/NE INTO W TX AND THE TX PANHANDLE. THIS SETUP MAY SUPPORT DEVELOPMENT OF A FAIRLY EXTENSIVE BAND OF MAINLY DIURNAL STORMS OVER THE SRN HI PLNS. A FEW STRONG TO POSSIBLY SEVERE WIND/HAIL EVENTS MAY OCCUR WITH THIS ACTIVITY THROUGH EARLY TONIGHT. ..CORFIDI/GRAMS.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 16:22:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 12:22:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081625 SWODY1 SPC AC 081624 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT SUN OCT 08 2006 VALID 081630Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS ERN AZ AND WRN NM... ...SYNOPSIS... ANY SEVERE THUNDERSTORM THREAT THIS FORECAST PERIOD WILL BE ASSOCIATED WITH THE UPPER LOWS OVER SRN CA AND SERN GA. BOTH CIRCULATION CENTERS WILL TURN TOWARD THE E TODAY WITH THE GA SYSTEM MOVING OFFSHORE BY 00Z. ...EASTERN AZ/WRN NM... MOISTURE IS SPREADING BACK INTO ERN THIRD OF AZ AS WINDS HAVE BACKED TO THE E OF THE SRN CA UPPER LOW. AVAILABLE MOISTURE STILL IS NOT IMPRESSIVE BASED ON 12Z SOUNDING FROM TUS AND GPS PW READING OVER SRN AZ WITH GENERALLY .75 IN OR LESS. NWD TRANSPORT OF MOISTURE FROM NWRN MEX WILL CONTINUE THRU THE DAY ON THE INCREASING SLY FLOW AHEAD OF UPPER LOW. COMBINED WITH STRONG INSOLATION AND STEEPENING LAPSE RATES COUPLED WITH 35-40KT OF DEEP LAYER SHEAR...THUNDERSTORMS EXPECTED TO DEVELOP BY MID AFTERNOON E OF A LINE FROM MOGOLLON RIM SWD TO W OF NOG. WITH POTENTIAL FOR MLCAPES AOA 1000 J/KG AND 8C/KM MID LEVEL LAPSE RATES THERE IS AT LEAST A THREAT OF ISOLATED SEVERE STORMS BY LATE AFTERNOON CONTINUING THRU THE EVENING AS UPPER LOW APPROACHES FROM SERN CA. ...SC COAST... COMPACT UPPER LOW SERN GA WILL BE MOVING EWD OFFSHORE TONIGHT. THRU THIS AFTERNOON SELYS WILL CONTINUE A MOIST ONSHORE FLOW INTO SC COASTAL AREAS. AIR MASS OFFSHORE OVER GULF STREAM IS MOST UNSTABLE AND WITH FAVORABLE CYCLONIC SHEAR STRONG/ISOLATED SEVERE THUNDERSTORMS WILL CONTINUE TO MOVE TOWARD THE SC COAST UNTIL LATER THIS AFTERNOON. PRIMARY SEVERE THREAT WOULD BE ISOLATED WIND DAMAGE AND POSSIBLY A BRIEF TORNADO/WATER SPOUT WITH ANY SUPERCELL THAT MAY FORM OVER WATER AND MOVE ONSHORE. ..HALES/BOTHWELL.. 10/08/2006  From swody1 at goshenarc.org Tue Oct 10 05:54:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 01:54:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100557 SWODY1 SPC AC 100556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT TUE OCT 10 2006 VALID 101200Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF CNTRL INTO ERN TX INTO WRN LA... ...SYNOPSIS... OPENING MID-LEVEL TROUGH ALONG THE AZ/NM BORDER IS FORECAST TO DE-AMPLIFY THROUGH THE PERIOD AS IT RAPIDLY TRANSLATES NEWD INTO THE MID MS VALLEY. AS THIS OCCURS...A STRONG SUBTROPICAL JET WILL BECOME ESTABLISHED FROM THE SWRN DESERTS TO THE LOWER MS VALLEY. IN THE LOW-LEVELS...SURFACE LOW ATTENDANT TO WEAKENING UPPER SYSTEM WILL DEVELOP NEWD FROM SWRN OR W-CNTRL TX INTO SRN MO BY LATE TONIGHT WITH TRAILING COLD FRONT PUSHING EWD THROUGH CNTRL/ERN TX. ...CNTRL/ERN TX INTO WRN LA... A COMPLEX FORECAST EXISTS OWING TO THE LIKELIHOOD OF AN ONGOING MCS OVER CNTRL TX AT THE ONSET OF THE FORECAST PERIOD...AND ITS EFFECTS ON AIR MASS DESTABILIZATION AND EVENTUAL FRONTAL MOVEMENT. 10/00Z SOUNDINGS FROM THE TX COAST INDICATE THAT A MOIST LOW-LEVEL AIR MASS HAS MOVED ONSHORE WITH LOWEST MEAN MIXING RATIOS OF AROUND 16 G/KG. CURRENT SURFACE OBSERVATIONS AND GOES GPS DATA SHOW THIS MOISTURE ADVECTING NWD INTO CNTRL TX ALONG ERN EDGE OF LLJ BECOMING ESTABLISHED OVER WRN TX. AS MENTIONED ABOVE...STORM CLUSTERS OR AN MCS WILL LIKELY BE ONGOING 10/12Z OVER THE EDWARDS PLATEAU REGION...DRIVEN LARGELY BY LOW-LEVEL WAA REGIME AHEAD OF WEAKENING MID-LEVEL TROUGH. CONSIDERABLE CLOUDS AND PRECIPITATION SHOULD LIMIT LAPSE RATES TO NEAR MOIST ADIABATIC WITH INCREASING BOUNDARY-LAYER MOISTURE LARGELY CONTRIBUTING TO AIR MASS DESTABILIZATION WITH MLCAPES OF 500-1000 J/KG EXPECTED. AS SUCH...SOME DIURNAL WEAKENING OF MCS MAY OCCUR DURING THE MORNING...PRIOR TO STORMS INTENSIFYING BY AFTERNOON OVER CNTRL TX SWD TOWARD THE MIDDLE TX COAST. VERTICAL SHEAR PROFILES WILL BECOME INCREASINGLY SUPPORTIVE OF SUPERCELLS/BOWING STRUCTURES CAPABLE OF MAINLY DAMAGING WINDS AND A FEW TORNADOES OWING TO PERSISTENT LOW-LEVEL WAA PATTERN COUPLED WITH INTENSIFYING SUBTROPICAL JET. ACTIVITY SHOULD MOVE/DEVELOP EWD INTO LA TONIGHT...WITH A CONTINUED THREAT OF ISOLATED DAMAGING WINDS AND PERHAPS A TORNADO OR TWO NEAR AND E OF THE SABINE RIVER VALLEY. FARTHER TO THE N OVER NERN TX INTO SERN OK AND SWRN AR...IT APPEARS THAT INSTABILITY WILL REMAIN QUITE LIMITED SHOULD MCS PERSIST ACROSS CNTRL/ERN TX AS IS BEING FORECAST. SHEAR PROFILES WILL BE SUPPORTIVE OF ORGANIZED...SEVERE STORMS...HOWEVER THE DEGREE OF INSTABILITY REMAINS IN QUESTION ATTM. ..MEAD/GRAMS.. 10/10/2006  From swody1 at goshenarc.org Tue Oct 10 12:48:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 08:48:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101251 SWODY1 SPC AC 101249 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 AM CDT TUE OCT 10 2006 VALID 101300Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF S CNTRL AND SE TX INTO WRN LA... ...SYNOPSIS... AMPLIFICATION OF NRN STREAM TROUGH DROPPING SSE FROM CNTRL CANADA WILL RESULT IN CONTINUED DEAMPLIFICATION OF SRN STREAM IMPULSE OVER NM. THE LATTER SYSTEM SHOULD ACCELERATE ENE ACROSS KS/OK TODAY BEFORE BECOMING ABSORBED INTO NRN TROUGH OVER THE MID MS VLY EARLY WEDNESDAY. AS THIS OCCURS...A STRONG LOW AMPLITUDE SUBTROPICAL JET WILL BECOME ESTABLISHED FROM THE SW U.S. TO THE LWR MS VLY. AT THE SURFACE...PATTERN HAS BEEN COMPLICATED BY ONGOING OVERNIGHT MCSS AND BY EXISTING FRONT THAT HAS BECOME NEARLY STATIONARY FROM THE TX BIG BEND ENE INTO SE OK. WEAK WAVE/INFLECTION AREA ALONG THE BOUNDARY SHOULD WEAKEN OVER S CNTRL TX TODAY AS A NEW WAVE EVENTUALLY FORMS DOWNSTREAM FROM EJECTING UPR VORT OVER THE OZARKS/MID MS VLY. TRAILING COLD FRONT FROM THE WAVE SHOULD ACCELERATE SE ACROSS CNTRL/ERN TX TONIGHT/EARLY WEDNESDAY. ...S CNTRL TX INTO SE TX/WRN LA... SUBSTANTIAL BOUNDARY LAYER MOISTENING HAS OCCURRED IN THE LAST 12-18 HRS ACROSS S CNTRL AND PARTS OF SE TX...WHERE SSELY LOW LEVEL FLOW HAS PREVAILED AND PWS ARE AOA 1.50 INCHES. SEVERAL SMALL MCSS THAT TRACKED ENE ACROSS SW AND S CNTRL TX OVERNIGHT HAVE REINFORCED SW PART OF SYNOPTIC FRONT NOW STALLED ROUGHLY ENE FROM THE TX BIG BEND. FARTHER E...SURFACE DATA AND AXIS OF PERSISTENT SHOWER DEVELOPMENT SUGGEST PRESENCE OF A DEVELOPING WARM FRONT EXTENDING N/S FROM W OF CLL TO NEAR VCT. HIGH CLOUDS WITH SUBTROPICAL JET AND LOW CLOUDS ASSOCIATED WITH UPSLOPE FLOW/WARM ADVECTION WILL SOMEWHAT LIMIT LOW LEVEL DESTABILIZATION IN WARM SECTOR TODAY. BUT GIVEN MOIST BOUNDARY LAYER ENVIRONMENT AND MODERATELY COOL MID LEVEL TEMPERATURES /AROUND MINUS 9 AT 500 MB/...EVEN MODEST HEATING SHOULD BOOST AFTN MLCAPE TO AROUND 1000 J/KG. VERTICAL SHEAR SHOULD REMAIN SUPPORTIVE OF SUPERCELLS/BOWING STRUCTURES CAPABLE OF ISOLATED TORNADOES AND LOCALLY DAMAGING WIND ...BOTH ALONG AFOREMENTIONED BOUNDARIES...AND LATER TODAY WITHIN WARM SECTOR. THE STORMS SHOULD MOVE/DEVELOP E INTO PARTS OF LA TONIGHT...WITH A CONTINUED THREAT FOR MAINLY ISOLATED DAMAGING WINDS AND PERHAPS A TORNADO NEAR AND E OF THE SABINE RVR. FARTHER NE ACROSS NE TX/SE OK AND SW AR...EXPECT THAT LOW LEVEL MOISTURE RETURN WILL BE MINIMAL. COUPLED WITH CLOUD COVER...IT APPEARS THAT INSTABILITY WILL REMAIN LIMITED. THUS...DESPITE PRESENCE OF AMPLE SHEAR FOR ORGANIZED SEVERE STORMS...AS WELL AS SOMEWHAT STRONGER FORCING FOR ASCENT THAN OVER POINTS SOUTH...SEVERE POTENTIAL SHOULD REMAIN LOW. ..CORFIDI.. 10/10/2006  From swody1 at goshenarc.org Tue Oct 10 16:13:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 12:13:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101615 SWODY1 SPC AC 101614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT TUE OCT 10 2006 VALID 101630Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS MUCH AND SOUTHERN AND SOUTHEAST TEXAS... ...SRN TX... UPPER LOW OVER SWRN U.S. MONDAY IS NOW AN OPEN WAVE AND ACCELERATING ENEWD ACROSS SRN HI PLAINS THIS AM. AN UNSEASONABLY STRONG POLAR TROUGH DIGGING INTO CENTRAL U.S. WILL RESULT IN SRN PLAINS SYSTEM TO STEADILY LOSE AMPLITUDE AS IT IS ABSORBED IN THE CONFLUENT FLOW OF THE MUCH STRONGER SYSTEM TO THE N. ONGOING LINEAR MCS NOW TRACKING ACROSS SCENTRAL TX IS BEING FED BY A VERY MOIST AND MODESTLY UNSTABLE SLY FLOW OFF THE WESTERN GULF OF MEXICO. THIS AM SHEAR PROFILES NOTED ON 88-D VADS AND LDB PROFILER SUPPORT SUPERCELL POTENTIAL. ALONG WITH LOW 70S F DEWPOINTS THAT RESULTS IN MLCAPE TO NEAR 1500 J/KG IN WARM SECTOR...WIND DAMAGE AND ISOLATED TORNADOES WILL CONTINUE TO BE A THREAT THRU MUCH OF THE AFTERNOON. SUPERCELLS WILL LIKELY BE EMBEDDED IN THE SQUALL LINE ASSOCIATED WITH THE MCS AS IT CONTINUES TO TRACK TOWARD SERN TX AND UPPER TX COASTAL AREA THIS EVENING. AN ADDITIONAL SEVERE THREAT WILL EXIST ALONG TRAILING CONVECTIVE BOUNDARY INTO SRN TX DURING AFTERNOON WHERE HEATING COULD WEAKEN CAP AND INCREASE INSTABILITY TO AOA 2000 J/KG. WEAKENING SHEAR THIS AREA SHOULD PRECLUDE MORE THAN AN ISOLATED SEVERE THREAT ON THE TRAILING PORTION OF THE OUTFLOW BOUNDARY AS LOW AND MID LEVEL FLOW VEERS AND WEAKENS LATER THIS AFTERNOON IN CONCERT WITH DE AMPLIFYING UPPER WAVE...SEVERE THREAT EXPECTED TO DIMINISH BY THIS EVENING ACROSS SERN TX/SWRN LA. ..HALES/CROSBIE.. 10/10/2006  From swody1 at goshenarc.org Sat Oct 14 05:38:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 01:38:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140540 SWODY1 SPC AC 140538 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1238 AM CDT SAT OCT 14 2006 VALID 141200Z - 151200Z ...NO SVR TSTM AREAS FORECAST... ...SWRN U.S... LATE EVENING MODEL GUIDANCE IS SOMEWHAT CONFLICTING REGARDING THE SPEED/MOVEMENT OF UPPER LOW OFF THE SRN CA COAST INTO AZ LATE IN THE PERIOD. GFS IS SOMEWHAT FASTER AND WEAKER THAN THE NAM AS THIS FEATURE MOVES ACROSS THE SWRN DESERT REGIONS. DESPITE THE MODEL DIFFERENCES...LARGE SCALE ASCENT WILL CERTAINLY INCREASE WITHIN THE WARM CONVEYOR BELT AHEAD OF SFC WIND SHIFT DURING THE DAY ACROSS SERN AZ/SRN NM...ARCING NWWD INTO THE MOUNTAINS OF CNTRL AZ. CONVECTION SHOULD ONCE AGAIN DEVELOP WITHIN THIS STRONG BAROCLINIC ZONE...THOUGH BOUNDARY LAYER MOISTURE/INSTABILITY IS EXPECTED TO REMAIN SOMEWHAT MARGINAL. AT THIS TIME IT APPEARS STRENGTH OF UPDRAFTS WILL PROVE ROBUST WITHIN STRONGLY SHEARED ENVIRONMENT...BUT THERMODYNAMICALLY LACKING FOR ORGANIZED SEVERE THUNDERSTORMS. ANY SEVERE THREAT WILL BE LIMITED TO MAINLY MARGINALLY SEVERE HAIL...AND THIS SHOULD REMAIN SOMEWHAT ISOLATED AND STRONGLY DIURNAL. ...TX COAST... EARLY MORNING SATELLITE IMAGERY SUGGESTS A DEEP TROPICAL CONNECTION FROM LOW LATITUDES EXTENDS FROM CNTRL MEXICO...NEWD INTO THE WRN GULF OF MEXICO. MULTIPLE CLUSTERS OF THUNDERSTORMS EXISTS WITHIN THIS ZONE SOUTH OF THE TX BORDER...EXTENDING WELL SOUTH OF SFC WIND SHIFT. MODELS INSIST A WEAK DISTURBANCE WILL LIFT NEWD WITHIN THIS TROPICAL FEED AND INDUCE WEAK SFC DEVELOPMENT...EITHER IN THE FORM OF A WEAK SFC WAVE...OR PERHAPS A WEAK CLOSED SFC LOW ALONG THE RETREATING BOUNDARY ACROSS THE WRN GULF OF MEXICO NEAR THE LOWER/MIDDLE TX COAST LATE IN THE PERIOD. UNDOUBTEDLY...THIS BAROCLINIC ZONE WILL BE OF CONCERN AS IT FOCUSES DEEP CONVECTION WITHIN INCREASINGLY UNSTABLE/SHEARED LOW LEVEL AIRMASS. AT THIS TIME IT APPEARS GREATEST CONCENTRATION OF INTENSE THUNDERSTORM UPDRAFTS WILL OCCUR JUST OFFSHORE...AT LEAST THROUGH MUCH OF THE PERIOD. WITH TIME THIS BOUNDARY SHOULD MOVE INLAND...BUT IT MAY NOT DO SO UNTIL LATE DAY1 OR PERHAPS DAY2. WILL MAINTAIN LOW PROBABILITIES FOR ISOLATED SEVERE WITH NEAR-SFC BASED SUPERCELL ACTIVITY ALONG THE TX COAST...ESPECIALLY LATE IN THE PERIOD. ..DARROW/GUYER.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 12:35:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 08:35:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141237 SWODY1 SPC AC 141236 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0736 AM CDT SAT OCT 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS PART OF SERN CA/SRN NV INTO NWRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN AND MIDDLE TX COAST LATER TONIGHT... ...SOUTHWEST... EARLY MORNING SURFACE ANALYSES INDICATE LOW CENTER...ASSOCIATED WITH STRONG UPPER LOW NOW MOVING ACROSS SRN CA...IS DEEPENING OVER THE LOWER CO RIVER VALLEY BETWEEN EED AND IGM. ENHANCED LOW LEVEL CONVERGENCE IS INCREASING DEEP ASCENT NEAR THIS FEATURE WHERE SUPERCELLS AND SMALL LINES/BOW ECHOES HAVE PERSISTED OVERNIGHT OVER FAR ERN SAN BERNADINE CO/CA INTO CLARK CO/NV AND SRN MOHAVE CO/AZ. NARROW AXIS OF 55-60 F SURFACE DEW POINTS AND MODEST WARM SECTOR WITH TEMPERATURES AROUND 70F IS SUSTAINING 500 J/KG MLCAPE WITH LITTLE OR NO CINH FROM THE PHX AREA NWWD INTO SERN CA/SRN NV AS OF 12Z. AS 50+ KT SSWLY MID LEVEL JET OVERSPREADS THE REGION...LOW AND DEEP LAYER SHEAR WILL REMAIN ENHANCED TODAY AND LIKELY CONTINUE TO SUPPORT ORGANIZED STORMS INCLUDING SUPERCELLS. THOUGH INSTABILITY WILL REMAIN MEAGER... STRENGTH OF DEEP ASCENT AND SHEAR SHOULD SUPPORT A THREAT OF LARGE HAIL AND DAMAGING WINDS WITH MORE ORGANIZED STORMS AS THEY LIFT NNEWD TODAY. ACTIVITY WILL LIKELY LOSE INTENSITY AS IT SPREADS NWD INTO GREATER STABILITY INTO NERN AZ/CENTRAL NM. ...SRN/CENTRAL TX COASTAL PLAIN... SUBTLE TROPICAL IMPULSE CONTINUES TO SHIFT SLOWLY ACROSS MEXICO THIS MORNING...WHICH IS FORECAST TO AMPLIFY A SURFACE WAVE ALONG QUASI-STATIONARY FRONT NOW EXTENDING FROM DEEP SOUTH TX INTO THE NWRN GULF OF MEXICO DURING LATTER HALF OF THE PERIOD. CLUSTERS OF THUNDERSTORMS WILL LIKELY INCREASE LATER TONIGHT NEAR THIS SURFACE FRONT...AND AHEAD OF WEAK SRN STREAM WAVE...ESPECIALLY AS SSELY H85 WINDS STRENGTHEN AFTER 03Z. GIVEN INFLUX OF MID/UPPER 70F SURFACE DEW POINTS AND FORECAST 0-1 KM SRH IN EXCESS OF 100 M2/S2...LOW LEVEL ROTATION WILL STRENGTHEN WITH OVERNIGHT STORMS ALONG THE LOWER-MIDDLE TX COAST. APPEARS THE POTENTIAL FOR ISOLATED TORNADOES/DAMAGING WINDS WILL LIKEWISE INCREASE AFTER DARK. ..EVANS/GUYER.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 16:34:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 12:34:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141636 SWODY1 SPC AC 141634 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1134 AM CDT SAT OCT 14 2006 VALID 141630Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS CENTRAL AND NRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS LATE TONIGHT ACROSS THE LOWER AND MIDDLE TX COAST... ...AZ TODAY... A COLD CORE LOW OVER SE CA WILL MOVE SLOWLY EWD TO WRN AZ THIS AFTERNOON AND CENTRAL AZ OVERNIGHT. A BELT OF 45-60 KT SLY/SSWLY MID LEVEL FLOW E OF THE LOW WILL SPREAD EWD OVER AZ TODAY...COINCIDENT WITH A PLUME OF LOW-MID LEVEL MOISTURE AND ASCENT. SCATTERED THUNDERSTORMS WILL PERSIST THROUGH THE DAY WITHIN THIS BAND MAINLY ALONG AND N OF THE MOGOLLON RIM...WHERE VERTICAL SHEAR PROFILES WILL BE SUFFICIENT FOR A FEW SUPERCELLS. THE MORE INTENSE STORMS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL...ALONG WITH THE POSSIBILITY OF AN ISOLATED TORNADO. PLEASE REFER TO MCD 2110 /VALID THROUGH 18Z/ FOR ADDITIONAL INFORMATION. ...W TX/SRN NM LATER TODAY INTO EARLY TONIGHT... A BROAD FETCH OF L0W-MID LEVEL MOISTURE IS SPREADING NEWD FROM THE CENTRAL/SRN GULF OF CA AND NW MEXICO INTO SRN NM AND FAR W TX...IN ADVANCE OF THE MID LEVEL LOW OVER THE LOWER CO RIVER VALLEY. FARTHER E...BOUNDARY LAYER DEWPOINTS IN THE LOWER 60S ARE SPREADING NWWD UP THE PECOS VALLEY INTO SW TX/SE NM. REGIONAL 12Z SOUNDINGS SHOWED RATHER MODEST MID LEVEL LAPSE RATES GENERALLY AOB 6 C/KM...WHILE SATELLITE IMAGERY SUGGEST THAT WIDESPREAD CLOUDS WILL PERSIST THROUGH MUCH OF THE DAY AND LIMIT SURFACE HEATING /ESPECIALLY THE PECOS VALLEY/. STILL...BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 50S AND SOME CLOUD BREAKS BY LATE AFTERNOON MAY SUPPORT THE DEVELOPMENT OF ISOLATED STRONGER STORMS ACROSS FAR W TX AND SW NM...AND SCATTERED THUNDERSTORMS SHOULD FORM BY THIS EVENING ACROSS SW TX/SE NM. VERTICAL SHEAR WILL BE FAVORABLE FOR SUPERCELLS OVER THIS ENTIRE AREA...AND THE MORE INTENSE STORMS COULD PRODUCE ISOLATED/MARGINALLY SEVERE HAIL AND WIND DAMAGE THROUGH EARLY TONIGHT. ...S TX LATE TONIGHT... A LARGE CLUSTER OF THUNDERSTORMS PERSISTS OVER THE W CENTRAL AND SW GULF OF MEXICO IN ASSOCIATION WITH A WEAK MID LEVEL WAVE LIFTING NNEWD NEAR TAMPICO. THIS WAVE/CONVECTION WILL INTERACT WITH THE BAROCLINIC ZONE ACROSS THE LOWER TX COAST AND ADJACENT NW GULF...SUPPORTING WEAK CYCLOGENESIS/STRENGTHENING GRADIENTS AND AN ASSOCIATED INCREASE IN LOW-LEVEL SHEAR. FORECAST SOUNDINGS SHOW SOME POTENTIAL FOR ROTATING STORMS WITH STRONG LOW-LEVEL SHEAR IN A VERY MOIST ENVIRONMENT WITH WEAK INSTABILITY...WHICH MAY SUPPORT AN ISOLATED TORNADO OR TWO BEFORE 12Z. ..THOMPSON/TAYLOR.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 19:44:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 15:44:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141945 SWODY1 SPC AC 141943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT SAT OCT 14 2006 VALID 142000Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF CNTRL AZ...NRN AZ AND FAR SRN NV... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER TX COAST... ...CNTRL AND NRN AZ/FAR SRN NV... A WELL-DEVELOPED UPPER-LOW OVER SRN CA WILL DRIFT EWD THIS AFTERNOON INTO AZ WITH A DUAL-CENTERED SFC LOW REMAINING PRESENT ACROSS CNTRL AZ. THUNDERSTORMS ARE DEVELOPING JUST AHEAD OF THE TRACK OF THE UPPER-LOW IN THE LEFT EXIT REGION OF A 70 KT MID-LEVEL JET. THE CONVECTION SHOULD GRADUALLY EXPAND IN COVERAGE EWD WITH INDIVIDUAL CELL ELEMENTS MOVING NWD ACROSS CNTRL AND NRN AZ THROUGH THIS EVENING...REF 2111 VALID THROUGH 21Z. ALTHOUGH INSTABILITY STILL REMAINS WEAK THIS AFTERNOON...FURTHER DESTABILIZATION REMAINS POSSIBLE OVER CNTRL AND NRN AZ AS A DRY SLOT EVIDENT ON WATER VAPOR IMAGERY OVER SRN CA AND WRN AZ ADVANCES NNEWD. MID-LEVEL LAPSE RATES ARE ALREADY STEEP AND CONTINUED SFC HEATING SHOULD HELP LOW-LEVEL LAPSE RATES TO STEEPEN FURTHER LATE THIS AFTERNOON. THIS COMBINED WITH 500 MB TEMPS OF -18 TO -20 C AND THE STRONG VERTICAL SHEAR ASSOCIATED WITH THE MID-LEVEL JET MAY RESULT IN SEVERE STORMS CAPABLE FOR HAIL AND ISOLATED WIND DAMAGE MAINLY LATE THIS AFTERNOON INTO EARLY THIS EVENING. ...LOWER TX COAST... SOUTHWEST FLOW ALOFT WILL REMAIN IN PLACE ACROSS SOUTH TX AS A WELL-DEVELOPED UPPER-LOW ADVANCES EWD ACROSS THE SWRN STATES TONIGHT. IN RESPONSE...A STRONG LOW-LEVEL JET IS FORECAST TO DEVELOP ACROSS THE SRN PLAINS AND THIS WILL HELP TO LIFT A WARM FRONT NNEWD ALONG THE LOWER TX COAST. STRONG LIFT ASSOCIATED WITH THE LOW-LEVEL JET SHOULD RESULT IN MCS DEVELOPMENT OVERNIGHT WITH STORM COVERAGE INCREASING FROM SOUTH TO NORTH ACROSS SOUTH TX AFTER MIDNIGHT. THE LOW-LEVEL JET WILL ALSO INCREASE SHEAR PROFILES WITH FORECAST SOUNDINGS LATE TONIGHT SHOWING 0-1 KM SHEAR VALUES REACHING ABOUT 25 KT ACROSS SOUTH TX. THIS COMBINED WITH SFC DEWPOINTS IN THE MID 70S F MAY RESULT IN AN ISOLATED TORNADO THREAT WITH ROTATING STORMS THAT MOVE NWD ACROSS THE REGION LATE TONIGHT. ..BROYLES.. 10/14/2006  From swody1 at goshenarc.org Sun Oct 15 00:45:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 20:45:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150047 SWODY1 SPC AC 150046 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0746 PM CDT SAT OCT 14 2006 VALID 150100Z - 151200Z ...NO SVR TSTM AREAS FORECAST... ...W TX... SCATTERED STRONG STORMS CONTINUE DEVELOPING WITHIN THE BROAD FETCH OF SUBTROPICAL MOISTURE AND LARGE SCALE ASCENT ACROSS W AND SWRN TX INTO SERN NM DOWNSTREAM FROM UPPER LOW OVER AZ. MODEST SELY LOW LEVEL FLOW BENEATH MODERATE 40-45 KT WLY MID LEVEL FLOW IS RESULTING IN SUFFICIENT DEEP LAYER SHEAR FOR SUPERCELLS. STRONGEST STORMS REMAIN OVER SWRN TX EARLY THIS EVENING WHERE THE BOUNDARY LAYER EXPERIENCED MORE HEATING EARLIER TODAY...RESULTING IN MLCAPE FROM 500 TO 800 J/KG. STORMS DEVELOPING FARTHER N ACROSS W TX ARE PROBABLY SLIGHTLY ELEVATED ABOVE A BOUNDARY LAYER THAT HAS BEEN RENDERED LESS UNSTABLE BY EXTENSIVE STRATUS. THE 00Z RAOB FROM AMARILLO CONFIRMS THE STABLE LAYER NEAR THE SURFACE IS RATHER SHALLOW IN THIS REGION. A SLY LOW LEVEL JET WILL STRENGTHEN OVER W TX THIS EVENING WITHIN ZONE OF HEIGHT FALLS DOWNSTREAM FROM UPPER LOW. HOWEVER...INSTABILITY WILL BECOME INCREASINGLY MARGINAL OVER SWRN TX AS THE BOUNDARY LAYER COOLS. PRIMARY THREAT APPEARS TO BE ISOLATED MARGINALLY SEVERE HAIL AND STRONG WIND GUSTS WITH ROTATING STORMS. OVERALL THREAT IS SOMEWHAT LIMITED BY WEAK INSTABILITY. ...SRN TX... SCATTERED CONVECTION WILL CONTINUE DEVELOPING PRIMARILY WITHIN ZONE OF LIFT ACCOMPANYING A NEWD EJECTING IMPULSE AND IN VICINITY OF WARM FRONT AS IT LIFTS SLOWLY NWD THROUGH SRN TX AND THE WRN GULF. AN ELY LOW LEVEL JET IS FORECAST TO STRENGTHEN IN THIS REGION LATER TONIGHT AND SHOULD AUGMENT LOW LEVEL SHEAR PROFILES. HOWEVER...FLOW IN THE 3-6 KM LAYER WILL REMAIN WEAK DUE TO PROXIMITY OF A BROAD UPPER RIDGE. THOUGH RICH LOW LEVEL MOISTURE IS IN PLACE...PRIMARY LIMITING FACTOR FOR A MORE ROBUST SEVERE THREAT WILL BE WEAK LAPSE RATES AND INSTABILITY ASSOCIATED WITH DEEP MOIST ADIABATIC PROFILES. AN OUTSIDE CHANCE FOR AN ISOLATED TORNADO MAY EXIST LATER TONIGHT AS THE LOW LEVEL WIND PROFILES INCREASE. HOWEVER...OVERALL THREAT APPEARS LIMITED. ..DIAL.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 05:37:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 01:37:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150539 SWODY1 SPC AC 150537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1237 AM CDT SUN OCT 15 2006 VALID 151200Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE TX COASTAL AREA INTO SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SERN NM INTO WRN TX... ...SYNOPSIS... UPPER LOW CURRENTLY OVER AZ SHOULD ADVANCE EWD INTO ERN NM BY SUNDAY NIGHT AS AN UPSTREAM IMPULSE AMPLIFIES INTO THE PACIFIC NW. THE GFS IS A LITTLE FASTER THAN THE NAM IN EJECTING THIS SRN STREAM WAVE. POTENTIAL WILL ALSO EXIST FOR WEAKER IMPULSES TO EJECT NEWD AHEAD OF MAIN UPPER TROUGH. COASTAL FRONT OVER THE WRN GULF WILL LIFT NWD THROUGH SERN TX INTO SRN LA SUNDAY AND SUNDAY NIGHT AS A STRONG SLY LOW LEVEL JET DEVELOPS IN ADVANCE OF THE UPPER TROUGH. ...SERN TX THROUGH SRN LA... LOW LEVEL DEWPOINTS IN THE LOWER 70S OVER S TX WILL ADVECT NWD INTO PARTS OF SERN TX AND SRN LA SUNDAY AND SUNDAY NIGHT S OF RETREATING WARM FRONT. HOWEVER...INSTABILITY SHOULD REMAIN LIMITED DUE TO MOIST ADIABATIC PROFILES AND WIDESPREAD CLOUDS AND RAIN. SBCAPE FROM 500 TO 1000 J/KG WILL BE POSSIBLE AS LOW 70S DEWPOINTS ADVECT INLAND S OF RETREATING FRONT. SLY LOW LEVEL JET IS FORECAST TO STRENGTHEN TO IN EXCESS OF 50 KT OVER ERN TX SUNDAY AND SHIFT INTO LA SUNDAY NIGHT WITHIN ZONE OF HEIGHT FALLS DOWNSTREAM FROM UPPER TROUGH. DIFFERENCES EXIST BETWEEN THE NAM AND GFS IN HANDLING THE LOW LEVEL MASS FIELDS...WITH THE GFS BEING WEAKER AND DISPLACED FARTHER EAST WITH ITS LOW LEVEL JET. HOWEVER...OVERALL PATTERN WOULD SUGGEST 0-1 KM HODOGRAPHS MAY BECOME SUPPORTIVE OF LOW LEVEL MESOCYCLONES FROM SERN TX COAST INTO SRN LA WITHIN A MOIST LOW LEVEL THERMODYNAMIC ENVIRONMENT. CONVECTION WILL CONTINUE TO SPREAD NWD INTO SERN TX AND SRN LA SUNDAY AND SUNDAY NIGHT. POTENTIAL WILL EXIST FOR ISOLATED EMBEDDED SUPERCELLS WITHIN THE LARGER AREA OF CONVECTION AS LOW LEVEL WIND FIELDS STRENGTHEN...ESPECIALLY IF POCKETS OF HEATING CAN DEVELOP. MAIN THREAT WILL BE ISOLATED TORNADOES AND POSSIBLY DAMAGING WIND GUSTS. MARGINAL THERMODYNAMIC PROFILES WILL REMAIN THE PRIMARY LIMITING FACTOR. ...NM INTO FAR WRN TX... STEEPER MID LEVEL LAPSE RATES SHOULD SPREAD EWD THROUGH NM INTO FAR W TX ABOVE LOW LEVEL DEWPOINTS IN THE UPPER 50S TO LOWER 60S AS THE UPPER TROUGH ADVANCES EWD. SATELLITE IMAGERY SUGGESTS AN UPPER LEVEL DRY SLOT COULD SHIFT INTO PARTS OF ERN NM AND WRN TX AHEAD OF MAIN VORT MAX DURING THE AFTERNOON. HOWEVER...WITH LOW LEVEL FLOW EXPECTED TO REMAIN WEAK IN THIS REGION...LOW CLOUDS COULD BE SLOW TO MIX OUT. WHERE POCKETS OF HEATING CAN DEVELOP MLCAPE AROUND 1000 J/KG WILL BE POSSIBLE. IF SUFFICIENT DESTABILIZATION OCCURS...STORMS MAY INTENSIFY WITHIN ZONE OF CVA FROM NM INTO WRN TX DURING THE AFTERNOON AND EARLY EVENING. VERTICAL WIND PROFILES WILL WITH DEEP LAYER SHEAR FROM 50 TO 60 KT WILL SUPPORT SUPERCELL STORMS WITH LARGE HAIL THE PRIMARY THREAT. ..DIAL.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 12:34:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 08:34:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151235 SWODY1 SPC AC 151233 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0733 AM CDT SUN OCT 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER SERN NM AND SWRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MIDDLE/UPPER TX AND SWRN LA COAST... ...SERN NM/SWRN TX... MID LEVEL LAPSE RATES WILL STEEPEN AS STRONG ASCENT SPREADS FROM WEST TO EAST ACROSS THIS REGION TODAY AHEAD OF APPROACHING UPPER LOW. STORMS EARLY THIS MORNING HAVE ALREADY ORGANIZED INTO SMALL SUPERCELLS...INDICATING 500-1000 J/KG MUCAPE IS MORE THAN ADEQUATE FOR INTENSE/ORGANIZED STORMS GIVEN VERY STRONG DEEP LAYER SHEAR. FORECAST SOUNDINGS SUGGEST STORMS THIS MORNING REMAIN SLIGHTLY ELEVATED ABOVE A STABLE SURFACE LAYER...THOUGH LONGER-LIVED STORMS WILL BE CAPABLE OF MARGINALLY SEVERE HAIL AND ISOLATED STRONG/DAMAGING WINDS. EXPECT LACK OF MID/HIGH LEVEL CLOUDS WILL ALLOW SOME MIXING TO OCCUR OVER HIGHER TERRAIN OF FAR SWRN TX/SRN NM/NRN CHIHUAHUA TO THE SOUTH OF SURFACE FRONT NOW EXTENDING FROM W-CENTRAL TX SWWD INTO SWRN NM. WHERE POCKETS OF HEATING CAN OCCUR....MLCAPE FROM 500-1000 J/KG COULD DEVELOP ALONG NWRN EXTENT OF LOWER 60F SURFACE DEW POINT AXIS EXTENDING INTO SWRN TX/FAR SERN NM THIS AFTERNOON. EFFECTIVE SHEAR NEAR 50 KT WILL BE SUFFICIENT FOR A FEW SURFACE-BASED SUPERCELLS/ORGANIZED CLUSTERS THIS AFTERNOON AND EVENING. IF SUFFICIENT MLCAPE CAN DEVELOP...LARGE HAIL WILL BE PRIMARY SEVERE THREAT ALONG WITH ISOLATED DAMAGING WINDS. ...MIDDLE/UPPER TX COAST INTO SWRN LA... RICH TROPICAL MOISTURE CONTINUES TO LIFT NWD ACROSS THE WRN GULF OF MEXICO THIS MORNING WITH PW/S IN EXCESS OF 2 INCHES AND SURFACE DEW POINTS IN THE MID/UPPER 70S LIKELY SPREADING INTO THE UPPER TX/SWRN LA COAST TODAY. THIS WILL OCCUR UNDER INCREASING SLY H85 FLOW AHEAD OF APPROACHING MID/UPPER LOW NOW MOVING INTO THE SRN ROCKIES. MODELS ARE CONSISTENT IN DEVELOPING 50+ KT LLJ INTO SERN TX BY 00Z...WHICH STRENGTHENS TO NEAR 70 KT OVERNIGHT ACCORDING TO THE NAM/WRF. THUNDERSTORMS WILL STEADILY INCREASE INTO THE MIDDLE/UPPER TX COAST AND SWRN LA THROUGH THE DAY AND CONTINUE OVERNIGHT ALONG AND NORTH OF MARITIME WARM FRONT NOW DEVELOPING ALONG AND JUST OFF THE UPPER TX COAST. THOUGH DEEP MOIST PROFILES WILL LIMIT AVAILABLE INSTABILITY....RICH LOW LEVEL MOISTURE AND TEMPERATURES APPROACHING THE LOWER 80S SHOULD BE COMMON BEHIND THIS WARM FRONT. THIS IS EXPECTED TO RESULT IN MARGINAL SURFACE-BASED INSTABILITY WITHIN EXTREME LOW LEVEL SHEAR AND HIGH VALUES OF BOUNDARY LAYER RELATIVE HUMIDITY. THIS WILL SUPPORT AN INCREASINGLY FAVORABLE ENVIRONMENT FOR LOW LEVEL ROTATION WHERE POCKETS OF SURFACE-BASED CAPE CAN MAXIMIZE...ESPECIALLY LATER TODAY AND TONIGHT UNDER STRENGTHENING LLJ AXIS. FAST MOVING SMALL LINES AND SUPERCELLS ARE EXPECTED TO DEVELOP DURING THIS PERIOD WITH ATTENDANT THREATS OF DAMAGING WINDS AND ISOLATED TORNADOES. ..EVANS/GUYER.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 16:29:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 12:29:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151632 SWODY1 SPC AC 151630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT SUN OCT 15 2006 VALID 151630Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF NM AND W TX... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SE TX AND SW LA... ...SYNOPSIS... AZ UPR LOW APPEARS TO HAVE REACHED ABOUT MAXIMUM INTENSITY AND SHOULD BEGIN TO DEAMPLIFY AS IT CONTINUES SLOWLY E OR ESE INTO SW NM LATER TODAY. DOWNSTREAM FROM THE LOW...EXPECT MID LEVEL SWLY FLOW TO SLOWLY STRENGTHEN FROM W TO E ACROSS TX THROUGH 12Z MONDAY. AT THE SURFACE...DIFFUSE WARM FRONT SHOULD LIFT FARTHER N ACROSS SE TX/CSTL LA TODAY/TONIGHT...WHILE WEAK INVERTED TROUGH HOLDS MORE OR LESS STATIONARY FROM THE TX S PLNS ENE INTO N CNTRL TX. ...SRN AND ERN NM/W TX... SCTD STRONG TO SEVERE STORMS/SUPERCELLS EXPECTED TO PERSIST THROUGH TONIGHT/EARLY MONDAY INVOF WSW/ENE ORIENTED SURFACE TROUGH EXTENDING FROM SRN NM INTO NW/N CNTRL TX. MODERATE BUT VERY MOIST /850 MB DEWPOINTS AOA 15 C/ SLY LOW LEVEL FLOW WILL CONTINUE BENEATH 40-50 KT SW FLOW DOWNSTREAM FROM AZ LOW. WHILE NO DISTINGUISHABLE SHORTWAVE IMPULSES ARE APPARENT IN SATELLITE IMAGERY...GENERAL LARGE SCALE ASCENT SHOULD MAINTAIN FAVORABLE ENVIRONMENT FOR STORM DEVELOPMENT AS LOW CONTINUES EWD. ACTIVITY MAY BE ENHANCED LATER TODAY ACROSS SRN NM AND FAR W TX BY HEATING OVER HIGHER TERRAIN. LARGE HAIL SHOULD BE THE MAIN SEVERE THREAT...ALTHOUGH LOCALLY DAMAGING WIND AND AN ISOLATED TORNADO COULD OCCUR WITH STRONGER/MORE SUSTAINED UPDRAFTS. ...SE TX/SW LA... VERY RICH TROPICAL MOISTURE /850 MB DEWPOINTS ABOVE 16 C/ WILL CONTINUE TO STREAM NWD INTO SE TX AND EVENTUALLY SRN LA THIS PERIOD AS MARITIME WARM FRONT LIFTS FARTHER N. SHORTWAVE FORCING FOR ASCENT WILL REMAIN WEAK...AND MID LEVEL LAPSE RATES WILL REMAIN NEAR MOIST ADIABATIC. BUT GENERAL AREA OF UPR DIFFLUENCE DOWNSTREAM FROM DISTURBANCES OVER MEXICO AND THE WRN GULF...ALONG WITH LOW LEVEL WARM ADVECTION...SHOULD MAINTAIN GOOD SETUP FOR SHOWERS/STORMS NOW OVER THE NWRN GULF TO MOVE/DEVELOP N ACROSS THE SE TX CSTL PLN. GIVEN RICH MOIST ENVIRONMENT...EXPECTED STRENGTHENING OF LLJ DOWNSTREAM FROM EJECTING AZ LOW MAY FOSTER LOW LEVEL UPDRAFT ROTATION AND THE POTENTIAL FOR TORNADOES. THIS ACTIVITY MAY BEGIN AS SURFACE HEATING ENHANCES LOW LEVEL DESTABILIZATION LATER TODAY...BUT THE GREATEST THREAT MAY EVOLVE TONIGHT AND EARLY MONDAY AS SLY LLJ INCREASES TO AOA 50 KTS. ..CORFIDI/TAYLOR.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 19:48:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 15:48:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151950 SWODY1 SPC AC 151949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SUN OCT 15 2006 VALID 152000Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SE NM AND WEST TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF EAST TX AND LA... ...WEST TX/SE NM... AN UPPER-LOW OVER AZ WILL CONTINUE TO MOVE EWD TOWARD THE REGION THIS AFTERNOON. SCATTERED THUNDERSTORMS ARE ONGOING AHEAD OF A DRY SLOT EVIDENT ON WATER VAPOR OVER SRN NM. AS THIS FEATURE MOVES ENEWD...LARGE-SCALE ASCENT AHEAD OF THE UPPER-LOW WILL SUPPORT THE DEVELOPMENT OF NUMEROUS THUNDERSTORMS THIS AFTERNOON INTO THE OVERNIGHT PERIOD. LATEST SFC ANALYSIS SHOWS LOWER TO MID 60S F DEWPOINTS EXTENDING NEWD FROM FAR WEST TX ALONG THE ERN EDGE OF THE CAPROCK INTO THE SERN TX PANHANDLE. THUNDERSTORMS ARE DEVELOPING ON THE COOL SIDE OF THE MOISTURE GRADIENT WHERE FORCING WITH THE UPPER-TROUGH IS STRONGEST. THIS COMBINED WITH STRONG VERTICAL SHEAR WILL BE TWO FACTORS SUPPORTIVE OF SEVERE WEATHER THIS AFTERNOON. HAIL WILL BE POSSIBLE ESPECIALLY AS LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-TROUGH AND COOLER MID-LEVEL TEMPS MOVE EWD INTO WEST TX LATE THIS AFTERNOON. HAIL WILL BE MOST LIKELY WITH THE STRONGER THUNDERSTORMS THAT DEVELOP ALONG THE NWRN EDGE OF THE MOISTURE GRADIENT WHERE CONVECTIVE COVERAGE HAS BEEN MINIMAL AND INSTABILITY IS LOCALLY ENHANCED. ...EAST TX/LA... LATEST WATER VAPOR ANALYSIS SHOWS A VERY LARGE MCS JUST OFF THE TX COAST WITH MID-LEVEL MOISTURE INCREASING ALONG THE TX COAST FROM SOUTHWEST TO NORTHEAST. THIS MOISTURE COMBINED WITH THE EXPANDING LOW-LEVEL JET AND DESTABILIZATION SHOULD MAKE MCS DEVELOPMENT MORE LIKELY ACROSS THE TX COASTAL PLAINS LATE THIS AFTERNOON INTO THE EVENING. MODEL FORECASTS ARE CONSISTENT WITH AN MCS DEVELOPING AND MOVING NWD ACROSS EAST TX INTO WRN LA DURING THE OVERNIGHT PERIOD. THE LATEST WSR-88D VWPS FROM THE HOUSTON AREA SHOW IMPRESSIVE SHEAR PROFILES WITH STRONG VEERING WITH HEIGHT AND 0-1 KM SHEAR VALUES AROUND 30 KT. THIS SHOULD BE FAVORABLE FOR ROTATING STORMS MOVING NWD ACROSS THE REGION THIS AFTERNOON. AS THE LOW-LEVEL JET INTENSIFIES TO 60-70 KT ACROSS EAST TX TONIGHT...THE TORNADO THREAT SHOULD INCREASE AND GRADUALLY EXPAND NWD. ALTHOUGH TORNADOES SHOULD BE THE MOST LIKELY TYPE OF SEVERE WEATHER...THE HIGH SFC DEWPOINTS AND STRONG LOW-LEVEL FLOW MAY BE SUPPORTIVE OF A FEW DAMAGING WIND GUSTS DURING THE OVERNIGHT PERIOD AS WELL. ..BROYLES.. 10/15/2006  From swody1 at goshenarc.org Mon Oct 16 00:53:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 20:53:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160055 SWODY1 SPC AC 160053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT SUN OCT 15 2006 VALID 160100Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SOUTHEAST NM AND WEST TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF SOUTHEAST TX AND WESTERN LA... ...SOUTHWEST NM/WEST INTO NORTHWEST TX... LARGE UPPER TROUGH OVER AZ/NM IS FORECAST TO SHIFT EASTWARD INTO TX TONIGHT...WITH STRONG FORCING FOR ASCENT OVERSPREADING MUCH OF WEST/CENTRAL TX. THIS WILL MAINTAIN SCATTERED THUNDERSTORM ACTIVITY ACROSS WEST TX OVERNIGHT. POCKETS OF DAYTIME HEATING ALLOWED AIR MASS SOUTH OF MAF TO BECOME MODERATELY UNSTABLE WITH TEMPERATURES IN THE MID 70S AND MLCAPE UP TO 500 J/KG. VERTICAL SHEAR PROFILES IN THIS AREA ARE FAVORABLE FOR SUPERCELLS AND ISOLATED TORNADOES. ALTHOUGH STORMS WILL LIKELY AFFECT REGION THROUGH THE EVENING... STORMS MAY BECOME PROGRESSIVELY MORE ELEVATED AS BOUNDARY LAYER COOLS. LARGE HAIL SHOULD BECOME THE MAIN THREAT AFTER 03Z. STORMS MAY ALSO EXPAND IN COVERAGE TONIGHT AND SPREAD NORTHEASTWARD TOWARD NORTHWEST TX/SOUTHWEST OK...WITH A CONTINUED THREAT OF MARGINALLY SEVERE HAIL. ...SOUTHEAST TX AND WESTERN LA... RADAR/SATELLITE IMAGERY CONTINUE TO SHOW VERY LARGE MCS OVER THE WESTERN GULF OF MEXICO SOUTH OF HOU. THIS CONVECTION AND ASSOCIATED WARM FRONT IS EXPECTED TO LIFT SLOWLY NORTHWARD OVERNIGHT...MOVING ONSHORE ALONG THE UPPER TX AND SOUTHWEST LA COAST. MODELS ARE IN GENERAL AGREEMENT THAT SOUTHERLY LOW LEVEL JET WILL STRENGTHEN TO OVER 50 KNOTS AFTER 06Z IN THIS REGION. VERY MOIST LOW LEVEL AIR MASS /DEWPOINTS IN THE MID 70S/...COUPLED WITH INCREASING LOW LEVEL VERTICAL SHEAR PROFILES SUGGEST A THREAT OF ISOLATED SUPERCELLS EMBEDDED WITHIN LARGER RAIN SHIELD. THIS PSEUDO-TROPICAL SITUATION COULD RESULT IN ISOLATED TORNADOES AND DAMAGING WINDS OVERNIGHT IN STRONGER CELLS...PRIMARILY NEAR THE COAST. ..HART.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 05:27:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 01:27:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160529 SWODY1 SPC AC 160528 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1228 AM CDT MON OCT 16 2006 VALID 161200Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL TX INTO PARTS OF AR/MS AND WESTERN AL... LARGE UPPER LOW CURRENTLY OVER EASTERN AZ/WESTERN NM IS FORECAST TO BECOME AN OPEN WAVE AND PROPAGATE RAPIDLY NORTHEASTWARD ACROSS TX AND INTO THE MID MS VALLEY BY LATE MONDAY NIGHT. MEANWHILE...VERY STRONG SOUTHERLY LOW LEVEL JET /50-80 KNOTS/ WILL DEVELOP FROM LA INTO MO/IL. THIS WILL RESULT IN A ZONE OF KINEMATIC FIELDS VERY FAVORABLE FOR SEVERE THUNDERSTORMS ON MONDAY FROM EAST TX INTO THE CENTRAL GULF COAST STATES. THE MAIN FORECAST PROBLEM WILL BE THE EVOLUTION OF LOW LEVEL MOISTURE/INSTABILITY AND THE POTENTIAL FOR SURFACE-BASED STORMS. ...ARKLATEX REGION INTO CENTRAL GULF COAST STATES... CURRENTLY RADAR/SATELLITE IMAGERY SHOWS LARGE TROPICAL-LIKE MCS ALONG THE UPPER TX GULF COAST. SEVERAL SUPERCELLS ARE EMBEDDED WITH THIS ACTIVITY...WHICH WILL MOVE ONSHORE BEFORE DAYBREAK. FORECAST SOUNDINGS ACROSS THIS AREA SHOW RAPIDLY STRENGTHENING LOW LEVEL WINDS ACROSS EAST TX AND MUCH OF LA /3KM SR-HELICITY VALUES OF 400-1000 M2/S2 CO-LOCATED WITH DEWPOINTS AOA 70F/...SUGGESTING THAT THREAT FOR ISOLATED TORNADOES AND GUSTY/DAMAGING WINDS WILL ONLY INCREASE THROUGH THE DAY AS MCS MOVES NORTHWARD TOWARD THE MEM AREA. LACK OF STRONG INSTABILITY AND ONLY MARGINAL MID LEVEL LAPSE RATES SUGGEST THAT AREAL COVERAGE OF SEVERE STORMS WILL BE RATHER LOW. HOWEVER...STRENGTH OF WIND FIELDS...TROPICAL AIRMASS...AND APPROACHING UPPER TROUGH INDICATE THE POTENTIAL FOR A FEW TORNADOES DESPITE WEAK INSTABILITY. EXTENT OF THREAT WILL ALSO BE MODULATED BY HOW FAR NORTHEAST THE RICH MOISTURE WILL MAKE IT INTO AR/TN/MS. THIS AREA WILL BE MONITORED DURING LATER UPDATES FOR THE POTENTIAL OF GREATER DESTABILIZATION AND A POSSIBLE UPGRADE. ...CENTRAL-NORTHEAST TX... SOME DAYTIME HEATING WILL BE POSSIBLE ALONG WEST EDGE OF PLUME OF DEEP CLOUDS/MOISTURE...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE OVER PARTS OF CENTRAL TX. COOLING TEMPERATURES ALOFT AND STEEPENING LAPSE RATES WILL PROMOTE SCATTERED THUNDERSTORM DEVELOPMENT BY MID AFTERNOON ROUGHLY ALONG A DRT-ACT AXIS. DEEP LAYER EFFECTIVE SHEAR IN THIS REGION WILL SUPPORT SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. ACTIVITY IS EXPECTED TO SPREAD EAST-NORTHEASTWARD DURING THE EVENING...PROVIDING PARTS OF NORTHEAST TX WITH ANOTHER ROUND OF STRONG/SEVERE STORMS. ..HART/GUYER.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 12:23:08 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 08:23:08 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161225 SWODY1 SPC AC 161223 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0723 AM CDT MON OCT 16 2006 VALID 161300Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL TX INTO THE CENTRAL GULF COAST/MID SOUTH... ...SYNOPSIS... UPPER TROUGH NOW MOVING INTO THE SRN HIGH PLAINS WILL EJECT RAPIDLY TODAY AND TONIGHT AS A NEGATIVELY-TILTED SHORTWAVE TROUGH INTO THE MID SOUTH. AHEAD OF THIS FEATURE...SURFACE LOW CENTER NEAR JCT AT 11Z IS EXPECTED TO LIFT NEWD INTO NERN TX ALONG QUASI-STATIONARY FRONT/TROUGH NOW EXTENDING TOWARDS TKX/CENTRAL AR WITH LOW CENTER EXPECTED TO WEAKEN AS IT LIFTS TOWARDS THE MID SOUTH LATER TONIGHT. A PAIR OF WARM FRONTS HAVE EVOLVED EARLY THIS MORNING ACROSS THE TX/LA COAST WITH PRIMARY MARINE FRONT ANALYZED FROM CENTRAL TX NEWD INTO FAR SERN LA AT 11Z...WHILE SECONDARY WARM FRONT DEVELOPING FROM THE MS COAST NWWD TO NEAR TKX. IN ADDITION...WEAK COLD FRONT IS EXPECTED TO BECOME BETTER DEFINED TO THE S-SW OF NEWD MOVING LOW CENTER...THOUGH FRONT WILL LIKELY MOVE VERY LITTLE AND PERHAPS STALL FROM NERN INTO CENTRAL TX TODAY. THIS WILL LEAVE A VERY MOIST AIR MASS IN PLACE THROUGH THE PERIOD FROM THE TX COAST INTO THE LOWER MS RIVER VALLEY. ...SERN TX INTO THE LOWER MS RIVER VALLEY... SUPERCELLS HAVE REMAINED INTENSE WITH PERSISTENT LOW LEVEL ROTATION FROM THE UPPER TX COAST INTO SRN LA/FAR SRN MS EARLY THIS MORNING... ESPECIALLY NEAR THE MARINE FRONT. AREA VWP/S SUPPORT MODEL GUIDANCE IN SUSTAINING VERY STRONG LLJ ACROSS THIS REGION FOR MUCH OF THE DAY...WITH 11Z WNF PROFILER REVEALING 70 KT WINDS AT 1KM. THIS LEAVES EXTREME LOW LEVEL SHEAR / EVIDENT THIS MORNING WITH OBSERVED 0-1 KM SRH IN EXCESS OF 400 M2/S2 AT KHGX AND KLCH / OVERSPREADING A RICH TROPICAL BOUNDARY LAYER CHARACTERIZED BY SURFACE DEW POINTS IN THE MID/UPPER 70S. WITH DIURNAL HEATING INCREASING POTENTIAL FOR ROTATING STORMS TO ROOT INTO THIS RICH BOUNDARY LAYER...TORNADO THREAT WILL REMAIN ENHANCED OVER THE REGION AND ISOLATED SIGNIFICANT TORNADOES MAY OCCUR. THE LLJ WILL GRADUALLY VEER AND 50-70 KT MAXIMUM IS FORECAST TO LIFT NNEWD INTO THE TN VALLEY LATER THIS EVENING. HOWEVER...CONTINUED FEED OF TROPICAL AIR OFF THE GULF COULD SUSTAIN A TORNADO THREAT ALONG THE GULF COAST FOR MUCH OF THE PERIOD AS FORECAST SOUNDINGS MAINTAIN SFC-1 KM SRH IN EXCESS OF 150 M2/S2 UNDER 40+ KT SSWLY H85 FLOW THROUGH AT LEAST 06Z TONIGHT. ...CENTRAL TX INTO THE MID SOUTH... SEVERE THREAT WILL BECOME MORE CONDITIONAL AWAY FROM THE GULF AS INSTABILITY REMAINS WEAKER. HOWEVER...SURFACE DEWPOINTS NEAR 70F AND EXTREME SHEAR WILL CONTINUE AHEAD OF EJECTING UPPER WAVE AND ASSOCIATED LOW CENTER THROUGH THE PERIOD FROM CENTRAL TX INTO THE MID SOUTH. SMALL LINES AND SUPERCELLS WILL LIKELY EVOLVE THROUGH THE DAY AND MOVE RAPIDLY NEWD...WITH SEVERE THREAT INCREASING WHERE HEATING CAN MIX INTO VERY MOIST SURFACE LAYER. PRIMARY SEVERE THREAT MAY BE FROM LARGE HAIL AS STORMS REMAIN SLIGHTLY ELEVATED ACROSS TX INTO THE EARLY AFTERNOON. HOWEVER...ONCE SUFFICIENT MIXING OCCURS DAMAGING WIND AND ISOLATED TORNADO THREAT WILL LIKEWISE INCREASE. ..EVANS/GUYER.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 16:29:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 12:29:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161631 SWODY1 SPC AC 161629 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1129 AM CDT MON OCT 16 2006 VALID 161630Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT FROM SE TX INTO THE LOWER MS VALLEY... ...SE TX TO THE LOWER MS VALLEY... A MID LEVEL SHORTWAVE TROUGH OVER ERN NM/W TX WILL EJECT ENEWD OVER THE SRN PLAINS TO AR AND WRN TN/KY BY LATE TONIGHT AS A LARGER SCALE TROUGH DIGS SEWD OVER THE GREAT BASIN. A SURFACE LOW NOW IN NE TX WILL DEVELOP NEWD IN ADVANCE OF THIS EJECTING MID LEVEL WAVE...WHILE THE STRONG LLJ WILL ALSO DEVELOP NEWD FROM LA TOWARD THE TN/OH VALLEYS BY TONIGHT. EXPECT WIDESPREAD CONVECTION TO PERSIST THROUGH THE DAY OVER SE TX AND THE LOWER MS VALLEY ALONG A SURFACE WARM FRONT WHICH IS LIFTING SLOWLY NWD. REGIONAL SOUNDINGS...PROFILERS...AND VWP/S SHOW INTENSE LOW-LEVEL SHEAR /0-1 KM SRH OF 400-700 M2/S2/ WITH THE 50-70 KT LLJ...ESPECIALLY OVER SRN/CENTRAL LA ATTM. DEEP LAYER VERTICAL SHEAR HAS ALSO INCREASED OVER THIS AREA THE PAST SEVERAL HOURS. DESPITE WARM MID LEVEL TEMPERATURES AND POOR LAPSE RATES...BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 70S ARE DRIVING SURFACE-BASED INSTABILITY ALONG AND S OF THE MARINE FRONT. THE MARINE FRONT SHOULD CONTINUE TO LIFT SLOWLY NWD TOWARD THE I-20 CORRIDOR ACROSS LA/MS DURING THE AFTERNOON...WHILE THE LLJ CORE DEVELOPS NEWD INTO MS. THUS...EXPECT THE PRIMARY SUPERCELL TORNADO THREAT AREA TO SHIFT NEWD FROM SE TX/SRN LA THIS MORNING TO CENTRAL/NE LA AND SRN/CENTRAL MS BY LATER THIS AFTERNOON/EVENING. ..THOMPSON/TAYLOR.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 20:00:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 16:00:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 162002 SWODY1 SPC AC 162000 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0300 PM CDT MON OCT 16 2006 VALID 162000Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS SE TX TO N-CENTRAL MS AND WRN AL... ...SYNOPSIS... AS WRN CONUS SYNOPTIC TROUGH AMPLIFIES AND MOVES SEWD...STRONG SHORTWAVE TROUGH NOW OVER SRN PLAINS WILL EJECT NEWD...REACHING VICINITY LOWER-MID MS VALLEY BY END OF PERIOD. ASSOCIATED ENHANCED GRADIENTS ALOFT...ALONG WITH LOW LEVEL WAA AND MOISTURE TRANSPORT REGIME...WILL SPREAD ENEWD ACROSS DEEP S IN SUPPORT OF SVR TSTM POTENTIAL. WEAK SFC LOW OVER ARKLATEX REGION SHOULD LIFT NEWD OVER AR. MARINE/WARM FRONT IS ANALYZED ALONG SRN RIM OF LARGE AREA OF PRECIP...FROM SE TX EWD ACROSS CENTRAL LA TO SWRN MS...THEN SEWD TO NEAR COASTAL MS/AL BORDER. THIS FRONT SHOULD LIFT NWD OVER CENTRAL MS AND PORTIONS WRN/SRN AL BEFORE 17/12Z. ...SE TX TO MS/WRN AL... OUTLOOK IS MOST STRONGLY DRIVEN BY SUPERCELLULAR TORNADO THREAT...WITH DAMAGING DOWNDRAFT GUSTS ALSO POSSIBLE FROM EITHER SUPERCELLS OR SMALL BOWS. MARINE FRONT WILL SHIFT SLOWLY NWD ACROSS LA/MS DURING NEXT SEVERAL HOURS...DEMARCATING NRN PORTION OF FAVORABLY BUOYANT ENVIRONMENT. FAVORABLY STRONG LOW LEVEL HODOGRAPHS AND DEEP-LAYER SHEAR ARE EVIDENT BOTH ALONG MARINE FRONT AND WELL SWD INTO WARM SECTOR...AS SAMPLED BY 18Z SIL SOUNDING. REF SPC WWS 830/831...AS WELL AS RELATED MESOSCALE DISCUSSIONS...FOR MORE DETAILED REASONING OF NOWCAST SCENARIO. ASSOCIATED REGIME OF ENLARGED LOW LEVEL HODOGRAPHS...FAVORABLE DEEP-LAYER BULK SHEAR AND AT LEAST MRGL BUOYANCY...IS FCST TO SHIFT ENEWD THIS EVENING AND OVERNIGHT ACROSS MORE OF MS AND SRN/WRN AL. THIS WILL CORRESPOND TO AREAS ALONG AND S OF MARINE FRONT...WHICH SHOULD LIE CLOSE TO 73-74 DEG F SFC ISODROSOTHERM. IN THIS AIR MASS...EXPECT NOCTURNAL/DIABATIC COOLING WILL BE TOO WEAK TO CAUSE ENOUGH STABILIZATION TO RAISE EFFECTIVE PARCELS ABOVE SFC. THEREFORE...GIVEN FCST FAVORABLE SHEAR PROFILES...SUPERCELLS WILL CONTINUE TO DEVELOP...ALONG WITH OCCASIONAL TORNADOES -- A FEW OF WHICH MAY PRODUCE SIGNIFICANT DAMAGE. MODIFIED RAOBS AND MODEL SOUNDINGS SUGGEST MUCAPES UP TO 1000 J/KG AFTER DARK AND 0-1 KM SRH UP TO AROUND 500 J/KG. ..EDWARDS.. 10/16/2006  From swody1 at goshenarc.org Tue Oct 17 00:41:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 20:41:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170043 SWODY1 SPC AC 170041 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 PM CDT MON OCT 16 2006 VALID 170100Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE CENTRAL GULF STATES... ...CENTRAL GULF STATES... SFC LOW CONTINUES TO LIFT NEWD ACROSS NERN AR IN RESPONSE TO EJECTING UPPER SHORTWAVE TROUGH. JUST DOWNSTREAM...TRUE WARM SECTOR RECOVERY HAS STRUGGLED TO RETURN NWD HOWEVER AS STRONG LOW LEVEL WARM ADVECTION AND WIDESPREAD PRECIPITATION MAINTAIN STABLE BOUNDARY LAYER AIRMASS ACROSS THE NERN HALF OF AL INTO NRN MS. ALTHOUGH INTENSE LOW LEVEL SHEAR EXISTS ALONG/NORTH OF BOUNDARY...UPDRAFT STRENGTH IS SOMEWHAT LACKING DUE TO MEAGER INSTABILITY. HOWEVER...JUST SOUTH OF THE WARM FRONT SUFFICIENT INSTABILITY EXISTS FOR ROBUST UPDRAFTS WHICH AT TIMES APPEAR TO TAKE ADVANTAGE OF STRONG LOW LEVEL SHEAR...AS EVIDENT BY PERIODIC TORNADIC SIGNATURES WITH NWD-MOVING SUPERCELLS WELL AHEAD OF ADVANCING COLD FRONT. THESE TRENDS WILL CONTINUE THROUGH THE EVENING WITH THE MOST PRONOUNCED TORNADO THREAT EXPECTED TO PERSIST WITHIN MORE DISCRETE SUPERCELLS AHEAD OF FORCED LINE OF STORMS THAT IS MOVING EWD ACROSS LA INTO WRN MS. SHEAR PROFILES ARE QUITE IMPRESSIVE ACROSS MUCH OF THE REGION WHICH FAVOR RAPID...AND POSSIBLY STRONG...TORNADIC DEVELOPMENT WITH ANY SUSTAINED SUPERCELL STRUCTURES. OTHERWISE...GUSTY WINDS MAY ACCOMPANY THE FORCED LINE OF STORMS AS THEY PROGRESS EWD DURING THE OVERNIGHT HOURS. ...ELSEWHERE... 00Z SOUNDING FROM GJT SUPPORTS ONGOING CONVECTIVE ACTIVITY ALONG COLD FRONT AS IT SURGES SEWD ACROSS THE CNTRL ROCKIES TONIGHT. STEEP LAPSE RATE ENVIRONMENT WILL GRADUALLY WANE WITH LOSS OF BOUNDARY LAYER HEATING AND UPDRAFT STRENGTH SHOULD ALSO REFLECT THIS INSTABILITY LOSS WITH GRADUALLY WEAKENING TRENDS AFTER SUNSET. ..DARROW.. 10/17/2006  From swody1 at goshenarc.org Fri Oct 20 12:44:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 08:44:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201246 SWODY1 SPC AC 201244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT FRI OCT 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NJ INTO SRN/ERN NEW ENGLAND... ...SYNOPSIS... BROAD CYCLONIC FLOW WILL PREVAIL OVER THE LWR 48 THIS PERIOD... DOWNSTREAM FROM E PACIFIC RIDGE. FAST-MOVING SHORTWAVE TROUGH NOW OVER THE UPR OH VLY EXPECTED TO AMPLIFY INTO A POTENT NEGATIVE-TILT IMPULSE OVER SRN NEW ENGLAND LATER TODAY AS SYSTEM CONTINUES TO MERGE WITH SHORTWAVE THAT CROSSED THE MID MS VLY YESTERDAY. FARTHER W...STRONG SPEED MAX NOW ENTERING ID SHOULD ALSO FURTHER AMPLIFY AS IT CONTINUES SE ACROSS THE CNTRL RCKYS LATER TODAY/EARLY SATURDAY. AT THE SFC...LOW NOW CONSOLIDATING IN S CNTRL PA EXPECTED TO STRENGTHEN SUBSTANTIALLY LATER TODAY/TONIGHT AS IT CROSSES SRN NEW ENGLAND AND THEN TURNS MORE NEWD ACROSS DOWNEAST ME. IN THE PLAINS...MT COLD FRONT SHOULD ACCELERATE SE AND OVERTAKE LEE TROUGH OVER S CNTRL NEB/NRN AND WRN KS. ...NJ INTO SRN/ERN NEW ENGLAND... OVERNIGHT SHOWERS IN THE MID ATLANTIC REGION APPEAR TO HAVE BEEN ASSOCIATED WITH LEAD IMPULSE BEING ABSORBED INTO STRONGER SHORTWAVE APPROACHING FROM THE OH VLY. THIS CONVECTION HAS SERVED TO MOISTEN THE BOUNDARY LAYER...AND SHOULD CONTINUE NE ACROSS SRN NEW ENGLAND AND OFF THE MID ATLANTIC CST LATER TODAY. IN WAKE OF THE SHOWERS...MODEST SURFACE HEATING SHOULD OCCUR AHEAD OF COLD FRONT ASSOCIATED WITH STRENGTHENING PA SFC LOW. WHILE MID LEVEL LAPSE RATES LIKELY WILL REMAIN WEAK AND SURFACE HEATING WILL BE LIMITED...COMBINATION OF EVEN MODERATE DIURNAL HEATING WITH STRONG DPVA...FRONTAL ASCENT AND MOIST LOW LEVEL ENVIRONMENT SHOULD SUPPORT DEVELOPMENT OF LOW-TOPPED CONVECTION/ POSSIBLE TSTMS ALONG AND JUST AHEAD OF COLD FRONT. WHILE THE STORMS MAY FORM AS FAR W AS ERN PA OR NJ...MORE SUBSTANTIAL ACTIVITY MAY NOT OCCUR UNTIL FRONT PASSES THE NYC AREA EARLY IN THE AFTN. RAPIDLY STRENGTHENING LOW TO MID LEVEL WIND FIELD /WITH 500 MB SPEEDS INCREASING TO AOA 60 KTS/ AND LINEAR FORCING MAY SUPPORT DEVELOPMENT OF A NARROW SQLN...WITH EMBEDDED SMALL SCALE BOWS/ ROTATING STORMS PRODUCING HIGH WIND AND POSSIBLY ONE OR TWO TORNADOES. THIS THREAT MAY REACH INTO THE CSTL ME AREA BY EVENING AS UPR SYSTEM ASSUMES A NEGATIVE TILT AND SFC LOW DEEPENS NEWD. ...CNTRL PLNS... SURFACE HEATING...CONVERGENCE ALONG LEE TROUGH/COLD FRONT AND ASCENT ASSOCIATED WITH APPROACHING/AMPLIFYING UPR TROUGH MAY SUPPORT THE DEVELOPMENT OF SCATTERED HIGH-BASED STORMS FROM SRN/CNTRL NEB INTO WRN/NRN KS. DEEPLY MIXED ENVIRONMENT WITH MODERATE UNIDIRECTIONAL WNWLY FLOW MAY SUPPORT MARGINALLY SEVERE HAIL AND GUSTY WINDS FOR A BRIEF PERIOD EARLY THIS EVENING. ..CORFIDI/CROSBIE.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 16:02:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 12:02:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201603 SWODY1 SPC AC 201602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1102 AM CDT FRI OCT 20 2006 VALID 201630Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NJ INTO SRN/ERN NEW ENGLAND... ...NJ INTO SRN/ERN NEW ENGLAND... SURFACE LOW DEEPENING UNDERWAY ACROSS ERN PA IN RESPONSE TO THE VIGOROUS UPPER S/WV TROUGH NOW INTO WRN PA. A STRONGLY FORCED LINE OF LOW TOPPED CONVECTION HAS DEVELOPED FROM THE SURFACE LOW SWD TO DCA AT 15Z VICINITY OF THE COLD FRONT. GENERALLY WEAK LAPSE RATES AND THE EXPECTED LITTLE SURFACE HEATING AHEAD OF THE LINE WILL LIMIT INSTABILITY AVAILABLE FOR DEEP CONVECTION TODAY. AS THE 90 PLUS KT 500 MB WIND MAX AND MID LEVEL COOLING ROTATE ACROSS NJ INTO SRN ENGLAND LATER THIS AFTERNOON...ALONG WITH THE RAPIDLY DEEPENING SURFACE LOW...SURFACE WINDS ASSOCIATED WITH THE CURRENT LINE OF CONVECTION WILL INCREASE ALONG WITH POTENTIAL FOR DAMAGING WINDS. BY 19Z THE LINE WILL BE PASSING THRU NYC SWD TO OFFSHORE NJ. WINDS AT ALL LEVELS WILL CONTINUE TO INCREASE THRU THE AFTERNOON AND EVENING WITH SURFACE LOW DEEPENING NEWD THRU INTERIOR NEW ENGLAND. THE POTENTIAL FOR DAMAGING WINDS WITH THE LOW TOPPED LINE OF CONVECTION EXPECTED TO SPREAD NEWD AHEAD OF SURFACE LOW...WITH GREATEST POTENTIAL VICINITY OF WARM FRONT. THE WARM FRONT CURRENTLY EXTENDS FROM LOW IN ERN PA NEWD ACROSS SERN NY/WRN MA TO VICINITY PWM. FRONT WILL CONTINUE TO SHIFT NWD INTO COASTAL AREAS OF MAINE DURING THE AFTERNOON PRIOR TO THE PASSAGE OF CONVECTIVE LINE. SINCE MLCAPE IS EXPECTED TO BE NO GREATER THAN 200 J/KG ANY DAMAGING WIND THREAT WILL BE PRIMARILY DRIVEN BY THE DOWNWARD TRANSFER OF THE STRONG WIND FIELDS WITH THE TROUGH AND INTENSIFYING SURFACE LOW ..HALES/GUYER.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 19:36:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 15:36:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201938 SWODY1 SPC AC 201937 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0237 PM CDT FRI OCT 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF CNTRL/SRN NEW ENGLAND... 19Z SFC ANALYSIS PLACES A 987 MB LOW VCNTY KPSF WITH A WARM FRONT LOCATED ACROSS SRN VT AND NH INTO DOWNEAST MAINE. TO THE S...A SHARP COLD FRONT WAS SWEEPING EWD WITH AN ASSOCD LINE OF CONVECTION. THE LOW WILL CONTINUE TO DEEPEN THIS EVENING WHILE MOVING NEWD INTO CNTRL MAINE. THE TRAILING FRONT WILL MOVE ACROSS CNTRL/SRN NEW ENGLAND AND OFFSHORE LATER THIS AFTERNOON. STRONGLY FORCED LOW-TOPPED SQUALL LINE WAS MOVING ENEWD AT 40 KTS AND IS EXTRAPOLATED TO CNTRL MASS...CNTRL CT AND ERN LONG ISLAND BY 21Z AND INTO SERN MASS/KBOS BETWEEN 22-23Z. RECENT SOUNDING FROM A DESCENDING AIRCRAFT INTO KPHL JUST BEHIND THE SQUALL LINE COUPLED WITH KDIX 88D VWP SUGGEST THAT 50 KT WINDS WERE DOWN TO AROUND 1 KM AGL. GIVEN STRENGTHENING OF THE ATTENDANT UPPER SYSTEM AND CORRESPONDING ACCELERATION OF WIND FIELDS...CONVECTION WILL CONTINUE TO HAVE THE POTENTIAL FOR DAMAGING WIND GUSTS THROUGHOUT CNTRL/SRN NEW ENGLAND LATE AFTN/EARLY EVE...PARTICULARLY AT HIGHER ELEVATIONS. ..RACY.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 19:48:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 15:48:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201950 SWODY1 SPC AC 201948 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0248 PM CDT FRI OCT 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF CNTRL/SRN NEW ENGLAND... 19Z SFC ANALYSIS PLACES A 987 MB LOW VCNTY KPSF WITH A WARM FRONT LOCATED ACROSS SRN VT AND NH INTO DOWNEAST MAINE. TO THE S...A SHARP COLD FRONT WAS SWEEPING EWD WITH AN ASSOCD LINE OF CONVECTION. THE LOW WILL CONTINUE TO DEEPEN THIS EVENING WHILE MOVING NEWD INTO CNTRL MAINE. THE TRAILING FRONT WILL MOVE ACROSS CNTRL/SRN NEW ENGLAND AND OFFSHORE LATER THIS AFTERNOON. STRONGLY FORCED LOW-TOPPED SQUALL LINE WAS MOVING ENEWD AT 40 KTS AND IS EXTRAPOLATED TO CNTRL MASS...CNTRL CT AND ERN LONG ISLAND BY 21Z AND INTO SERN MASS/KBOS BETWEEN 22-23Z. RECENT SOUNDING FROM A DESCENDING AIRCRAFT INTO KPHL JUST BEHIND THE SQUALL LINE COUPLED WITH KDIX 88D VWP SUGGEST THAT 50 KT WINDS WERE DOWN TO AROUND 1 KM AGL. GIVEN STRENGTHENING OF THE ATTENDANT UPPER SYSTEM AND CORRESPONDING ACCELERATION OF WIND FIELDS...CONVECTION WILL CONTINUE TO HAVE THE POTENTIAL FOR DAMAGING WIND GUSTS THROUGHOUT CNTRL/SRN NEW ENGLAND LATE AFTN/EARLY EVE...PARTICULARLY AT HIGHER ELEVATIONS. ..RACY.. 10/20/2006  From swody1 at goshenarc.org Sat Oct 21 00:21:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 20:21:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210021 SWODY1 SPC AC 210020 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0720 PM CDT FRI OCT 20 2006 VALID 210100Z - 211200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... COMPACT UPPER LOW WILL MOVE ENEWD ACROSS NEW ENGLAND THROUGH THE REMAINDER OF THE PERIOD...ALONG WITH AN ASSOCIATED THREAT FOR A FEW LIGHTNING STRIKES EMBEDDED WITHIN AREA OF WIDESPREAD PRECIPITATION. FURTHER W...A SECOND UPPER TROUGH WILL CONTINUE DIGGING SSEWD ACROSS THE ROCKIES THROUGH THE END OF THE PERIOD. A LARGE AREA OF PRECIPITATION -- WITH ISOLATED/EMBEDDED THUNDERSTORMS -- IS OCCURRING WITHIN CYCLONIC FLOW AROUND THIS FEATURE FROM WRN MT SEWD ACROSS WY AND CO AND INTO THE CENTRAL PLAINS. THOUGH LIGHTNING SHOULD DIMINISH WITH THE LOSS OF DIURNAL HEATING...A FEW STRIKES MAY PERSIST THROUGH 21/12Z -- PARTICULARLY ACROSS KS AND VICINITY WITHIN AREA OF WARM ADVECTION ASSOCIATED WITH NOCTURNAL LOW-LEVEL JET. ..GOSS.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 05:34:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 01:34:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210536 SWODY1 SPC AC 210534 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1234 AM CDT SAT OCT 21 2006 VALID 211200Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... LARGE UPPER TROUGH IS FORECAST TO MOVE SLOWLY ACROSS THE CENTRAL CONUS THIS PERIOD...ACCOMPANIED BY 100 KT MID-LEVEL JET. AT THE SURFACE...FRONT NOW EXTENDING FROM FL INTO THE NRN GULF SHOULD RETREAT NWD INTO THE GULF COAST REGION DURING THE FIRST HALF OF THE PERIOD. MEANWHILE...SECOND FRONT -- WHICH IS FORECAST TO SURGE SWD ACROSS THE PLAINS/EWD ACROSS THE MS VALLEY -- SHOULD OVERTAKE THE GULF COAST FRONT THROUGH THE LATTER HALF OF THE PERIOD. ...GULF COAST REGION... WARM MOIST BOUNDARY LAYER SHOULD SPREAD ONSHORE OVER THE GULF COAST REGION DURING THE FIRST HALF OF THE PERIOD...AS WEAKENING FRONT RETREATS NWD AHEAD OF SECOND BOUNDARY SURGING SEWD ACROSS THE CENTRAL CONUS. DESPITE BOUNDARY-LAYER DEWPOINTS IN THE LOW 70S...WEAK LAPSE RATES WITHIN THE MOIST TROPICAL AIRMASS S OF RETREATING BOUNDARY SHOULD HINDER SIGNIFICANT WARM SECTOR DESTABILIZATION. IN ADDITION...THIS REGION WILL REMAIN S OF THE ANTICYCLONICALLY-CURVED MID/UPPER JET. RESULTING SUBSIDENCE COMBINED WITH THE GENERAL LACK OF FAVORABLE INSTABILITY WILL LIKELY LIMIT THE POTENTIAL FOR VIGOROUS UPDRAFTS. NONETHELESS...WITH 30 TO 40 KT WLY MID-LEVEL FLOW YIELDING DEEP-LAYER SHEAR OTHERWISE SUFFICIENT FOR ORGANIZED STORMS...WILL MAINTAIN A LOW-PROBABILITY SEVERE THREAT ACROSS THIS REGION. ..GOSS/TAYLOR.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 12:44:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 08:44:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211246 SWODY1 SPC AC 211244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT SAT OCT 21 2006 VALID 211300Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... BROAD UPR TROUGH WILL PERSIST OVER THE CNTRL AND ERN U.S. THROUGH SUNDAY AS RIDGE PROGRESSES TO THE PAC NW CST. SHORTWAVE IMPULSE NOW OVER CO SHOULD MOVE E ACROSS THE OZARKS AND MID MS VLY LATER TODAY/ TONIGHT AS ADDITIONAL SPEED MAXIMA DROP S INTO THE NRN AND CNTRL RCKYS. AT LOWER LEVELS...WRN PART OF FRONT EXTENDING FROM N CNTRL FL ACROSS THE NRN GULF OF MEXICO IS RETURNING NWD AS A WARM FRONT OVER THE NWRN GULF. THIS BOUNDARY SHOULD REACH CSTL SECTION OF SE TX AND SRN LA LATER TODAY AS COLD FRONT ASSOCIATED WITH CO DISTURBANCE ACCELERATES SE ACROSS THE SRN PLNS. THE COLD FRONT SHOULD OVERTAKE THE GULF BOUNDARY OVER THE LWR MS VLY DURING THE LATTER HALF OF THE PERIOD. ...GLF CST RGN... LATEST OBSERVATIONS SHOW WARM MOIST AIR SPREADING NNW ACROSS THE FAR NWRN GULF TOWARD THE MIDDLE AND UPR TX GULF CST. DEWPOINTS IN THE LOW 70S SHOULD LIFT N INTO THE IMMEDIATE CSTL SECTIONS OF SE TX LATER TODAY. ALONG WITH SURFACE HEATING...THIS WILL RESULT IN SOME LOW LEVEL DESTABILIZATION. MID LEVEL LAPSE RATES WILL...HOWEVER... REMAIN WEAK AS REGION WILL BE ON EQUATORWARD SIDE OF CYCLONICALLY- CURVED UPR JET. WHILE MODEST DESTABILIZATION AND WEAK FRONTAL UPLIFT MAY YIELD A FEW AFTN STORMS ALONG THE CSTL PLAIN...THE STRONGEST ACTIVITY SHOULD REMAIN OFFSHORE. LOW LEVEL SHEAR SHOULD REMAIN WEAK...BUT COUPLED WITH HIGH SURFACE DEWPOINTS...SETUP MAY SUPPORT AN ISOLATED TORNADO OR TWO. LATER THIS AFTN INTO TONIGHT...ADDITIONAL STORMS LIKELY WILL FORM ALONG AND BEHIND AFOREMENTIONED COLD FRONT AS IT ACCELERATES SE ACROSS E TX/LA AND MS. MUCH OF THIS ACTIVITY WILL EITHER BE ELEVATED OR WILL QUICKLY BECOME SO AS THE BOUNDARY UNDERCUTS DEVELOPING UPDRAFTS. PRESENCE OF 40+ KT DEEP WLY SHEAR ON SRN FRINGE OF CNTRL PLNS TROUGH AND RICH MOISTURE MAY...NEVERTHELESS ...SUPPORT A FEW CELLS WITH STRONG SURFACE WINDS DESPITE RELATIVELY WEAK FORCING FOR ASCENT. ..CORFIDI/TAYLOR.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 16:06:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 12:06:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211607 SWODY1 SPC AC 211606 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1106 AM CDT SAT OCT 21 2006 VALID 211630Z - 221200Z ...NO SVR TSTM AREAS FORECAST... BROAD UPPER TROUGH DOMINATES MUCH OF CONUS ACCOMPANIED BY A STRONG POLAR JET SHIFTING EWD ACROSS SRN/CENTRAL PLAINS TO OH VALLEY BY SUN AM. STALLED FRONTAL ZONE ALONG/JUST OFFSHORE GULF COAST WILL MOVE INLAND THIS AFTERNOON UPR TX/LA COAST. LOW/MID LEVEL WARM ADVECTION COUPLED WITH TROPICAL MOISTURE FLUX CURRENTLY RESULTING IN ELEVATED CONVECTION SPREADING NEWD ACROSS SERN TX. NEXT COLD FRONT CURRENTLY MOVING THRU OK/NWRN TX WILL CONTINUE SEWD TO OFFSHORE MUCH OF TX COAST BY 12Z SUN. WHILE DEEP LAYER SHEAR OF 40KTS AND MLCAPES CLIMBING TO NEAR 2000 J/KG COASTAL AREAS SERN TX/SRN LA SUFFICIENT FOR A SEVERE THUNDERSTORM THREAT.. THE WEAK LAPSE RATES AND MARGINAL LOW LEVEL SHEAR PRECLUDES MORE THAN A LOW RISK OF ISOLATED ROTATING STORMS. WARM...MOIST ADVECTION WILL SPREAD THUNDERSTORMS EWD ACROSS CENTRAL GULF COAST STATES THRU TONIGHT. ADDITIONALLY WITH THE COLD FRONT ENCOUNTERING THE GULF MOISTURE LATER TONIGHT...FRONTAL CONVERGENCE SHOULD FOCUS ADDITIONAL STORM DEVELOPMENT SRN TX INTO LA PRIOR TO MOVING OFFSHORE BY SUN AM. ..HALES/GUYER.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 19:36:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 15:36:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211937 SWODY1 SPC AC 211935 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0235 PM CDT SAT OCT 21 2006 VALID 212000Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...GULF COASTAL STATES... AT 19Z...A MARINE WARM FRONT WAS LOCATED ALONG THE IMMEDIATE OFFSHORE WATERS OF THE UPPER TX COAST AND LA. WARM/MOIST ADVECTION ABOVE THE RESIDUAL CONTINENTAL POLAR BOUNDARY LAYER INLAND WAS RESULTING IN ELEVATED TSTMS...LIKELY ROOTED JUST ABOVE 800 MB PER RUC SOUNDINGS. CLOUD-BEARING SHEAR WAS SUFFICIENT FOR STORMS TO ATTAIN BRIEF SUPERCELLULAR CHARACTERISTICS...BUT MEAGER LAPSE RATES /WARM NOSE AROUND H7/ WILL LIKELY CONTINUE TO BE A DETRIMENT TO ORGANIZED ROBUST STORMS. THE SMALL MCS WILL LIKELY EXPAND ENEWD ACROSS THE LWR MS VLY AND TOWARD THE SERN STATES BY 12Z SUNDAY. VEERING MEAN LAYER FLOW WILL NOT BE FAVORABLE FOR MARITIME TROPICAL AIR TO SURGE NWD AT LOCATIONS E OF THE MS RVR. AS A RESULT...THERMODYNAMIC PROFILES DO NOT APPEAR SUPPORTIVE FOR ORGANIZED SEVERE WEATHER. OVERNIGHT...OTHER STORMS ARE LIKELY TO FORM ALONG/AHEAD OF THE SEWD MOVING COLD FRONT ACROSS THE UPPER TX COAST AND SPREAD EWD INTO CNTRL/SRN LA. HERE...SLIGHTLY MORE UNSTABLE BOUNDARY LAYER WILL EXIST ALONG THE IMMEDIATE COAST AND ISOLD TSTMS MAY BECOME ROOTED CLOSER TO THE SFC AND PRODUCE DAMAGING WINDS. THE MAJORITY OF THE STORMS SHOULD REMAIN SUB-SEVERE...HOWEVER. ..RACY.. 10/21/2006  From swody1 at goshenarc.org Sun Oct 22 00:27:42 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 20:27:42 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220029 SWODY1 SPC AC 220027 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0727 PM CDT SAT OCT 21 2006 VALID 220100Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...CENTRAL GULF COAST REGION... MOIST BOUNDARY LAYER AIRMASS CONTINUES WORKING NWD INTO THE CENTRAL GULF COAST REGION...AHEAD OF WEAK SRN STREAM SHORT-WAVE TROUGH AND ASSOCIATED AREA OF SHOWERS AND THUNDERSTORMS NOW CROSSING THE LOWER MS VALLEY. DESPITE UPPER 60S TO LOW 70S DEWPOINTS NOW OVER SRN LA...EVENING RAOBS INDICATE A SURFACE-BASED STABLE LAYER REMAINS ACROSS MOST OF THE REGION AWAY FROM THE IMMEDIATE COAST. FURTHER...SOUNDINGS REVEAL WEAK LAPSE RATES ACROSS SERN LA...WHICH IS LIMITING DEGREE OF INSTABILITY. THEREFORE...HAIL THREAT IS LIKELY TO REMAIN MINIMAL ACROSS THIS REGION. SOUNDINGS AND AREA VWPS DO INDICATE SUFFICIENT VEERING WITH HEIGHT/DEEP-LAYER SHEAR FOR ORGANIZED/ROTATING STORMS. ONE STORM JUST S OF THE S CENTRAL LA COAST DID SHOW SUPERCELL CHARACTERISTICS OVER THE PAST HOUR...AND ADDITIONAL ROTATING STORMS ARE POSSIBLE -- PARTICULARLY FROM SERN LA THIS EVENING...AND THEN EWD ACROSS SRN MS/SRN AL/THE WRN FL PANHANDLE OVERNIGHT. THEREFORE...WILL MAINTAIN A SMALL/LOW-PROBABILITY SEVERE THREAT AREA...WHERE A LOCALLY-DAMAGING GUST OR A BRIEF/WEAK TORNADO WILL BE POSSIBLE. ..GOSS.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 05:42:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 01:42:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220543 SWODY1 SPC AC 220541 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1241 AM CDT SUN OCT 22 2006 VALID 221200Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... LARGE UPPER TROUGH WILL CONTINUE MOVING SLOWLY EWD ACROSS THE CENTRAL AND ERN CONUS THIS PERIOD...ACCOMPANIED BY A LARGE/STRONG CYCLONIC JET STREAK. AT THE SURFACE...ASSOCIATED BAROCLINIC ZONE WILL CONTINUE SURGING SEWD INTO THE GULF OF MEXICO AND EWD ACROSS THE APPALACHIANS TOWARD THE ATLANTIC COAST THROUGH THE DAY. BY THE END OF THE PERIOD...THE FRONT SHOULD EXTEND FROM WELL OFF THE ATLANTIC COAST SWWD ACROSS CENTRAL FL AND INTO THE SRN GULF OF MEXICO. SHOWERS AND A FEW THUNDERSTORMS MAY BE ONGOING AT THE START OF THE PERIOD OVER THE SOUTHEAST AHEAD OF THIS FRONT...AND ISOLATED CONVECTION MAY DEVELOP NWD ALONG THE CAROLINA COAST AHEAD OF THE FRONT DURING THE DAY. HOWEVER...LACK OF INSTABILITY SUGGESTS THAT STORMS SHOULD REMAIN GENERALLY WEAK. BEST CHANCE FOR A STRONGER STORM WILL LIKELY EXIST OVER SRN GA/NRN FL...BUT ATTM ANY SEVERE POTENTIAL APPEARS TOO LOW TO WARRANT THE INCLUSION OF A THREAT AREA. ..GOSS/TAYLOR.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 12:46:17 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 08:46:17 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221247 SWODY1 SPC AC 221245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT SUN OCT 22 2006 VALID 221300Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS/FORECAST... BROAD...DEEP CLOSED LOW CENTERED N OF LK SUPERIOR WILL DOMINATE THE ERN TWO THIRDS OF THE NATION THIS PERIOD AS DEAMPLIFYING RIDGE PROGRESSES E INTO SW CANADA AND THE INTERIOR PAC NW. BAND OF FAST W/WSWLY FLOW ON SRN EDGE OF LOW WILL PREVAIL TODAY FROM THE LWR MS/TN VLY TO THE MID AND S ATLANTIC CSTS. AT LOWER LEVELS...ASSOCIATED COLD FRONT WILL CONTINUE SE INTO THE GULF OF MEXICO AND E ACROSS THE APPALACHIANS TOWARD THE ATLANTIC COAST THROUGH THE DAY. BY EARLY MONDAY THE FRONT SHOULD CURVE CYCLONICALLY FROM CAPE COD TO WELL OFF THE MID ATLANTIC COAST...AND THEN SW ACROSS CNTRL FL INTO THE SRN GULF OF MEXICO. FARTHER S... WEAK WARM FRONT NOW OVER THE FL PANHANDLE AND NERN GULF SHOULD CONTINUE TO WEAKEN AS IT LIFTS SLOWLY NE INTO NRN FL AND S GA. SHOWERS AND A FEW THUNDERSTORMS LIKELY WILL PERSIST ALONG AND AHEAD OF COLD FRONT FROM THE N CNTRL GULF E/NE INTO PARTS OF GA AND N FL. ELEVATED STORMS MAY ALSO LINGER FOR SOME TIME TODAY ABOVE FRONTAL SURFACE OVER DEEP S TX. MORE ISOLATED ACTIVITY MAY DEVELOP NWD ALONG THE SC CST...AND IN DPVA/JET EXIT REGION OVER WRN NY/PA. STORMS MAY ALSO FORM OFF THE CAROLINA CST THIS EVENING. LIMITED DEGREE OF INSTABILITY...AND WEAK CONVERGENCE/LARGE SCALE FORCING FOR ASCENT...SUGGEST THAT UPDRAFTS IN MOST AREAS WILL REMAIN FAIRLY WEAK. THE BEST CHANCE FOR STRONGER STORMS SHOULD EXIST OVER SRN GA/NRN FL...AND OVER DEEP S TX....MAINLY BETWEEN NOW AND LATE AFTERNOON. VEERING LOW LEVEL FLOW WITH TIME SHOULD RESULT IN A DIMINISHING THREAT FOR LOW LEVEL STORM ROTATION WITH ANY STRONGER UPDRAFTS IN THE FL PANHANDLE THIS MORNING. ..CORFIDI/TAYLOR.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 16:04:42 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 12:04:42 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221605 SWODY1 SPC AC 221604 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1104 AM CDT SUN OCT 22 2006 VALID 221630Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...DISCUSSION/SYNOPSIS... LONGWAVE UPPER TROUGH WILL REMAIN OVER THE CNTRL/ERN U.S. WITH UPPER LOW CENTER SHIFTING SWD ACROSS WRN ONTARIO INTO THE NRN GREAT LAKES. LEAD UPPER SHORTWAVE TROUGH WILL SHIFT EWD ACROSS THE ERN GREAT LAKES WITH ASSOCIATED SURFACE LOW PRESSURE TROUGH ENHANCING LOW LEVEL CONVERGENCE OVER LAKE ERIE/ONTARIO. GIVEN MINIMAL LAKE INDUCED CONVECTIVE INSTABILITY...AN ISOLATED LIGHTING STRIKE CANNOT BE RULED OUT. TO THE SOUTH...A COLD FRONT WILL BE THE FOCUS FOR SCATTERED STORMS FROM SRN GA/NRN FL INTO SC. ...SRN GA/NRN FL... CONVECTION WILL FOCUS ALONG A WEAK FRONTAL BOUNDARY THAT WILL GRADUALLY SHIFT SWD ACROSS SRN GA/NRN FL. SURFACE HEATING AND WEAK CONVERGENCE WILL ALLOW FOR SCATTERED STORMS TO PERSIST/REDEVELOP ALTHOUGH INSTABILITY WILL REMAIN RELATIVELY WEAK. SHEAR PROFILES SOUTH OF THE COLD FRONT WILL REMAIN MODEST AT BEST WITH MAIN WIND CORE ALOFT WELL NORTH OF THE FRONT. THUS...SEVERE UNLIKELY ALTHOUGH STEEP LOW LEVEL LAPSE RATES MAY ALLOW FOR LOCALLY STRONG WIND GUSTS. ..JEWELL/HALES.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 19:51:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 15:51:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221953 SWODY1 SPC AC 221951 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0251 PM CDT SUN OCT 22 2006 VALID 222000Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SE ATLANTIC COAST AND NRN FL... AS THE PRIMARY UPPER TROUGH SWINGS THROUGH THE GRTLKS REGION...OVERALL DEEP LAYER FLOW REGIME WAS BECOMING WLY ACROSS THE COLD FRONT. POOR LAPSE RATES ALOFT AND INCREASINGLY UNFAVORABLE KINEMATIC REGIME HAVE CONTRIBUTED TO WEAKENING TREND OF THE TSTMS ACCOMPANYING THE FRONT THIS AFTN. THIS TREND SHOULD CONTINUE THIS EVE. FARTHER S...PWAT VALUES ARE LOWER THAN SATURDAY WHERE MINIMAL CONVECTION OCCURRED ALONG THE SEABREEZES. OTHER THAN ISOLD SHOWERS...THE LIGHTNING THREAT ACROSS CNTRL/SRN FL APPEARS MINIMAL /LESS THAN 10 PERCENT PROBABILITY/. ...LWR GRTLKS... CONSIDERABLE CONVECTION ASSOCD WITH AN UPR SHORT WAVE TROUGH AND ATTENDANT COLD FRONT CONTINUES TO ROTATE NEWD ACROSS THE LWR GRTLKS REGION. THERMODYNAMIC PROFILES REMAIN MARGINALLY FAVORABLE FOR ISOLD LIGHTNING STRIKES WITH THE STRONGER CONVECTIVE ELEMENTS. AN ISOLD STRIKE OR TWO COULD ALSO ACCOMPANY ANY LAKE-ENHANCED CONVECTION THAT DEVELOPS LATER TONIGHT. ..RACY.. 10/22/2006  From swody1 at goshenarc.org Mon Oct 23 00:50:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 20:50:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230051 SWODY1 SPC AC 230049 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 PM CDT SUN OCT 22 2006 VALID 230100Z - 231200Z ...NO SVR TSTM AREAS FORECAST... A BROAD UPPER-LEVEL CNTRL AND ERN U.S. TROUGH WILL BE IN PLACE TONIGHT AS A COLD FRONT MOVES SEWD ACROSS FL AND THE ERN SEABOARD. MOISTURE...INSTABILITY AND CONVERGENCE APPEAR SUFFICIENT FOR THUNDERSTORM ACTIVITY ALONG THE BOUNDARY IN SRN GA AND NRN FL. HOWEVER...WEAK LARGE-SCALE ASCENT SHOULD KEEP THE ACTIVITY VERY ISOLATED THIS EVENING. ELSEWHERE...A FEW WEAK THUNDERSTORMS SHOULD CONTINUE FOR 1 TO 2 MORE HOURS IN ERN PA ASSOCIATED WITH STRONG LIFT FROM BANDS OF ASCENT AHEAD OF THE UPPER-TROUGH. ISOLATED THUNDERSTORMS MAY ALSO OCCUR OVER THE WARM WATERS OF LAKE ERIE AND ONTARIO THIS EVENING. ..BROYLES.. 10/23/2006  From swody1 at goshenarc.org Wed Oct 25 05:11:51 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 25 Oct 2006 01:11:51 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250515 SWODY1 SPC AC 250514 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1214 AM CDT WED OCT 25 2006 VALID 251200Z - 261200Z ...NO SVR TSTM AREAS FORECAST... ...SRN AND CNTRL PLAINS... A NRN ROCKIES UPPER-LEVEL TROUGH WILL DIG SEWD AND CLOSE-OFF OVER THE FOUR CORNERS REGION TODAY. IN RESPONSE...A SFC LOW WILL DEEPEN OVER SE CO AS MOISTURE ADVECTION INCREASES IN THE SRN AND CNTRL PLAINS QUICKLY TRANSPORTING LOWER 60 F SFC DEWPOINTS NWD ACROSS NORTH TX AND WRN OK BY LATE THIS AFTERNOON. THUNDERSTORM DEVELOPMENT MAY OCCUR ALONG A STRONGLY CONVERGENT WARM FRONT EXTENDING EWD FROM THE SFC LOW ACROSS KS INTO NRN MO. FORECAST SOUNDINGS ALONG THE WARM FRONT THIS AFTERNOON SHOW STRONG VERTICAL SHEAR AND RELATIVELY COLD TEMPS ALOFT SUGGESTING HAIL WILL BE POSSIBLE WITH THE BETTER ORGANIZED CELLS. IF A MARGINAL SEVERE THREAT DEVELOPS IN KS...THE THREAT WOULD LIKELY BE CONFINED TO THE LATE AFTERNOON WHEN INSTABILITY WILL BE MAXIMIZED ACROSS THE REGION. FURTHER SOUTH...THUNDERSTORMS MAY ALSO DEVELOP ACROSS OK...EAST TX AND IN THE TX COASTAL PLAINS DUE TO LIFT ASSOCIATED WITH A 50 TO 60 KT LOW-LEVEL JET. THE STRONG LOW-LEVEL FLOW AND VEERING LOW-LEVEL WINDS WITH HEIGHT MAY BE FAVORABLE FOR A FEW ROTATING THUNDERSTORMS CAPABLE OF STRONG WIND GUSTS MAINLY NEAR PEAK HEATING LATE THIS AFTERNOON. ..BROYLES/GRAMS.. 10/25/2006  From swody1 at goshenarc.org Wed Oct 25 11:59:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 25 Oct 2006 07:59:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251200 SWODY1 SPC AC 251158 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0658 AM CDT WED OCT 25 2006 VALID 251300Z - 261200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... MID/UPPER LVL SHORT WAVE TROUGH IS MOVING EWD OVER THE 4-CORNERS THIS MORNING JUST AHEAD OF MORE LATITUDINAL TROUGH MOVING SEWD OVER THE NRN PLATEAU. MOISTURE PLUME FROM TROPICAL STORM PAUL IS EVIDENT THROUGH WATER VAPOR IMAGERY STRETCHING FROM THE LOCATION OF TROPICAL STORM PAUL OVER THE SRN TIP OF THE BAJA PENINSULA NEWD INTO THE SRN PLAINS. MID/UPPER LEVEL TROUGH MOVING SEWD THRU THE NRN PLATEAU IS EXPECTED TO INTENSIFY TODAY AS IT MOVES INTO THE 4-CORNERS AREA EJECTING WEAKER TROUGH JUST AHEAD OF IT INTO THE CENTRAL PLAINS. CONSIDERABLE CLOUD COVER OVER THE PLAINS SHOULD CONTINUE MUCH OF THE DAY LIMITING POTENTIAL INSTABILITY AND SEVERE STORM POTENTIAL. ...PARTS OF SRN KS/NRN OK INTO ERN TX... AS MID/UPPER LEVEL LOW DIGS INTO THE SWRN PORTIONS OF THE SWRN U.S. THIS AFTERNOON AND TONIGHT...STRONG UPPER LEVEL JET BETWEEN 130-160 KT WILL EXTEND FROM SRN AZ ENEWD INTO THE LOWER OH VALLEY. THIS WILL BE ACCOMPANIED BY 500 MB WINDS OF 80-90 KT TURNING AROUND THE BASE OF THE TROUGH FROM ERN NV INTO W TX. THE EXIT REGION OF THIS JET WILL BE COUPLING WITH WRN AREAS OF THE LOW LEVEL JET BY THE END OF THE PERIOD AS LOW LEVEL WINDS OF 40-50 KT EXTEND FROM THE CENTRAL PARTS OF THE TX GULF COAST INTO S CENTRAL MO. THIS IS WHEN THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE ACROSS THE PLAINS AS VERTICAL SHEAR INCREASES TONIGHT. AGAIN CONSIDERABLE CLOUDINESS IS EXPECTED TO INHIBIT POTENTIAL INSTABILITY AND SEVERE WEATHER POTENTIAL DURING THE PERIOD. ..MCCARTHY/GRAMS.. 10/25/2006  From swody1 at goshenarc.org Thu Oct 26 05:59:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 01:59:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260603 SWODY1 SPC AC 260601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT THU OCT 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF ERN TX/OK INTO THE LOWER MS VALLEY... ...SYNOPSIS... LEAD IMPULSE NOW OVER THE MID MS VALLEY WILL CONTINUE TO DEAMPLIFY AS IT MOVES THROUGH SHORTWAVE RIDGE AND INTO CONFLUENT FLOW REGIME OVER THE OH VALLEY AREA. IN ITS WAKE...A MUCH STRONGER SHORTWAVE TROUGH WILL MOVE ESEWD INTO THE SRN PLAINS THURSDAY AFTERNOON AND EVENING...THEN INTO THE LOWER MS VALLEY THURSDAY NIGHT. LEE CYCLOGENESIS WILL ACCOMPANY THIS FEATURE. THE DRYLINE WILL SHARPEN FROM WRN OK THROUGH WRN TX EARLY THURSDAY AS THE LOW DEVELOPS OVER WRN OK. THIS BOUNDARY WILL SHIFT EWD DURING THE DAY AS THE PACIFIC FRONT MERGES WITH IT. A WARM FRONT WILL DEVELOP AND EXTEND EWD FROM THE LOW ACROSS NRN OK. AS THE LOW SHIFTS EWD INTO THE LOWER MS VALLEY DURING THE EVENING...THE SLY LOW LEVEL JET WILL STRENGTHEN ACROSS PARTS OF LA AND MS. THIS WILL CONTRIBUTE TO A MARINE BOUNDARY LIFTING INLAND ALONG THE LA AND MS COASTS THURSDAY EVENING. ...SRN PLAINS THROUGH LOWER MS VALLEY AREA... PARTIALLY MODIFIED GULF AIR WITH BOUNDARY LAYER DEWPOINTS IN THE LOW TO MID 60S HAS ALREADY ADVECTED AS FAR N AS CNTRL OK WITH UPPER 60S ACROSS N CNTRL TX. PLUME OF DEEPER MOISTURE IS EXPECTED TO PERSIST ACROSS TX INTO PARTS OF THE LOWER MS VALLEY ALONG WARM CONVEYOR BELT WITH MOISTURE AUGMENTED BY REMNANTS OF PAUL. A RELATIVELY NARROW AXIS OF INSTABILITY MAY DEVELOP THURSDAY AFTERNOON W OF DEEPER MOIST PLUME FROM THE ERN HALF OF OK SWD THROUGH CNTRL AND ERN TX. HERE...MODEST 6.5 C/KM MID LEVEL LAPSE RATES WILL OVERSPREAD THE LOW LEVEL MOIST AXIS AND POTENTIAL FOR SURFACE HEATING WILL EXIST AS LOW CLOUDS MIX OUT IN DRY SLOT REGION. MLCAPE FROM 1000 TO 1500 J/KG WILL BE POSSIBLE. PRIMARY LOW LEVEL JET WILL SHIFT EWD THROUGH THE LOWER MS VALLEY AND SERN U.S. IN ASSOCIATION WITH DEAMPLIFYING LEAD IMPULSE. HOWEVER...SOME INCREASE AND BACKING OF THE LOW LEVEL FLOW SHOULD OCCUR FROM ERN OK INTO NERN TX AS THE LOW CONSOLIDATES OVER OK. THIS ALONG WITH APPROACHING 90+ KT MID LEVEL JET WILL RESULT IN FAVORABLE SHEAR PROFILES FOR SUPERCELLS. STRONGEST 0-1 KM SHEAR FOR LOW LEVEL MESOCYCLONES AND POSSIBLE TORNADOES DURING THE AFTERNOON IS EXPECTED JUST E OF SURFACE LOW AND NEAR WARM FRONT OVER NRN AND ERN OK OR SRN KS. STORMS ARE EXPECTED TO REDEVELOP OVER NRN OK/SRN KS DURING THE AFTERNOON AS WELL AS ALONG AND E OF DRYLINE/PACIFIC FRONT AS FORCING FOR ASCENT ATTENDING THE SHORTWAVE TROUGH INCREASES. VERTICAL SHEAR PROFILES WILL BE SUFFICIENT FOR SUPERCELLS WITH LARGE HAIL AND ISOLATED TORNADOES POSSIBLE. OTHER STORMS MAY DEVELOP FARTHER S ACROSS TX ALONG AND E OF PACIFIC FRONT. LOW LEVEL SHEAR PROFILES IN THIS REGION WILL NOT BE A STRONG AS FARTHER N...BUT DEEP LAYER SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS. SOME STORMS MAY EVENTUALLY EVOLVE INTO LINE SEGMENTS WITH EMBEDDED SUPERCELLS AS THEY CONTINUE EWD INTO ERN TX DURING THE EVENING WITH A CONTINUING THREAT OF MAINLY DAMAGING WIND. SOME WEAKENING IS EXPECTED AS ACTIVITY MOVES TOWARD THE LESS UNSTABLE REGIME OVER AR OVERNIGHT. OTHER ACTIVITY WILL CONTINUE WITHIN THE PLUME OF DEEPER MOISTURE FROM SERN TX INTO THE LOWER MS VALLEY. LAPSE RATES WILL REMAIN WEAK IN THIS REGION. HOWEVER...RICHER LOW LEVEL MOISTURE ACCOMPANYING THE MARINE FRONT WILL ADVECT NWD INTO SRN LA/MS DURING THE EVENING. POTENTIAL WILL EXIST FOR SUPERCELLS AND ISOLATED TORNADOES...MAINLY OVERNIGHT FROM PARTS SERN TX INTO LA AND SRN MS AS THE LOW LEVEL JET STRENGTHENS...RESULTING IN FAVORABLE LOW LEVEL HODOGRAPHS. ..DIAL.. 10/26/2006  From swody1 at goshenarc.org Thu Oct 26 12:09:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 08:09:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261210 SWODY1 SPC AC 261209 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0709 AM CDT THU OCT 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE S CENTRAL U.S. INTO AR/LA.... ...SYNOPSIS... STRONG MID/UPPER LEVEL LOW CURRENTLY OVER THE SRN UT/CO BORDER WILL MOVE EWD OVER THE NWRN TX PANHANDLE BY LATER THIS AFTERNOON INTO NERN OK BY THE END OF THE PERIOD. SURFACE LOW CONTINUES TO DEEPEN OVER SERN CO AT THIS TIME AND WILL BE OVER NWRN OK BY 21Z INTO SWRN MO/NWRN AR BY FRI MORNING. A DRYLINE EXTENDS FROM JUST SW OF ICT THIS MORNING SWWD JUST W OF MAF WITH A WARM FRONTAL BOUNDARY FROM S CENTRAL KS SEWD THROUGH SERN OK INTO SERN LA. ALSO...A COLD FRONT EXTENDS FROM THE SERN CO LOW SWD AND SWWD THROUGH SERN AND S CENTRAL NM AND W CENTRAL AZ. THIS FRONTAL SYSTEM WILL MOVE EWD AS WELL THROUGH TONIGHT ENHANCING UPWARD ASCENT AND THUNDERSTORMS ACROSS PARTS OF KS...CENTRAL AND ERN OK AND TX INTO PARTS OF MO AND AR AND THE LOWER MS VALLEY DURING THE PERIOD. ...SERN KS/NERN OK INTO SWRN MO/NWRN AR... VERY STRONG RIBBON OF UPPER LEVEL WINDS OF 130-150 KT WILL EXTEND FROM CENTRAL AZ INTO CENTRAL OK AND NRN TX THROUGH THIS EVENING...THEN INTO SRN MO/NRN AR BY FRIDAY MORNING. CLOSE ANALYSIS OF THESE WINDS SHOW THAT THE NRN BRANCH OF THIS JET WILL BE FROM SERN AZ INTO SERN KS BY THIS AFTERNOON...WHILE THE SRN BRANCH EXTENDS FROM THE BAJA SPUR INTO CENTRAL TX. THUS...THERE WILL BE SOME UPPER LEVEL DIVERGENCE FROM CENTRAL OK SWD INTO CENTRAL TX TO ENHANCE UPWARD ASCENT ASSOCIATED WITH COLD FRONT/DRYLINE COMBINATION DURING THE AFTERNOON INTO TONIGHT. WINDS AT 500 MB REFLECT THIS STRUCTURE AS WELL WITH A 100 KT JET STREAK FROM SERN NM NEWD INTO S CENTRAL KS FOR THE NRN BRANCH AS THE SRN BRANCH OF 60-80 KT EXTENDS FROM THE TX BIG BEND INTO NERN TX. LOW LEVEL JET AXIS IS ANALYZED FARTHER E OUT AHEAD OF THE APPROACHING SYSTEM AS 40-50 KT WINDS ARE FORECAST FROM SWRN LA INTO WRN KY BY LATER THIS AFTERNOON. BUT...STRONG WLY FLOW AT LOW LEVELS INCREASE TONIGHT WHICH WILL AID IN LOW LEVEL FRONTAL FORCING ACROSS ERN KS INTO ERN TX. THIS TYPE OF KINEMATIC STRUCTURE LOOKS TO SET UP MORE OF A BIMODAL TYPE SITUATION OVER THE PLAINS LATER TODAY. MODELS INDICATE THAT MID LEVEL LAPSE RATES OVER SERN KS INTO THE NERN QUARTER OF OK WILL BE AROUND 7 C/KM WITH MLCAPE VALUES OF 1200-1600 J/KG THIS EVENING...AND DEEP LAYER SHEAR OF 50-70 KT. THUS...THIS AREA WILL BE ONE AREA TO CONSIDER FOR HAIL AND DAMAGING WINDS AS THE FRONTAL BOUNDARY/ASSOCIATED SQUALL LINE DEVELOPS ALONG/JUST AHEAD OF THE FRONT. ISOLATED TORNADOES WOULD ALSO NEED TO BE CONSIDERED ACROSS THIS AREA WITH THAT MUCH DEEP LAYER SHEAR AND WITH LCL/LFC LEVELS BEING AT/JUST BELOW 850 MB. ...SERN OK INTO NERN AND E CENTRAL TX... THIS WILL BE THE SECOND AREA IN THIS SITUATION AS THE SUBTLE SRN STREAM EXTENDS EWD ACROSS THIS REGION LATE THIS AFTERNOON AND EARLY TONIGHT. THERE COULD BE A FEW DISCRETE SUPERCELLS DEVELOP AHEAD OF THE COLD FRONT OVER PARTS OF SERN OK INTO NERN AND E CENTRAL TX WHERE FORECAST SOUNDINGS SHOW A BIT MORE INSTABILITY WITH MLCAPE NEAR 2000 J/KG AND CLOSER LCL/LFC LEVELS JUST BELOW 850 MB. THIS AREA WILL ALSO BE IN A MORE FAVORABLE EXIT REGION OF THE UPPER LEVEL JET STREAK TO ENHANCE ASCENT WITH DEEP LAYER SHEAR INCREASING TO AROUND 50 KT BY EARLY TONIGHT. AGAIN LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN THREATS...BUT A FEW TORNADOES COULD OCCUR LATER THIS AFTERNOON/EARLY TONIGHT WHERE THERE IS BETTER COUPLING OF LOW/MID LEVEL WINDS. MAIN THREAT OF DAMAGING WINDS WILL BECOME MORE LIKELY AFTER EARLY THIS EVENING AS MAIN VORTEX MOVES THROUGH OK AND THERE IS AN INCREASE IN WLY LOW LEVEL FLOW BEHIND THE MAIN FRONTAL PUSH THAT MOVES INTO SWRN MO INTO CENTRAL AR LATER TONIGHT. ..MCCARTHY/GRAMS.. 10/26/2006  From swody1 at goshenarc.org Thu Oct 26 19:53:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 15:53:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261956 SWODY1 SPC AC 261955 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0255 PM CDT THU OCT 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN OK/WRN AR SWD INTO E TX/LA/SWRN MS... ...SERN TX ACROSS SRN LA... STORMS ARE ONGOING ATTM ACROSS SERN TX AND INTO SWRN LA...WITHIN VERY MOIST BOUNDARY LAYER AIRMASS. LATEST VWPS AND 18Z LAKE CHARLES RAOB INDICATE SUFFICIENT SHEAR IN THE LOWEST 1 TO 2 KM FOR LOW-LEVEL MESOCYCLONE DEVELOPMENT -- THUS SUPPORTING A CONTINUED THREAT FOR A COUPLE OF TORNADOES. OTHERWISE...SEVERE THREAT APPEARS LIMITED INVOF THE TX/LA GULF COAST DUE TO VERY MOIST/MINIMALLY-UNSTABLE ENVIRONMENT. ADDITIONAL CONVECTIVE DEVELOPMENT IS EXPECTED ACROSS E TX THIS EVENING -- W AND NW OF ONGOING COASTAL STORMS -- AS FRONT APPROACHES FROM THE W AHEAD OF UPPER LOW/TROUGH. ALONG WITH POTENTIAL FOR AN ISOLATED TORNADO...LOCALLY-DAMAGING WINDS MAY ALSO OCCUR -- PARTICULARLY IF STORMS ORGANIZE LINEARLY ALONG/AHEAD OF FRONT. STORMS WILL CONTINUE/SHIFT EWD ACROSS THE SABINE RIVER OVERNIGHT...WITH AT LEAST A LOW-END SEVERE THREAT LINGERING THROUGH THE END OF THE PERIOD. ...NERN TX INTO WRN AR/NRN AND ERN OK... STRONG UPPER LOW NOW MOVING INTO THE WRN OK/NWRN TX PANHANDLES WILL CONTINUE EWD ACROSS OK THROUGH THE REMAINDER OF THE PERIOD. ASSOCIATED SURFACE LOW -- NOW S OF DODGE CITY KS -- WILL LIKEWISE SHIFT EWD...REACHING AR LATE IN THE PERIOD. BOUNDARY-LAYER AIRMASS ACROSS ERN OK/NERN TX CONTINUES TO MOISTEN AHEAD OF THE APPROACHING FEATURE...WHICH COMBINED WITH DAYTIME HEATING IS RESULTING IN MARGINAL DESTABILIZATION. THIS TREND SHOULD CONTINUE ACROSS ERN OK AND INTO WRN AR/NERN TX/NWRN LA INTO EARLY EVENING...AS COOLING ALOFT ASSOCIATED WITH THE UPPER LOW SPREADS EWD ACROSS MOISTENING BOUNDARY LAYER. ATTM...IT APPEARS THAT SCATTERED STORMS SHOULD BEGIN TO DEVELOP BY LATE THIS AFTERNOON/EARLY THIS EVENING INVOF A CONSOLIDATING WARM FRONT OVER N CENTRAL/NERN OK/SERN KS...WHILE SCATTERED TO ISOLATED STORMS ALSO DEVELOP SWD ALONG COLD FRONT ACROSS THE ERN HALF OF OK. DEEP-LAYER WIND FIELD WILL REMAIN FAVORABLE FOR SUPERCELLS...SO AT LEAST ISOLATED SEVERE STORMS ARE ANTICIPATED. ALONG WITH THE POTENTIAL FOR HAIL...LOCALLY-DAMAGING WINDS WILL BE POSSIBLE GIVEN STRENGTH OF WIND FIELD. GREATEST THREAT APPEARS TO EXIST OVER THE ARKLATEX...WHERE MOST FAVORABLE INSTABILITY/SHEAR COMBINATION IS EXPECTED TONIGHT. A BRIEF TORNADO OR TWO WILL ALSO BE POSSIBLE -- PARTICULARLY IN BACKED SURFACE FLOW NEAR/N OF WARM FRONT. STORMS/SEVERE THREAT WILL PERSIST/SHIFT EWD THROUGH THE PERIOD. ..GOSS.. 10/26/2006  From swody1 at goshenarc.org Fri Oct 27 00:56:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 20:56:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270100 SWODY1 SPC AC 270058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT THU OCT 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF SERN KS...ERN OK...ERN TX INTO THE LOWER MS VALLEY... ...SRN KS THROUGH ERN OK AND NERN TX... SURFACE ANALYSIS SHOWS A PACIFIC FRONT EXTENDING FROM A SURFACE LOW IN N CNTRL OK SSWWD THROUGH N CNTRL AND SWRN TX ALONG WITH AN E-W BOUNDARY ACROSS EXTREME NRN OK. A PRE-FRONTAL TROUGH EXTENDS FROM N CNTRL TX NWD INTO SERN OK. A WARM FRONT SEPARATING RICHER LOW LEVEL GULF MOISTURE FROM MODIFIED CP AIR EXTENDS FROM LA NWWD INTO NERN TX. THE SURFACE LOW WILL MOVE EWD THROUGH NRN OK OVERNIGHT WITHIN ZONE OF ASCENT ASSOCIATED WITH EWD ADVANCING SHORTWAVE TROUGH AND ITS ATTENDANT UPPER JET. TORNADIC STORMS THAT DEVELOPED EARLIER THIS EVENING ACROSS SWRN KS ALONG THE E-W BOUNDARY HAVE WEAKENED. OTHER STORMS ARE DEVELOPING FARTHER E ALONG/N OF THIS BOUNDARY ACROSS SERN KS. SOME POTENTIAL FOR AN ISOLATED TORNADO MAY EXIST NEXT COUPLE HOURS AS STORMS DEVELOP ON THIS BOUNDARY. HOWEVER...SWLY ORIENTATION OF THE STEERING FLOW RELATIVE TO THE SLIGHT SWD MOTION OF THE BOUNDARY HAS RESULTED IN STORMS BEING UNDERCUT AND BECOMING ELEVATED AS THEY CROSS ONTO THE COOL SIDE. THUS PRIMARY THREAT APPEARS TO BE TRANSITIONING TO HAIL...BUT EVEN THE HAIL THREAT IS SOMEWHAT LIMITED BY MODEST INSTABILITY. SOME POTENTIAL STILL EXISTS FOR OTHER STORMS TO DEVELOP ACROSS ERN OK. THE NEAR SURFACE FLOW IS STILL BACKED TO SELY IN THIS REGION E OF THE SURFACE LOW. WITH PRIMARY LOW LEVEL JET EXPECTED TO REMAIN SE OF THIS AREA...LOW LEVEL HODOGRAPHS WILL NOT BE PARTICULARLY LARGE. HOWEVER...SUFFICIENT VEERING...LOW LEVEL AND DEEP LAYER SHEAR EXIST FOR A THREAT OF SUPERCELLS WITH HAIL AND LOW LEVEL MESOCYCLONES...BUT CONDITIONAL UPON THE INITIATION OF SURFACE BASED STORMS. THE INSTABILITY AXIS IN THIS REGION IS NARROW...AND AS THE BOUNDARY LAYER CONTINUES TO COOL IT APPEARS MANY OF THE STORMS MAY BE INITIATED WITHIN WEAK WARM ADVECTION REGIME ABOVE THE COOLER BOUNDARY LAYER ACROSS EXTREME ERN OK INTO AR. FARTHER S ACROSS NERN TX...OTHER STORMS ARE DEVELOPING WITHIN ZONE OF ASCENT ALONG AND JUST E OF PRE-FRONTAL TROUGH WHERE THE ATMOSPHERE REMAINS MODERATELY UNSTABLE WITH MLCAPE FROM 1000 TO 1500 J/KG. LOW LEVEL SHEAR IS WEAKER IN THIS REGION THAN FARTHER NORTH. HOWEVER...EFFECTIVE SHEAR IN EXCESS OF 50 KT IS MORE THAN SUFFICIENT FOR SUPERCELLS. SOME STORMS MAY ALSO EVOLVE INTO BOWING SEGMENTS. PRIMARY THREAT APPEARS TO BE DAMAGING WIND...THOUGH SOME HAIL IS POSSIBLE WITH THE STRONGER STORMS. OVERALL HAIL THREAT IS SOMEWHAT LIMITED BY WEAK MID LEVEL LAPSE RATES. ...SERN TX THROUGH LA AND SRN MS... STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN PLUME OF DEEP MOISTURE FROM SERN TX INTO LA AND SRN MS OVERNIGHT. SWLY LOW LEVEL JET IS FORECAST TO STRENGTHEN TO IN EXCESS OF 50 KT FROM SERN TX INTO THE LOWER MS VALLEY. THIS WILL HELP TO ADVECT BOUNDARY LAYER DEWPOINTS NEAR 70 FARTHER INLAND ACROSS LA IN WAKE OF RETREATING WARM FRONT. THE INCREASING LOW LEVEL JET WILL RESULT IN FAVORABLE 0-1 KM HODOGRAPHS FOR A THREAT OF ISOLATED TORNADOES GIVEN INLAND ADVECTION OF RICHER LOW LEVEL MOISTURE AS STORMS TRAIN FROM SW-NE ALONG WARM CONVEYOR BELT. PRIMARY LIMITING FACTOR ARE THE WEAK LAPSE RATES AND MARGINAL INSTABILITY. ..DIAL.. 10/27/2006  From swody1 at goshenarc.org Fri Oct 27 05:18:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 27 Oct 2006 01:18:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270521 SWODY1 SPC AC 270520 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1220 AM CDT FRI OCT 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CNTRL AND ERN GULF COASTAL AREA INTO PARTS OF NWRN FL... ...SYNOPSIS... POSITIVELY TILTED SHORTWAVE TROUGH PRESENTLY OVER OK WILL MOVE ESEWD THROUGH THE LOWER MS VALLEY AND SERN STATES FRIDAY...REACHING THE CAROLINAS LATE FRIDAY NIGHT. SURFACE LOW AND COLD FRONT WILL ATTEND THIS FEATURE. THE LOW SHOULD BE OVER THE WRN TN VALLEY WITH A COLD FRONT EXTENDING SWD THROUGH THE LOWER MS VALLEY AT THE START OF THIS PERIOD. THE LOW WILL SHIFT ENEWD INTO ERN KY WITH TRAILING FRONT THROUGH ERN TN...WRN GA AND INTO THE ERN GULF EARLY FRIDAY EVENING. BY THE END OF THIS PERIOD...THIS BOUNDARY SHOULD EXTEND FROM EXTREME ERN VA/NC SWWD THROUGH NRN FL. ...CNTRL AND ERN GULF COASTAL AREA THROUGH NWRN FL... HEIGHT FALLS ACCOMPANYING THE UPPER TROUGH WILL CONTRIBUTE TO A STRONG SWLY 60+ KT LOW LEVEL JET THAT WILL SHIFT EWD THROUGH THE SERN STATES DURING THE DAY AS SURFACE LOW ADVANCES THROUGH THE TN VALLEY. THIS SHOULD RESULT IN ADVECTION OF NEAR 70 DEWPOINTS INTO SRN PORTIONS OF GULF COASTAL STATES. HOWEVER...NWD RECOVERY OF AIRMASS WILL BE LIMITED BY WIDESPREAD RAIN EXPECTED WITHIN PLUME OF DEEPER MOISTURE ALONG WARM CONVEYOR BELT OVER THE SERN STATES. NEAR THE COAST WHERE RICHER MOISTURE ADVECTS INLAND...MLCAPE FROM 500 TO 1000 J/KG WILL BE POSSIBLE WITHIN THE MOIST...WEAK LAPSE RATE ENVIRONMENT. STORMS WILL LIKELY CONTINUE DEVELOPING IN ZONE OF ASCENT WITHIN THE PRE-FRONTAL WARM SECTOR AND SHIFT EWD THROUGH THE SERN STATES DURING THE DAY. STRONGER STORMS ARE EXPECTED JUST INLAND OF THE COAST FROM SERN LA THROUGH SRN AL...SWRN GA AND THE FL PANHANDLE WHERE INFLOW FROM HIGHER THETA-E AIR WILL EXIST. THE INTENSIFYING LOW LEVEL JET WILL RESULT IN LARGE LOW LEVEL HODOGRAPHS. THIS ALONG WITH STRONG SHEAR THROUGH A DEEPER LAYER WILL BE SUPPORTIVE OF ORGANIZED STORM STRUCTURES INCLUDING BOW ECHOES AND SUPERCELLS CAPABLE OF PRODUCING DAMAGING WIND AND ISOLATED TORNADOES. OVERALL THREAT MAY BE TEMPERED SOMEWHAT BY THE MARGINAL THERMODYNAMIC ENVIRONMENT. ...COASTAL CAROLINAS... NEAR SURFACE TRAJECTORIES WILL EMANATE FROM CP HIGH PRESSURE OFF THE ATLANTIC SEABOARD IN THIS REGION UNTIL FRIDAY AFTERNOON AND EVENING WHEN THE FLOW SHOULD VEER TO SLY IN ADVANCE OF SURFACE LOW. THIS WILL ALLOW MODIFYING BOUNDARY LAYER AIR WITH DEWPOINTS IN THE 60S TO ADVECT NWD TOWARD THE COASTAL CAROLINAS OVERNIGHT. THE RICHER MOISTURE WILL LIKELY RESIDE S OF A COASTAL BOUNDARY THAT COULD MOVE INLAND LATER FRIDAY NIGHT. LOW LEVEL AND MID LEVEL WIND FIELDS WILL STRENGTHEN SIGNIFICANTLY AS THE UPPER TROUGH AND ATTENDANT LOW LEVEL JET MOVE TOWARD THE CAROLINAS. WITH RAIN EXPECTED TO SPREAD EWD INTO THE COOL AIRMASS ALREADY IN PLACE OVER THE CAROLINAS BY EARLY FRIDAY...INLAND RECOVERY WILL BE DIFFICULT EXCEPT POSSIBLY NEAR THE COASTAL AREAS. THE THREAT FOR ISOLATED TORNADOES OR DAMAGING WIND MAY INCREASE IN VICINITY OF THE COASTAL BOUNDARY FRIDAY NIGHT AS SHEAR PROFILES INCREASE AND HIGHER THETA-E AIR ADVECTS INLAND. HOWEVER...GIVEN THE POTENTIAL LIMITING FACTORS UPON THE THERMODYNAMIC ENVIRONMENT...LOW SEVERE PROBABILITIES WILL BE MAINTAINED AT THIS TIME. AN UPGRADE TO SLIGHT RISK MIGHT BE NECESSARY IN LATER OUTLOOKS IF IT BEGINS TO APPEAR MORE INSTABILITY WILL DEVELOP THAN CURRENTLY ANTICIPATED. ..DIAL/GRAMS.. 10/27/2006  From swody1 at goshenarc.org Fri Oct 27 12:25:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 27 Oct 2006 08:25:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271228 SWODY1 SPC AC 271226 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0726 AM CDT FRI OCT 27 2006 VALID 271300Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL GULF COAST STATES INTO FL... POWERFUL UPPER LOW CURRENTLY OVER OK WILL TRACK EASTWARD INTO WESTERN TN BY 00Z...THEN ACCELERATE RAPIDLY NORTHEASTWARD INTO THE CENTRAL APPALACHIANS BY 28/12Z. RELATIVELY DEEP SURFACE LOW WILL TRACK ALONG SIMILAR PATH THROUGH THE PERIOD AS TRAILING COLD FRONT SWEEPS ACROSS THE SOUTHEAST STATES. THIS FRONT WILL BE THE PRIMARY FOCUS FOR STRONG/SEVERE THUNDERSTORMS TODAY. ...LA/MS/AL THIS MORNING... INTENSE THUNDERSTORMS ARE ONGOING THIS MORNING OVER SOUTHEAST LA/SOUTHERN MS. THESE STORMS ARE IN PRE-FRONTAL WARM SECTOR CHARACTERIZED BY DEWPOINTS IN THE UPPER 60S/LOWER 70S AND MUCAPE OF 500-1000 J/KG. LOCAL VAD DATA IN THIS REGION SHOWS VERY STRONG LOW LEVEL AND DEEP LAYER VERTICAL SHEAR /3KM SR-HELICITY OF 300-500 M2/S2 AND 6KM SHEAR OF 50-65 KNOTS/. STRENGTH OF SHEAR AND INCREASING FORCING FOR ASCENT WILL PROMOTE CONTINUED SUPERCELL POTENTIAL THROUGH THE MORNING AND EARLY AFTERNOON. WEAK LAPSE RATES AND MINIMAL CAPE WILL LESSEN THE HAIL THREAT. HOWEVER...DAMAGING WINDS AND TORNADOES WILL BE POSSIBLE IN STRONGER CELLS. ...GA/FL THIS AFTERNOON AND TONIGHT... VERY STRONG SOUTHERLY LOW LEVEL JET WILL BE MAINTAINED THROUGH THE AFTERNOON AND EVENING AS LINE OF STORMS PROGRESSES EASTWARD INTO PARTS OF GA/FL. EXTENT OF DAYTIME HEATING IS UNCERTAIN OVER THIS REGION...LIMITING CONFIDENCE IN MORE ORGANIZED SEVERE THREAT. NEVERTHELESS...WITH 60-70 KNOT LOW LEVEL WINDS AND APPROACHING SQUALL LINE...POTENTIAL WILL EXIST FOR DAMAGING WINDS AND ISOLATED TORNADOES IN STRONGEST OF CELLS. ...CAROLINAS OVERNIGHT... FINALLY...MODELS AGREE ON LOW LEVEL MOISTENING/DESTABILIZATION ACROSS THE CAROLINAS OVERNIGHT TONIGHT AS UPPER SYSTEM APPROACHES AND LOW LEVEL WINDS STRENGTHEN. DESPITE VERY STRONG WIND FIELDS...WILL MAINTAIN ONLY LOW SEVERE PROBABILITIES AT THIS TIME DUE TO FORECAST OF WEAK LAPSE RATES AND LACK OF CONFIDENCE IN RICH ATLANTIC MOISTURE PLUME. HOWEVER...THIS AREA WILL BE MONITORED IN LATER UPDATES FOR THE POTENTIAL OF GREATER DESTABILIZATION AND POSSIBLE OUTLOOK UPGRADE TO SLIGHT RISK. ..HART/GRAMS.. 10/27/2006  From swody1 at goshenarc.org Sun Oct 29 15:51:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 10:51:21 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291554 SWODY1 SPC AC 291552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0952 AM CST SUN OCT 29 2006 VALID 291630Z - 301200Z ...NO SVR TSTM AREAS FORECAST... ...NORTHEAST... A DEEP UPPER LOW OVER QUEBEC WILL SLOWLY MOVE NEWD TODAY. LIFT AHEAD OF THE UPPER TROUGH AXIS ALONG WITH STEEP LAPSE RATES WILL SUPPORT ISOLATED TSTMS OVER PORTIONS OF ERN/NRN ME THROUGH MID AFTERNOON. ADDITIONALLY...UNIDIRECTIONAL WLY FLOW ALONG WITH STEEP LOW LEVEL LAPSE RATES ABOVE WARM WATERS OF LAKE ONTARIO WILL CONTINUE TO SUPPORT A LAKE EFFECT RAIN/SNOW BAND EXTENDING INTO NWRN UPSTATE NY. SUFFICIENT INSTABILITY GIVEN THE WARM LAKE TEMPERATURES AND COLD MID LEVEL TEMPERATURES WILL SUPPORT ISOLATED TSTMS IN THIS AREA AS WELL. ...WRN MT... A STRONG UPPER TROUGH WILL MOVE SEWD FROM SRN BRITISH COLUMBIA THIS MORNING THROUGH THE NRN ROCKIES TONIGHT. AHEAD OF THIS TROUGH...A COLD FRONT WILL PUSH SWD ACROSS MT. MODERATE UPSLOPE FLOW ALONG THE NRN ROCKIES FRONT RANGE IN THE WAKE OF A COLD FRONT ALONG WITH MID LEVEL FRONTOGENETIC FORCING AND STEEP MID LEVEL LAPSE RATES MAY SUPPORT A FEW LIGHTNING STRIKES LATE THIS AFTERNOON AND OVERNIGHT. ...SRN AZ/SWRN NM... A BROAD FETCH OF MID/HIGH LEVEL PACIFIC MOISTURE WILL STREAM ACROSS THE REGION THROUGH TONIGHT AHEAD OF AN UPPER TROUGH LOCATED OFF THE SRN CA/BAJA CA COAST THIS MORNING. 12Z OBSERVED SOUNDINGS AT TUCSON AND GUAYMAS /SONORA MX/ BOTH INDICATED STEEP LAPSE RATES IN THE RELATIVELY MOIST 500-400 MB LAYER. SUFFICIENT LIFT AHEAD OF THE UPPER TROUGH MAY SUPPORT AN ISOLATED LIGHTNING STRIKE IF MOISTENING CAN OCCUR JUST BELOW THIS LAYER. COVERAGE OF THUNDERSTORMS WILL BE INSUFFICIENT TO WARRANT A CONTOURED AREA. ..CROSBIE/EVANS.. 10/29/2006  From swody1 at goshenarc.org Sun Oct 29 19:11:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 14:11:53 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291912 SWODY1 SPC AC 291910 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0110 PM CST SUN OCT 29 2006 VALID 292000Z - 301200Z ...NO TSTM AREAS FORECAST... ...SYNOPSIS... UPPER LOW/TROUGH WILL CONTINUE RETREATING NEWD AWAY FROM THE NERN CONUS...WHILE A SECOND TROUGH -- CONSISTING OF A PHASED NRN AND SRN STREAM SYSTEM -- MOVES INTO THE ROCKIES THROUGH THE END OF THE PERIOD. A FEW CG LIGHTNING STRIKES HAVE OCCURRED DOWNSTREAM OF LK ONTARIO OVER THE PAST COUPLE OF HOURS...BUT EXPECT LIGHTNING POTENTIAL TO DIMINISH WITH TIME. THOUGH AN ADDITIONAL STRIKE OR TWO MAY OCCUR IN THIS AREA -- OR ACROSS PARTS OF WRN MT AND VICINITY AS NRN STREAM VORT MAX MOVES ACROSS THIS REGION DURING THE SECOND HALF OF THE PERIOD...IT APPEARS ATTM THAT NEITHER AREA REQUIRES 10% COVERAGE/PROBABILITY AREA. ..GOSS.. 10/29/2006  From swody1 at goshenarc.org Mon Oct 30 00:46:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 19:46:13 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300048 SWODY1 SPC AC 300047 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0647 PM CST SUN OCT 29 2006 VALID 300100Z - 301200Z ...NO TSTM AREAS FORECAST... IN WAKE OF THE STRONG UPPER CYCLONE EXITING NEW ENGLAND THIS EVENING...A FLOW OF CONTINENTAL POLAR AIR WILL DOMINATE THE ERN TWO-THIRDS OF THE COUNTRY. THIS WILL LIMIT TSTM PROSPECTS. IN THE WEST...A COLD UPPER TROUGH WAS DIGGING SEWD INTO THE NRN INTERMOUNTAIN REGION. ISOLD TSTMS HAVE BEEN OCCURRING ACROSS NRN ID AND ERN WA LATE THIS AFTN AS LAPSE RATES STEEPEN COINCIDENT WITH STRONG ASCENT. CONVECTION WILL LARGELY BE DIURNAL AND TSTM PROBABILITIES WILL DECREASE QUICKLY THIS EVE. ..RACY.. 10/30/2006  From swody1 at goshenarc.org Mon Oct 30 05:36:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 30 Oct 2006 00:36:29 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300539 SWODY1 SPC AC 300537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1137 PM CST SUN OCT 29 2006 VALID 301200Z - 311200Z ...NO SVR TSTM AREAS FORECAST... ...LWR OH VLY/OZARKS AND ERN PARTS OF THE SRN PLAINS... A SHORTWAVE TROUGH EMBEDDED WITHIN THE SRN BRANCH OF THE WLYS WILL MOVE FROM THE SRN GREAT BASIN EARLY MON TO THE SRN PLAINS BY EARLY TUE. A STRONGER NRN STREAM IMPULSE MOVING ACROSS THE INTERMOUNTAIN WEST EARLY IN THE DAY WILL AMPLIFY AS IT REACHES NRN MN BY 12Z TUE. THE ASSOCD COLD FRONT WILL SURGE SEWD IN WAKE OF THIS SYSTEM... REACHING A MI...SRN IL...SRN OK...NRN TX LINE BY EARLY TUE. HEIGHT FALLS SPREADING ACROSS THE ROCKIES WERE ALREADY RESULTING IN A MODEST RETURN FLOW REGIME ACROSS THE WRN GULF BASIN. THIS MOISTENING WILL CONTINUE FROM THE TX COASTAL PLAIN NWD INTO THE OZARKS THROUGH MONDAY BELOW AN H85 CAP. THE LOW-LEVEL FLOW IS EXPECTED TO TURN MORE ZONAL MON EVE...SHUNTING THE PRIMARY MOIST AXIS NEWD TOWARD THE LWR OH VLY. AS STRONGER LARGE SCALE ASCENT SPREADS EWD MON EVE COINCIDENT WITH THE SURGING COLD FRONT...THE COLUMN SHOULD SATURATE. THIS WILL CONTRIBUTE TO DESTABILIZATION AND SUBSEQUENT INCREASE IN ELEVATED CONVECTION ALONG NWRN EDGE OF THE MOISTURE PLUME. INITIAL TSTM DEVELOPMENT OVER CNTRL MO WILL SPREAD EWD INTO THE LWR OH VLY MON NIGHT...WITH TRAILING DEVELOPMENT PSBL INTO THE OZARKS AND ERN OK BY 12Z TUE TO THE N OF THE COLD FRONT. DESPITE FAVORABLE VERTICAL SHEAR... THERMODYNAMIC PROFILES SHOULD REMAIN UNFAVORABLE FOR SEVERE TSTMS. ..RACY.. 10/30/2006  From swody1 at goshenarc.org Mon Oct 30 17:55:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 30 Oct 2006 12:55:29 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301758 SWODY1 SPC AC 301756 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 1156 AM CST MON OCT 30 2006 VALID 301630Z - 311200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... A PROGRESSIVE SHORTWAVE TROUGH WILL MOVE FROM THE SWRN STATES INTO THE SRN PLAINS THROUGH TONIGHT. STEEP MID LEVEL LAPSE RATES ALONG WITH A PLUME OF MID LEVEL MOISTURE SHOULD SUPPORT ISOLATED TSTMS OVER PORTIONS OF THE SRN HIGH PLAINS AND FAR SRN ROCKIES THIS AFTERNOON. FURTHER AHEAD OF THIS SYSTEM...MODERATE SLY RETURN FLOW WILL SUPPORT CONTINUED LOW LEVEL MOISTURE TRANSPORT OVER ERN PORTIONS OF THE SRN PLAINS AND THE LOWER/MID MS VALLEY REGION. MEANWHILE...A NRN STREAM SHORTWAVE TROUGH OVER THE NRN ROCKIES WILL SHIFT EWD INTO THE NRN PLAINS. ASSOCIATED WITH THIS SYSTEM...A CANADIAN COLD FRONT WILL MOVE QUICKLY SWD THROUGH THE NRN/CENTRAL PLAINS THIS AFTERNOON...BEFORE EXTENDING FROM NRN TX INTO THE WRN GREAT LAKES BY TOMORROW MORNING. ...OZARK REGION... THE 12Z SHV SOUNDING INDICATED THE MOISTURE DEPTH WAS AROUND 1 KM...WITH A PRONOUNCED INVERSION ABOVE THIS LAYER. A THICK BAND OF MID/HIGH CLOUDS ASSOCIATED WITH THE APPROACHING SHORTWAVE TROUGH WILL TRANSITION ACROSS THE AREA THROUGH THE AFTERNOON. THE PRESENCE OF THIS CLOUD COVER IS ANTICIPATED TO INHIBIT FULL HEATING/MIXING POTENTIAL. STEADY SLY LOW LEVEL FLOW SHOULD ALLOW FOR DWPTS TO CONTINUE TO RISE INTO THE LOWER 60S BY LATE THIS EVENING. LOW LEVEL VERTICAL MOTION IS ANTICIPATED TO INCREASE OVERNIGHT AHEAD OF AN APPROACHING CANADIAN COLD FRONT AS A LOW LEVEL JET BECOMES BETTER DEFINED. AT THE SAME TIME...AN APPROACHING SHORTWAVE TROUGH AND ASSOCIATED COOLING MID LEVEL TEMPERATURES WILL SUPPORT STEEPENING LAPSE RATES. FCST SOUNDINGS INDICATE THAT JUST AHEAD OF THE COLD FRONT...SUFFICIENT LIFT/COOLING WILL DEVELOP TO ERODE THE LOW LEVEL INVERSION LAYER RESULTING IN SCT THUNDERSTORM DEVELOPMENT. ALTHOUGH MARGINAL INSTABILITY IS ANTICIPATED /MUCAPES FROM 750-1000 J/KG/ MODERATE MID LEVEL WIND FIELDS /50-60 KTS AT 500 MB/ WILL SUPPORT SUFFICIENT VERTICAL SHEAR FOR SOME STORM ROTATION. COMBINED WITH STEEP LAPSE RATES...ISOLATED MARGINALLY SVR HAIL WILL BE POSSIBLE. ..CROSBIE/EVANS.. 10/30/2006  From swody1 at goshenarc.org Sun Oct 1 05:58:33 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 01:58:33 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 010558 SWODY1 SPC AC 010556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT SUN OCT 01 2006 VALID 011200Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... SHARP UPPER TROUGH WILL CONTINUE MOVING EWD ACROSS THE ERN CONUS...WHILE FLATTER/LESS AMPLIFIED PATTERN PREVAILS ACROSS THE REMAINDER OF THE CONUS. AT THE SURFACE...A WEAK LOW IS FORECAST OVER THE LOWER GREAT LAKES REGION THROUGH THE FIRST HALF OF THE PERIOD...WHILE AN ASSOCIATED/OCCLUDED FRONT SHIFTS ACROSS SRN NEW ENGLAND. MEANWHILE...A COLD FRONT -- EXTENDING FROM A SURFACE LOW OVER MANITOBA -- IS FORECAST TO MOVE SEWD ACROSS THE NRN PLAINS. ...PORTIONS OF THE MID-ATLANTIC INTO SRN NEW ENGLAND... MODELS HINT THAT WEAK SURFACE-BASED INSTABILITY MAY BRUSH THE SRN NEW ENGLAND COAST EARLY IN THE PERIOD...AS TRIPLE POINT SHIFTS EWD ACROSS THIS REGION AND INTO THE ATLANTIC. THOUGH THIS SCENARIO REMAINS UNCERTAIN...FAVORABLY STRONG/VEERING FLOW WITH HEIGHT COULD SUPPORT A BRIEF TORNADO -- PRESUMING SURFACE-BASED INSTABILITY EXTENDS INLAND. MORE LIKELY SEVERE WEATHER THREAT HOWEVER MAY OCCUR LATER...AS DAYTIME HEATING BENEATH COLD AIR ALOFT ASSOCIATED WITH UPPER TROUGH YIELDS WEAK DESTABILIZATION. THOUGH DEEP-LAYER SHEAR WILL NOT BE PARTICULARLY STRONG...POCKETS OF INSTABILITY SUPPORTIVE OF A FEW STRONGER UPDRAFTS COULD EVOLVE FROM THE CHESAPEAKE BAY/ERN PA/SERN NY EWD ACROSS SRN NEW ENGLAND DURING THE AFTERNOON. A LOW-PROBABILITY THREAT FOR MARGINAL HAIL MAY ACCOMPANY THE STRONGER UPDRAFTS...BUT ANY THREAT SHOULD DIMINISH QUICKLY THROUGH THE EVENING...AS AIRMASS STABILIZES AND THE TROUGH AXIS SHIFTS OFF THE MID-ATLANTIC COAST. ...NRN IL/SRN WI AND VICINITY... NOCTURNAL STORM DEVELOPMENT APPEARS LIKELY AS SWLY LOW-LEVEL JET -- AHEAD OF SEWD-MOVING COLD FRONT -- SHIFTS EWD INTO THIS REGION AND INTENSIFIES. ASSOCIATED WARM ADVECTION ABOVE A STABLE BOUNDARY LAYER SHOULD YIELD SUFFICIENT ELEVATED INSTABILITY FOR A FEW STRONGER STORMS...AIDED BY 30 KT WLY FLOW FORECAST AT MID-LEVELS. GIVEN THE POTENTIAL FOR A FEW STRONGER STORMS...WILL MAINTAIN A LOW-PROBABILITY THREAT FOR HAIL. ..GOSS.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 12:45:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 08:45:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011244 SWODY1 SPC AC 011243 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0743 AM CDT SUN OCT 01 2006 VALID 011300Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...NJ TO SRN NEW ENGLAND TODAY... A DEEP MID LEVEL TROUGH OVER THE CENTRAL APPALACHIANS WILL MOVE EWD TO OFF THE SRN NEW ENGLAND AND MID ATLANTIC COASTS BY EARLY TONIGHT. A BAND OF RAIN/EMBEDDED THUNDERSTORMS WILL OVERSPREAD SRN NEW ENGLAND TODAY WITH THE WARM CONVEYOR BELT WHICH PRECEDES THE MID LEVEL WAVE. DESPITE THE STRONGER VERTICAL SHEAR...INSTABILITY WILL BE LIMITED UNTIL THE STEEPER LOW-MID LEVEL LAPSE RATES /6.5-7 C/KM/ ARRIVE WITH THE MID LEVEL COLD POOL /-22 C AT 500 MB/...LARGELY IN THE WAKE OF THIS PRECIPITATION BAND. BOUNDARY LAYER DEWPOINTS OF 56-62 F AND DAYTIME TEMPERATURES IN THE 60S WILL COMBINE WITH THE MODEST LAPSE RATES TO SUPPORT WEAK SURFACE-BASED INSTABILITY BY EARLY AFTERNOON /SBCAPE OF 250-500 J/KG/. VERTICAL SHEAR MAY SUPPORT SOME SUPERCELL OR SMALL BOWING STRUCTURES NEAR THE SRN NEW ENGLAND COAST TODAY WITHIN THE PRIMARY RAIN BAND...BUT WEAK INSTABILITY WILL TEND TO LIMIT THE SEVERE THREAT WITH THIS ACTIVITY. OTHERWISE...ADDITIONAL CONVECTION MAY FORM WITHIN THE MID LEVEL COLD POOL THIS AFTERNOON...WHERE SOME SMALL HAIL WILL BE POSSIBLE. ...SRN WI/SW LOWER MI AREA TONIGHT... A LEE TROUGH IS INDUCING SLY LOW-LEVEL FLOW AND LOW-LEVEL MOISTURE RETURN ACROSS THE SRN PLAINS. THIS MOISTURE /DEWPOINTS IN THE 50S TO LOWER 60S/ WILL SPREAD NWD/NNEWD ACROSS THE ERN PLAINS TOWARD THE UPPER MS VALLEY BY TONIGHT. THE MOISTURE RETURN WILL OCCUR BENEATH A WARM ELEVATED MIXED LAYER AND IN A REGIME OF HEIGHT RISES IN THE WAKE OF THE OH VALLEY TROUGH...THUS DEEP CONVECTION IS NOT EXPECTED TODAY. THE THREAT FOR ELEVATED THUNDERSTORMS WILL INCREASE LATE TONIGHT ACROSS SRN WI/SW LOWER MI AS PARCELS GRADUALLY APPROACH SATURATION IN THE 850-700 MB LAYER...WHERE WAA WILL BE MAXIMIZED ON THE NOSE OF A 40 KT LLJ. ELEVATED CAPE AND MID LEVEL LAPSE RATES MAY BECOME SUFFICIENT FOR SOME HAIL NEAR OR AFTER 06Z. ..THOMPSON/CROSBIE.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 16:25:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 12:25:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011625 SWODY1 SPC AC 011623 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1123 AM CDT SUN OCT 01 2006 VALID 011630Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...NORTHEAST STATES... LARGE UPPER TROUGH CONTINUES TO TRACK EASTWARD ACROSS THE NORTHEAST U.S. THIS MORNING...WHILE UPPER RIDGING DEVELOPS ACROSS THE PLAINS STATES. THE PRIMARY BAROCLINIC ZONE ASSOCIATED WITH THE EASTERN TROUGH IS MOVING EASTWARD ACROSS EASTERN NY. STRONG LOW LEVEL WARM ADVECTION AND FORCING ARE PRODUCING WIDESPREAD PRECIPITATION AND CLOUDS THROUGHOUT SOUTHERN/CENTRAL NEW ENGLAND. VERY LIMITED LAPSE RATES AND CAPE VALUES SUGGEST THAT SEVERE THREAT IS LOW...DESPITE IMPRESSIVE LOW LEVEL AND DEEP LAYER VERTICAL SHEAR PROFILES. THERE REMAINS A SMALL AREA FROM RI INTO EASTERN MA WHERE SUFFICIENT LOW LEVEL INSTABILITY COULD RESULT IN LOCALLY DAMAGING WIND GUSTS. HOWEVER...THE THREAT AREA HAS BECOME QUITE SMALL AND SHOULD END BY MID AFTERNOON AS CONVECTIVE LINE MOVES OFFSHORE. IN THE WAKE OF THIS ACTIVITY...CLEARING SKIES WILL ALLOW STRONG HEATING FROM THE NYC AREA WESTWARD INTO PARTS OF EASTERN PA/NJ INTO THE DELMARVA. LOW LEVEL COLD/DRY ADVECTION SHOULD MINIMIZE DEEP CONVECTIVE THREAT. HOWEVER...SOME MODEL GUIDANCE MAINTAINS A RISK OF LOW-TOPPED AFTERNOON SHOWERS/THUNDERSTORMS ACROSS THIS REGION. IF STORMS CAN FORM...COLD THERMODYNAMIC PROFILES WOULD BE FAVORABLE FOR HAIL. THEREFORE...WILL MAINTAIN LOW PROBABILITIES. ...WI/IL... UPPER RIDGING IS OCCURRING ACROSS THE MIDWEST TODAY...ATOP RATHER DRY/STABLE CONDITIONS. STRONG LOW LEVEL WARM/MOIST ADVECTION WILL OCCUR THROUGH TONIGHT RESULTING IN MARGINAL ELEVATED INSTABILITY BY THIS EVENING. MODEL FORECAST SOUNDINGS SUGGEST THAT UNSTABLE LEVEL WILL BE ROOTED ABOVE 700MB...AND WILL YIELD CAPE VALUES BELOW 500 J/KG. GIVEN THIS SCENARIO...IT APPEARS LIKELY THAT OVERNIGHT CONVECTION THAT MAY DEVELOP IN THIS REGION WILL PROBABLY BE NON-SEVERE. ..HART/GRAMS.. 10/01/2006  From swody1 at goshenarc.org Sun Oct 1 19:52:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 15:52:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 011951 SWODY1 SPC AC 011950 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0250 PM CDT SUN OCT 01 2006 VALID 012000Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...LOWER HUDSON VALLEY INTO SRN NEW ENGLAND... AFTERNOON WATER VAPOR IMAGERY SHOWS NEGATIVELY-TILTED SHORT WAVE TROUGH LIFTING NEWD THROUGH THE HUDSON VALLEY WITH AN ASSOCIATED BAND OF STRONG DEEP-LAYER FORCING FOR ASCENT PRECEDING THIS FEATURE OVER WRN INTO CNTRL PARTS OF NEW ENGLAND. IN THE LOW-LEVELS...MESOANALYSIS INDICATED LOW PRESSURE OVER CT WITH ATTENDANT WEAK WARM FRONT EXTENDING EWD THROUGH CAPE COD...WHILE PRIMARY FRONTAL ZONE STRETCHED NW-SE FROM THE ADIRONDACKS THROUGH THIS LOW PRESSURE TO OFF LONG ISLAND. CONSIDERABLE CLOUDS AND PRECIPITATION ARE LIMITING AIR MASS DESTABILIZATION AHEAD OF THIS LOW PRESSURE CENTER AND ALONG AND N OF WARM FRONT ACROSS MUCH OF NEW ENGLAND...HOWEVER BREAKS IN THE CLOUDS HAVE ALLOWED FOR STRONG DIABATIC HEATING AND RESULTANT DESTABILIZATION /SBCAPES OF 500 J/KG/ NEAR AND IN THE WAKE OF FRONTAL ZONE OVER THE LOWER HUDSON VALLEY. VERTICAL SHEAR IS NOT PARTICULARLY STRONG OWING TO CLOSE PROXIMITY OF MID-LEVEL TROUGH AXIS...THOUGH THE PRESENCE OF STEEP LAPSE RATES AND COOL TEMPERATURES PROFILES MAY SUPPORT SOME MARGINALLY SEVERE HAIL/WIND WITH THE STRONGEST STORMS. FARTHER E ACROSS SRN NEW ENGLAND...A LOW SEVERE THREAT WILL BE DEPENDANT ON DEGREE OF DESTABILIZATION THAT CAN OCCUR AHEAD OF SURFACE LOW AND ALONG WARM FRONT THE REMAINDER OF THIS AFTERNOON INTO EVENING. ...UPPER MIDWEST... POTENTIAL FOR ELEVATED TSTMS WILL EXIST TONIGHT WITH ZONE OF STRONG THERMAL/MOIST ADVECTION DEVELOPING ALONG NOSE OF 35-45 KT LLJ. HOWEVER...THE PRESENCE OF WARM LOWER TROPOSPHERIC TEMPERATURES SUGGEST THAT CONSIDERABLE ISENTROPIC ASCENT WILL BE NECESSARY TO FORCE PARCELS TO THEIR LFC...EFFECTIVELY DECREASING POTENTIAL ELEVATED INSTABILITY. STILL...SOME SMALL HAIL WILL BE POSSIBLE WITH THE STRONGEST CELLS. ..MEAD.. 10/01/2006  From swody1 at goshenarc.org Mon Oct 2 00:36:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 01 Oct 2006 20:36:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020035 SWODY1 SPC AC 020034 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0734 PM CDT SUN OCT 01 2006 VALID 020100Z - 021200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... MAIN UPPER TROUGH OVER THE NERN U.S. WILL CONTINUE MOVING EWD THROUGH THE PERIOD...WHILE FLATTER/LESS-AMPLIFIED UPSTREAM FLOW PATTERN WILL PREVAIL THROUGH THE END OF THE PERIOD. BROAD ZONE OF WARM ADVECTION EXISTS ACROSS THE N CENTRAL CONUS ATTM...WITH 35-40 KT SWLY LOW-LEVEL JET INDICATED FROM N CENTRAL OK NEWD INTO WI. ISOLATED/ELEVATED STORMS HAVE DEVELOPED ACROSS SRN WI/NRN IL IN RESPONSE...AND AN INCREASE IN CONVECTIVE COVERAGE IS FORECAST OVER THE NEXT SEVERAL HOURS ACROSS THIS REGION AND SEWD INTO LOWER MI/INDIANA. EVENING RAOBS ACROSS THIS REGION CONFIRM ONLY MODEST ELEVATED CAPE...AND MARGINAL CLOUD-LAYER SHEAR. THEREFORE...THOUGH SMALL HAIL MAY OCCUR WITH A FEW STRONGER STORMS...MOST IF NOT ALL HAIL SHOULD REMAIN SUB-SEVERE. ELSEWHERE...A COUPLE OF LIGHTNING STRIKES MAY LINGER BEYOND 02/01Z OVER SRN NEW ENGLAND...CENTRAL AND NRN MS...AND THE TX BIG BEND AREA...BUT EXPECT CONVECTION/LIGHTNING THREAT TO TAPER OFF THROUGH MID-EVENING IN THESE AREAS. ..GOSS.. 10/02/2006  From swody1 at goshenarc.org Mon Oct 2 05:57:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 02 Oct 2006 01:57:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 020535 SWODY1 SPC AC 020533 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1233 AM CDT MON OCT 02 2006 VALID 021200Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE UPPER MS VALLEY/UPPER GREAT LAKES REGION... ...SYNOPSIS... A SERIES OF WEAK MID-LEVEL SHORT-WAVE TROUGHS ARE FORECAST TO MOVE EWD ACROSS THE NRN PLAINS INTO THE UPPER MS VALLEY/UPPER GREAT LAKES ...THROUGH LARGE-SCALE MEAN RIDGE. THIS FLAT RIDGE WILL PREVAIL ACROSS THE MAJORITY OF THE CONUS THROUGH THE PERIOD...AS ERN TROUGH MOVES INTO THE N ATLANTIC AND WRN TROUGH REMAINS OVER THE ERN PACIFIC/WRN CONUS. AT THE SURFACE...A COLD FRONT IS FORECAST TO MOVE SLOWLY SWD/SEWD ACROSS THE N CENTRAL CONUS WHILE BECOMING ORIENTED INCREASINGLY E-W WITH TIME...AS EWD-SURGE OF FRONT IS FORECAST FURTHER N ACROSS ONTARIO. MEANWHILE...A WEAK LOW IS FORECAST TO MOVE ENEWD ALONG THIS FRONT INTO THE MID MO VALLEY REGION DURING THE LATTER HALF OF THE PERIOD. ...UPPER MS VALLEY/UPPER GREAT LAKES REGION... THUNDERSTORMS WILL LIKELY BE ONGOING AT THE START OF THE PERIOD ACROSS PARTS OF THE UPPER GREAT LAKES REGION...IN ZONE OF WARM ADVECTION NEAR THE NOSE OF A VEERING LOW-LEVEL JET. AS THIS CONVECTION SHIFTS EWD/SEWD WITH TIME INTO LOWER MI/IN...DESTABILIZATION SHOULD OCCUR OVER THE UPPER MS VALLEY AS LOW-LEVEL MOISTURE ADVECTS NWD INTO THIS REGION AHEAD OF COLD FRONT...AND BENEATH ELEVATED MIXED LAYER. PRESUMING SOME HEATING CAN OCCUR IN THE WAKE OF INITIAL CONVECTION...MODERATE AIRMASS DESTABILIZATION SHOULD OCCUR -- THOUGH BOUNDARY LAYER WILL LIKELY REMAIN CAPPED WELL INTO THE AFTERNOON. AS COLD FRONT MOVES SEWD INTO THIS REGION DURING THE AFTERNOON/EVENING...SCATTERED CONVECTIVE DEVELOPMENT IS FORECAST. STORMS ARE EXPECTED TO CONTINUE/SPREAD EWD INTO THE OVERNIGHT HOURS...AS SURFACE LOW SHIFTS EWD TOWARD THE REGION IN CONJUNCTION WITH AN UPPER IMPULSE MOVING EWD ACROSS THE PLAINS DURING THE LATTER HALF OF THE PERIOD. DEEP-LAYER SHEAR IS FORECAST TO REMAIN GENERALLY MARGINAL FOR WELL-ORGANIZED STORMS...WITH FASTER WLY FLOW ALOFT REMAINING N OF THE U.S./CANADA BORDER. HOWEVER...GIVEN DEGREE OF INSTABILITY WHICH WILL LIKELY EVOLVE...A FEW STRONGER MULTICELL CLUSTERS AND PERHAPS A COUPLE SUPERCELL STORMS WILL BE POSSIBLE. MAIN SEVERE THREAT SHOULD BE HAIL...THOUGH LOCALLY-DAMAGING WINDS WILL ALSO BE POSSIBLE -- MAINLY DURING THE AFTERNOON AND EARLY EVENING. ..GOSS.. 10/02/2006  From swody1 at goshenarc.org Mon Oct 2 12:43:18 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 02 Oct 2006 08:43:18 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 021242 SWODY1 SPC AC 021241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT MON OCT 02 2006 VALID 021300Z - 031200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY INTO TONIGHT FROM NE IA TO SW LOWER MI... ...NE IA TO SW LOWER MI AREA THROUGH TONIGHT... SRN STREAM OF THE WLYS...FROM SRN CA NEWD TO THE CENTRAL HIGH PLAINS AND THEN EWD TO THE MS VALLEY...WILL HELP MAINTAIN A LEE CYCLONE INVOF N/NE NEB THROUGH THE PERIOD. A BAROCLINIC ZONE EXTENDS NEWD FROM THE LEE CYCLONE...AND THIS BOUNDARY WILL MOVE SEWD ACROSS WI/MI IN THE WAKE OF A NRN STREAM WAVE CROSSING NW ONTARIO BY LATE TONIGHT. PERSISTENT SLY/SWLY LOW-LEVEL FLOW ACROSS THE ERN PLAINS WILL MAINTAIN AN INFLUX OF MOISTURE /BOUNDARY LAYER DEWPOINTS IN THE 60S/ ACROSS THE CORN BELT...BENEATH STEEP MID LEVEL LAPSE RATES. ONGOING ELEVATED CONVECTION OVER LAKE MI/SW LOWER MI MAY PERSIST THROUGH THE FIRST HALF OF THE DAY OVER LOWER MI AND NRN INDIANA IN CONJUNCTION WITH THE LLJ AND CONTINUED WAA ATOP THE COLD POOL GENERATED BY THE CONVECTION. ADDITIONAL THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE BY LATE AFTERNOON/EVENING ACROSS NE IA/CENTRAL AND SRN WI/NRN IL AS LOW-LEVEL MOISTENING AND NEAR RECORD MAXIMUM TEMPERATURES /85-90 F/ GRADUALLY WEAKEN CONVECTIVE INHIBITION...AND A WEAK MID LEVEL WAVE MOVES EWD FROM NE NEB THIS MORNING TO IA/NRN IL BY THIS EVENING. POTENTIALLY STRONG INSTABILITY /8 C/KM LAPSE RATES AND MLCAPE OF 2000-3000 J/KG/ WILL SUPPORT INTENSE UPDRAFTS CAPABLE OF PRODUCING AT LEAST ISOLATED LARGE HAIL...ALONG WITH THE THREAT FOR ISOLATED DAMAGING DOWNBURST WINDS. DEEP LAYER VERTICAL SHEAR...HOWEVER...IS EXPECTED TO BE RATHER MODEST /0-6 KM BULK SHEAR OF 20-30 KT/...AND CONVECTIVE MODE SHOULD CONSIST PRIMARILY OF MULTICELL CLUSTERS THROUGH LATE TONIGHT AS CONVECTION OVERSPREADS NRN INDIANA/SRN LOWER MI. ..THOMPSON/CROSBIE.. 10/02/2006  From swody1 at goshenarc.org Wed Oct 4 01:01:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 03 Oct 2006 21:01:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040101 SWODY1 SPC AC 040059 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0759 PM CDT TUE OCT 03 2006 VALID 040100Z - 041200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID MO VALLEY EWD ACROSS SRN PORTIONS OF THE UPPER GREAT LAKES... ...MID MO VALLEY AND SRN MN EWD ACROSS LOWER MI... STRONG/LOCALLY-SEVERE STORMS ARE MOVING EWD ACROSS CENTRAL AND NRN WI ATTM...N OF SURFACE WARM FRONT WHICH NOW EXTENDS FROM A LOW NEAR SIOUX CITY IA ENEWD ACROSS SRN MN...AND THEN SEWD ACROSS CENTRAL WI INTO THE CHICAGO AREA. THOUGH STORMS REMAIN ELEVATED...MODERATE INSTABILITY IS INDICATED ABOVE THE SURFACE STABLE LAYER -- PER EVENING MINNEAPOLIS AND GREEN BAY SOUNDINGS -- WHICH IS SUPPORTING VIGOROUS STORMS. OVERNIGHT...EXPECT STORM COVERAGE TO INCREASE N OF WARM FRONT AND SPREAD EWD ACROSS LK MI INTO LOWER MI...AS INTENSIFYING SWLY LOW-LEVEL JET VEERS WITH TIME. MEANWHILE...DEVELOPMENT WITHIN WARM SECTOR ACROSS IA REMAINS MORE UNCERTAIN. EVENING SOUNDINGS REVEAL A RELATIVELY DRY LOWER TROPOSPHERE...AND A CAPPED BOUNDARY LAYER. THOUGH APPROACH OF SEVERAL UPPER FEATURES FROM THE W MAY AID IN ISOLATED STORM DEVELOPMENT NEAR SURFACE LOW AND SWWD ALONG SLOWLY ADVANCING COLD FRONT...THE MAJORITY OF THE CONVECTION SHOULD REMAIN ALONG AND N OF WARM FRONT ACROSS WI AND LOWER MI. ALONG WITH SUBSTANTIAL INSTABILITY...EVENING RAOBS REVEAL SHEAR FAVORABLE FOR SUPERCELLS ACROSS MN AND INTO WI...WITH 40 TO 60 KT WLY FLOW AT MID-LEVELS. THIS SUGGESTS THAT LARGE HAIL REMAINS LIKELY WITH ONGOING ELEVATED CONVECTION. GREATEST THREAT FOR DAMAGING WINDS SHOULD REMAIN ACROSS SRN WI AND PERHAPS INTO NERN IA/NRN IL...WHERE SURFACE-BASED OR NEAR SURFACE-BASED CONVECTION WOULD BE POSSIBLE. A FEW TORNADOES ALSO REMAIN POSSIBLE ACROSS THIS REGION...AS SELY BOUNDARY LAYER FLOW INVOF WARM FRONT IS RESULTING IN FAVORABLE LOW-LEVEL SHEAR. DAMAGING WIND/TORNADO THREAT SHOULD SPREAD EWD ACROSS LK MI INTO LOWER MI LATER THIS EVENING. ..GOSS.. 10/04/2006  From swody1 at goshenarc.org Wed Oct 4 04:50:25 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 04 Oct 2006 00:50:25 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 040450 SWODY1 SPC AC 040448 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1148 PM CDT TUE OCT 03 2006 VALID 041200Z - 051200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NY/PA WSWWD ACROSS THE OH VALLEY... ...SYNOPSIS... MID-LEVEL SHORT-WAVE TROUGH WILL MOVE ACROSS THE OH VALLEY/GREAT LAKES REGION THIS PERIOD...ON NRN PERIPHERY OF S CENTRAL U.S. UPPER RIDGE. AS THE TROUGH REACHES THE ERN CONUS...THE OVERALL UPPER FLOW FIELD WILL AMPLIFY...AS RIDGE EXPANDS NWD ACROSS THE CENTRAL CONUS UPSTREAM OF ERN TROUGH AND DOWNSTREAM OF LARGE UPPER LOW/TROUGH OVER THE W COAST. AT THE SURFACE...A N-S BAROCLINIC ZONE IS FORECAST TO REMAIN ROUGHLY STATIONARY ACROSS THE GREAT BASIN AND SRN CA AHEAD OF UPPER LOW. MEANWHILE...THE COLD FRONT ASSOCIATED WITH THE ERN U.S. SHORT-WAVE TROUGH IS INITIALLY FORECAST TO EXTEND FROM LOWER MI WSWWD INTO OK AND THE SRN TX PANHANDLE. BY LATE AFTERNOON/EARLY EVENING...THE FRONT IS FORECAST TO EXTEND FROM NEW ENGLAND WSWWD ALONG THE OH RIVER AND THEN INTO CENTRAL OK...AND THEN WILL CONTINUE SHIFTING SEWD THROUGH THE END OF THE PERIOD. ...NY/PA WSWWD ACROSS THE OH VALLEY... CONVECTION WILL BE ONGOING INVOF FRONT AT THE START OF THE PERIOD...AND WILL CONTINUE/SHIFT SEWD WITH TIME IN CONJUNCTION WITH THE FRONT. THIS WILL HINDER THE POTENTIAL FOR SIGNIFICANT HEATING/DESTABILIZATION ACROSS PARTS OF THE REGION -- PARTICULARLY ACROSS OH/PA/NY -- DURING THE DAY. NONETHELESS...WITH 35 TO 45 KT MID-LEVEL FLOW SPREADING SEWD ACROSS THE MID AND UPPER OH VALLEY...EXPECT LOCALLY-DAMAGING WINDS AND SOME HAIL WITH STORMS ORGANIZED LINEARLY ALONG/AHEAD OF FRONT. SOMEWHAT GREATER DESTABILIZATION WILL BE POSSIBLE FROM SWRN OH SWWD ALONG FRONT...BUT WITH DEEP-LAYER WIND FIELD EXPECTED TO BE WEAKER WITH SWWD EXTENT ALONG THE FRONT...THREAT FOR HAIL/DAMAGING WINDS SHOULD STILL REMAIN RELATIVELY LOW. THEREFORE...WILL MAINTAIN 15% SEVERE PROBABILITY ALONG THE FRONT ACROSS THIS REGION...WITH THREAT LIKELY DIMINISHING DURING THE EVENING AS BOUNDARY LAYER STABILIZES AND FRONT SHIFTS SEWD AWAY FROM THE STRONGER FLOW ALOFT. ...ID AND VICINITY... MARGINAL INSTABILITY IS FORECAST ACROSS PARTS OF THE GREAT BASIN AND NWRN CONUS...THOUGH ONGOING STORMS AT THE BEGINNING OF THE PERIOD SHOULD LIMIT OVERALL DEGREE OF DESTABILIZATION. GREATEST INSTABILITY IS FORECAST BY THE MODELS ACROSS ERN OREGON AND INTO ID...BENEATH DIFFLUENT UPPER FLOW ON NERN PERIPHERY OF UPPER LOW. EXPECT STORMS TO REDEVELOP/INCREASE DURING THE AFTERNOON...WITH A FEW STRONGER/ORGANIZED UPDRAFTS POSSIBLE GIVEN ENHANCED /AROUND 40 KT/ SLY MID-LEVEL FLOW ACROSS THIS REGION. THOUGH MARGINAL INSTABILITY WILL TEMPER OVERALL SEVERE THREAT...MARGINAL HAIL OR A LOCALLY STRONGER GUST OR TWO MAY OCCUR WITH MORE INTENSE CONVECTIVE CELLS THROUGH EARLY EVENING. ..GOSS/TAYLOR.. 10/04/2006  From swody1 at goshenarc.org Thu Oct 5 05:38:44 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 01:38:44 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 050538 SWODY1 SPC AC 050536 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1236 AM CDT THU OCT 05 2006 VALID 051200Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... SIGNIFICANT AMPLIFICATION OF LARGE SCALE MID/UPPER LEVEL FLOW WILL OCCUR ACROSS THE CONUS THIS PERIOD AS CURRENT SPLIT-FLOW REGIME UNDERGOES A TRANSITION TO MORE OF AN OMEGA-BLOCK CONFIGURATION CENTERED ON THE CNTRL U.S. BY FRIDAY MORNING. DEEP CLOSED LOW OFF THE WEST COAST WILL EDGE SLOWLY INLAND AND EWD TOWARD THE GREAT BASIN TODAY WHILE DOWNSTREAM SUB-TROPICAL RIDGE MAINTAINS ITS DOMINANCE ACROSS THE SOUTH...AND EXPANDS OVER THE CNTRL AND NRN PLAINS. A LEAD SHORT WAVE TROUGH AND ASSOCIATED FRONT WILL MOVE OFF THE NEW ENGLAND COAST TODAY AS THE NEXT UPSTREAM TROUGH DEVELOPS SEWD AND AMPLIFIES ACROSS THE GREAT LAKES THROUGH TONIGHT. STRONGEST HEIGHT FALLS WITH THIS TROUGH WILL MOVE TOWARD THE MID ATLANTIC REGION THROUGH EARLY FRIDAY...EVENTUALLY INDUCING SECONDARY CYCLOGENESIS ALONG THE COLD FRONT TRAILING FROM LEAD SYSTEM. ...CNTRL APPALACHIANS ACROSS VA/NC... LOW LEVEL WIND SHIFT/BACK DOOR FRONT ASSOCIATED WITH UPPER TROUGH CROSSING NEW ENGLAND IS EXPECTED TO SETTLE SWD/SWWD ACROSS ERN AND SRN VA/NRN NC THROUGH THE AFTERNOON. NEUTRAL LARGE SCALE UPPER FORCING FOR ASCENT WILL EXIST ACROSS THE REGION BETWEEN DEPARTING SHORT WAVE TROUGH AND AMPLIFYING UPSTREAM SYSTEM OVER THE GREAT LAKES. NONETHELESS...OROGRAPHIC LIFT AND MESOSCALE FORCING NEAR THE BOUNDARY...ALONG WITH WEAK TO LOCALLY MODEST DIURNAL DESTABILIZATION...SHOULD PROVE SUFFICIENT FOR TSTM DEVELOPMENT OVER PARTS OF VA/NC...AND ERN KY/TN...THROUGH AFTERNOON. WITH INSTABILITY AND SHEAR ACROSS THE AREA EXPECTED TO REMAIN GENERALLY WEAK DURING THIS TIME FRAME...SEVERE HAIL/WIND POTENTIAL SHOULD BE LIMITED. LARGE SCALE FORCING FOR ASCENT AND DEEP LAYER SHEAR SHOULD INCREASE STEADILY ACROSS THE MID ATLANTIC REGION THROUGH LATE EVENING AS THE MID/UPPER LEVEL TROUGH DIGS SEWD FROM THE GREAT LAKES. IT IS POSSIBLE THAT STORM ORGANIZATION AND COVERAGE COULD INCREASE DURING THIS TIME IF INSTABILITY CAN PERSIST INTO THE EVENING HOURS. GIVEN UNCERTAINTY IN AVAILABLE INSTABILITY AFTER DARK...HIGHER SEVERE WEATHER PROBABILITIES WILL NOT BE ISSUED AT THIS TIME. ...SOUTHWEST TO GREAT BASIN... AN EXTENSIVE SWATH OF STRONG DEEP LAYER MERIDIONAL FLOW WILL PERSIST AHEAD OF THE PACIFIC COAST TROUGH AND CONTRIBUTE TO CONTINUED NWD TRANSPORT OF EAST PACIFIC MOISTURE ACROSS THE SRN PLATEAU AND GREAT BASIN REGIONS. CLOUD COVER...PRECIPITATION...AND MEAGER LOW LEVEL MOISTURE ARE EXPECTED TO LIMIT MORE WIDESPREAD STRONG DESTABILIZATION. HOWEVER...POCKETS OF STRONGER INSOLATION... OROGRAPHIC FORCING...AND IMPULSES ROTATING THROUGH THE LARGE SCALE TROUGH...WILL ALL SUPPORT EPISODIC DEVELOPMENT OF BANDS/LINES OF DEEP CONVECTION SPREADING OVER A LARGE REGION. THIS ACTIVITY WILL EXIST WITHIN STRONG UNIDIRECTIONAL SHEAR AND IT IS POSSIBLE THAT LINE SEGMENTS AND CELLS COULD BECOME BETTER ORGANIZED AND PERSISTENT AS LOCALLY STRONGER INSTABILITY IS ENCOUNTERED AND/OR STRONGER FORCING IS REALIZED DURING THE FORECAST PERIOD. WHILE SMALL SCALE LEWPS AND BOWS WITH ENHANCED DOWNBURST WIND AND HAIL THREAT APPEAR POSSIBLE...AN ACCURATE DEPICTION OF AN AREA OF GREATER SEVERE WEATHER POTENTIAL IS NOT POSSIBLE AT THIS TIME. PARTS OF THE REGION MAY BE UPGRADED IN LATER OUTLOOKS AS MESOSCALE DETAILS BECOME BETTER DEFINED. ..CARBIN.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 12:43:50 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 08:43:50 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051242 SWODY1 SPC AC 051241 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 AM CDT THU OCT 05 2006 VALID 051300Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... A MORE AMPLIFIED PATTERN WILL EVOLVE OVER THE CONUS THROUGH TOMORROW AS A MID LEVEL RIDGE BUILDS OVER THE PLAINS DOWNSTREAM FROM THE CLOSED LOW OVER CA...AND A SEPARATE SHORTWAVE TROUGH OVER WRN ONTARIO/LAKE SUPERIOR DIGS SEWD TO THE UPPER OH VALLEY/CENTRAL APPALACHIANS. THE PRIMARY THUNDERSTORM THREAT AREAS WILL BE ACROSS A BROAD SWATH OF THE GREAT BASIN IN ADVANCE OF THE CA LOW...AND INVOF THE SRN APPALACHIANS IN ADVANCE OF THE DIGGING TROUGH. ...GREAT BASIN THROUGH TONIGHT... A BROAD PLUME OF MID LEVEL MOISTURE FROM THE ERN PACIFIC WILL PERSIST OVER AZ/UT AND ADJACENT STATES WITHIN THE WARM CONVEYOR BELT E OF THE SLOW MOVING LOW NEAR THE CENTRAL CA COAST. A BELT OF 45-65 KT SLY/SSWLY MID LEVEL FLOW WILL COINCIDE WITH THE MOISTURE PLUME...RESULTING IN SUFFICIENT DEEP LAYER VERTICAL SHEAR FOR ORGANIZED/PERSISTENT THUNDERSTORMS THROUGH THE PERIOD FROM WRN AZ NWD OVER UT/NV TO SRN ID. HOWEVER...WIDESPREAD CLOUDS AND POOR MID LEVEL LAPSE RATES WITHIN THE MOISTURE PLUME WILL TEND TO LIMIT THE DEGREE OF INSTABILITY. POCKETS OF SURFACE HEATING WITHIN CLOUD BREAKS MAY ALLOW SUFFICIENT DESTABILIZATION FOR SUPERCELLS AND/OR SHORT BOWING SEGMENTS WITH LARGE HAIL AND DAMAGING GUSTS. HOWEVER...ANY SUCH FAVORED AREAS OF SURFACE HEATING...AS WELL AS EMBEDDED SPEED MAXIMA TO HELP FOCUS THUNDERSTORM DEVELOPMENT...ARE DIFFICULT TO DISCERN AT THIS TIME. THEREFORE...A LARGE AREA OF 5% HAIL/WIND PROBABILITIES WILL BE MAINTAINED...ALONG WITH THE POSSIBILITY OF AN UPGRADE TO PORTIONS OF THIS AREA DURING THE DAY IF THE THREAT BECOMES MORE FOCUSED/APPARENT. ...NRN CA/S CENTRAL ORE TODAY... SCATTERED THUNDERSTORMS WILL LIKELY CONTINUE THROUGH THE DAY FROM N/NE CA INTO SRN ORE IN THE REGION OF PRONOUNCED ASCENT N/NE OF THE CLOSED LOW ALONG THE CENTRAL CA COAST. THOUGH VERTICAL SHEAR WILL BE RELATIVELY WEAK...COOL MID LEVEL TEMPERATURES AND STEEP LAPSE RATES MAY SUPPORT MARGINALLY SEVERE HAIL IN THE STRONGER STORMS. ...ERN TN/KY INTO NC/VA THIS AFTERNOON/EARLY TONIGHT... A SURFACE COLD FRONT WILL CONTINUE SLOWLY SEWD ACROSS TN/KY TO THE SRN APPALACHIANS LATE TODAY...AND SWD ACROSS VA INTO NC. THE FRONT WILL BE ACCOMPANIED BY A WEAK MID LEVEL TROUGH TODAY OVER THE SRN APPALACHIANS...WHILE WEAK CYCLOGENESIS IS EXPECTED OVER THE CAROLINAS ALONG THE FRONT AND IN ADVANCE OF A STRONGER/LARGER SCALE WAVE DIGGING TOWARD THE CENTRAL APPALACHIANS BY LATE TONIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TODAY INTO TONIGHT ALONG THE FRONT. AFTERNOON MLCAPE VALUES OF 1000-1500 J/KG ACROSS ERN TN/SE KY MAY SUPPORT A FEW STRONG STORMS...BUT THE OVERALL SEVERE THREAT WILL BE LIMITED BY BOTH RELATIVELY WEAK MID LEVEL LAPSE RATES AND VERTICAL SHEAR IN THE WARM SECTOR FROM ERN TN/KY INTO THE CAROLINAS THIS AFTERNOON. SOMEWHAT STRONGER VERTICAL SHEAR IS EXPECTED ALONG AND IMMEDIATELY N OF THE E-W FRONT ACROSS SRN VA/NRN NC THIS AFTERNOON INTO EARLY TONIGHT...BUT WEAK INSTABILITY WILL KEEP ANY SEVERE STORM THREAT QUITE MARGINAL IN THIS AREA. ..THOMPSON/TAYLOR.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 16:32:20 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 12:32:20 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051631 SWODY1 SPC AC 051630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT THU OCT 05 2006 VALID 051630Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SOUTHEAST ID AND NORTHWEST UT... ...UT/ID... MORNING SATELLITE LOOPS SHOW A DEEP UPPER LOW OFF THE CENTRAL CA COAST...WITH SEVERAL FEATURES EMBEDDED IN FAST SOUTHWESTERLY FLOW FROM CA ACROSS NV/UT INTO ID. WIDESPREAD AND AMPLE MID LEVEL MOISTURE IN MOIST CONVEYOR BELT FROM SOUTHERN NV ACROSS UT WILL LIKELY RESULTING IN CLOUDS AND LESSENED DAYTIME HEATING. HOWEVER...STEEP LOW LEVEL LAPSE RATES MAY DEVELOP ALONG WEST EDGE OF CLOUDS FROM NORTHWEST UT INTO SOUTHEAST ID. FORECAST SOUNDINGS IN THIS AREA SHOW MLCAPE VALUES OVER 500 J/KG...PROMOTING THE DEVELOPMENT OF SCATTERED AFTERNOON AND EVENING THUNDERSTORMS. ALTHOUGH MID LEVEL TEMPERATURES ARE SLIGHTLY WARMER AND TIMING OF UPPER FEATURES DO NOT APPEAR AS FAVORABLE AS YESTERDAY...COVERAGE OF STORMS MAY BE GREATER DUE TO AMPLE MID LEVEL MOISTURE. VERTICAL SHEAR VALUES AND POTENTIAL FOR DESTABILIZATION SUGGEST A RISK OF DAMAGING WINDS AND HAIL IN STRONGER STORMS. ...CENTRAL APPALACHIANS... SOUTHERN FRINGE OF STRONGER WESTERLIES EXTENDS FROM KY/TN INTO VA/NC. SCATTERED AFTERNOON THUNDERSTORMS ARE LIKELY TO INCREASE AHEAD OF WEAKENING SURFACE FRONT SWEEPING THROUGH THE REGION. SURFACE DEWPOINTS IN THE 60S AND STRONG HEATING WILL RESULT IN MLCAPE VALUES OF 800-1200 J/KG. HOWEVER...WEAKER WIND FIELDS AND LAPSE RATES THAN PAST FEW DAYS SUGGEST THAT OVERALL SEVERE THREAT IS RATHER MARGINAL. NEVERTHELESS...STRONGEST CELLS COULD PRODUCE LOCALLY GUSTY WINDS AND HAIL. ..HART/JEWELL.. 10/05/2006  From swody1 at goshenarc.org Thu Oct 5 19:43:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 15:43:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 051943 SWODY1 SPC AC 051941 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0241 PM CDT THU OCT 05 2006 VALID 052000Z - 061200Z ...THERE IS A SLGT RISK OF SVR TSTMS LATE THIS AFTN ACROSS PARTS OF THE GREAT BASIN/NRN INTERMOUNTAIN REGION.... ...INTERMOUNTAIN WEST... THE MOST SIGNIFICANT SHORT WAVE IMPULSE ASSOCIATED WITH THE WESTERN U.S. UPPER TROUGH STILL APPEARS TO BE DIGGING AROUND THE SOUTHWESTERN PERIPHERY OF A CLOSED LOW NEAR THE CENTRAL CALIFORNIA COAST. HOWEVER...DEEP LAYER SOUTHERLY FLOW AHEAD OF LARGE SCALE TROUGH AXIS CONTINUES TO TRANSPORT MOISTURE NORTHWARD FROM THE LOWER LATITUDE EASTERN PACIFIC...TOWARD THE SOUTHERN PLATEAU/GREAT BASIN. INCREASING MOISTURE/OROGRAPHY AND FURTHER SURFACE HEATING IS EXPECTED TO CONTRIBUTE TO SUBSTANTIAL CONVECTIVE DEVELOPMENT LATE THIS AFTERNOON FROM PARTS OF ARIZONA INTO SOUTHERN/EASTERN PORTIONS OF THE GREAT BASIN. ENHANCED BY FAVORABLE DEEP LAYER SHEAR BENEATH 40-50 KT SOUTHWESTERLY MID-LEVEL FLOW..A LOCALIZED SEVERE THREAT WILL EXIST IN STRONGER CELLS...WITH RELATIVELY WEAK DESTABILIZATION THE PRIMARY LIMITING FACTOR TO CONVECTIVE POTENTIAL. IT APPEARS THAT THE BEST POTENTIAL FOR SEVERE STORMS MAY BE FROM PARTS OF NORTHEAST NEVADA/EXTREME NORTHWEST UTAH INTO SOUTHWESTERN IDAHO...WHERE LOW-LEVEL MOISTURE TRANSPORT IS FOCUSED BENEATH NORTHEASTERN FRINGE OF MID-LEVEL DRY SLOT. THOUGH MID-LEVEL FORCING FOR UPWARD VERTICAL MOTION IS UNCERTAIN...DIFLUENCE ALOFT MAY ENHANCE STORM DEVELOPMENT. AND...WITH MIXED LAYER CAPE POSSIBLY AS HIGH AS 500-1000 J/KG...HODOGRAPHS ARE SUFFICIENT FOR ISOLATED SUPERCELLS THROUGH EARLY EVENING. ...TENNESSEE VALLEY INTO MID ATLANTIC STATES... MOIST AIR MASS ALONG STALLED FRONTAL ZONE HAS HEATED AND BECOME WEAK TO LOCALLY MODERATELY UNSTABLE...SUPPORTIVE OF CONVECTIVE DEVELOPMENT. FAVORABLE OROGRAPHY ALONG THE SOUTHERN/CENTRAL APPALACHIANS IS SUPPORTING ADDITIONAL ACTIVITY...WHICH LIKELY WILL INCREASE FURTHER LATE THIS AFTERNOON. WELL TO THE SOUTHEAST OF A SHORT WAVE TROUGH DIGGING ACROSS THE GREAT LAKES REGION...FLOW FIELDS/SHEAR ARE WEAK...BUT UNSATURATED THERMODYNAMIC PROFILES COULD CONTRIBUTE TO ISOLATED DOWNBURSTS IN STRONGER STORMS THROUGH EARLY EVENING. SCATTERED STORMS MAY PERSIST ALONG FRONT AS IT PRESSES SOUTHEAST OF THE CENTRAL/SOUTHERN APPALACHIANS LATER TONIGHT...WITH CONTINUED SOUTHEASTWARD PROGRESSION OF UPSTREAM TROUGH. ..KERR.. 10/05/2006  From swody1 at goshenarc.org Fri Oct 6 00:59:19 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 05 Oct 2006 20:59:19 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060058 SWODY1 SPC AC 060057 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0757 PM CDT THU OCT 05 2006 VALID 060100Z - 061200Z ...NO SVR TSTM AREAS FORECAST... ...SOUTHWEST TO GREAT BASIN... SATELLITE IMAGERY DEPICTS EXTENSIVE BAROCLINIC LEAF LAYERED CLOUD PATTERN FROM THE BAJA NNEWD ACROSS AZ...UT...WRN CO...AND ID/WY. THIS ZONE OF STRONG ASCENT EXISTS TO THE EAST OF A SLOW MOVING LARGE SCALE UPPER LOW DROPPING SLOWLY SSEWD OVER THE CNTRL CA COAST. EXTENSIVE MOISTURE PLUME AND DYNAMIC LIFT AHEAD OF THE TROUGH WILL CONTINUE TO RESULT IN SUFFICIENT INSTABILITY TO MAINTAIN WIDESPREAD CONVECTION TONIGHT FROM PARTS OF AZ NWD ACROSS THE GREAT BASIN AND WRN SLOPES OF THE ROCKIES. WITH MUCAPE VALUES STRUGGLING TO CLIMB MUCH ABOVE ABOUT 500 J/KG...UPDRAFTS WILL REMAIN RELATIVELY WEAK AND INCREASINGLY DECOUPLED FROM SURFACE LAYER. DESPITE THESE LIMITATIONS...EXTENSIVE NATURE OF CONVECTION AND VERY STRONG SHEAR SUGGEST THE POSSIBILITY OF ONE OR TWO WIND OR HAIL EVENTS AS SMALLER SCALE IMPULSES PIVOT AROUND THE LARGE SCALE TROUGH AND ENHANCE FORCED ASCENT IN MOIST WEAKLY UNSTABLE REGIME. ...CNTRL APPALACHIANS... SCATTERED DISORGANIZED STORMS PERSIST ACROSS THE CUMBERLAND PLATEAU LATE THIS EVENING AS A COLD FRONT MOVES TOWARD THE CNTRL APPALACHIANS. MODEL FORECASTS SUGGEST THAT CONVECTION SHOULD PERSIST IN WEAKLY UNSTABLE AIR MASS FROM THE APPALACHIANS EWD ACROSS VA/NC TONIGHT AS UPWARD VERTICAL MOTION INTENSIFIES WITH THE APPROACH OF A STRONG SHORT WAVE TROUGH. AS SHEAR AND FORCING FOR ASCENT STRENGTHEN THROUGH THE NIGHT...A FEW STRONG TO ISOLATED SEVERE STORMS WITH HAIL AND/OR WIND APPEAR POSSIBLE. THUS...THIS FORECAST WILL MAINTAIN A RELATIVELY SMALL LOW PROBABILITY SEVERE AREA FROM ONGOING ACTIVITY OVER ERN TN...EWD ACROSS SWRN VA/NRN NC. ..CARBIN.. 10/06/2006  From swody1 at goshenarc.org Fri Oct 6 05:33:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 06 Oct 2006 01:33:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 060532 SWODY1 SPC AC 060531 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1231 AM CDT FRI OCT 06 2006 VALID 061200Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER ERN NV...MUCH OF AZ AND UT... ...SYNOPSIS... LARGE SCALE OMEGA BLOCK PATTERN WILL CONTINUE ACROSS THE LOWER 48 STATES THIS PERIOD WITH STRONG TROUGHS ALONG EACH COAST...AND A LARGE SCALE RIDGE DOMINATING THE CNTRL U.S. FROM TX TO THE GREAT LAKES. A SIGNIFICANT SHORT WAVE IMPULSE ACCOMPANIED BY 70KT MID LEVEL FLOW WILL EJECT FROM THE BASE OF THE DEEP WEST COAST TROUGH AND MOVE FROM THE LOWER CO RIVER VALLEY...NEWD ACROSS THE GREAT BASIN...AND THEN OVER THE NRN ROCKIES THROUGH EARLY SATURDAY. DOWNSTREAM FROM THE CNTRL STATES UPPER RIDGE...A VIGOROUS SHORT WAVE TROUGH...CURRENTLY CROSSING THE OH VALLEY...WILL DIG SSEWD ACROSS THE CAROLINAS WHILE EVOLVING INTO A COMPACT COLD CORE VORTEX OVER NC THROUGH LATE TODAY. ...SOUTHWEST/GREAT BASIN... STRONG DEEP LAYER SLY FLOW CONTINUES TO TRANSPORT ABUNDANT MOISTURE NWD AHEAD OF THE STRONG SLOW MOVING UPPER LOW OVER CA. LOW LEVELS HAVE ALSO MOISTENED THROUGH A COMBINATION OF ADVECTION AND DIABATIC EFFECTS. WHILE FORCING FOR ASCENT IS EXPECTED TO INCREASES FURTHER TODAY WITH THE NEWD ACCELERATION OF SHORT WAVE IMPULSE OUT OF SRN CA...OVERALL DESTABILIZATION WILL PROBABLY REMAIN MARGINAL GIVEN POTENTIAL FOR WIDESPREAD CLOUDINESS AND PRECIPITATION. HOWEVER...RELATIVELY STEEP LAPSE RATES MAINTAINED BY ADIABATIC COOLING/STRONG ASCENT SHOULD CONTRIBUTE TO CAPE ON THE ORDER OF 200-500 J/KG WHICH WILL ADEQUATELY FUEL RELATIVELY LOW-TOPPED CONVECTION. GIVEN THE PRESENCE OF VERY STRONG EFFECTIVE SHEAR...AND FOCUSED FORCING ON THE NOSE OF 70 KT MID LEVEL JET STREAK SPREADING ACROSS SRN NV/WRN AZ THROUGH THE AFTERNOON... EXPECT AN INCREASE IN SEVERE STORM POTENTIAL. FAST-MOVING LINES/BANDS OF STORMS AND A FEW SUPERCELLS APPEAR POSSIBLE AS THE STRONG ASCENT ACCOMPANYING THE MID LEVEL IMPULSE ACTS ON MOIST/UNSTABLE AIR MASS. IN ADDITION TO HAIL AND HIGH WINDS...AN ISOLATED TORNADO CANNOT BE RULED OUT. ORGANIZED ACTIVITY AND SEVERE THREAT SHOULD SPREAD NEWD FROM ERN NV/AZ AND INTO UT THROUGH LATE AFTERNOON/EVENING. ...MID ATLANTIC/SOUTHEAST COASTS... SURFACE FRONT SHOULD STRENGTHEN AND SURGE SEWD INTO WARM/MOIST AIR MASS ALONG THE COASTAL PLAIN AS VIGOROUS MID LEVEL CYCLOGENESIS COMMENCES OVER SRN VA/NC THIS AFTERNOON. WHILE STRONGER DEEP SHEAR IS FORECAST TO LAG THE FRONTAL LIFT...INCREASINGLY STRONG FORCING ACROSS THE REGION COULD AID TSTM DEVELOPMENT ALONG THE FRONT AS IT MOVES EAST. A COUPLE OF SEVERE STORMS WITH STRONG TO DAMAGING WINDS APPEAR POSSIBLE OVER A RELATIVELY SMALL REGION. ISOLATED AND MARGINALLY SEVERE HAIL MAY ALSO OCCUR BENEATH THE DEVELOPING MID LEVEL LOW CENTER OVER ERN NC THROUGH EVENING. ...NRN ROCKIES TO NRN PLAINS... CONVECTION IS FORECAST TO INCREASE IN A SW-NE BAND FROM NRN NV ACROSS ID...AND INTO PARTS OF MT...FROM LATE AFTERNOON INTO THE NIGHT AS STRENGTHENING MID LEVEL DEFORMATION ZONE ACTS ON NWRN PERIPHERY OF DEEP MOISTURE PLUME. INSTABILITY AND SHEAR ARE EXPECTED TO REMAIN MARGINAL WITHIN THIS AXIS...BUT LAPSE RATES AND FORCING APPEAR SUFFICIENT FOR A COUPLE OF HAIL STORMS OVER THE NRN ROCKIES. LOW-AMPLITUDE SHORT WAVE IMPULSE AND INCREASING LOW LEVEL SLY FLOW MAY COMBINE TO PRODUCE A FEW ELEVATED STORMS ACROSS THE WRN DAKOTAS THROUGH EARLY SATURDAY. A LOW PROBABILITY OF HAIL WILL EXIST WITH THIS ACTIVITY. ..CARBIN/EVANS.. 10/06/2006  From swody1 at goshenarc.org Sat Oct 7 00:49:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 06 Oct 2006 20:49:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 070052 SWODY1 SPC AC 070051 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT FRI OCT 06 2006 VALID 070100Z - 071200Z ...THERE IS A SLGT RISK OF SVR TSTMS SERN NV/SRN UT... ...SRN GREAT BASIN... SATELLITE IMAGERY AND SHORT-TERM MODEL DATA DEPICTED AN INTENSE MID LEVEL VORTICITY MAX ASSOCIATED WITH AN 80KT JET STREAK CURRENTLY EJECTING NEWD FROM THE BASE OF A DEEP TROUGH ACROSS CA AND THE LOWER CO RIVER VALLEY. STRONG LIFT ACCOMPANYING THIS IMPULSE WAS ACTING ON A MOIST AND WEAKLY UNSTABLE AIR MASS FROM SERN NV ACROSS SRN UT THIS EVENING. RESULTING FAST-MOVING BANDS AND CLUSTERS OF SCATTERED LOW-TOPPED STORMS SHOULD CONTINUE TO SPREAD NEWD AND EWD FROM ERN NV TO SRN UT THROUGH TONIGHT. WHILE MEAGER INSTABILITY WILL TEMPER A MORE WIDESPREAD SEVERE THREAT WITH THIS CONVECTION...MAGNITUDE OF FORCING AND SHEAR WILL REMAIN SUFFICIENT FOR POSSIBLE HAIL/WIND EVENTS FROM SOME OF THE STRONGER/MORE PERSISTENT UPDRAFTS. ...SOUTHEAST... TIGHTLY WOUND MID LEVEL CYCLONE CONTINUES TO EVOLVE NEAR THE VA/NC BORDER AREA TONIGHT. BULK OF DEEP CONVECTION ASSOCIATED WITH THIS SYSTEM HAS MOVED OFFSHORE WITH THE STRONG FRONTAL SURGE ARCING FROM THE NC/VA CAPES TO THE GA COAST. VERY STRONG FORCING AND LOW STATIC STABILITY MAY CONTINUE TO CONTRIBUTE TO A MAUL LAYER ACROSS INLAND PORTIONS OF NERN NC AND SERN VA WHERE ISOLATED STRONG UPDRAFTS COULD STILL PRODUCE SMALL HAIL TONIGHT. FARTHER SOUTH...FRONTAL LIFT CONTINUES TO SPAWN A FEW INTENSE STORMS OFF THE SC COAST...WWD/INLAND TO WEST OF SAV. RECENT TRENDS IN RADAR REFLECTIVITY SUGGEST AREAL EXTENT OF SEVERE POTENTIAL WITH THIS ACTIVITY SHOULD CONTINUE TO DIMINISH. ..CARBIN.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 12:17:37 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 08:17:37 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071220 SWODY1 SPC AC 071218 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0718 AM CDT SAT OCT 07 2006 VALID 071300Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... THE HIGH AMPLITUDE MID/UPPER LEVEL FLOW PATTERN PERSISTS ACROSS THE CONUS WITH LARGE RIDGE CENTRAL U.S FLANKED NEAR BOTH COASTS BY TROUGHS. IN THE WRN U.S. CURRENTLY A STRONG IMPULSE EJECTING FROM WRN TROUGH AND WILL PHASE WITH NRN STREAM SUPPORTING A DEEPENING SURFACE LOW SERN MT MOVING QUICKLY INTO WESTERN ONTARIO TONIGHT. WESTERN TROUGH THEN REFORMS AN UPPER LOW THAT DROPS SWD INTO SRN CA TONIGHT. THE STILL INTENSIFYING UPPER LOW NEAR THE NC/VA BORDER PROGGED TO CONTINUE SSWWD INTO SERN GA TONIGHT. CURRENT ASSOCIATED SURFACE LOW NEAR COASTAL BORDER VA/NC WILL GRADUALLY FILL AS COLD FRONT PUSHES FURTHER OFFSHORE. ...SWRN U.S... DRIER SWLY FLOW HAS SPREAD ACROSS MUCH OF AZ IN THE WAKE OF S/WV THAT EJECTED FRIDAY ACROSS INTERMOUNTAIN REGION. MOIST SUBTROPICAL PLUME PERSISTS ACROSS NWRN MEXICO EXTREME ERN AZ AND NM. AS UPPER LOW REDEVELOPS SRN CA...PREVAILING FLOW WILL GRADUALLY BACK TO MORE SLY BY TONIGHT WITH MOISTURE AGAIN INCREASING BACK INTO AZ. SHEAR PROFILES HAVE WEAKENED WITHIN THE MOIST PLUME TODAY AND WITH ONLY LIMITED HEATING...INSTABILITY SHOULD GENERALLY REMAIN LESS THAN 1000 J/KG. SCTD THUNDERSTORMS SHOULD DEVELOP BY AFTERNOON NEAR HIGHER TERRAIN WITH POTENTIAL FOR ISOLATED MARGINAL WIND/HAIL EVENTS. THUNDERSTORMS WILL LIKELY CONTINUE AFTER DARK AND POSSIBLY SPREAD FURTHER W INTO AZ AS BACKING FLOW TONIGHT BRINGS MOISTURE INTO CENTRAL AZ. ...MID ATLANTIC COAST... STRONG LOW LEVEL ONSHORE FLOW SERN VA SHOULD SLOWLY WEAKEN AS UPPER LOW CONTINUES TO DRIFT SSWWD AND COOLER MORE STABLE AIR MASS MOVES TO THE COAST. ISOLATED SEVERE WILL STILL BE POSSIBLE THIS AM GIVEN THE STRONG SHEAR AND MARGINAL INSTABILITY. THESE CONDITIONS SHOULD WORK SWD ALONG NRN NC COAST DURING THE DAY AND GRADUALLY DIMINISH. ..HALES/GRAMS.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 16:27:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 12:27:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071630 SWODY1 SPC AC 071629 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1129 AM CDT SAT OCT 07 2006 VALID 071630Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... DEEP NC UPR LOW EXPECTED TO CONTINUE SSW TROUGH SUNDAY AS HIGH AMPLITUDE RIDGE PERSISTS OVER THE MS VLY AND MAIN PORTION OF WRN STATES TROUGH LIFTS NE INTO S CNTRL CANADA. AT LWR LEVELS...SURFACE TROUGH ASSOCIATED WITH NC LOW SHOULD REDEVELOP S ACROSS FAR ERN NC/SC THROUGH THE PERIOD...WHILE LOW ASSOCIATED WITH WRN TROUGH LIFTS RAPIDLY NE ACROSS ND INTO WRN ONTARIO. ...TIDEWATER VA S INTO FAR ERN NC/OUTER BANKS... UNUSUAL PATTERN WITH SSW-MOVING NOR'EASTER. SURFACE AND SATELLITE DATA SHOW AREA OF MODIFIED TROPICAL AIR MASS /EFFECTIVE WARM SECTOR/ EXTENDING FROM OFF THE SE VA/NC CST WWD IN A NARROWING WEDGE INTO EXTREME SE VA NEAR ORF. SSW MOTION OF UPR SYSTEM AND ASSOCIATED BAND OF DEEP ELY FLOW TO ITS NORTH SUGGEST THAT THE WARM SECTOR WILL REDEVELOP SSW WITH TIME AS SHALLOW BOUNDARY THAT MOVED JUST OFF THE NC CST LATE YESTERDAY RETROGRESSES W. WHILE LITTLE SURFACE DEVELOPMENT IS EXPECTED THROUGH THE PERIOD... ONSHORE MOVEMENT OF NARROW WARM SECTOR AND ASSOCIATED LOW LEVEL CONVERGENCE/ENHANCED WIND SHEAR FIELDS MAY BE SUFFICIENT TO SUPPORT A BAND OR TWO OF THUNDERSTORMS WITH LOW LEVEL ROTATION. IF THE GUIDANCE IS TO BE BELIEVED REGARDING FCST SSW WOBBLING OF UPR COLD POCKET...WARM SECTOR INSTABILITY SHOULD GRADUALLY DIMINISH THROUGH THE PERIOD AFTER SOME TEMPORARY DESTABILIZATION FROM SURFACE HEATING OVER EXTREME ERN NC TODAY. IF INSTABILITY/CONVERGENCE DO NEVERTHELESS PROVE SUFFICIENT TO SUPPORT SUSTAINED SURFACE-BASED STORMS IN WARM SECTOR...A LOW PROBABILITY THREAT WILL EXIST FOR BRIEF TORNADOES. THIS THREAT SHOULD MOVE SWD FROM TIDEWATER VA/FAR NE NC EARLY THIS AFTN TO THE HATTERAS AREA LATER TODAY/TONIGHT...TO POSSIBLY THE MHX/ILM AREA EARLY SUNDAY. ...SW U.S... DRIER SW FLOW HAS OVERSPREAD MUCH OF AZ IN THE WAKE OF SHORTWAVE TROUGH NOW LIFTING NE ACROSS WY/MT. SUBTROPICAL MOISTURE PLUME WILL...HOWEVER...PERSIST FROM NE SONORA INTO EXTREME ERN AZ AND NM. AS UPR TROUGH LINGERS IN THE WEST AND A LOW REDEVELOPS ALONG THE SRN CA CST...DEEP FLOW WILL SLOWLY BACK TO A MORE SLY COMPONENT...ALLOWING MOISTURE TO ONCE AGAIN INCREASE ACROSS CNTRL AZ THIS EVENING. SHEAR PROFILES HAVE WEAKENED WITHIN THE MOIST PLUME RELATIVE TO YESTERDAY...BUT HEATING SHOULD BOOST SBCAPE TO AROUND 1000 J/KG. SCTD THUNDERSTORMS SHOULD STRENGTHEN/DEVELOP BY AFTN INVOF HIGHER TERRAIN IN ERN AZ/NM AND FAR SW AZ...WITH POTENTIAL FOR ISOLATED MARGINALLY SEVERE WIND/HAIL. SOME OF THIS ACTIVITY COULD CONTINUE INTO TONIGHT AND MAY SPREAD FARTHER W INTO AZ AS UPR FLOW BACKS. ...CNTRL PLNS... SURFACE HEATING AND CONVERGENCE/WARM ADVECTION ALONG ENHANCED LEE TROUGH TRAILING SW FROM ND LOW MAY YIELD A FEW STORMS WITH GUSTY WINDS IN PARTS OF NEB/NE CO AND SE SD LATER TODAY INTO TONIGHT. ..CORFIDI/BOTHWELL.. 10/07/2006  From swody1 at goshenarc.org Sat Oct 7 19:48:01 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 15:48:01 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 071951 SWODY1 SPC AC 071949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SAT OCT 07 2006 VALID 072000Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...TIDEWATER VA S INTO FAR ERN NC/OUTER BANKS... CLOSED UPPER LOW WILL CONTINUE TO MOVE SSWWD INTO SC THIS FORECAST PERIOD...REACHING SRN SC/GA COAST REGION BY 12Z SUNDAY. STRONGER MID LEVEL FLOW IS EXPECTED TO REMAIN ALONG THE WRN/SRN PERIPHERIES OF THIS SYSTEM. IN THE LOW LEVELS...SMALL WARM SECTOR WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S EXTENDED INLAND FROM FAR SERN VA S TO EAST CENTRAL NC. AS THE CLOSED LOW MOVES TO THE SSW...ATTENDANT MOIST/WARM SECTOR SHOULD ALSO REDEVELOP TO THE SSW ALONG AND JUST INLAND OF THE NC COAST. OBJECTIVE ANALYSES INDICATED STRONGER INSTABILITY WAS LOCATED OFFSHORE...WHILE WEAK MID LEVEL LAPSE RATES AND LARGE SCALE SUBSIDENCE IN WAKE OF UPPER LOW WERE TENDING TO LIMIT DEVELOPMENT OF DEEP MOIST CONVECTION WITHIN INLAND WARM SECTOR. NARROW AXIS OF CONVECTION SHOULD CONTINUE INTO THE EVENING ALONG WARM CONVEYOR BELT EXTENDING INTO NERN NC/SERN VA. POTENTIAL FOR A BRIEF TORNADO WILL PERSIST FOR THE NEXT FEW HOURS...PRIOR TO LOSS OF DAYTIME HEATING...AS GREATER SURFACE VORTICITY AND LOW LCLS EXIST ALONG THIS NARROW CONVERGENCE BAND. THIS THREAT MAY DEVELOP SWD ALONG NC COAST TONIGHT AS ASSOCIATED CONVERGENCE BAND MOVES S. ...SERN AZ/WRN-SRN NM... NARROW AXIS OF SURFACE DEWPOINTS IN THE MID-UPPER 50S LOCATED OVER SERN AZ/SWRN NM COMBINED WITH ADDITIONAL SURFACE HEATING SUGGESTS THE AIR MASS SHOULD REMAIN MARGINALLY TO MODERATELY UNSTABLE /MLCAPE 500-1000 J/KG/ INTO THE EARLY EVENING. ALTHOUGH MID-UPPER LEVEL FLOW REGIME IS SOMEWHAT FLAT ACROSS THIS REGION...WATER VAPOR IMAGERY INDICATED THAT A WEAK SUB-TROPICAL IMPULSE MAY BE TRAVERSING NRN MEXICO INTO SWRN NM AT THIS TIME...AIDING IN ONGOING CONVECTION. WEAK DEEP LAYER SHEAR IS EXPECTED TO LIMIT SEVERE THREAT...BUT A FEW OF THE STRONGER STORMS MAY BECOME CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL AND/OR WIND GUSTS. ...CNTRL PLNS... SURFACE HEATING AND CONVERGENCE/WARM ADVECTION ALONG ENHANCED LEE TROUGH TRAILING SW FROM ND LOW MAY YIELD A FEW STORMS WITH GUSTY WINDS IN PARTS OF NEB/NE CO AND SE SD LATER TODAY INTO TONIGHT. ..PETERS.. 10/07/2006  From swody1 at goshenarc.org Sun Oct 8 00:28:28 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 07 Oct 2006 20:28:28 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080030 SWODY1 SPC AC 080029 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0729 PM CDT SAT OCT 07 2006 VALID 080100Z - 081200Z ...NO SVR TSTM AREAS FORECAST... ...SOUTHWEST... WEAK PERTURBATIONS EMBEDDED WITHIN DEEP LAYER SWLY FLOW AND MOISTURE PLUME AHEAD OF STRONG SRN CA TROUGH CONTINUE TO AID DEEP CONVECTION FROM WRN MEXICO TO NM/CO AND THE EXTREME WRN TX PNHDL THIS EVENING. MUCH OF THIS ACTIVITY EXISTS TO THE EAST OF A BAND OF STRONGER FLOW ALOFT AND GENERALLY DISORGANIZED NATURE OF THE CONVECTION AND LIMITED CAPE SHOULD PRECLUDE SEVERE POTENTIAL OVERNIGHT. ...SOUTHEAST... DEEP MID LEVEL LOW CONTINUES TO DROP SOUTH ACROSS THE CAROLINAS TONIGHT WHILE PRIMARY SURFACE LOW WITH THIS SYSTEM REMAINS OFF THE OUTER BANKS. MOIST ONSHORE FLOW ACROSS ERN NC BENEATH MID LEVEL DRY SLOT DID ALLOW FOR WEAK DESTABILIZATION AND A FEW STORMS PERSIST IN THIS REGION WITHIN MODEST WARM CONVEYOR BELT. WITH THE MID/UPPER LOW MOVING AWAY FROM THE REGION AND BEGINNING TO FILL...AND DIURNAL STABILIZATION SETTING IN...THE CHANCE FOR A SEVERE STORM APPEARS TO BE DECREASING. OVER FL...WIND SHIFT/FRONT ASSOCIATED WITH THE ANOMALOUS SYSTEM OVER THE CAROLINAS HAS INTERSECTED EAST COAST SEA-BREEZE BOUNDARY AND RESULTED IN ROBUST TSTM DEVELOPMENT IN WARM MOIST AIR MASS. SUPERCELL MOVING ACROSS ORANGE COUNTY HAS RECENTLY PRODUCED MARGINALLY SEVERE HAIL. ANOTHER HAIL OR WIND REPORT REMAINS POSSIBLE WITH THIS ACTIVITY OVER THE NEXT HALF-HOUR OR SO BUT OVERALL TREND SHOULD BE ONE OF WEAKENING WITH THE LOSS OF DAYTIME HEATING AND LACK OF MORE PRONOUNCED FORCING. ...NRN AND CNTRL PLAINS... HIGH-BASED CONVECTION HAS RECENTLY DEVELOPED ALONG PRE-FRONTAL TROUGH SITUATED ACROSS NCNTRL NEB. ADDITIONAL MESOSCALE FORCING WILL MOVE ACROSS THE REGION TONIGHT AS STRONG COLD FRONT SWEEPS SEWD FROM THE NRN HIGH PLAINS. WELL MIXED AND DRY BOUNDARY LAYER AIR MASS COULD SUPPORT GUSTY DOWNDRAFTS WITH AN ISOLATED STORM OR TWO OVER THE NEXT HOUR BUT LIMITED MOISTURE AND DECOUPLING SHOULD TEMPER MORE WIDESPREAD CONVECTIVE POTENTIAL OVERNIGHT. ..CARBIN.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 04:33:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 00:33:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 080436 SWODY1 SPC AC 080434 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1134 PM CDT SAT OCT 07 2006 VALID 081200Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS SERN AZ AND WRN NM... ...SYNOPSIS... MORE OF A SPLIT FLOW REGIME WILL DEVELOP ACROSS NRN/CNTRL U.S THIS PERIOD AS NRN STREAM REMAINS QUITE PROGRESSIVE...AND SRN STREAM RETAINS SOME AMPLITUDE. STRONGEST HEIGHT FALLS WITH THE NRN STREAM SHORT WAVE TROUGH NOW CROSSING NRN PLAINS WILL SPREAD EAST ACROSS SRN CANADA. HOWEVER...WEAK HEIGHT FALLS ASSOCIATED WITH THIS FEATURE WILL ACT TO DAMPEN THE UPPER RIDGE AXIS FROM THE GREAT LAKES TO THE NORTHEAST. A BROAD BELT OF DEEP LAYER SWLY FLOW WILL PERSIST IN THE WAKE OF THE NRN STREAM IMPULSE...FROM THE SOUTHWEST TO THE UPPER MS VALLEY/GREAT LAKES. AS STRONGER FORCING PULLS AWAY FROM THE PLAINS... ASSOCIATED TRAILING COLD FRONT WILL BE ALIGNED WITH THE DEEP LAYER SWLY FLOW. THEREFORE THE FRONT WILL MAKE ONLY GRADUAL EWD/SEWD PROGRESS ACROSS THE UPPER MS AND MO VALLEYS THIS PERIOD... AND SHOULD EXTEND FROM LOWER MI TO KS BY EARLY MONDAY. HIGH PLAINS SEGMENT OF THE COLD FRONT IS FORECAST TO SURGE SWD FROM ERN CO AND ACROSS THE TX PNHDL TODAY AND TONIGHT WITH LIFT ACROSS THIS BOUNDARY LIKELY BEING ENHANCED BY A LOW AMPLITUDE IMPULSE EMANATING OUT OF THE SRN STREAM. UPPER LOW ACROSS SRN CA WILL BEGIN TO BE SHUNTED EWD ACROSS THE LOWER CO RIVER VALLEY THROUGH THIS PERIOD AS A NRN STREAM DISTURBANCE SPREADS SEWD ACROSS THE INTERIOR NORTHWEST. OTHER SRN STREAM CLOSED LOW...OVER THE SOUTHEAST...WILL CONTINUE TO FILL AND DRIFT ACROSS THE GA/NRN FL COASTLINE LATER THIS AFTERNOON. ...AZ/NM... DYNAMIC FORCING FOR ASCENT ASSOCIATED WITH THE SRN CA UPPER LOW WILL SPREAD EAST ATOP A RELATIVELY MOIST AND INCREASINGLY UNSTABLE AIR MASS ACROSS PARTS OF SERN AZ THIS AFTERNOON. MODEL GUIDANCE INDICATES STRONG CONVECTION WILL DEVELOP AS THE LIFT ASSOCIATED WITH THE TROUGH COMBINES WITH DIURNAL HEATING AND UPSLOPE FLOW. DEEP LAYER SHEAR IS ALSO EXPECTED TO STRENGTHEN COINCIDENT WITH TSTM DEVELOPMENT AND SHOULD SUPPORT STORM ORGANIZATION. LINES OR CLUSTERS OF STORMS AND PERHAPS A FEW SUPERCELLS APPEAR POSSIBLE AND COULD BE ACCOMPANIED BY HAIL AND LOCALLY HIGH WINDS FROM SERN AZ EWD/NEWD INTO PORTIONS OF WRN NM. ...SRN HIGH PLAINS... ANOTHER AREA OF DEEP CONVECTION MAY EVOLVE AS A LOW AMPLITUDE MID/UPPER WAVE DEVELOPS NNEWD FROM SRN/CNTRL NM ACROSS SERN CO AND THE TX/OK PNHDLS LATER TODAY. THIS FEATURE IS EMBEDDED WITHIN TROPICAL MOISTURE CONNECTION BUT LIMITED LOW LEVEL MOISTURE AND POTENTIAL FOR ABUNDANT CLOUD COVER ACROSS THE SRN HIGH PLAINS MAY LIMIT GREATER SURFACE-BASED DESTABILIZATION. IF HEATING AND WEAK DESTABILIZATION CAN OCCUR AHEAD OF THE FRONTAL SURGE DEVELOPING ACROSS THESE AREAS LATER TODAY...LIFT AND SHEAR APPEAR ADEQUATE FOR A COUPLE OF SEVERE STORMS. ANY SURFACE-BASED ACTIVITY MAY BE QUICKLY UNDERCUT BY THE COLD FRONT BUT COULD STILL POSE A THREAT OF MARGINALLY SEVERE HAIL. GIVEN UPPER FORCING AND LIFT ACROSS THE ADVANCING FRONT...A SMALL MCS MAY EVOLVE FROM THE INITIAL ACTIVITY AND DEVELOP EAST ACROSS THE TX PNHDL THROUGH SUNDAY NIGHT. MARGINAL HAIL AND GUSTY WINDS MAY ACCOMPANY THIS SYSTEM BUT AREAL EXTENT OF SEVERE POTENTIAL AND LEVEL OF UNCERTAINTY AT THIS TIME DO NOT WARRANT HIGHER SEVERE PROBABILITIES. ...SOUTHEAST COAST/FL... MOIST ONSHORE FLOW ACROSS ERN CAROLINAS BENEATH COLD POOL AND LIFT ASSOCIATED WITH MID/UPPER LEVEL LOW MAY BE ENOUGH FOR A COUPLE OF TSTMS. INSTABILITY...HOWEVER...WILL LIKELY BE WEAK AND LITTLE SEVERE THREAT IS CURRENTLY ANTICIPATED. FURTHER SOUTH...OVER FL...GREATER SURFACE-BASED INSTABILITY MAY DEVELOP ACROSS THE ECNTRL PART OF THE PENINSULA. FORCING AND STEEPER LAPSE RATES ASSOCIATED WITH THE UPPER SYSTEM WILL BRUSH THE EAST COAST AS SEA-BREEZE CONVECTIVE DEVELOPMENT OCCURS DURING THE AFTERNOON. PRIOR NAM-WRF FORECASTS WERE VERY ACCURATE IN DEPICTING THE ISOLATED DEVELOPMENT THAT OCCURRED SATURDAY EVENING. LATEST NAM-WRF SUGGESTS A SIMILAR ENVIRONMENT AND SCENARIO APPEAR POSSIBLE SUNDAY AFTERNOON AND EVENING. THUS...LOW SEVERE PROBABILITIES FOR WIND/HAIL...AND AN ISOLATED TORNADO...WILL BE INTRODUCED FOR PARTS OF ERN FL TODAY. ..CARBIN/GRAMS.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 12:33:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 08:33:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081236 SWODY1 SPC AC 081235 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0735 AM CDT SUN OCT 08 2006 VALID 081300Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF AZ AND WRN NM... ...SYNOPSIS... MS VLY RIDGE WILL DEAMPLIFY THIS PERIOD AS SHORTWAVE TROUGH THAT CROSSED THE RCKYS YESTERDAY CONTINUES ENE ACROSS THE UPR GRT LKS/SRN ONTARIO...AND AN UPSTREAM IMPULSE NOW OVER VANCOUVER ISLAND AMPLIFIES SE INTO THE PAC NW. PATTERN CHANGE WILL ALLOW CLOSED SYSTEM THAT DEVELOPED OVER SRN CA ON SATURDAY TO LINGER OVER THAT REGION FOR ANOTHER 24 HRS. FARTHER E...WEAKENING OF MS VLY RIDGE WILL ALSO PROMOTE A MODEST INCREASE IN WLY FLOW ACROSS THE SERN U.S...AND SHOULD FORCE ANOMALOUS SYSTEM STILL DRIFTING S/SW ACROSS SC TO TURN MORE E AND OFF THE GA CST EARLY MONDAY. ...ERN CAROLINAS... A SYNOPTIC SETUP SIMILAR TO SATURDAY'S BUT DISPLACED FARTHER SW WILL PREVAIL OVER THE SERN STATES TODAY AS DEEP CLOSED LOW CONTINUES TO WOBBLE SSW ACROSS SC/ERN GA. WRN PART OF SYSTEM WARM SECTOR SHOULD CONTINUE TO REDEVELOP SW ACROSS THE SRN NC AND ERN SC CSTL PLN TODAY BEFORE UPR SYSTEM BEGINS TO TURN MORE ELY OVER GA THIS EVENING. WIDELY SCATTERED TRANSIENT ROTATING STORMS/WEAK SUPERCELLS PERSISTED DURING THE OVERNIGHT INVOF SLOW WWD-MOVING BOUNDARY JUST OFF THE NC CST...AND BANDS OF SLIGHTLY ELEVATED STORMS REGENERATED THROUGH THE NIGHT A BIT FARTHER W INTO THE SRN NC/ERN SC SANDHILLS/PIEDMONT. SURFACE HEATING LIKELY WILL ALTER THIS NOCTURNAL CONVECTIVE PATTERN TODAY...BUT OVERALL SETUP SHOULD REMAIN FAVORABLE FOR ISOLATED TORNADOES AND POSSIBLE WATERPSOUTS WITH ANY LONGER-LIVED/MORE DISCRETE STORMS NEAR THE CST. ...CNTRL/SRN FL PENINSULA... BAND OF ENHANCED /40+ KT/ WLY MID LEVEL FLOW ON SRN FRINGE OF SC/GA LOW WILL OVERSPREAD CNTRL FL TODAY. WEAK CONVERGENCE SHOULD PERSIST INVOF SLOWLY MOVING COLD FRONT NOW EXTENDING FROM NEAR SRQ TO NEAR VRB. RELATIVELY WEAK...MAINLY WLY LOW LEVEL WINDS SHOULD FAVOR CONVERGENCE/DIURNAL STORM DEVELOPMENT ON E CST SEA BREEZE FRONT...ESPECIALLY NEAR INTERSECTION WITH SYNOPTIC COLD FRONT. ACTIVITY MAY BE SLOW TO DEVELOP GIVEN MODEST MID LEVEL LAPSE RATES. BUT ONCE STARTED...HI PWS AND STRENGTHENING FLOW ALOFT SUGGEST POTENTIAL FOR HIGH WIND BEFORE STORMS MOVE OFFSHORE EARLY TONIGHT. ...AZ/WRN NM... HIGHER CLOUDS OF EARLIER SUBTROPICAL PLUME ARE LIFTING NEWD OUT OF AZ ATTM...SUGGESTING THAT FAIRLY STRONG HEATING WILL OCCUR TODAY ALONG WRN EDGE OF LOW LEVEL MOISTURE AXIS. GOES/GPS PW DATA SHOW MOISTURE COVERING ROUGHLY THE SERN THIRD OF THE STATE...AND MOISTURE MAY SPREAD A BIT FARTHER W WITH TIME AS CA UPR LOW EDGES ONLY SLOWLY E TOWARD THE LWR CO VLY ...ALLOWING MORE SUBSTANTIAL MOISTURE TO SPREAD N FROM SONORA. COUPLED WITH STEEP LOW TO MID LEVEL LAPSE RATES AND MODERATE /30 KT/ SSWLY FLOW...SETUP COULD YIELD CLUSTERS/BANDS OF STRONG TO SEVERE STORMS WITH HIGH WIND AND POSSIBLY MARGINALLY SEVERE HAIL. ...SRN HI PLNS... SATELLITE AND MODEL FCSTS SUGGEST THAT A WEAK IMPULSE WILL LIFT NNE ACROSS NM TODAY...WHERE CLOUD COVER WILL BE SUBSTANTIAL. BUT MODERATE BOUNDARY LAYER MOISTURE IS IN PLACE...AND WEAKLY CONVERGENT UPSLOPE FLOW WILL PREVAIL OVER THE ERN NM HI PLNS E/NE INTO W TX AND THE TX PANHANDLE. THIS SETUP MAY SUPPORT DEVELOPMENT OF A FAIRLY EXTENSIVE BAND OF MAINLY DIURNAL STORMS OVER THE SRN HI PLNS. A FEW STRONG TO POSSIBLY SEVERE WIND/HAIL EVENTS MAY OCCUR WITH THIS ACTIVITY THROUGH EARLY TONIGHT. ..CORFIDI/GRAMS.. 10/08/2006  From swody1 at goshenarc.org Sun Oct 8 16:22:59 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 08 Oct 2006 12:22:59 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 081625 SWODY1 SPC AC 081624 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT SUN OCT 08 2006 VALID 081630Z - 091200Z ...THERE IS A SLGT RISK OF SVR TSTMS ERN AZ AND WRN NM... ...SYNOPSIS... ANY SEVERE THUNDERSTORM THREAT THIS FORECAST PERIOD WILL BE ASSOCIATED WITH THE UPPER LOWS OVER SRN CA AND SERN GA. BOTH CIRCULATION CENTERS WILL TURN TOWARD THE E TODAY WITH THE GA SYSTEM MOVING OFFSHORE BY 00Z. ...EASTERN AZ/WRN NM... MOISTURE IS SPREADING BACK INTO ERN THIRD OF AZ AS WINDS HAVE BACKED TO THE E OF THE SRN CA UPPER LOW. AVAILABLE MOISTURE STILL IS NOT IMPRESSIVE BASED ON 12Z SOUNDING FROM TUS AND GPS PW READING OVER SRN AZ WITH GENERALLY .75 IN OR LESS. NWD TRANSPORT OF MOISTURE FROM NWRN MEX WILL CONTINUE THRU THE DAY ON THE INCREASING SLY FLOW AHEAD OF UPPER LOW. COMBINED WITH STRONG INSOLATION AND STEEPENING LAPSE RATES COUPLED WITH 35-40KT OF DEEP LAYER SHEAR...THUNDERSTORMS EXPECTED TO DEVELOP BY MID AFTERNOON E OF A LINE FROM MOGOLLON RIM SWD TO W OF NOG. WITH POTENTIAL FOR MLCAPES AOA 1000 J/KG AND 8C/KM MID LEVEL LAPSE RATES THERE IS AT LEAST A THREAT OF ISOLATED SEVERE STORMS BY LATE AFTERNOON CONTINUING THRU THE EVENING AS UPPER LOW APPROACHES FROM SERN CA. ...SC COAST... COMPACT UPPER LOW SERN GA WILL BE MOVING EWD OFFSHORE TONIGHT. THRU THIS AFTERNOON SELYS WILL CONTINUE A MOIST ONSHORE FLOW INTO SC COASTAL AREAS. AIR MASS OFFSHORE OVER GULF STREAM IS MOST UNSTABLE AND WITH FAVORABLE CYCLONIC SHEAR STRONG/ISOLATED SEVERE THUNDERSTORMS WILL CONTINUE TO MOVE TOWARD THE SC COAST UNTIL LATER THIS AFTERNOON. PRIMARY SEVERE THREAT WOULD BE ISOLATED WIND DAMAGE AND POSSIBLY A BRIEF TORNADO/WATER SPOUT WITH ANY SUPERCELL THAT MAY FORM OVER WATER AND MOVE ONSHORE. ..HALES/BOTHWELL.. 10/08/2006  From swody1 at goshenarc.org Tue Oct 10 05:54:39 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 01:54:39 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 100557 SWODY1 SPC AC 100556 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1256 AM CDT TUE OCT 10 2006 VALID 101200Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF CNTRL INTO ERN TX INTO WRN LA... ...SYNOPSIS... OPENING MID-LEVEL TROUGH ALONG THE AZ/NM BORDER IS FORECAST TO DE-AMPLIFY THROUGH THE PERIOD AS IT RAPIDLY TRANSLATES NEWD INTO THE MID MS VALLEY. AS THIS OCCURS...A STRONG SUBTROPICAL JET WILL BECOME ESTABLISHED FROM THE SWRN DESERTS TO THE LOWER MS VALLEY. IN THE LOW-LEVELS...SURFACE LOW ATTENDANT TO WEAKENING UPPER SYSTEM WILL DEVELOP NEWD FROM SWRN OR W-CNTRL TX INTO SRN MO BY LATE TONIGHT WITH TRAILING COLD FRONT PUSHING EWD THROUGH CNTRL/ERN TX. ...CNTRL/ERN TX INTO WRN LA... A COMPLEX FORECAST EXISTS OWING TO THE LIKELIHOOD OF AN ONGOING MCS OVER CNTRL TX AT THE ONSET OF THE FORECAST PERIOD...AND ITS EFFECTS ON AIR MASS DESTABILIZATION AND EVENTUAL FRONTAL MOVEMENT. 10/00Z SOUNDINGS FROM THE TX COAST INDICATE THAT A MOIST LOW-LEVEL AIR MASS HAS MOVED ONSHORE WITH LOWEST MEAN MIXING RATIOS OF AROUND 16 G/KG. CURRENT SURFACE OBSERVATIONS AND GOES GPS DATA SHOW THIS MOISTURE ADVECTING NWD INTO CNTRL TX ALONG ERN EDGE OF LLJ BECOMING ESTABLISHED OVER WRN TX. AS MENTIONED ABOVE...STORM CLUSTERS OR AN MCS WILL LIKELY BE ONGOING 10/12Z OVER THE EDWARDS PLATEAU REGION...DRIVEN LARGELY BY LOW-LEVEL WAA REGIME AHEAD OF WEAKENING MID-LEVEL TROUGH. CONSIDERABLE CLOUDS AND PRECIPITATION SHOULD LIMIT LAPSE RATES TO NEAR MOIST ADIABATIC WITH INCREASING BOUNDARY-LAYER MOISTURE LARGELY CONTRIBUTING TO AIR MASS DESTABILIZATION WITH MLCAPES OF 500-1000 J/KG EXPECTED. AS SUCH...SOME DIURNAL WEAKENING OF MCS MAY OCCUR DURING THE MORNING...PRIOR TO STORMS INTENSIFYING BY AFTERNOON OVER CNTRL TX SWD TOWARD THE MIDDLE TX COAST. VERTICAL SHEAR PROFILES WILL BECOME INCREASINGLY SUPPORTIVE OF SUPERCELLS/BOWING STRUCTURES CAPABLE OF MAINLY DAMAGING WINDS AND A FEW TORNADOES OWING TO PERSISTENT LOW-LEVEL WAA PATTERN COUPLED WITH INTENSIFYING SUBTROPICAL JET. ACTIVITY SHOULD MOVE/DEVELOP EWD INTO LA TONIGHT...WITH A CONTINUED THREAT OF ISOLATED DAMAGING WINDS AND PERHAPS A TORNADO OR TWO NEAR AND E OF THE SABINE RIVER VALLEY. FARTHER TO THE N OVER NERN TX INTO SERN OK AND SWRN AR...IT APPEARS THAT INSTABILITY WILL REMAIN QUITE LIMITED SHOULD MCS PERSIST ACROSS CNTRL/ERN TX AS IS BEING FORECAST. SHEAR PROFILES WILL BE SUPPORTIVE OF ORGANIZED...SEVERE STORMS...HOWEVER THE DEGREE OF INSTABILITY REMAINS IN QUESTION ATTM. ..MEAD/GRAMS.. 10/10/2006  From swody1 at goshenarc.org Tue Oct 10 12:48:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 08:48:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101251 SWODY1 SPC AC 101249 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 AM CDT TUE OCT 10 2006 VALID 101300Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF S CNTRL AND SE TX INTO WRN LA... ...SYNOPSIS... AMPLIFICATION OF NRN STREAM TROUGH DROPPING SSE FROM CNTRL CANADA WILL RESULT IN CONTINUED DEAMPLIFICATION OF SRN STREAM IMPULSE OVER NM. THE LATTER SYSTEM SHOULD ACCELERATE ENE ACROSS KS/OK TODAY BEFORE BECOMING ABSORBED INTO NRN TROUGH OVER THE MID MS VLY EARLY WEDNESDAY. AS THIS OCCURS...A STRONG LOW AMPLITUDE SUBTROPICAL JET WILL BECOME ESTABLISHED FROM THE SW U.S. TO THE LWR MS VLY. AT THE SURFACE...PATTERN HAS BEEN COMPLICATED BY ONGOING OVERNIGHT MCSS AND BY EXISTING FRONT THAT HAS BECOME NEARLY STATIONARY FROM THE TX BIG BEND ENE INTO SE OK. WEAK WAVE/INFLECTION AREA ALONG THE BOUNDARY SHOULD WEAKEN OVER S CNTRL TX TODAY AS A NEW WAVE EVENTUALLY FORMS DOWNSTREAM FROM EJECTING UPR VORT OVER THE OZARKS/MID MS VLY. TRAILING COLD FRONT FROM THE WAVE SHOULD ACCELERATE SE ACROSS CNTRL/ERN TX TONIGHT/EARLY WEDNESDAY. ...S CNTRL TX INTO SE TX/WRN LA... SUBSTANTIAL BOUNDARY LAYER MOISTENING HAS OCCURRED IN THE LAST 12-18 HRS ACROSS S CNTRL AND PARTS OF SE TX...WHERE SSELY LOW LEVEL FLOW HAS PREVAILED AND PWS ARE AOA 1.50 INCHES. SEVERAL SMALL MCSS THAT TRACKED ENE ACROSS SW AND S CNTRL TX OVERNIGHT HAVE REINFORCED SW PART OF SYNOPTIC FRONT NOW STALLED ROUGHLY ENE FROM THE TX BIG BEND. FARTHER E...SURFACE DATA AND AXIS OF PERSISTENT SHOWER DEVELOPMENT SUGGEST PRESENCE OF A DEVELOPING WARM FRONT EXTENDING N/S FROM W OF CLL TO NEAR VCT. HIGH CLOUDS WITH SUBTROPICAL JET AND LOW CLOUDS ASSOCIATED WITH UPSLOPE FLOW/WARM ADVECTION WILL SOMEWHAT LIMIT LOW LEVEL DESTABILIZATION IN WARM SECTOR TODAY. BUT GIVEN MOIST BOUNDARY LAYER ENVIRONMENT AND MODERATELY COOL MID LEVEL TEMPERATURES /AROUND MINUS 9 AT 500 MB/...EVEN MODEST HEATING SHOULD BOOST AFTN MLCAPE TO AROUND 1000 J/KG. VERTICAL SHEAR SHOULD REMAIN SUPPORTIVE OF SUPERCELLS/BOWING STRUCTURES CAPABLE OF ISOLATED TORNADOES AND LOCALLY DAMAGING WIND ...BOTH ALONG AFOREMENTIONED BOUNDARIES...AND LATER TODAY WITHIN WARM SECTOR. THE STORMS SHOULD MOVE/DEVELOP E INTO PARTS OF LA TONIGHT...WITH A CONTINUED THREAT FOR MAINLY ISOLATED DAMAGING WINDS AND PERHAPS A TORNADO NEAR AND E OF THE SABINE RVR. FARTHER NE ACROSS NE TX/SE OK AND SW AR...EXPECT THAT LOW LEVEL MOISTURE RETURN WILL BE MINIMAL. COUPLED WITH CLOUD COVER...IT APPEARS THAT INSTABILITY WILL REMAIN LIMITED. THUS...DESPITE PRESENCE OF AMPLE SHEAR FOR ORGANIZED SEVERE STORMS...AS WELL AS SOMEWHAT STRONGER FORCING FOR ASCENT THAN OVER POINTS SOUTH...SEVERE POTENTIAL SHOULD REMAIN LOW. ..CORFIDI.. 10/10/2006  From swody1 at goshenarc.org Tue Oct 10 16:13:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Tue, 10 Oct 2006 12:13:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 101615 SWODY1 SPC AC 101614 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1114 AM CDT TUE OCT 10 2006 VALID 101630Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS MUCH AND SOUTHERN AND SOUTHEAST TEXAS... ...SRN TX... UPPER LOW OVER SWRN U.S. MONDAY IS NOW AN OPEN WAVE AND ACCELERATING ENEWD ACROSS SRN HI PLAINS THIS AM. AN UNSEASONABLY STRONG POLAR TROUGH DIGGING INTO CENTRAL U.S. WILL RESULT IN SRN PLAINS SYSTEM TO STEADILY LOSE AMPLITUDE AS IT IS ABSORBED IN THE CONFLUENT FLOW OF THE MUCH STRONGER SYSTEM TO THE N. ONGOING LINEAR MCS NOW TRACKING ACROSS SCENTRAL TX IS BEING FED BY A VERY MOIST AND MODESTLY UNSTABLE SLY FLOW OFF THE WESTERN GULF OF MEXICO. THIS AM SHEAR PROFILES NOTED ON 88-D VADS AND LDB PROFILER SUPPORT SUPERCELL POTENTIAL. ALONG WITH LOW 70S F DEWPOINTS THAT RESULTS IN MLCAPE TO NEAR 1500 J/KG IN WARM SECTOR...WIND DAMAGE AND ISOLATED TORNADOES WILL CONTINUE TO BE A THREAT THRU MUCH OF THE AFTERNOON. SUPERCELLS WILL LIKELY BE EMBEDDED IN THE SQUALL LINE ASSOCIATED WITH THE MCS AS IT CONTINUES TO TRACK TOWARD SERN TX AND UPPER TX COASTAL AREA THIS EVENING. AN ADDITIONAL SEVERE THREAT WILL EXIST ALONG TRAILING CONVECTIVE BOUNDARY INTO SRN TX DURING AFTERNOON WHERE HEATING COULD WEAKEN CAP AND INCREASE INSTABILITY TO AOA 2000 J/KG. WEAKENING SHEAR THIS AREA SHOULD PRECLUDE MORE THAN AN ISOLATED SEVERE THREAT ON THE TRAILING PORTION OF THE OUTFLOW BOUNDARY AS LOW AND MID LEVEL FLOW VEERS AND WEAKENS LATER THIS AFTERNOON IN CONCERT WITH DE AMPLIFYING UPPER WAVE...SEVERE THREAT EXPECTED TO DIMINISH BY THIS EVENING ACROSS SERN TX/SWRN LA. ..HALES/CROSBIE.. 10/10/2006  From swody1 at goshenarc.org Sat Oct 14 05:38:03 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 01:38:03 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 140540 SWODY1 SPC AC 140538 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1238 AM CDT SAT OCT 14 2006 VALID 141200Z - 151200Z ...NO SVR TSTM AREAS FORECAST... ...SWRN U.S... LATE EVENING MODEL GUIDANCE IS SOMEWHAT CONFLICTING REGARDING THE SPEED/MOVEMENT OF UPPER LOW OFF THE SRN CA COAST INTO AZ LATE IN THE PERIOD. GFS IS SOMEWHAT FASTER AND WEAKER THAN THE NAM AS THIS FEATURE MOVES ACROSS THE SWRN DESERT REGIONS. DESPITE THE MODEL DIFFERENCES...LARGE SCALE ASCENT WILL CERTAINLY INCREASE WITHIN THE WARM CONVEYOR BELT AHEAD OF SFC WIND SHIFT DURING THE DAY ACROSS SERN AZ/SRN NM...ARCING NWWD INTO THE MOUNTAINS OF CNTRL AZ. CONVECTION SHOULD ONCE AGAIN DEVELOP WITHIN THIS STRONG BAROCLINIC ZONE...THOUGH BOUNDARY LAYER MOISTURE/INSTABILITY IS EXPECTED TO REMAIN SOMEWHAT MARGINAL. AT THIS TIME IT APPEARS STRENGTH OF UPDRAFTS WILL PROVE ROBUST WITHIN STRONGLY SHEARED ENVIRONMENT...BUT THERMODYNAMICALLY LACKING FOR ORGANIZED SEVERE THUNDERSTORMS. ANY SEVERE THREAT WILL BE LIMITED TO MAINLY MARGINALLY SEVERE HAIL...AND THIS SHOULD REMAIN SOMEWHAT ISOLATED AND STRONGLY DIURNAL. ...TX COAST... EARLY MORNING SATELLITE IMAGERY SUGGESTS A DEEP TROPICAL CONNECTION FROM LOW LATITUDES EXTENDS FROM CNTRL MEXICO...NEWD INTO THE WRN GULF OF MEXICO. MULTIPLE CLUSTERS OF THUNDERSTORMS EXISTS WITHIN THIS ZONE SOUTH OF THE TX BORDER...EXTENDING WELL SOUTH OF SFC WIND SHIFT. MODELS INSIST A WEAK DISTURBANCE WILL LIFT NEWD WITHIN THIS TROPICAL FEED AND INDUCE WEAK SFC DEVELOPMENT...EITHER IN THE FORM OF A WEAK SFC WAVE...OR PERHAPS A WEAK CLOSED SFC LOW ALONG THE RETREATING BOUNDARY ACROSS THE WRN GULF OF MEXICO NEAR THE LOWER/MIDDLE TX COAST LATE IN THE PERIOD. UNDOUBTEDLY...THIS BAROCLINIC ZONE WILL BE OF CONCERN AS IT FOCUSES DEEP CONVECTION WITHIN INCREASINGLY UNSTABLE/SHEARED LOW LEVEL AIRMASS. AT THIS TIME IT APPEARS GREATEST CONCENTRATION OF INTENSE THUNDERSTORM UPDRAFTS WILL OCCUR JUST OFFSHORE...AT LEAST THROUGH MUCH OF THE PERIOD. WITH TIME THIS BOUNDARY SHOULD MOVE INLAND...BUT IT MAY NOT DO SO UNTIL LATE DAY1 OR PERHAPS DAY2. WILL MAINTAIN LOW PROBABILITIES FOR ISOLATED SEVERE WITH NEAR-SFC BASED SUPERCELL ACTIVITY ALONG THE TX COAST...ESPECIALLY LATE IN THE PERIOD. ..DARROW/GUYER.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 12:35:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 08:35:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141237 SWODY1 SPC AC 141236 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0736 AM CDT SAT OCT 14 2006 VALID 141300Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS PART OF SERN CA/SRN NV INTO NWRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SRN AND MIDDLE TX COAST LATER TONIGHT... ...SOUTHWEST... EARLY MORNING SURFACE ANALYSES INDICATE LOW CENTER...ASSOCIATED WITH STRONG UPPER LOW NOW MOVING ACROSS SRN CA...IS DEEPENING OVER THE LOWER CO RIVER VALLEY BETWEEN EED AND IGM. ENHANCED LOW LEVEL CONVERGENCE IS INCREASING DEEP ASCENT NEAR THIS FEATURE WHERE SUPERCELLS AND SMALL LINES/BOW ECHOES HAVE PERSISTED OVERNIGHT OVER FAR ERN SAN BERNADINE CO/CA INTO CLARK CO/NV AND SRN MOHAVE CO/AZ. NARROW AXIS OF 55-60 F SURFACE DEW POINTS AND MODEST WARM SECTOR WITH TEMPERATURES AROUND 70F IS SUSTAINING 500 J/KG MLCAPE WITH LITTLE OR NO CINH FROM THE PHX AREA NWWD INTO SERN CA/SRN NV AS OF 12Z. AS 50+ KT SSWLY MID LEVEL JET OVERSPREADS THE REGION...LOW AND DEEP LAYER SHEAR WILL REMAIN ENHANCED TODAY AND LIKELY CONTINUE TO SUPPORT ORGANIZED STORMS INCLUDING SUPERCELLS. THOUGH INSTABILITY WILL REMAIN MEAGER... STRENGTH OF DEEP ASCENT AND SHEAR SHOULD SUPPORT A THREAT OF LARGE HAIL AND DAMAGING WINDS WITH MORE ORGANIZED STORMS AS THEY LIFT NNEWD TODAY. ACTIVITY WILL LIKELY LOSE INTENSITY AS IT SPREADS NWD INTO GREATER STABILITY INTO NERN AZ/CENTRAL NM. ...SRN/CENTRAL TX COASTAL PLAIN... SUBTLE TROPICAL IMPULSE CONTINUES TO SHIFT SLOWLY ACROSS MEXICO THIS MORNING...WHICH IS FORECAST TO AMPLIFY A SURFACE WAVE ALONG QUASI-STATIONARY FRONT NOW EXTENDING FROM DEEP SOUTH TX INTO THE NWRN GULF OF MEXICO DURING LATTER HALF OF THE PERIOD. CLUSTERS OF THUNDERSTORMS WILL LIKELY INCREASE LATER TONIGHT NEAR THIS SURFACE FRONT...AND AHEAD OF WEAK SRN STREAM WAVE...ESPECIALLY AS SSELY H85 WINDS STRENGTHEN AFTER 03Z. GIVEN INFLUX OF MID/UPPER 70F SURFACE DEW POINTS AND FORECAST 0-1 KM SRH IN EXCESS OF 100 M2/S2...LOW LEVEL ROTATION WILL STRENGTHEN WITH OVERNIGHT STORMS ALONG THE LOWER-MIDDLE TX COAST. APPEARS THE POTENTIAL FOR ISOLATED TORNADOES/DAMAGING WINDS WILL LIKEWISE INCREASE AFTER DARK. ..EVANS/GUYER.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 16:34:04 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 12:34:04 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141636 SWODY1 SPC AC 141634 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1134 AM CDT SAT OCT 14 2006 VALID 141630Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS CENTRAL AND NRN AZ... ...THERE IS A SLGT RISK OF SVR TSTMS LATE TONIGHT ACROSS THE LOWER AND MIDDLE TX COAST... ...AZ TODAY... A COLD CORE LOW OVER SE CA WILL MOVE SLOWLY EWD TO WRN AZ THIS AFTERNOON AND CENTRAL AZ OVERNIGHT. A BELT OF 45-60 KT SLY/SSWLY MID LEVEL FLOW E OF THE LOW WILL SPREAD EWD OVER AZ TODAY...COINCIDENT WITH A PLUME OF LOW-MID LEVEL MOISTURE AND ASCENT. SCATTERED THUNDERSTORMS WILL PERSIST THROUGH THE DAY WITHIN THIS BAND MAINLY ALONG AND N OF THE MOGOLLON RIM...WHERE VERTICAL SHEAR PROFILES WILL BE SUFFICIENT FOR A FEW SUPERCELLS. THE MORE INTENSE STORMS WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL...ALONG WITH THE POSSIBILITY OF AN ISOLATED TORNADO. PLEASE REFER TO MCD 2110 /VALID THROUGH 18Z/ FOR ADDITIONAL INFORMATION. ...W TX/SRN NM LATER TODAY INTO EARLY TONIGHT... A BROAD FETCH OF L0W-MID LEVEL MOISTURE IS SPREADING NEWD FROM THE CENTRAL/SRN GULF OF CA AND NW MEXICO INTO SRN NM AND FAR W TX...IN ADVANCE OF THE MID LEVEL LOW OVER THE LOWER CO RIVER VALLEY. FARTHER E...BOUNDARY LAYER DEWPOINTS IN THE LOWER 60S ARE SPREADING NWWD UP THE PECOS VALLEY INTO SW TX/SE NM. REGIONAL 12Z SOUNDINGS SHOWED RATHER MODEST MID LEVEL LAPSE RATES GENERALLY AOB 6 C/KM...WHILE SATELLITE IMAGERY SUGGEST THAT WIDESPREAD CLOUDS WILL PERSIST THROUGH MUCH OF THE DAY AND LIMIT SURFACE HEATING /ESPECIALLY THE PECOS VALLEY/. STILL...BOUNDARY LAYER DEWPOINTS IN THE MID-UPPER 50S AND SOME CLOUD BREAKS BY LATE AFTERNOON MAY SUPPORT THE DEVELOPMENT OF ISOLATED STRONGER STORMS ACROSS FAR W TX AND SW NM...AND SCATTERED THUNDERSTORMS SHOULD FORM BY THIS EVENING ACROSS SW TX/SE NM. VERTICAL SHEAR WILL BE FAVORABLE FOR SUPERCELLS OVER THIS ENTIRE AREA...AND THE MORE INTENSE STORMS COULD PRODUCE ISOLATED/MARGINALLY SEVERE HAIL AND WIND DAMAGE THROUGH EARLY TONIGHT. ...S TX LATE TONIGHT... A LARGE CLUSTER OF THUNDERSTORMS PERSISTS OVER THE W CENTRAL AND SW GULF OF MEXICO IN ASSOCIATION WITH A WEAK MID LEVEL WAVE LIFTING NNEWD NEAR TAMPICO. THIS WAVE/CONVECTION WILL INTERACT WITH THE BAROCLINIC ZONE ACROSS THE LOWER TX COAST AND ADJACENT NW GULF...SUPPORTING WEAK CYCLOGENESIS/STRENGTHENING GRADIENTS AND AN ASSOCIATED INCREASE IN LOW-LEVEL SHEAR. FORECAST SOUNDINGS SHOW SOME POTENTIAL FOR ROTATING STORMS WITH STRONG LOW-LEVEL SHEAR IN A VERY MOIST ENVIRONMENT WITH WEAK INSTABILITY...WHICH MAY SUPPORT AN ISOLATED TORNADO OR TWO BEFORE 12Z. ..THOMPSON/TAYLOR.. 10/14/2006  From swody1 at goshenarc.org Sat Oct 14 19:44:43 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 15:44:43 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 141945 SWODY1 SPC AC 141943 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT SAT OCT 14 2006 VALID 142000Z - 151200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF CNTRL AZ...NRN AZ AND FAR SRN NV... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER TX COAST... ...CNTRL AND NRN AZ/FAR SRN NV... A WELL-DEVELOPED UPPER-LOW OVER SRN CA WILL DRIFT EWD THIS AFTERNOON INTO AZ WITH A DUAL-CENTERED SFC LOW REMAINING PRESENT ACROSS CNTRL AZ. THUNDERSTORMS ARE DEVELOPING JUST AHEAD OF THE TRACK OF THE UPPER-LOW IN THE LEFT EXIT REGION OF A 70 KT MID-LEVEL JET. THE CONVECTION SHOULD GRADUALLY EXPAND IN COVERAGE EWD WITH INDIVIDUAL CELL ELEMENTS MOVING NWD ACROSS CNTRL AND NRN AZ THROUGH THIS EVENING...REF 2111 VALID THROUGH 21Z. ALTHOUGH INSTABILITY STILL REMAINS WEAK THIS AFTERNOON...FURTHER DESTABILIZATION REMAINS POSSIBLE OVER CNTRL AND NRN AZ AS A DRY SLOT EVIDENT ON WATER VAPOR IMAGERY OVER SRN CA AND WRN AZ ADVANCES NNEWD. MID-LEVEL LAPSE RATES ARE ALREADY STEEP AND CONTINUED SFC HEATING SHOULD HELP LOW-LEVEL LAPSE RATES TO STEEPEN FURTHER LATE THIS AFTERNOON. THIS COMBINED WITH 500 MB TEMPS OF -18 TO -20 C AND THE STRONG VERTICAL SHEAR ASSOCIATED WITH THE MID-LEVEL JET MAY RESULT IN SEVERE STORMS CAPABLE FOR HAIL AND ISOLATED WIND DAMAGE MAINLY LATE THIS AFTERNOON INTO EARLY THIS EVENING. ...LOWER TX COAST... SOUTHWEST FLOW ALOFT WILL REMAIN IN PLACE ACROSS SOUTH TX AS A WELL-DEVELOPED UPPER-LOW ADVANCES EWD ACROSS THE SWRN STATES TONIGHT. IN RESPONSE...A STRONG LOW-LEVEL JET IS FORECAST TO DEVELOP ACROSS THE SRN PLAINS AND THIS WILL HELP TO LIFT A WARM FRONT NNEWD ALONG THE LOWER TX COAST. STRONG LIFT ASSOCIATED WITH THE LOW-LEVEL JET SHOULD RESULT IN MCS DEVELOPMENT OVERNIGHT WITH STORM COVERAGE INCREASING FROM SOUTH TO NORTH ACROSS SOUTH TX AFTER MIDNIGHT. THE LOW-LEVEL JET WILL ALSO INCREASE SHEAR PROFILES WITH FORECAST SOUNDINGS LATE TONIGHT SHOWING 0-1 KM SHEAR VALUES REACHING ABOUT 25 KT ACROSS SOUTH TX. THIS COMBINED WITH SFC DEWPOINTS IN THE MID 70S F MAY RESULT IN AN ISOLATED TORNADO THREAT WITH ROTATING STORMS THAT MOVE NWD ACROSS THE REGION LATE TONIGHT. ..BROYLES.. 10/14/2006  From swody1 at goshenarc.org Sun Oct 15 00:45:32 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 14 Oct 2006 20:45:32 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150047 SWODY1 SPC AC 150046 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0746 PM CDT SAT OCT 14 2006 VALID 150100Z - 151200Z ...NO SVR TSTM AREAS FORECAST... ...W TX... SCATTERED STRONG STORMS CONTINUE DEVELOPING WITHIN THE BROAD FETCH OF SUBTROPICAL MOISTURE AND LARGE SCALE ASCENT ACROSS W AND SWRN TX INTO SERN NM DOWNSTREAM FROM UPPER LOW OVER AZ. MODEST SELY LOW LEVEL FLOW BENEATH MODERATE 40-45 KT WLY MID LEVEL FLOW IS RESULTING IN SUFFICIENT DEEP LAYER SHEAR FOR SUPERCELLS. STRONGEST STORMS REMAIN OVER SWRN TX EARLY THIS EVENING WHERE THE BOUNDARY LAYER EXPERIENCED MORE HEATING EARLIER TODAY...RESULTING IN MLCAPE FROM 500 TO 800 J/KG. STORMS DEVELOPING FARTHER N ACROSS W TX ARE PROBABLY SLIGHTLY ELEVATED ABOVE A BOUNDARY LAYER THAT HAS BEEN RENDERED LESS UNSTABLE BY EXTENSIVE STRATUS. THE 00Z RAOB FROM AMARILLO CONFIRMS THE STABLE LAYER NEAR THE SURFACE IS RATHER SHALLOW IN THIS REGION. A SLY LOW LEVEL JET WILL STRENGTHEN OVER W TX THIS EVENING WITHIN ZONE OF HEIGHT FALLS DOWNSTREAM FROM UPPER LOW. HOWEVER...INSTABILITY WILL BECOME INCREASINGLY MARGINAL OVER SWRN TX AS THE BOUNDARY LAYER COOLS. PRIMARY THREAT APPEARS TO BE ISOLATED MARGINALLY SEVERE HAIL AND STRONG WIND GUSTS WITH ROTATING STORMS. OVERALL THREAT IS SOMEWHAT LIMITED BY WEAK INSTABILITY. ...SRN TX... SCATTERED CONVECTION WILL CONTINUE DEVELOPING PRIMARILY WITHIN ZONE OF LIFT ACCOMPANYING A NEWD EJECTING IMPULSE AND IN VICINITY OF WARM FRONT AS IT LIFTS SLOWLY NWD THROUGH SRN TX AND THE WRN GULF. AN ELY LOW LEVEL JET IS FORECAST TO STRENGTHEN IN THIS REGION LATER TONIGHT AND SHOULD AUGMENT LOW LEVEL SHEAR PROFILES. HOWEVER...FLOW IN THE 3-6 KM LAYER WILL REMAIN WEAK DUE TO PROXIMITY OF A BROAD UPPER RIDGE. THOUGH RICH LOW LEVEL MOISTURE IS IN PLACE...PRIMARY LIMITING FACTOR FOR A MORE ROBUST SEVERE THREAT WILL BE WEAK LAPSE RATES AND INSTABILITY ASSOCIATED WITH DEEP MOIST ADIABATIC PROFILES. AN OUTSIDE CHANCE FOR AN ISOLATED TORNADO MAY EXIST LATER TONIGHT AS THE LOW LEVEL WIND PROFILES INCREASE. HOWEVER...OVERALL THREAT APPEARS LIMITED. ..DIAL.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 05:37:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 01:37:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 150539 SWODY1 SPC AC 150537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1237 AM CDT SUN OCT 15 2006 VALID 151200Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE TX COASTAL AREA INTO SRN LA... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SERN NM INTO WRN TX... ...SYNOPSIS... UPPER LOW CURRENTLY OVER AZ SHOULD ADVANCE EWD INTO ERN NM BY SUNDAY NIGHT AS AN UPSTREAM IMPULSE AMPLIFIES INTO THE PACIFIC NW. THE GFS IS A LITTLE FASTER THAN THE NAM IN EJECTING THIS SRN STREAM WAVE. POTENTIAL WILL ALSO EXIST FOR WEAKER IMPULSES TO EJECT NEWD AHEAD OF MAIN UPPER TROUGH. COASTAL FRONT OVER THE WRN GULF WILL LIFT NWD THROUGH SERN TX INTO SRN LA SUNDAY AND SUNDAY NIGHT AS A STRONG SLY LOW LEVEL JET DEVELOPS IN ADVANCE OF THE UPPER TROUGH. ...SERN TX THROUGH SRN LA... LOW LEVEL DEWPOINTS IN THE LOWER 70S OVER S TX WILL ADVECT NWD INTO PARTS OF SERN TX AND SRN LA SUNDAY AND SUNDAY NIGHT S OF RETREATING WARM FRONT. HOWEVER...INSTABILITY SHOULD REMAIN LIMITED DUE TO MOIST ADIABATIC PROFILES AND WIDESPREAD CLOUDS AND RAIN. SBCAPE FROM 500 TO 1000 J/KG WILL BE POSSIBLE AS LOW 70S DEWPOINTS ADVECT INLAND S OF RETREATING FRONT. SLY LOW LEVEL JET IS FORECAST TO STRENGTHEN TO IN EXCESS OF 50 KT OVER ERN TX SUNDAY AND SHIFT INTO LA SUNDAY NIGHT WITHIN ZONE OF HEIGHT FALLS DOWNSTREAM FROM UPPER TROUGH. DIFFERENCES EXIST BETWEEN THE NAM AND GFS IN HANDLING THE LOW LEVEL MASS FIELDS...WITH THE GFS BEING WEAKER AND DISPLACED FARTHER EAST WITH ITS LOW LEVEL JET. HOWEVER...OVERALL PATTERN WOULD SUGGEST 0-1 KM HODOGRAPHS MAY BECOME SUPPORTIVE OF LOW LEVEL MESOCYCLONES FROM SERN TX COAST INTO SRN LA WITHIN A MOIST LOW LEVEL THERMODYNAMIC ENVIRONMENT. CONVECTION WILL CONTINUE TO SPREAD NWD INTO SERN TX AND SRN LA SUNDAY AND SUNDAY NIGHT. POTENTIAL WILL EXIST FOR ISOLATED EMBEDDED SUPERCELLS WITHIN THE LARGER AREA OF CONVECTION AS LOW LEVEL WIND FIELDS STRENGTHEN...ESPECIALLY IF POCKETS OF HEATING CAN DEVELOP. MAIN THREAT WILL BE ISOLATED TORNADOES AND POSSIBLY DAMAGING WIND GUSTS. MARGINAL THERMODYNAMIC PROFILES WILL REMAIN THE PRIMARY LIMITING FACTOR. ...NM INTO FAR WRN TX... STEEPER MID LEVEL LAPSE RATES SHOULD SPREAD EWD THROUGH NM INTO FAR W TX ABOVE LOW LEVEL DEWPOINTS IN THE UPPER 50S TO LOWER 60S AS THE UPPER TROUGH ADVANCES EWD. SATELLITE IMAGERY SUGGESTS AN UPPER LEVEL DRY SLOT COULD SHIFT INTO PARTS OF ERN NM AND WRN TX AHEAD OF MAIN VORT MAX DURING THE AFTERNOON. HOWEVER...WITH LOW LEVEL FLOW EXPECTED TO REMAIN WEAK IN THIS REGION...LOW CLOUDS COULD BE SLOW TO MIX OUT. WHERE POCKETS OF HEATING CAN DEVELOP MLCAPE AROUND 1000 J/KG WILL BE POSSIBLE. IF SUFFICIENT DESTABILIZATION OCCURS...STORMS MAY INTENSIFY WITHIN ZONE OF CVA FROM NM INTO WRN TX DURING THE AFTERNOON AND EARLY EVENING. VERTICAL WIND PROFILES WILL WITH DEEP LAYER SHEAR FROM 50 TO 60 KT WILL SUPPORT SUPERCELL STORMS WITH LARGE HAIL THE PRIMARY THREAT. ..DIAL.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 12:34:05 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 08:34:05 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151235 SWODY1 SPC AC 151233 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0733 AM CDT SUN OCT 15 2006 VALID 151300Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER SERN NM AND SWRN TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE MIDDLE/UPPER TX AND SWRN LA COAST... ...SERN NM/SWRN TX... MID LEVEL LAPSE RATES WILL STEEPEN AS STRONG ASCENT SPREADS FROM WEST TO EAST ACROSS THIS REGION TODAY AHEAD OF APPROACHING UPPER LOW. STORMS EARLY THIS MORNING HAVE ALREADY ORGANIZED INTO SMALL SUPERCELLS...INDICATING 500-1000 J/KG MUCAPE IS MORE THAN ADEQUATE FOR INTENSE/ORGANIZED STORMS GIVEN VERY STRONG DEEP LAYER SHEAR. FORECAST SOUNDINGS SUGGEST STORMS THIS MORNING REMAIN SLIGHTLY ELEVATED ABOVE A STABLE SURFACE LAYER...THOUGH LONGER-LIVED STORMS WILL BE CAPABLE OF MARGINALLY SEVERE HAIL AND ISOLATED STRONG/DAMAGING WINDS. EXPECT LACK OF MID/HIGH LEVEL CLOUDS WILL ALLOW SOME MIXING TO OCCUR OVER HIGHER TERRAIN OF FAR SWRN TX/SRN NM/NRN CHIHUAHUA TO THE SOUTH OF SURFACE FRONT NOW EXTENDING FROM W-CENTRAL TX SWWD INTO SWRN NM. WHERE POCKETS OF HEATING CAN OCCUR....MLCAPE FROM 500-1000 J/KG COULD DEVELOP ALONG NWRN EXTENT OF LOWER 60F SURFACE DEW POINT AXIS EXTENDING INTO SWRN TX/FAR SERN NM THIS AFTERNOON. EFFECTIVE SHEAR NEAR 50 KT WILL BE SUFFICIENT FOR A FEW SURFACE-BASED SUPERCELLS/ORGANIZED CLUSTERS THIS AFTERNOON AND EVENING. IF SUFFICIENT MLCAPE CAN DEVELOP...LARGE HAIL WILL BE PRIMARY SEVERE THREAT ALONG WITH ISOLATED DAMAGING WINDS. ...MIDDLE/UPPER TX COAST INTO SWRN LA... RICH TROPICAL MOISTURE CONTINUES TO LIFT NWD ACROSS THE WRN GULF OF MEXICO THIS MORNING WITH PW/S IN EXCESS OF 2 INCHES AND SURFACE DEW POINTS IN THE MID/UPPER 70S LIKELY SPREADING INTO THE UPPER TX/SWRN LA COAST TODAY. THIS WILL OCCUR UNDER INCREASING SLY H85 FLOW AHEAD OF APPROACHING MID/UPPER LOW NOW MOVING INTO THE SRN ROCKIES. MODELS ARE CONSISTENT IN DEVELOPING 50+ KT LLJ INTO SERN TX BY 00Z...WHICH STRENGTHENS TO NEAR 70 KT OVERNIGHT ACCORDING TO THE NAM/WRF. THUNDERSTORMS WILL STEADILY INCREASE INTO THE MIDDLE/UPPER TX COAST AND SWRN LA THROUGH THE DAY AND CONTINUE OVERNIGHT ALONG AND NORTH OF MARITIME WARM FRONT NOW DEVELOPING ALONG AND JUST OFF THE UPPER TX COAST. THOUGH DEEP MOIST PROFILES WILL LIMIT AVAILABLE INSTABILITY....RICH LOW LEVEL MOISTURE AND TEMPERATURES APPROACHING THE LOWER 80S SHOULD BE COMMON BEHIND THIS WARM FRONT. THIS IS EXPECTED TO RESULT IN MARGINAL SURFACE-BASED INSTABILITY WITHIN EXTREME LOW LEVEL SHEAR AND HIGH VALUES OF BOUNDARY LAYER RELATIVE HUMIDITY. THIS WILL SUPPORT AN INCREASINGLY FAVORABLE ENVIRONMENT FOR LOW LEVEL ROTATION WHERE POCKETS OF SURFACE-BASED CAPE CAN MAXIMIZE...ESPECIALLY LATER TODAY AND TONIGHT UNDER STRENGTHENING LLJ AXIS. FAST MOVING SMALL LINES AND SUPERCELLS ARE EXPECTED TO DEVELOP DURING THIS PERIOD WITH ATTENDANT THREATS OF DAMAGING WINDS AND ISOLATED TORNADOES. ..EVANS/GUYER.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 16:29:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 12:29:53 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151632 SWODY1 SPC AC 151630 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1130 AM CDT SUN OCT 15 2006 VALID 151630Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF NM AND W TX... ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SE TX AND SW LA... ...SYNOPSIS... AZ UPR LOW APPEARS TO HAVE REACHED ABOUT MAXIMUM INTENSITY AND SHOULD BEGIN TO DEAMPLIFY AS IT CONTINUES SLOWLY E OR ESE INTO SW NM LATER TODAY. DOWNSTREAM FROM THE LOW...EXPECT MID LEVEL SWLY FLOW TO SLOWLY STRENGTHEN FROM W TO E ACROSS TX THROUGH 12Z MONDAY. AT THE SURFACE...DIFFUSE WARM FRONT SHOULD LIFT FARTHER N ACROSS SE TX/CSTL LA TODAY/TONIGHT...WHILE WEAK INVERTED TROUGH HOLDS MORE OR LESS STATIONARY FROM THE TX S PLNS ENE INTO N CNTRL TX. ...SRN AND ERN NM/W TX... SCTD STRONG TO SEVERE STORMS/SUPERCELLS EXPECTED TO PERSIST THROUGH TONIGHT/EARLY MONDAY INVOF WSW/ENE ORIENTED SURFACE TROUGH EXTENDING FROM SRN NM INTO NW/N CNTRL TX. MODERATE BUT VERY MOIST /850 MB DEWPOINTS AOA 15 C/ SLY LOW LEVEL FLOW WILL CONTINUE BENEATH 40-50 KT SW FLOW DOWNSTREAM FROM AZ LOW. WHILE NO DISTINGUISHABLE SHORTWAVE IMPULSES ARE APPARENT IN SATELLITE IMAGERY...GENERAL LARGE SCALE ASCENT SHOULD MAINTAIN FAVORABLE ENVIRONMENT FOR STORM DEVELOPMENT AS LOW CONTINUES EWD. ACTIVITY MAY BE ENHANCED LATER TODAY ACROSS SRN NM AND FAR W TX BY HEATING OVER HIGHER TERRAIN. LARGE HAIL SHOULD BE THE MAIN SEVERE THREAT...ALTHOUGH LOCALLY DAMAGING WIND AND AN ISOLATED TORNADO COULD OCCUR WITH STRONGER/MORE SUSTAINED UPDRAFTS. ...SE TX/SW LA... VERY RICH TROPICAL MOISTURE /850 MB DEWPOINTS ABOVE 16 C/ WILL CONTINUE TO STREAM NWD INTO SE TX AND EVENTUALLY SRN LA THIS PERIOD AS MARITIME WARM FRONT LIFTS FARTHER N. SHORTWAVE FORCING FOR ASCENT WILL REMAIN WEAK...AND MID LEVEL LAPSE RATES WILL REMAIN NEAR MOIST ADIABATIC. BUT GENERAL AREA OF UPR DIFFLUENCE DOWNSTREAM FROM DISTURBANCES OVER MEXICO AND THE WRN GULF...ALONG WITH LOW LEVEL WARM ADVECTION...SHOULD MAINTAIN GOOD SETUP FOR SHOWERS/STORMS NOW OVER THE NWRN GULF TO MOVE/DEVELOP N ACROSS THE SE TX CSTL PLN. GIVEN RICH MOIST ENVIRONMENT...EXPECTED STRENGTHENING OF LLJ DOWNSTREAM FROM EJECTING AZ LOW MAY FOSTER LOW LEVEL UPDRAFT ROTATION AND THE POTENTIAL FOR TORNADOES. THIS ACTIVITY MAY BEGIN AS SURFACE HEATING ENHANCES LOW LEVEL DESTABILIZATION LATER TODAY...BUT THE GREATEST THREAT MAY EVOLVE TONIGHT AND EARLY MONDAY AS SLY LLJ INCREASES TO AOA 50 KTS. ..CORFIDI/TAYLOR.. 10/15/2006  From swody1 at goshenarc.org Sun Oct 15 19:48:27 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 15:48:27 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 151950 SWODY1 SPC AC 151949 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0249 PM CDT SUN OCT 15 2006 VALID 152000Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF SE NM AND WEST TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF EAST TX AND LA... ...WEST TX/SE NM... AN UPPER-LOW OVER AZ WILL CONTINUE TO MOVE EWD TOWARD THE REGION THIS AFTERNOON. SCATTERED THUNDERSTORMS ARE ONGOING AHEAD OF A DRY SLOT EVIDENT ON WATER VAPOR OVER SRN NM. AS THIS FEATURE MOVES ENEWD...LARGE-SCALE ASCENT AHEAD OF THE UPPER-LOW WILL SUPPORT THE DEVELOPMENT OF NUMEROUS THUNDERSTORMS THIS AFTERNOON INTO THE OVERNIGHT PERIOD. LATEST SFC ANALYSIS SHOWS LOWER TO MID 60S F DEWPOINTS EXTENDING NEWD FROM FAR WEST TX ALONG THE ERN EDGE OF THE CAPROCK INTO THE SERN TX PANHANDLE. THUNDERSTORMS ARE DEVELOPING ON THE COOL SIDE OF THE MOISTURE GRADIENT WHERE FORCING WITH THE UPPER-TROUGH IS STRONGEST. THIS COMBINED WITH STRONG VERTICAL SHEAR WILL BE TWO FACTORS SUPPORTIVE OF SEVERE WEATHER THIS AFTERNOON. HAIL WILL BE POSSIBLE ESPECIALLY AS LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-TROUGH AND COOLER MID-LEVEL TEMPS MOVE EWD INTO WEST TX LATE THIS AFTERNOON. HAIL WILL BE MOST LIKELY WITH THE STRONGER THUNDERSTORMS THAT DEVELOP ALONG THE NWRN EDGE OF THE MOISTURE GRADIENT WHERE CONVECTIVE COVERAGE HAS BEEN MINIMAL AND INSTABILITY IS LOCALLY ENHANCED. ...EAST TX/LA... LATEST WATER VAPOR ANALYSIS SHOWS A VERY LARGE MCS JUST OFF THE TX COAST WITH MID-LEVEL MOISTURE INCREASING ALONG THE TX COAST FROM SOUTHWEST TO NORTHEAST. THIS MOISTURE COMBINED WITH THE EXPANDING LOW-LEVEL JET AND DESTABILIZATION SHOULD MAKE MCS DEVELOPMENT MORE LIKELY ACROSS THE TX COASTAL PLAINS LATE THIS AFTERNOON INTO THE EVENING. MODEL FORECASTS ARE CONSISTENT WITH AN MCS DEVELOPING AND MOVING NWD ACROSS EAST TX INTO WRN LA DURING THE OVERNIGHT PERIOD. THE LATEST WSR-88D VWPS FROM THE HOUSTON AREA SHOW IMPRESSIVE SHEAR PROFILES WITH STRONG VEERING WITH HEIGHT AND 0-1 KM SHEAR VALUES AROUND 30 KT. THIS SHOULD BE FAVORABLE FOR ROTATING STORMS MOVING NWD ACROSS THE REGION THIS AFTERNOON. AS THE LOW-LEVEL JET INTENSIFIES TO 60-70 KT ACROSS EAST TX TONIGHT...THE TORNADO THREAT SHOULD INCREASE AND GRADUALLY EXPAND NWD. ALTHOUGH TORNADOES SHOULD BE THE MOST LIKELY TYPE OF SEVERE WEATHER...THE HIGH SFC DEWPOINTS AND STRONG LOW-LEVEL FLOW MAY BE SUPPORTIVE OF A FEW DAMAGING WIND GUSTS DURING THE OVERNIGHT PERIOD AS WELL. ..BROYLES.. 10/15/2006  From swody1 at goshenarc.org Mon Oct 16 00:53:52 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 15 Oct 2006 20:53:52 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160055 SWODY1 SPC AC 160053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT SUN OCT 15 2006 VALID 160100Z - 161200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF SOUTHEAST NM AND WEST TX... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF SOUTHEAST TX AND WESTERN LA... ...SOUTHWEST NM/WEST INTO NORTHWEST TX... LARGE UPPER TROUGH OVER AZ/NM IS FORECAST TO SHIFT EASTWARD INTO TX TONIGHT...WITH STRONG FORCING FOR ASCENT OVERSPREADING MUCH OF WEST/CENTRAL TX. THIS WILL MAINTAIN SCATTERED THUNDERSTORM ACTIVITY ACROSS WEST TX OVERNIGHT. POCKETS OF DAYTIME HEATING ALLOWED AIR MASS SOUTH OF MAF TO BECOME MODERATELY UNSTABLE WITH TEMPERATURES IN THE MID 70S AND MLCAPE UP TO 500 J/KG. VERTICAL SHEAR PROFILES IN THIS AREA ARE FAVORABLE FOR SUPERCELLS AND ISOLATED TORNADOES. ALTHOUGH STORMS WILL LIKELY AFFECT REGION THROUGH THE EVENING... STORMS MAY BECOME PROGRESSIVELY MORE ELEVATED AS BOUNDARY LAYER COOLS. LARGE HAIL SHOULD BECOME THE MAIN THREAT AFTER 03Z. STORMS MAY ALSO EXPAND IN COVERAGE TONIGHT AND SPREAD NORTHEASTWARD TOWARD NORTHWEST TX/SOUTHWEST OK...WITH A CONTINUED THREAT OF MARGINALLY SEVERE HAIL. ...SOUTHEAST TX AND WESTERN LA... RADAR/SATELLITE IMAGERY CONTINUE TO SHOW VERY LARGE MCS OVER THE WESTERN GULF OF MEXICO SOUTH OF HOU. THIS CONVECTION AND ASSOCIATED WARM FRONT IS EXPECTED TO LIFT SLOWLY NORTHWARD OVERNIGHT...MOVING ONSHORE ALONG THE UPPER TX AND SOUTHWEST LA COAST. MODELS ARE IN GENERAL AGREEMENT THAT SOUTHERLY LOW LEVEL JET WILL STRENGTHEN TO OVER 50 KNOTS AFTER 06Z IN THIS REGION. VERY MOIST LOW LEVEL AIR MASS /DEWPOINTS IN THE MID 70S/...COUPLED WITH INCREASING LOW LEVEL VERTICAL SHEAR PROFILES SUGGEST A THREAT OF ISOLATED SUPERCELLS EMBEDDED WITHIN LARGER RAIN SHIELD. THIS PSEUDO-TROPICAL SITUATION COULD RESULT IN ISOLATED TORNADOES AND DAMAGING WINDS OVERNIGHT IN STRONGER CELLS...PRIMARILY NEAR THE COAST. ..HART.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 05:27:36 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 01:27:36 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 160529 SWODY1 SPC AC 160528 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1228 AM CDT MON OCT 16 2006 VALID 161200Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL TX INTO PARTS OF AR/MS AND WESTERN AL... LARGE UPPER LOW CURRENTLY OVER EASTERN AZ/WESTERN NM IS FORECAST TO BECOME AN OPEN WAVE AND PROPAGATE RAPIDLY NORTHEASTWARD ACROSS TX AND INTO THE MID MS VALLEY BY LATE MONDAY NIGHT. MEANWHILE...VERY STRONG SOUTHERLY LOW LEVEL JET /50-80 KNOTS/ WILL DEVELOP FROM LA INTO MO/IL. THIS WILL RESULT IN A ZONE OF KINEMATIC FIELDS VERY FAVORABLE FOR SEVERE THUNDERSTORMS ON MONDAY FROM EAST TX INTO THE CENTRAL GULF COAST STATES. THE MAIN FORECAST PROBLEM WILL BE THE EVOLUTION OF LOW LEVEL MOISTURE/INSTABILITY AND THE POTENTIAL FOR SURFACE-BASED STORMS. ...ARKLATEX REGION INTO CENTRAL GULF COAST STATES... CURRENTLY RADAR/SATELLITE IMAGERY SHOWS LARGE TROPICAL-LIKE MCS ALONG THE UPPER TX GULF COAST. SEVERAL SUPERCELLS ARE EMBEDDED WITH THIS ACTIVITY...WHICH WILL MOVE ONSHORE BEFORE DAYBREAK. FORECAST SOUNDINGS ACROSS THIS AREA SHOW RAPIDLY STRENGTHENING LOW LEVEL WINDS ACROSS EAST TX AND MUCH OF LA /3KM SR-HELICITY VALUES OF 400-1000 M2/S2 CO-LOCATED WITH DEWPOINTS AOA 70F/...SUGGESTING THAT THREAT FOR ISOLATED TORNADOES AND GUSTY/DAMAGING WINDS WILL ONLY INCREASE THROUGH THE DAY AS MCS MOVES NORTHWARD TOWARD THE MEM AREA. LACK OF STRONG INSTABILITY AND ONLY MARGINAL MID LEVEL LAPSE RATES SUGGEST THAT AREAL COVERAGE OF SEVERE STORMS WILL BE RATHER LOW. HOWEVER...STRENGTH OF WIND FIELDS...TROPICAL AIRMASS...AND APPROACHING UPPER TROUGH INDICATE THE POTENTIAL FOR A FEW TORNADOES DESPITE WEAK INSTABILITY. EXTENT OF THREAT WILL ALSO BE MODULATED BY HOW FAR NORTHEAST THE RICH MOISTURE WILL MAKE IT INTO AR/TN/MS. THIS AREA WILL BE MONITORED DURING LATER UPDATES FOR THE POTENTIAL OF GREATER DESTABILIZATION AND A POSSIBLE UPGRADE. ...CENTRAL-NORTHEAST TX... SOME DAYTIME HEATING WILL BE POSSIBLE ALONG WEST EDGE OF PLUME OF DEEP CLOUDS/MOISTURE...ALLOWING AIR MASS TO BECOME MODERATELY UNSTABLE OVER PARTS OF CENTRAL TX. COOLING TEMPERATURES ALOFT AND STEEPENING LAPSE RATES WILL PROMOTE SCATTERED THUNDERSTORM DEVELOPMENT BY MID AFTERNOON ROUGHLY ALONG A DRT-ACT AXIS. DEEP LAYER EFFECTIVE SHEAR IN THIS REGION WILL SUPPORT SUPERCELL STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. ACTIVITY IS EXPECTED TO SPREAD EAST-NORTHEASTWARD DURING THE EVENING...PROVIDING PARTS OF NORTHEAST TX WITH ANOTHER ROUND OF STRONG/SEVERE STORMS. ..HART/GUYER.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 12:23:08 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 08:23:08 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161225 SWODY1 SPC AC 161223 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0723 AM CDT MON OCT 16 2006 VALID 161300Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM CENTRAL TX INTO THE CENTRAL GULF COAST/MID SOUTH... ...SYNOPSIS... UPPER TROUGH NOW MOVING INTO THE SRN HIGH PLAINS WILL EJECT RAPIDLY TODAY AND TONIGHT AS A NEGATIVELY-TILTED SHORTWAVE TROUGH INTO THE MID SOUTH. AHEAD OF THIS FEATURE...SURFACE LOW CENTER NEAR JCT AT 11Z IS EXPECTED TO LIFT NEWD INTO NERN TX ALONG QUASI-STATIONARY FRONT/TROUGH NOW EXTENDING TOWARDS TKX/CENTRAL AR WITH LOW CENTER EXPECTED TO WEAKEN AS IT LIFTS TOWARDS THE MID SOUTH LATER TONIGHT. A PAIR OF WARM FRONTS HAVE EVOLVED EARLY THIS MORNING ACROSS THE TX/LA COAST WITH PRIMARY MARINE FRONT ANALYZED FROM CENTRAL TX NEWD INTO FAR SERN LA AT 11Z...WHILE SECONDARY WARM FRONT DEVELOPING FROM THE MS COAST NWWD TO NEAR TKX. IN ADDITION...WEAK COLD FRONT IS EXPECTED TO BECOME BETTER DEFINED TO THE S-SW OF NEWD MOVING LOW CENTER...THOUGH FRONT WILL LIKELY MOVE VERY LITTLE AND PERHAPS STALL FROM NERN INTO CENTRAL TX TODAY. THIS WILL LEAVE A VERY MOIST AIR MASS IN PLACE THROUGH THE PERIOD FROM THE TX COAST INTO THE LOWER MS RIVER VALLEY. ...SERN TX INTO THE LOWER MS RIVER VALLEY... SUPERCELLS HAVE REMAINED INTENSE WITH PERSISTENT LOW LEVEL ROTATION FROM THE UPPER TX COAST INTO SRN LA/FAR SRN MS EARLY THIS MORNING... ESPECIALLY NEAR THE MARINE FRONT. AREA VWP/S SUPPORT MODEL GUIDANCE IN SUSTAINING VERY STRONG LLJ ACROSS THIS REGION FOR MUCH OF THE DAY...WITH 11Z WNF PROFILER REVEALING 70 KT WINDS AT 1KM. THIS LEAVES EXTREME LOW LEVEL SHEAR / EVIDENT THIS MORNING WITH OBSERVED 0-1 KM SRH IN EXCESS OF 400 M2/S2 AT KHGX AND KLCH / OVERSPREADING A RICH TROPICAL BOUNDARY LAYER CHARACTERIZED BY SURFACE DEW POINTS IN THE MID/UPPER 70S. WITH DIURNAL HEATING INCREASING POTENTIAL FOR ROTATING STORMS TO ROOT INTO THIS RICH BOUNDARY LAYER...TORNADO THREAT WILL REMAIN ENHANCED OVER THE REGION AND ISOLATED SIGNIFICANT TORNADOES MAY OCCUR. THE LLJ WILL GRADUALLY VEER AND 50-70 KT MAXIMUM IS FORECAST TO LIFT NNEWD INTO THE TN VALLEY LATER THIS EVENING. HOWEVER...CONTINUED FEED OF TROPICAL AIR OFF THE GULF COULD SUSTAIN A TORNADO THREAT ALONG THE GULF COAST FOR MUCH OF THE PERIOD AS FORECAST SOUNDINGS MAINTAIN SFC-1 KM SRH IN EXCESS OF 150 M2/S2 UNDER 40+ KT SSWLY H85 FLOW THROUGH AT LEAST 06Z TONIGHT. ...CENTRAL TX INTO THE MID SOUTH... SEVERE THREAT WILL BECOME MORE CONDITIONAL AWAY FROM THE GULF AS INSTABILITY REMAINS WEAKER. HOWEVER...SURFACE DEWPOINTS NEAR 70F AND EXTREME SHEAR WILL CONTINUE AHEAD OF EJECTING UPPER WAVE AND ASSOCIATED LOW CENTER THROUGH THE PERIOD FROM CENTRAL TX INTO THE MID SOUTH. SMALL LINES AND SUPERCELLS WILL LIKELY EVOLVE THROUGH THE DAY AND MOVE RAPIDLY NEWD...WITH SEVERE THREAT INCREASING WHERE HEATING CAN MIX INTO VERY MOIST SURFACE LAYER. PRIMARY SEVERE THREAT MAY BE FROM LARGE HAIL AS STORMS REMAIN SLIGHTLY ELEVATED ACROSS TX INTO THE EARLY AFTERNOON. HOWEVER...ONCE SUFFICIENT MIXING OCCURS DAMAGING WIND AND ISOLATED TORNADO THREAT WILL LIKEWISE INCREASE. ..EVANS/GUYER.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 16:29:22 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 12:29:22 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 161631 SWODY1 SPC AC 161629 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1129 AM CDT MON OCT 16 2006 VALID 161630Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS THROUGH TONIGHT FROM SE TX INTO THE LOWER MS VALLEY... ...SE TX TO THE LOWER MS VALLEY... A MID LEVEL SHORTWAVE TROUGH OVER ERN NM/W TX WILL EJECT ENEWD OVER THE SRN PLAINS TO AR AND WRN TN/KY BY LATE TONIGHT AS A LARGER SCALE TROUGH DIGS SEWD OVER THE GREAT BASIN. A SURFACE LOW NOW IN NE TX WILL DEVELOP NEWD IN ADVANCE OF THIS EJECTING MID LEVEL WAVE...WHILE THE STRONG LLJ WILL ALSO DEVELOP NEWD FROM LA TOWARD THE TN/OH VALLEYS BY TONIGHT. EXPECT WIDESPREAD CONVECTION TO PERSIST THROUGH THE DAY OVER SE TX AND THE LOWER MS VALLEY ALONG A SURFACE WARM FRONT WHICH IS LIFTING SLOWLY NWD. REGIONAL SOUNDINGS...PROFILERS...AND VWP/S SHOW INTENSE LOW-LEVEL SHEAR /0-1 KM SRH OF 400-700 M2/S2/ WITH THE 50-70 KT LLJ...ESPECIALLY OVER SRN/CENTRAL LA ATTM. DEEP LAYER VERTICAL SHEAR HAS ALSO INCREASED OVER THIS AREA THE PAST SEVERAL HOURS. DESPITE WARM MID LEVEL TEMPERATURES AND POOR LAPSE RATES...BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 70S ARE DRIVING SURFACE-BASED INSTABILITY ALONG AND S OF THE MARINE FRONT. THE MARINE FRONT SHOULD CONTINUE TO LIFT SLOWLY NWD TOWARD THE I-20 CORRIDOR ACROSS LA/MS DURING THE AFTERNOON...WHILE THE LLJ CORE DEVELOPS NEWD INTO MS. THUS...EXPECT THE PRIMARY SUPERCELL TORNADO THREAT AREA TO SHIFT NEWD FROM SE TX/SRN LA THIS MORNING TO CENTRAL/NE LA AND SRN/CENTRAL MS BY LATER THIS AFTERNOON/EVENING. ..THOMPSON/TAYLOR.. 10/16/2006  From swody1 at goshenarc.org Mon Oct 16 20:00:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 16:00:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 162002 SWODY1 SPC AC 162000 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0300 PM CDT MON OCT 16 2006 VALID 162000Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS SE TX TO N-CENTRAL MS AND WRN AL... ...SYNOPSIS... AS WRN CONUS SYNOPTIC TROUGH AMPLIFIES AND MOVES SEWD...STRONG SHORTWAVE TROUGH NOW OVER SRN PLAINS WILL EJECT NEWD...REACHING VICINITY LOWER-MID MS VALLEY BY END OF PERIOD. ASSOCIATED ENHANCED GRADIENTS ALOFT...ALONG WITH LOW LEVEL WAA AND MOISTURE TRANSPORT REGIME...WILL SPREAD ENEWD ACROSS DEEP S IN SUPPORT OF SVR TSTM POTENTIAL. WEAK SFC LOW OVER ARKLATEX REGION SHOULD LIFT NEWD OVER AR. MARINE/WARM FRONT IS ANALYZED ALONG SRN RIM OF LARGE AREA OF PRECIP...FROM SE TX EWD ACROSS CENTRAL LA TO SWRN MS...THEN SEWD TO NEAR COASTAL MS/AL BORDER. THIS FRONT SHOULD LIFT NWD OVER CENTRAL MS AND PORTIONS WRN/SRN AL BEFORE 17/12Z. ...SE TX TO MS/WRN AL... OUTLOOK IS MOST STRONGLY DRIVEN BY SUPERCELLULAR TORNADO THREAT...WITH DAMAGING DOWNDRAFT GUSTS ALSO POSSIBLE FROM EITHER SUPERCELLS OR SMALL BOWS. MARINE FRONT WILL SHIFT SLOWLY NWD ACROSS LA/MS DURING NEXT SEVERAL HOURS...DEMARCATING NRN PORTION OF FAVORABLY BUOYANT ENVIRONMENT. FAVORABLY STRONG LOW LEVEL HODOGRAPHS AND DEEP-LAYER SHEAR ARE EVIDENT BOTH ALONG MARINE FRONT AND WELL SWD INTO WARM SECTOR...AS SAMPLED BY 18Z SIL SOUNDING. REF SPC WWS 830/831...AS WELL AS RELATED MESOSCALE DISCUSSIONS...FOR MORE DETAILED REASONING OF NOWCAST SCENARIO. ASSOCIATED REGIME OF ENLARGED LOW LEVEL HODOGRAPHS...FAVORABLE DEEP-LAYER BULK SHEAR AND AT LEAST MRGL BUOYANCY...IS FCST TO SHIFT ENEWD THIS EVENING AND OVERNIGHT ACROSS MORE OF MS AND SRN/WRN AL. THIS WILL CORRESPOND TO AREAS ALONG AND S OF MARINE FRONT...WHICH SHOULD LIE CLOSE TO 73-74 DEG F SFC ISODROSOTHERM. IN THIS AIR MASS...EXPECT NOCTURNAL/DIABATIC COOLING WILL BE TOO WEAK TO CAUSE ENOUGH STABILIZATION TO RAISE EFFECTIVE PARCELS ABOVE SFC. THEREFORE...GIVEN FCST FAVORABLE SHEAR PROFILES...SUPERCELLS WILL CONTINUE TO DEVELOP...ALONG WITH OCCASIONAL TORNADOES -- A FEW OF WHICH MAY PRODUCE SIGNIFICANT DAMAGE. MODIFIED RAOBS AND MODEL SOUNDINGS SUGGEST MUCAPES UP TO 1000 J/KG AFTER DARK AND 0-1 KM SRH UP TO AROUND 500 J/KG. ..EDWARDS.. 10/16/2006  From swody1 at goshenarc.org Tue Oct 17 00:41:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 16 Oct 2006 20:41:29 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 170043 SWODY1 SPC AC 170041 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0741 PM CDT MON OCT 16 2006 VALID 170100Z - 171200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE CENTRAL GULF STATES... ...CENTRAL GULF STATES... SFC LOW CONTINUES TO LIFT NEWD ACROSS NERN AR IN RESPONSE TO EJECTING UPPER SHORTWAVE TROUGH. JUST DOWNSTREAM...TRUE WARM SECTOR RECOVERY HAS STRUGGLED TO RETURN NWD HOWEVER AS STRONG LOW LEVEL WARM ADVECTION AND WIDESPREAD PRECIPITATION MAINTAIN STABLE BOUNDARY LAYER AIRMASS ACROSS THE NERN HALF OF AL INTO NRN MS. ALTHOUGH INTENSE LOW LEVEL SHEAR EXISTS ALONG/NORTH OF BOUNDARY...UPDRAFT STRENGTH IS SOMEWHAT LACKING DUE TO MEAGER INSTABILITY. HOWEVER...JUST SOUTH OF THE WARM FRONT SUFFICIENT INSTABILITY EXISTS FOR ROBUST UPDRAFTS WHICH AT TIMES APPEAR TO TAKE ADVANTAGE OF STRONG LOW LEVEL SHEAR...AS EVIDENT BY PERIODIC TORNADIC SIGNATURES WITH NWD-MOVING SUPERCELLS WELL AHEAD OF ADVANCING COLD FRONT. THESE TRENDS WILL CONTINUE THROUGH THE EVENING WITH THE MOST PRONOUNCED TORNADO THREAT EXPECTED TO PERSIST WITHIN MORE DISCRETE SUPERCELLS AHEAD OF FORCED LINE OF STORMS THAT IS MOVING EWD ACROSS LA INTO WRN MS. SHEAR PROFILES ARE QUITE IMPRESSIVE ACROSS MUCH OF THE REGION WHICH FAVOR RAPID...AND POSSIBLY STRONG...TORNADIC DEVELOPMENT WITH ANY SUSTAINED SUPERCELL STRUCTURES. OTHERWISE...GUSTY WINDS MAY ACCOMPANY THE FORCED LINE OF STORMS AS THEY PROGRESS EWD DURING THE OVERNIGHT HOURS. ...ELSEWHERE... 00Z SOUNDING FROM GJT SUPPORTS ONGOING CONVECTIVE ACTIVITY ALONG COLD FRONT AS IT SURGES SEWD ACROSS THE CNTRL ROCKIES TONIGHT. STEEP LAPSE RATE ENVIRONMENT WILL GRADUALLY WANE WITH LOSS OF BOUNDARY LAYER HEATING AND UPDRAFT STRENGTH SHOULD ALSO REFLECT THIS INSTABILITY LOSS WITH GRADUALLY WEAKENING TRENDS AFTER SUNSET. ..DARROW.. 10/17/2006  From swody1 at goshenarc.org Fri Oct 20 12:44:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 08:44:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201246 SWODY1 SPC AC 201244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT FRI OCT 20 2006 VALID 201300Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NJ INTO SRN/ERN NEW ENGLAND... ...SYNOPSIS... BROAD CYCLONIC FLOW WILL PREVAIL OVER THE LWR 48 THIS PERIOD... DOWNSTREAM FROM E PACIFIC RIDGE. FAST-MOVING SHORTWAVE TROUGH NOW OVER THE UPR OH VLY EXPECTED TO AMPLIFY INTO A POTENT NEGATIVE-TILT IMPULSE OVER SRN NEW ENGLAND LATER TODAY AS SYSTEM CONTINUES TO MERGE WITH SHORTWAVE THAT CROSSED THE MID MS VLY YESTERDAY. FARTHER W...STRONG SPEED MAX NOW ENTERING ID SHOULD ALSO FURTHER AMPLIFY AS IT CONTINUES SE ACROSS THE CNTRL RCKYS LATER TODAY/EARLY SATURDAY. AT THE SFC...LOW NOW CONSOLIDATING IN S CNTRL PA EXPECTED TO STRENGTHEN SUBSTANTIALLY LATER TODAY/TONIGHT AS IT CROSSES SRN NEW ENGLAND AND THEN TURNS MORE NEWD ACROSS DOWNEAST ME. IN THE PLAINS...MT COLD FRONT SHOULD ACCELERATE SE AND OVERTAKE LEE TROUGH OVER S CNTRL NEB/NRN AND WRN KS. ...NJ INTO SRN/ERN NEW ENGLAND... OVERNIGHT SHOWERS IN THE MID ATLANTIC REGION APPEAR TO HAVE BEEN ASSOCIATED WITH LEAD IMPULSE BEING ABSORBED INTO STRONGER SHORTWAVE APPROACHING FROM THE OH VLY. THIS CONVECTION HAS SERVED TO MOISTEN THE BOUNDARY LAYER...AND SHOULD CONTINUE NE ACROSS SRN NEW ENGLAND AND OFF THE MID ATLANTIC CST LATER TODAY. IN WAKE OF THE SHOWERS...MODEST SURFACE HEATING SHOULD OCCUR AHEAD OF COLD FRONT ASSOCIATED WITH STRENGTHENING PA SFC LOW. WHILE MID LEVEL LAPSE RATES LIKELY WILL REMAIN WEAK AND SURFACE HEATING WILL BE LIMITED...COMBINATION OF EVEN MODERATE DIURNAL HEATING WITH STRONG DPVA...FRONTAL ASCENT AND MOIST LOW LEVEL ENVIRONMENT SHOULD SUPPORT DEVELOPMENT OF LOW-TOPPED CONVECTION/ POSSIBLE TSTMS ALONG AND JUST AHEAD OF COLD FRONT. WHILE THE STORMS MAY FORM AS FAR W AS ERN PA OR NJ...MORE SUBSTANTIAL ACTIVITY MAY NOT OCCUR UNTIL FRONT PASSES THE NYC AREA EARLY IN THE AFTN. RAPIDLY STRENGTHENING LOW TO MID LEVEL WIND FIELD /WITH 500 MB SPEEDS INCREASING TO AOA 60 KTS/ AND LINEAR FORCING MAY SUPPORT DEVELOPMENT OF A NARROW SQLN...WITH EMBEDDED SMALL SCALE BOWS/ ROTATING STORMS PRODUCING HIGH WIND AND POSSIBLY ONE OR TWO TORNADOES. THIS THREAT MAY REACH INTO THE CSTL ME AREA BY EVENING AS UPR SYSTEM ASSUMES A NEGATIVE TILT AND SFC LOW DEEPENS NEWD. ...CNTRL PLNS... SURFACE HEATING...CONVERGENCE ALONG LEE TROUGH/COLD FRONT AND ASCENT ASSOCIATED WITH APPROACHING/AMPLIFYING UPR TROUGH MAY SUPPORT THE DEVELOPMENT OF SCATTERED HIGH-BASED STORMS FROM SRN/CNTRL NEB INTO WRN/NRN KS. DEEPLY MIXED ENVIRONMENT WITH MODERATE UNIDIRECTIONAL WNWLY FLOW MAY SUPPORT MARGINALLY SEVERE HAIL AND GUSTY WINDS FOR A BRIEF PERIOD EARLY THIS EVENING. ..CORFIDI/CROSBIE.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 16:02:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 12:02:13 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201603 SWODY1 SPC AC 201602 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1102 AM CDT FRI OCT 20 2006 VALID 201630Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NJ INTO SRN/ERN NEW ENGLAND... ...NJ INTO SRN/ERN NEW ENGLAND... SURFACE LOW DEEPENING UNDERWAY ACROSS ERN PA IN RESPONSE TO THE VIGOROUS UPPER S/WV TROUGH NOW INTO WRN PA. A STRONGLY FORCED LINE OF LOW TOPPED CONVECTION HAS DEVELOPED FROM THE SURFACE LOW SWD TO DCA AT 15Z VICINITY OF THE COLD FRONT. GENERALLY WEAK LAPSE RATES AND THE EXPECTED LITTLE SURFACE HEATING AHEAD OF THE LINE WILL LIMIT INSTABILITY AVAILABLE FOR DEEP CONVECTION TODAY. AS THE 90 PLUS KT 500 MB WIND MAX AND MID LEVEL COOLING ROTATE ACROSS NJ INTO SRN ENGLAND LATER THIS AFTERNOON...ALONG WITH THE RAPIDLY DEEPENING SURFACE LOW...SURFACE WINDS ASSOCIATED WITH THE CURRENT LINE OF CONVECTION WILL INCREASE ALONG WITH POTENTIAL FOR DAMAGING WINDS. BY 19Z THE LINE WILL BE PASSING THRU NYC SWD TO OFFSHORE NJ. WINDS AT ALL LEVELS WILL CONTINUE TO INCREASE THRU THE AFTERNOON AND EVENING WITH SURFACE LOW DEEPENING NEWD THRU INTERIOR NEW ENGLAND. THE POTENTIAL FOR DAMAGING WINDS WITH THE LOW TOPPED LINE OF CONVECTION EXPECTED TO SPREAD NEWD AHEAD OF SURFACE LOW...WITH GREATEST POTENTIAL VICINITY OF WARM FRONT. THE WARM FRONT CURRENTLY EXTENDS FROM LOW IN ERN PA NEWD ACROSS SERN NY/WRN MA TO VICINITY PWM. FRONT WILL CONTINUE TO SHIFT NWD INTO COASTAL AREAS OF MAINE DURING THE AFTERNOON PRIOR TO THE PASSAGE OF CONVECTIVE LINE. SINCE MLCAPE IS EXPECTED TO BE NO GREATER THAN 200 J/KG ANY DAMAGING WIND THREAT WILL BE PRIMARILY DRIVEN BY THE DOWNWARD TRANSFER OF THE STRONG WIND FIELDS WITH THE TROUGH AND INTENSIFYING SURFACE LOW ..HALES/GUYER.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 19:36:54 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 15:36:54 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201938 SWODY1 SPC AC 201937 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0237 PM CDT FRI OCT 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF CNTRL/SRN NEW ENGLAND... 19Z SFC ANALYSIS PLACES A 987 MB LOW VCNTY KPSF WITH A WARM FRONT LOCATED ACROSS SRN VT AND NH INTO DOWNEAST MAINE. TO THE S...A SHARP COLD FRONT WAS SWEEPING EWD WITH AN ASSOCD LINE OF CONVECTION. THE LOW WILL CONTINUE TO DEEPEN THIS EVENING WHILE MOVING NEWD INTO CNTRL MAINE. THE TRAILING FRONT WILL MOVE ACROSS CNTRL/SRN NEW ENGLAND AND OFFSHORE LATER THIS AFTERNOON. STRONGLY FORCED LOW-TOPPED SQUALL LINE WAS MOVING ENEWD AT 40 KTS AND IS EXTRAPOLATED TO CNTRL MASS...CNTRL CT AND ERN LONG ISLAND BY 21Z AND INTO SERN MASS/KBOS BETWEEN 22-23Z. RECENT SOUNDING FROM A DESCENDING AIRCRAFT INTO KPHL JUST BEHIND THE SQUALL LINE COUPLED WITH KDIX 88D VWP SUGGEST THAT 50 KT WINDS WERE DOWN TO AROUND 1 KM AGL. GIVEN STRENGTHENING OF THE ATTENDANT UPPER SYSTEM AND CORRESPONDING ACCELERATION OF WIND FIELDS...CONVECTION WILL CONTINUE TO HAVE THE POTENTIAL FOR DAMAGING WIND GUSTS THROUGHOUT CNTRL/SRN NEW ENGLAND LATE AFTN/EARLY EVE...PARTICULARLY AT HIGHER ELEVATIONS. ..RACY.. 10/20/2006  From swody1 at goshenarc.org Fri Oct 20 19:48:46 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 15:48:46 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 201950 SWODY1 SPC AC 201948 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 0248 PM CDT FRI OCT 20 2006 VALID 202000Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF CNTRL/SRN NEW ENGLAND... 19Z SFC ANALYSIS PLACES A 987 MB LOW VCNTY KPSF WITH A WARM FRONT LOCATED ACROSS SRN VT AND NH INTO DOWNEAST MAINE. TO THE S...A SHARP COLD FRONT WAS SWEEPING EWD WITH AN ASSOCD LINE OF CONVECTION. THE LOW WILL CONTINUE TO DEEPEN THIS EVENING WHILE MOVING NEWD INTO CNTRL MAINE. THE TRAILING FRONT WILL MOVE ACROSS CNTRL/SRN NEW ENGLAND AND OFFSHORE LATER THIS AFTERNOON. STRONGLY FORCED LOW-TOPPED SQUALL LINE WAS MOVING ENEWD AT 40 KTS AND IS EXTRAPOLATED TO CNTRL MASS...CNTRL CT AND ERN LONG ISLAND BY 21Z AND INTO SERN MASS/KBOS BETWEEN 22-23Z. RECENT SOUNDING FROM A DESCENDING AIRCRAFT INTO KPHL JUST BEHIND THE SQUALL LINE COUPLED WITH KDIX 88D VWP SUGGEST THAT 50 KT WINDS WERE DOWN TO AROUND 1 KM AGL. GIVEN STRENGTHENING OF THE ATTENDANT UPPER SYSTEM AND CORRESPONDING ACCELERATION OF WIND FIELDS...CONVECTION WILL CONTINUE TO HAVE THE POTENTIAL FOR DAMAGING WIND GUSTS THROUGHOUT CNTRL/SRN NEW ENGLAND LATE AFTN/EARLY EVE...PARTICULARLY AT HIGHER ELEVATIONS. ..RACY.. 10/20/2006  From swody1 at goshenarc.org Sat Oct 21 00:21:24 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 20 Oct 2006 20:21:24 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210021 SWODY1 SPC AC 210020 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0720 PM CDT FRI OCT 20 2006 VALID 210100Z - 211200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... COMPACT UPPER LOW WILL MOVE ENEWD ACROSS NEW ENGLAND THROUGH THE REMAINDER OF THE PERIOD...ALONG WITH AN ASSOCIATED THREAT FOR A FEW LIGHTNING STRIKES EMBEDDED WITHIN AREA OF WIDESPREAD PRECIPITATION. FURTHER W...A SECOND UPPER TROUGH WILL CONTINUE DIGGING SSEWD ACROSS THE ROCKIES THROUGH THE END OF THE PERIOD. A LARGE AREA OF PRECIPITATION -- WITH ISOLATED/EMBEDDED THUNDERSTORMS -- IS OCCURRING WITHIN CYCLONIC FLOW AROUND THIS FEATURE FROM WRN MT SEWD ACROSS WY AND CO AND INTO THE CENTRAL PLAINS. THOUGH LIGHTNING SHOULD DIMINISH WITH THE LOSS OF DIURNAL HEATING...A FEW STRIKES MAY PERSIST THROUGH 21/12Z -- PARTICULARLY ACROSS KS AND VICINITY WITHIN AREA OF WARM ADVECTION ASSOCIATED WITH NOCTURNAL LOW-LEVEL JET. ..GOSS.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 05:34:55 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 01:34:55 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 210536 SWODY1 SPC AC 210534 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1234 AM CDT SAT OCT 21 2006 VALID 211200Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... LARGE UPPER TROUGH IS FORECAST TO MOVE SLOWLY ACROSS THE CENTRAL CONUS THIS PERIOD...ACCOMPANIED BY 100 KT MID-LEVEL JET. AT THE SURFACE...FRONT NOW EXTENDING FROM FL INTO THE NRN GULF SHOULD RETREAT NWD INTO THE GULF COAST REGION DURING THE FIRST HALF OF THE PERIOD. MEANWHILE...SECOND FRONT -- WHICH IS FORECAST TO SURGE SWD ACROSS THE PLAINS/EWD ACROSS THE MS VALLEY -- SHOULD OVERTAKE THE GULF COAST FRONT THROUGH THE LATTER HALF OF THE PERIOD. ...GULF COAST REGION... WARM MOIST BOUNDARY LAYER SHOULD SPREAD ONSHORE OVER THE GULF COAST REGION DURING THE FIRST HALF OF THE PERIOD...AS WEAKENING FRONT RETREATS NWD AHEAD OF SECOND BOUNDARY SURGING SEWD ACROSS THE CENTRAL CONUS. DESPITE BOUNDARY-LAYER DEWPOINTS IN THE LOW 70S...WEAK LAPSE RATES WITHIN THE MOIST TROPICAL AIRMASS S OF RETREATING BOUNDARY SHOULD HINDER SIGNIFICANT WARM SECTOR DESTABILIZATION. IN ADDITION...THIS REGION WILL REMAIN S OF THE ANTICYCLONICALLY-CURVED MID/UPPER JET. RESULTING SUBSIDENCE COMBINED WITH THE GENERAL LACK OF FAVORABLE INSTABILITY WILL LIKELY LIMIT THE POTENTIAL FOR VIGOROUS UPDRAFTS. NONETHELESS...WITH 30 TO 40 KT WLY MID-LEVEL FLOW YIELDING DEEP-LAYER SHEAR OTHERWISE SUFFICIENT FOR ORGANIZED STORMS...WILL MAINTAIN A LOW-PROBABILITY SEVERE THREAT ACROSS THIS REGION. ..GOSS/TAYLOR.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 12:44:45 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 08:44:45 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211246 SWODY1 SPC AC 211244 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0744 AM CDT SAT OCT 21 2006 VALID 211300Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... BROAD UPR TROUGH WILL PERSIST OVER THE CNTRL AND ERN U.S. THROUGH SUNDAY AS RIDGE PROGRESSES TO THE PAC NW CST. SHORTWAVE IMPULSE NOW OVER CO SHOULD MOVE E ACROSS THE OZARKS AND MID MS VLY LATER TODAY/ TONIGHT AS ADDITIONAL SPEED MAXIMA DROP S INTO THE NRN AND CNTRL RCKYS. AT LOWER LEVELS...WRN PART OF FRONT EXTENDING FROM N CNTRL FL ACROSS THE NRN GULF OF MEXICO IS RETURNING NWD AS A WARM FRONT OVER THE NWRN GULF. THIS BOUNDARY SHOULD REACH CSTL SECTION OF SE TX AND SRN LA LATER TODAY AS COLD FRONT ASSOCIATED WITH CO DISTURBANCE ACCELERATES SE ACROSS THE SRN PLNS. THE COLD FRONT SHOULD OVERTAKE THE GULF BOUNDARY OVER THE LWR MS VLY DURING THE LATTER HALF OF THE PERIOD. ...GLF CST RGN... LATEST OBSERVATIONS SHOW WARM MOIST AIR SPREADING NNW ACROSS THE FAR NWRN GULF TOWARD THE MIDDLE AND UPR TX GULF CST. DEWPOINTS IN THE LOW 70S SHOULD LIFT N INTO THE IMMEDIATE CSTL SECTIONS OF SE TX LATER TODAY. ALONG WITH SURFACE HEATING...THIS WILL RESULT IN SOME LOW LEVEL DESTABILIZATION. MID LEVEL LAPSE RATES WILL...HOWEVER... REMAIN WEAK AS REGION WILL BE ON EQUATORWARD SIDE OF CYCLONICALLY- CURVED UPR JET. WHILE MODEST DESTABILIZATION AND WEAK FRONTAL UPLIFT MAY YIELD A FEW AFTN STORMS ALONG THE CSTL PLAIN...THE STRONGEST ACTIVITY SHOULD REMAIN OFFSHORE. LOW LEVEL SHEAR SHOULD REMAIN WEAK...BUT COUPLED WITH HIGH SURFACE DEWPOINTS...SETUP MAY SUPPORT AN ISOLATED TORNADO OR TWO. LATER THIS AFTN INTO TONIGHT...ADDITIONAL STORMS LIKELY WILL FORM ALONG AND BEHIND AFOREMENTIONED COLD FRONT AS IT ACCELERATES SE ACROSS E TX/LA AND MS. MUCH OF THIS ACTIVITY WILL EITHER BE ELEVATED OR WILL QUICKLY BECOME SO AS THE BOUNDARY UNDERCUTS DEVELOPING UPDRAFTS. PRESENCE OF 40+ KT DEEP WLY SHEAR ON SRN FRINGE OF CNTRL PLNS TROUGH AND RICH MOISTURE MAY...NEVERTHELESS ...SUPPORT A FEW CELLS WITH STRONG SURFACE WINDS DESPITE RELATIVELY WEAK FORCING FOR ASCENT. ..CORFIDI/TAYLOR.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 16:06:11 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 12:06:11 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211607 SWODY1 SPC AC 211606 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1106 AM CDT SAT OCT 21 2006 VALID 211630Z - 221200Z ...NO SVR TSTM AREAS FORECAST... BROAD UPPER TROUGH DOMINATES MUCH OF CONUS ACCOMPANIED BY A STRONG POLAR JET SHIFTING EWD ACROSS SRN/CENTRAL PLAINS TO OH VALLEY BY SUN AM. STALLED FRONTAL ZONE ALONG/JUST OFFSHORE GULF COAST WILL MOVE INLAND THIS AFTERNOON UPR TX/LA COAST. LOW/MID LEVEL WARM ADVECTION COUPLED WITH TROPICAL MOISTURE FLUX CURRENTLY RESULTING IN ELEVATED CONVECTION SPREADING NEWD ACROSS SERN TX. NEXT COLD FRONT CURRENTLY MOVING THRU OK/NWRN TX WILL CONTINUE SEWD TO OFFSHORE MUCH OF TX COAST BY 12Z SUN. WHILE DEEP LAYER SHEAR OF 40KTS AND MLCAPES CLIMBING TO NEAR 2000 J/KG COASTAL AREAS SERN TX/SRN LA SUFFICIENT FOR A SEVERE THUNDERSTORM THREAT.. THE WEAK LAPSE RATES AND MARGINAL LOW LEVEL SHEAR PRECLUDES MORE THAN A LOW RISK OF ISOLATED ROTATING STORMS. WARM...MOIST ADVECTION WILL SPREAD THUNDERSTORMS EWD ACROSS CENTRAL GULF COAST STATES THRU TONIGHT. ADDITIONALLY WITH THE COLD FRONT ENCOUNTERING THE GULF MOISTURE LATER TONIGHT...FRONTAL CONVERGENCE SHOULD FOCUS ADDITIONAL STORM DEVELOPMENT SRN TX INTO LA PRIOR TO MOVING OFFSHORE BY SUN AM. ..HALES/GUYER.. 10/21/2006  From swody1 at goshenarc.org Sat Oct 21 19:36:07 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 15:36:07 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 211937 SWODY1 SPC AC 211935 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0235 PM CDT SAT OCT 21 2006 VALID 212000Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...GULF COASTAL STATES... AT 19Z...A MARINE WARM FRONT WAS LOCATED ALONG THE IMMEDIATE OFFSHORE WATERS OF THE UPPER TX COAST AND LA. WARM/MOIST ADVECTION ABOVE THE RESIDUAL CONTINENTAL POLAR BOUNDARY LAYER INLAND WAS RESULTING IN ELEVATED TSTMS...LIKELY ROOTED JUST ABOVE 800 MB PER RUC SOUNDINGS. CLOUD-BEARING SHEAR WAS SUFFICIENT FOR STORMS TO ATTAIN BRIEF SUPERCELLULAR CHARACTERISTICS...BUT MEAGER LAPSE RATES /WARM NOSE AROUND H7/ WILL LIKELY CONTINUE TO BE A DETRIMENT TO ORGANIZED ROBUST STORMS. THE SMALL MCS WILL LIKELY EXPAND ENEWD ACROSS THE LWR MS VLY AND TOWARD THE SERN STATES BY 12Z SUNDAY. VEERING MEAN LAYER FLOW WILL NOT BE FAVORABLE FOR MARITIME TROPICAL AIR TO SURGE NWD AT LOCATIONS E OF THE MS RVR. AS A RESULT...THERMODYNAMIC PROFILES DO NOT APPEAR SUPPORTIVE FOR ORGANIZED SEVERE WEATHER. OVERNIGHT...OTHER STORMS ARE LIKELY TO FORM ALONG/AHEAD OF THE SEWD MOVING COLD FRONT ACROSS THE UPPER TX COAST AND SPREAD EWD INTO CNTRL/SRN LA. HERE...SLIGHTLY MORE UNSTABLE BOUNDARY LAYER WILL EXIST ALONG THE IMMEDIATE COAST AND ISOLD TSTMS MAY BECOME ROOTED CLOSER TO THE SFC AND PRODUCE DAMAGING WINDS. THE MAJORITY OF THE STORMS SHOULD REMAIN SUB-SEVERE...HOWEVER. ..RACY.. 10/21/2006  From swody1 at goshenarc.org Sun Oct 22 00:27:42 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sat, 21 Oct 2006 20:27:42 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220029 SWODY1 SPC AC 220027 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0727 PM CDT SAT OCT 21 2006 VALID 220100Z - 221200Z ...NO SVR TSTM AREAS FORECAST... ...CENTRAL GULF COAST REGION... MOIST BOUNDARY LAYER AIRMASS CONTINUES WORKING NWD INTO THE CENTRAL GULF COAST REGION...AHEAD OF WEAK SRN STREAM SHORT-WAVE TROUGH AND ASSOCIATED AREA OF SHOWERS AND THUNDERSTORMS NOW CROSSING THE LOWER MS VALLEY. DESPITE UPPER 60S TO LOW 70S DEWPOINTS NOW OVER SRN LA...EVENING RAOBS INDICATE A SURFACE-BASED STABLE LAYER REMAINS ACROSS MOST OF THE REGION AWAY FROM THE IMMEDIATE COAST. FURTHER...SOUNDINGS REVEAL WEAK LAPSE RATES ACROSS SERN LA...WHICH IS LIMITING DEGREE OF INSTABILITY. THEREFORE...HAIL THREAT IS LIKELY TO REMAIN MINIMAL ACROSS THIS REGION. SOUNDINGS AND AREA VWPS DO INDICATE SUFFICIENT VEERING WITH HEIGHT/DEEP-LAYER SHEAR FOR ORGANIZED/ROTATING STORMS. ONE STORM JUST S OF THE S CENTRAL LA COAST DID SHOW SUPERCELL CHARACTERISTICS OVER THE PAST HOUR...AND ADDITIONAL ROTATING STORMS ARE POSSIBLE -- PARTICULARLY FROM SERN LA THIS EVENING...AND THEN EWD ACROSS SRN MS/SRN AL/THE WRN FL PANHANDLE OVERNIGHT. THEREFORE...WILL MAINTAIN A SMALL/LOW-PROBABILITY SEVERE THREAT AREA...WHERE A LOCALLY-DAMAGING GUST OR A BRIEF/WEAK TORNADO WILL BE POSSIBLE. ..GOSS.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 05:42:14 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 01:42:14 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 220543 SWODY1 SPC AC 220541 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1241 AM CDT SUN OCT 22 2006 VALID 221200Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... LARGE UPPER TROUGH WILL CONTINUE MOVING SLOWLY EWD ACROSS THE CENTRAL AND ERN CONUS THIS PERIOD...ACCOMPANIED BY A LARGE/STRONG CYCLONIC JET STREAK. AT THE SURFACE...ASSOCIATED BAROCLINIC ZONE WILL CONTINUE SURGING SEWD INTO THE GULF OF MEXICO AND EWD ACROSS THE APPALACHIANS TOWARD THE ATLANTIC COAST THROUGH THE DAY. BY THE END OF THE PERIOD...THE FRONT SHOULD EXTEND FROM WELL OFF THE ATLANTIC COAST SWWD ACROSS CENTRAL FL AND INTO THE SRN GULF OF MEXICO. SHOWERS AND A FEW THUNDERSTORMS MAY BE ONGOING AT THE START OF THE PERIOD OVER THE SOUTHEAST AHEAD OF THIS FRONT...AND ISOLATED CONVECTION MAY DEVELOP NWD ALONG THE CAROLINA COAST AHEAD OF THE FRONT DURING THE DAY. HOWEVER...LACK OF INSTABILITY SUGGESTS THAT STORMS SHOULD REMAIN GENERALLY WEAK. BEST CHANCE FOR A STRONGER STORM WILL LIKELY EXIST OVER SRN GA/NRN FL...BUT ATTM ANY SEVERE POTENTIAL APPEARS TOO LOW TO WARRANT THE INCLUSION OF A THREAT AREA. ..GOSS/TAYLOR.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 12:46:17 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 08:46:17 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221247 SWODY1 SPC AC 221245 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0745 AM CDT SUN OCT 22 2006 VALID 221300Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS/FORECAST... BROAD...DEEP CLOSED LOW CENTERED N OF LK SUPERIOR WILL DOMINATE THE ERN TWO THIRDS OF THE NATION THIS PERIOD AS DEAMPLIFYING RIDGE PROGRESSES E INTO SW CANADA AND THE INTERIOR PAC NW. BAND OF FAST W/WSWLY FLOW ON SRN EDGE OF LOW WILL PREVAIL TODAY FROM THE LWR MS/TN VLY TO THE MID AND S ATLANTIC CSTS. AT LOWER LEVELS...ASSOCIATED COLD FRONT WILL CONTINUE SE INTO THE GULF OF MEXICO AND E ACROSS THE APPALACHIANS TOWARD THE ATLANTIC COAST THROUGH THE DAY. BY EARLY MONDAY THE FRONT SHOULD CURVE CYCLONICALLY FROM CAPE COD TO WELL OFF THE MID ATLANTIC COAST...AND THEN SW ACROSS CNTRL FL INTO THE SRN GULF OF MEXICO. FARTHER S... WEAK WARM FRONT NOW OVER THE FL PANHANDLE AND NERN GULF SHOULD CONTINUE TO WEAKEN AS IT LIFTS SLOWLY NE INTO NRN FL AND S GA. SHOWERS AND A FEW THUNDERSTORMS LIKELY WILL PERSIST ALONG AND AHEAD OF COLD FRONT FROM THE N CNTRL GULF E/NE INTO PARTS OF GA AND N FL. ELEVATED STORMS MAY ALSO LINGER FOR SOME TIME TODAY ABOVE FRONTAL SURFACE OVER DEEP S TX. MORE ISOLATED ACTIVITY MAY DEVELOP NWD ALONG THE SC CST...AND IN DPVA/JET EXIT REGION OVER WRN NY/PA. STORMS MAY ALSO FORM OFF THE CAROLINA CST THIS EVENING. LIMITED DEGREE OF INSTABILITY...AND WEAK CONVERGENCE/LARGE SCALE FORCING FOR ASCENT...SUGGEST THAT UPDRAFTS IN MOST AREAS WILL REMAIN FAIRLY WEAK. THE BEST CHANCE FOR STRONGER STORMS SHOULD EXIST OVER SRN GA/NRN FL...AND OVER DEEP S TX....MAINLY BETWEEN NOW AND LATE AFTERNOON. VEERING LOW LEVEL FLOW WITH TIME SHOULD RESULT IN A DIMINISHING THREAT FOR LOW LEVEL STORM ROTATION WITH ANY STRONGER UPDRAFTS IN THE FL PANHANDLE THIS MORNING. ..CORFIDI/TAYLOR.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 16:04:42 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 12:04:42 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221605 SWODY1 SPC AC 221604 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1104 AM CDT SUN OCT 22 2006 VALID 221630Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...DISCUSSION/SYNOPSIS... LONGWAVE UPPER TROUGH WILL REMAIN OVER THE CNTRL/ERN U.S. WITH UPPER LOW CENTER SHIFTING SWD ACROSS WRN ONTARIO INTO THE NRN GREAT LAKES. LEAD UPPER SHORTWAVE TROUGH WILL SHIFT EWD ACROSS THE ERN GREAT LAKES WITH ASSOCIATED SURFACE LOW PRESSURE TROUGH ENHANCING LOW LEVEL CONVERGENCE OVER LAKE ERIE/ONTARIO. GIVEN MINIMAL LAKE INDUCED CONVECTIVE INSTABILITY...AN ISOLATED LIGHTING STRIKE CANNOT BE RULED OUT. TO THE SOUTH...A COLD FRONT WILL BE THE FOCUS FOR SCATTERED STORMS FROM SRN GA/NRN FL INTO SC. ...SRN GA/NRN FL... CONVECTION WILL FOCUS ALONG A WEAK FRONTAL BOUNDARY THAT WILL GRADUALLY SHIFT SWD ACROSS SRN GA/NRN FL. SURFACE HEATING AND WEAK CONVERGENCE WILL ALLOW FOR SCATTERED STORMS TO PERSIST/REDEVELOP ALTHOUGH INSTABILITY WILL REMAIN RELATIVELY WEAK. SHEAR PROFILES SOUTH OF THE COLD FRONT WILL REMAIN MODEST AT BEST WITH MAIN WIND CORE ALOFT WELL NORTH OF THE FRONT. THUS...SEVERE UNLIKELY ALTHOUGH STEEP LOW LEVEL LAPSE RATES MAY ALLOW FOR LOCALLY STRONG WIND GUSTS. ..JEWELL/HALES.. 10/22/2006  From swody1 at goshenarc.org Sun Oct 22 19:51:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 15:51:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 221953 SWODY1 SPC AC 221951 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0251 PM CDT SUN OCT 22 2006 VALID 222000Z - 231200Z ...NO SVR TSTM AREAS FORECAST... ...SE ATLANTIC COAST AND NRN FL... AS THE PRIMARY UPPER TROUGH SWINGS THROUGH THE GRTLKS REGION...OVERALL DEEP LAYER FLOW REGIME WAS BECOMING WLY ACROSS THE COLD FRONT. POOR LAPSE RATES ALOFT AND INCREASINGLY UNFAVORABLE KINEMATIC REGIME HAVE CONTRIBUTED TO WEAKENING TREND OF THE TSTMS ACCOMPANYING THE FRONT THIS AFTN. THIS TREND SHOULD CONTINUE THIS EVE. FARTHER S...PWAT VALUES ARE LOWER THAN SATURDAY WHERE MINIMAL CONVECTION OCCURRED ALONG THE SEABREEZES. OTHER THAN ISOLD SHOWERS...THE LIGHTNING THREAT ACROSS CNTRL/SRN FL APPEARS MINIMAL /LESS THAN 10 PERCENT PROBABILITY/. ...LWR GRTLKS... CONSIDERABLE CONVECTION ASSOCD WITH AN UPR SHORT WAVE TROUGH AND ATTENDANT COLD FRONT CONTINUES TO ROTATE NEWD ACROSS THE LWR GRTLKS REGION. THERMODYNAMIC PROFILES REMAIN MARGINALLY FAVORABLE FOR ISOLD LIGHTNING STRIKES WITH THE STRONGER CONVECTIVE ELEMENTS. AN ISOLD STRIKE OR TWO COULD ALSO ACCOMPANY ANY LAKE-ENHANCED CONVECTION THAT DEVELOPS LATER TONIGHT. ..RACY.. 10/22/2006  From swody1 at goshenarc.org Mon Oct 23 00:50:23 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 22 Oct 2006 20:50:23 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 230051 SWODY1 SPC AC 230049 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0749 PM CDT SUN OCT 22 2006 VALID 230100Z - 231200Z ...NO SVR TSTM AREAS FORECAST... A BROAD UPPER-LEVEL CNTRL AND ERN U.S. TROUGH WILL BE IN PLACE TONIGHT AS A COLD FRONT MOVES SEWD ACROSS FL AND THE ERN SEABOARD. MOISTURE...INSTABILITY AND CONVERGENCE APPEAR SUFFICIENT FOR THUNDERSTORM ACTIVITY ALONG THE BOUNDARY IN SRN GA AND NRN FL. HOWEVER...WEAK LARGE-SCALE ASCENT SHOULD KEEP THE ACTIVITY VERY ISOLATED THIS EVENING. ELSEWHERE...A FEW WEAK THUNDERSTORMS SHOULD CONTINUE FOR 1 TO 2 MORE HOURS IN ERN PA ASSOCIATED WITH STRONG LIFT FROM BANDS OF ASCENT AHEAD OF THE UPPER-TROUGH. ISOLATED THUNDERSTORMS MAY ALSO OCCUR OVER THE WARM WATERS OF LAKE ERIE AND ONTARIO THIS EVENING. ..BROYLES.. 10/23/2006  From swody1 at goshenarc.org Wed Oct 25 05:11:51 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 25 Oct 2006 01:11:51 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 250515 SWODY1 SPC AC 250514 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1214 AM CDT WED OCT 25 2006 VALID 251200Z - 261200Z ...NO SVR TSTM AREAS FORECAST... ...SRN AND CNTRL PLAINS... A NRN ROCKIES UPPER-LEVEL TROUGH WILL DIG SEWD AND CLOSE-OFF OVER THE FOUR CORNERS REGION TODAY. IN RESPONSE...A SFC LOW WILL DEEPEN OVER SE CO AS MOISTURE ADVECTION INCREASES IN THE SRN AND CNTRL PLAINS QUICKLY TRANSPORTING LOWER 60 F SFC DEWPOINTS NWD ACROSS NORTH TX AND WRN OK BY LATE THIS AFTERNOON. THUNDERSTORM DEVELOPMENT MAY OCCUR ALONG A STRONGLY CONVERGENT WARM FRONT EXTENDING EWD FROM THE SFC LOW ACROSS KS INTO NRN MO. FORECAST SOUNDINGS ALONG THE WARM FRONT THIS AFTERNOON SHOW STRONG VERTICAL SHEAR AND RELATIVELY COLD TEMPS ALOFT SUGGESTING HAIL WILL BE POSSIBLE WITH THE BETTER ORGANIZED CELLS. IF A MARGINAL SEVERE THREAT DEVELOPS IN KS...THE THREAT WOULD LIKELY BE CONFINED TO THE LATE AFTERNOON WHEN INSTABILITY WILL BE MAXIMIZED ACROSS THE REGION. FURTHER SOUTH...THUNDERSTORMS MAY ALSO DEVELOP ACROSS OK...EAST TX AND IN THE TX COASTAL PLAINS DUE TO LIFT ASSOCIATED WITH A 50 TO 60 KT LOW-LEVEL JET. THE STRONG LOW-LEVEL FLOW AND VEERING LOW-LEVEL WINDS WITH HEIGHT MAY BE FAVORABLE FOR A FEW ROTATING THUNDERSTORMS CAPABLE OF STRONG WIND GUSTS MAINLY NEAR PEAK HEATING LATE THIS AFTERNOON. ..BROYLES/GRAMS.. 10/25/2006  From swody1 at goshenarc.org Wed Oct 25 11:59:41 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Wed, 25 Oct 2006 07:59:41 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 251200 SWODY1 SPC AC 251158 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0658 AM CDT WED OCT 25 2006 VALID 251300Z - 261200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... MID/UPPER LVL SHORT WAVE TROUGH IS MOVING EWD OVER THE 4-CORNERS THIS MORNING JUST AHEAD OF MORE LATITUDINAL TROUGH MOVING SEWD OVER THE NRN PLATEAU. MOISTURE PLUME FROM TROPICAL STORM PAUL IS EVIDENT THROUGH WATER VAPOR IMAGERY STRETCHING FROM THE LOCATION OF TROPICAL STORM PAUL OVER THE SRN TIP OF THE BAJA PENINSULA NEWD INTO THE SRN PLAINS. MID/UPPER LEVEL TROUGH MOVING SEWD THRU THE NRN PLATEAU IS EXPECTED TO INTENSIFY TODAY AS IT MOVES INTO THE 4-CORNERS AREA EJECTING WEAKER TROUGH JUST AHEAD OF IT INTO THE CENTRAL PLAINS. CONSIDERABLE CLOUD COVER OVER THE PLAINS SHOULD CONTINUE MUCH OF THE DAY LIMITING POTENTIAL INSTABILITY AND SEVERE STORM POTENTIAL. ...PARTS OF SRN KS/NRN OK INTO ERN TX... AS MID/UPPER LEVEL LOW DIGS INTO THE SWRN PORTIONS OF THE SWRN U.S. THIS AFTERNOON AND TONIGHT...STRONG UPPER LEVEL JET BETWEEN 130-160 KT WILL EXTEND FROM SRN AZ ENEWD INTO THE LOWER OH VALLEY. THIS WILL BE ACCOMPANIED BY 500 MB WINDS OF 80-90 KT TURNING AROUND THE BASE OF THE TROUGH FROM ERN NV INTO W TX. THE EXIT REGION OF THIS JET WILL BE COUPLING WITH WRN AREAS OF THE LOW LEVEL JET BY THE END OF THE PERIOD AS LOW LEVEL WINDS OF 40-50 KT EXTEND FROM THE CENTRAL PARTS OF THE TX GULF COAST INTO S CENTRAL MO. THIS IS WHEN THUNDERSTORM ACTIVITY IS EXPECTED TO INCREASE ACROSS THE PLAINS AS VERTICAL SHEAR INCREASES TONIGHT. AGAIN CONSIDERABLE CLOUDINESS IS EXPECTED TO INHIBIT POTENTIAL INSTABILITY AND SEVERE WEATHER POTENTIAL DURING THE PERIOD. ..MCCARTHY/GRAMS.. 10/25/2006  From swody1 at goshenarc.org Thu Oct 26 05:59:38 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 01:59:38 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 260603 SWODY1 SPC AC 260601 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0101 AM CDT THU OCT 26 2006 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF ERN TX/OK INTO THE LOWER MS VALLEY... ...SYNOPSIS... LEAD IMPULSE NOW OVER THE MID MS VALLEY WILL CONTINUE TO DEAMPLIFY AS IT MOVES THROUGH SHORTWAVE RIDGE AND INTO CONFLUENT FLOW REGIME OVER THE OH VALLEY AREA. IN ITS WAKE...A MUCH STRONGER SHORTWAVE TROUGH WILL MOVE ESEWD INTO THE SRN PLAINS THURSDAY AFTERNOON AND EVENING...THEN INTO THE LOWER MS VALLEY THURSDAY NIGHT. LEE CYCLOGENESIS WILL ACCOMPANY THIS FEATURE. THE DRYLINE WILL SHARPEN FROM WRN OK THROUGH WRN TX EARLY THURSDAY AS THE LOW DEVELOPS OVER WRN OK. THIS BOUNDARY WILL SHIFT EWD DURING THE DAY AS THE PACIFIC FRONT MERGES WITH IT. A WARM FRONT WILL DEVELOP AND EXTEND EWD FROM THE LOW ACROSS NRN OK. AS THE LOW SHIFTS EWD INTO THE LOWER MS VALLEY DURING THE EVENING...THE SLY LOW LEVEL JET WILL STRENGTHEN ACROSS PARTS OF LA AND MS. THIS WILL CONTRIBUTE TO A MARINE BOUNDARY LIFTING INLAND ALONG THE LA AND MS COASTS THURSDAY EVENING. ...SRN PLAINS THROUGH LOWER MS VALLEY AREA... PARTIALLY MODIFIED GULF AIR WITH BOUNDARY LAYER DEWPOINTS IN THE LOW TO MID 60S HAS ALREADY ADVECTED AS FAR N AS CNTRL OK WITH UPPER 60S ACROSS N CNTRL TX. PLUME OF DEEPER MOISTURE IS EXPECTED TO PERSIST ACROSS TX INTO PARTS OF THE LOWER MS VALLEY ALONG WARM CONVEYOR BELT WITH MOISTURE AUGMENTED BY REMNANTS OF PAUL. A RELATIVELY NARROW AXIS OF INSTABILITY MAY DEVELOP THURSDAY AFTERNOON W OF DEEPER MOIST PLUME FROM THE ERN HALF OF OK SWD THROUGH CNTRL AND ERN TX. HERE...MODEST 6.5 C/KM MID LEVEL LAPSE RATES WILL OVERSPREAD THE LOW LEVEL MOIST AXIS AND POTENTIAL FOR SURFACE HEATING WILL EXIST AS LOW CLOUDS MIX OUT IN DRY SLOT REGION. MLCAPE FROM 1000 TO 1500 J/KG WILL BE POSSIBLE. PRIMARY LOW LEVEL JET WILL SHIFT EWD THROUGH THE LOWER MS VALLEY AND SERN U.S. IN ASSOCIATION WITH DEAMPLIFYING LEAD IMPULSE. HOWEVER...SOME INCREASE AND BACKING OF THE LOW LEVEL FLOW SHOULD OCCUR FROM ERN OK INTO NERN TX AS THE LOW CONSOLIDATES OVER OK. THIS ALONG WITH APPROACHING 90+ KT MID LEVEL JET WILL RESULT IN FAVORABLE SHEAR PROFILES FOR SUPERCELLS. STRONGEST 0-1 KM SHEAR FOR LOW LEVEL MESOCYCLONES AND POSSIBLE TORNADOES DURING THE AFTERNOON IS EXPECTED JUST E OF SURFACE LOW AND NEAR WARM FRONT OVER NRN AND ERN OK OR SRN KS. STORMS ARE EXPECTED TO REDEVELOP OVER NRN OK/SRN KS DURING THE AFTERNOON AS WELL AS ALONG AND E OF DRYLINE/PACIFIC FRONT AS FORCING FOR ASCENT ATTENDING THE SHORTWAVE TROUGH INCREASES. VERTICAL SHEAR PROFILES WILL BE SUFFICIENT FOR SUPERCELLS WITH LARGE HAIL AND ISOLATED TORNADOES POSSIBLE. OTHER STORMS MAY DEVELOP FARTHER S ACROSS TX ALONG AND E OF PACIFIC FRONT. LOW LEVEL SHEAR PROFILES IN THIS REGION WILL NOT BE A STRONG AS FARTHER N...BUT DEEP LAYER SHEAR WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS. SOME STORMS MAY EVENTUALLY EVOLVE INTO LINE SEGMENTS WITH EMBEDDED SUPERCELLS AS THEY CONTINUE EWD INTO ERN TX DURING THE EVENING WITH A CONTINUING THREAT OF MAINLY DAMAGING WIND. SOME WEAKENING IS EXPECTED AS ACTIVITY MOVES TOWARD THE LESS UNSTABLE REGIME OVER AR OVERNIGHT. OTHER ACTIVITY WILL CONTINUE WITHIN THE PLUME OF DEEPER MOISTURE FROM SERN TX INTO THE LOWER MS VALLEY. LAPSE RATES WILL REMAIN WEAK IN THIS REGION. HOWEVER...RICHER LOW LEVEL MOISTURE ACCOMPANYING THE MARINE FRONT WILL ADVECT NWD INTO SRN LA/MS DURING THE EVENING. POTENTIAL WILL EXIST FOR SUPERCELLS AND ISOLATED TORNADOES...MAINLY OVERNIGHT FROM PARTS SERN TX INTO LA AND SRN MS AS THE LOW LEVEL JET STRENGTHENS...RESULTING IN FAVORABLE LOW LEVEL HODOGRAPHS. ..DIAL.. 10/26/2006  From swody1 at goshenarc.org Thu Oct 26 12:09:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 08:09:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261210 SWODY1 SPC AC 261209 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0709 AM CDT THU OCT 26 2006 VALID 261300Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE S CENTRAL U.S. INTO AR/LA.... ...SYNOPSIS... STRONG MID/UPPER LEVEL LOW CURRENTLY OVER THE SRN UT/CO BORDER WILL MOVE EWD OVER THE NWRN TX PANHANDLE BY LATER THIS AFTERNOON INTO NERN OK BY THE END OF THE PERIOD. SURFACE LOW CONTINUES TO DEEPEN OVER SERN CO AT THIS TIME AND WILL BE OVER NWRN OK BY 21Z INTO SWRN MO/NWRN AR BY FRI MORNING. A DRYLINE EXTENDS FROM JUST SW OF ICT THIS MORNING SWWD JUST W OF MAF WITH A WARM FRONTAL BOUNDARY FROM S CENTRAL KS SEWD THROUGH SERN OK INTO SERN LA. ALSO...A COLD FRONT EXTENDS FROM THE SERN CO LOW SWD AND SWWD THROUGH SERN AND S CENTRAL NM AND W CENTRAL AZ. THIS FRONTAL SYSTEM WILL MOVE EWD AS WELL THROUGH TONIGHT ENHANCING UPWARD ASCENT AND THUNDERSTORMS ACROSS PARTS OF KS...CENTRAL AND ERN OK AND TX INTO PARTS OF MO AND AR AND THE LOWER MS VALLEY DURING THE PERIOD. ...SERN KS/NERN OK INTO SWRN MO/NWRN AR... VERY STRONG RIBBON OF UPPER LEVEL WINDS OF 130-150 KT WILL EXTEND FROM CENTRAL AZ INTO CENTRAL OK AND NRN TX THROUGH THIS EVENING...THEN INTO SRN MO/NRN AR BY FRIDAY MORNING. CLOSE ANALYSIS OF THESE WINDS SHOW THAT THE NRN BRANCH OF THIS JET WILL BE FROM SERN AZ INTO SERN KS BY THIS AFTERNOON...WHILE THE SRN BRANCH EXTENDS FROM THE BAJA SPUR INTO CENTRAL TX. THUS...THERE WILL BE SOME UPPER LEVEL DIVERGENCE FROM CENTRAL OK SWD INTO CENTRAL TX TO ENHANCE UPWARD ASCENT ASSOCIATED WITH COLD FRONT/DRYLINE COMBINATION DURING THE AFTERNOON INTO TONIGHT. WINDS AT 500 MB REFLECT THIS STRUCTURE AS WELL WITH A 100 KT JET STREAK FROM SERN NM NEWD INTO S CENTRAL KS FOR THE NRN BRANCH AS THE SRN BRANCH OF 60-80 KT EXTENDS FROM THE TX BIG BEND INTO NERN TX. LOW LEVEL JET AXIS IS ANALYZED FARTHER E OUT AHEAD OF THE APPROACHING SYSTEM AS 40-50 KT WINDS ARE FORECAST FROM SWRN LA INTO WRN KY BY LATER THIS AFTERNOON. BUT...STRONG WLY FLOW AT LOW LEVELS INCREASE TONIGHT WHICH WILL AID IN LOW LEVEL FRONTAL FORCING ACROSS ERN KS INTO ERN TX. THIS TYPE OF KINEMATIC STRUCTURE LOOKS TO SET UP MORE OF A BIMODAL TYPE SITUATION OVER THE PLAINS LATER TODAY. MODELS INDICATE THAT MID LEVEL LAPSE RATES OVER SERN KS INTO THE NERN QUARTER OF OK WILL BE AROUND 7 C/KM WITH MLCAPE VALUES OF 1200-1600 J/KG THIS EVENING...AND DEEP LAYER SHEAR OF 50-70 KT. THUS...THIS AREA WILL BE ONE AREA TO CONSIDER FOR HAIL AND DAMAGING WINDS AS THE FRONTAL BOUNDARY/ASSOCIATED SQUALL LINE DEVELOPS ALONG/JUST AHEAD OF THE FRONT. ISOLATED TORNADOES WOULD ALSO NEED TO BE CONSIDERED ACROSS THIS AREA WITH THAT MUCH DEEP LAYER SHEAR AND WITH LCL/LFC LEVELS BEING AT/JUST BELOW 850 MB. ...SERN OK INTO NERN AND E CENTRAL TX... THIS WILL BE THE SECOND AREA IN THIS SITUATION AS THE SUBTLE SRN STREAM EXTENDS EWD ACROSS THIS REGION LATE THIS AFTERNOON AND EARLY TONIGHT. THERE COULD BE A FEW DISCRETE SUPERCELLS DEVELOP AHEAD OF THE COLD FRONT OVER PARTS OF SERN OK INTO NERN AND E CENTRAL TX WHERE FORECAST SOUNDINGS SHOW A BIT MORE INSTABILITY WITH MLCAPE NEAR 2000 J/KG AND CLOSER LCL/LFC LEVELS JUST BELOW 850 MB. THIS AREA WILL ALSO BE IN A MORE FAVORABLE EXIT REGION OF THE UPPER LEVEL JET STREAK TO ENHANCE ASCENT WITH DEEP LAYER SHEAR INCREASING TO AROUND 50 KT BY EARLY TONIGHT. AGAIN LARGE HAIL AND DAMAGING WINDS WILL BE THE MAIN THREATS...BUT A FEW TORNADOES COULD OCCUR LATER THIS AFTERNOON/EARLY TONIGHT WHERE THERE IS BETTER COUPLING OF LOW/MID LEVEL WINDS. MAIN THREAT OF DAMAGING WINDS WILL BECOME MORE LIKELY AFTER EARLY THIS EVENING AS MAIN VORTEX MOVES THROUGH OK AND THERE IS AN INCREASE IN WLY LOW LEVEL FLOW BEHIND THE MAIN FRONTAL PUSH THAT MOVES INTO SWRN MO INTO CENTRAL AR LATER TONIGHT. ..MCCARTHY/GRAMS.. 10/26/2006  From swody1 at goshenarc.org Thu Oct 26 19:53:34 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 15:53:34 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 261956 SWODY1 SPC AC 261955 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0255 PM CDT THU OCT 26 2006 VALID 262000Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM ERN OK/WRN AR SWD INTO E TX/LA/SWRN MS... ...SERN TX ACROSS SRN LA... STORMS ARE ONGOING ATTM ACROSS SERN TX AND INTO SWRN LA...WITHIN VERY MOIST BOUNDARY LAYER AIRMASS. LATEST VWPS AND 18Z LAKE CHARLES RAOB INDICATE SUFFICIENT SHEAR IN THE LOWEST 1 TO 2 KM FOR LOW-LEVEL MESOCYCLONE DEVELOPMENT -- THUS SUPPORTING A CONTINUED THREAT FOR A COUPLE OF TORNADOES. OTHERWISE...SEVERE THREAT APPEARS LIMITED INVOF THE TX/LA GULF COAST DUE TO VERY MOIST/MINIMALLY-UNSTABLE ENVIRONMENT. ADDITIONAL CONVECTIVE DEVELOPMENT IS EXPECTED ACROSS E TX THIS EVENING -- W AND NW OF ONGOING COASTAL STORMS -- AS FRONT APPROACHES FROM THE W AHEAD OF UPPER LOW/TROUGH. ALONG WITH POTENTIAL FOR AN ISOLATED TORNADO...LOCALLY-DAMAGING WINDS MAY ALSO OCCUR -- PARTICULARLY IF STORMS ORGANIZE LINEARLY ALONG/AHEAD OF FRONT. STORMS WILL CONTINUE/SHIFT EWD ACROSS THE SABINE RIVER OVERNIGHT...WITH AT LEAST A LOW-END SEVERE THREAT LINGERING THROUGH THE END OF THE PERIOD. ...NERN TX INTO WRN AR/NRN AND ERN OK... STRONG UPPER LOW NOW MOVING INTO THE WRN OK/NWRN TX PANHANDLES WILL CONTINUE EWD ACROSS OK THROUGH THE REMAINDER OF THE PERIOD. ASSOCIATED SURFACE LOW -- NOW S OF DODGE CITY KS -- WILL LIKEWISE SHIFT EWD...REACHING AR LATE IN THE PERIOD. BOUNDARY-LAYER AIRMASS ACROSS ERN OK/NERN TX CONTINUES TO MOISTEN AHEAD OF THE APPROACHING FEATURE...WHICH COMBINED WITH DAYTIME HEATING IS RESULTING IN MARGINAL DESTABILIZATION. THIS TREND SHOULD CONTINUE ACROSS ERN OK AND INTO WRN AR/NERN TX/NWRN LA INTO EARLY EVENING...AS COOLING ALOFT ASSOCIATED WITH THE UPPER LOW SPREADS EWD ACROSS MOISTENING BOUNDARY LAYER. ATTM...IT APPEARS THAT SCATTERED STORMS SHOULD BEGIN TO DEVELOP BY LATE THIS AFTERNOON/EARLY THIS EVENING INVOF A CONSOLIDATING WARM FRONT OVER N CENTRAL/NERN OK/SERN KS...WHILE SCATTERED TO ISOLATED STORMS ALSO DEVELOP SWD ALONG COLD FRONT ACROSS THE ERN HALF OF OK. DEEP-LAYER WIND FIELD WILL REMAIN FAVORABLE FOR SUPERCELLS...SO AT LEAST ISOLATED SEVERE STORMS ARE ANTICIPATED. ALONG WITH THE POTENTIAL FOR HAIL...LOCALLY-DAMAGING WINDS WILL BE POSSIBLE GIVEN STRENGTH OF WIND FIELD. GREATEST THREAT APPEARS TO EXIST OVER THE ARKLATEX...WHERE MOST FAVORABLE INSTABILITY/SHEAR COMBINATION IS EXPECTED TONIGHT. A BRIEF TORNADO OR TWO WILL ALSO BE POSSIBLE -- PARTICULARLY IN BACKED SURFACE FLOW NEAR/N OF WARM FRONT. STORMS/SEVERE THREAT WILL PERSIST/SHIFT EWD THROUGH THE PERIOD. ..GOSS.. 10/26/2006  From swody1 at goshenarc.org Fri Oct 27 00:56:56 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Thu, 26 Oct 2006 20:56:56 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270100 SWODY1 SPC AC 270058 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT THU OCT 26 2006 VALID 270100Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF SERN KS...ERN OK...ERN TX INTO THE LOWER MS VALLEY... ...SRN KS THROUGH ERN OK AND NERN TX... SURFACE ANALYSIS SHOWS A PACIFIC FRONT EXTENDING FROM A SURFACE LOW IN N CNTRL OK SSWWD THROUGH N CNTRL AND SWRN TX ALONG WITH AN E-W BOUNDARY ACROSS EXTREME NRN OK. A PRE-FRONTAL TROUGH EXTENDS FROM N CNTRL TX NWD INTO SERN OK. A WARM FRONT SEPARATING RICHER LOW LEVEL GULF MOISTURE FROM MODIFIED CP AIR EXTENDS FROM LA NWWD INTO NERN TX. THE SURFACE LOW WILL MOVE EWD THROUGH NRN OK OVERNIGHT WITHIN ZONE OF ASCENT ASSOCIATED WITH EWD ADVANCING SHORTWAVE TROUGH AND ITS ATTENDANT UPPER JET. TORNADIC STORMS THAT DEVELOPED EARLIER THIS EVENING ACROSS SWRN KS ALONG THE E-W BOUNDARY HAVE WEAKENED. OTHER STORMS ARE DEVELOPING FARTHER E ALONG/N OF THIS BOUNDARY ACROSS SERN KS. SOME POTENTIAL FOR AN ISOLATED TORNADO MAY EXIST NEXT COUPLE HOURS AS STORMS DEVELOP ON THIS BOUNDARY. HOWEVER...SWLY ORIENTATION OF THE STEERING FLOW RELATIVE TO THE SLIGHT SWD MOTION OF THE BOUNDARY HAS RESULTED IN STORMS BEING UNDERCUT AND BECOMING ELEVATED AS THEY CROSS ONTO THE COOL SIDE. THUS PRIMARY THREAT APPEARS TO BE TRANSITIONING TO HAIL...BUT EVEN THE HAIL THREAT IS SOMEWHAT LIMITED BY MODEST INSTABILITY. SOME POTENTIAL STILL EXISTS FOR OTHER STORMS TO DEVELOP ACROSS ERN OK. THE NEAR SURFACE FLOW IS STILL BACKED TO SELY IN THIS REGION E OF THE SURFACE LOW. WITH PRIMARY LOW LEVEL JET EXPECTED TO REMAIN SE OF THIS AREA...LOW LEVEL HODOGRAPHS WILL NOT BE PARTICULARLY LARGE. HOWEVER...SUFFICIENT VEERING...LOW LEVEL AND DEEP LAYER SHEAR EXIST FOR A THREAT OF SUPERCELLS WITH HAIL AND LOW LEVEL MESOCYCLONES...BUT CONDITIONAL UPON THE INITIATION OF SURFACE BASED STORMS. THE INSTABILITY AXIS IN THIS REGION IS NARROW...AND AS THE BOUNDARY LAYER CONTINUES TO COOL IT APPEARS MANY OF THE STORMS MAY BE INITIATED WITHIN WEAK WARM ADVECTION REGIME ABOVE THE COOLER BOUNDARY LAYER ACROSS EXTREME ERN OK INTO AR. FARTHER S ACROSS NERN TX...OTHER STORMS ARE DEVELOPING WITHIN ZONE OF ASCENT ALONG AND JUST E OF PRE-FRONTAL TROUGH WHERE THE ATMOSPHERE REMAINS MODERATELY UNSTABLE WITH MLCAPE FROM 1000 TO 1500 J/KG. LOW LEVEL SHEAR IS WEAKER IN THIS REGION THAN FARTHER NORTH. HOWEVER...EFFECTIVE SHEAR IN EXCESS OF 50 KT IS MORE THAN SUFFICIENT FOR SUPERCELLS. SOME STORMS MAY ALSO EVOLVE INTO BOWING SEGMENTS. PRIMARY THREAT APPEARS TO BE DAMAGING WIND...THOUGH SOME HAIL IS POSSIBLE WITH THE STRONGER STORMS. OVERALL HAIL THREAT IS SOMEWHAT LIMITED BY WEAK MID LEVEL LAPSE RATES. ...SERN TX THROUGH LA AND SRN MS... STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN PLUME OF DEEP MOISTURE FROM SERN TX INTO LA AND SRN MS OVERNIGHT. SWLY LOW LEVEL JET IS FORECAST TO STRENGTHEN TO IN EXCESS OF 50 KT FROM SERN TX INTO THE LOWER MS VALLEY. THIS WILL HELP TO ADVECT BOUNDARY LAYER DEWPOINTS NEAR 70 FARTHER INLAND ACROSS LA IN WAKE OF RETREATING WARM FRONT. THE INCREASING LOW LEVEL JET WILL RESULT IN FAVORABLE 0-1 KM HODOGRAPHS FOR A THREAT OF ISOLATED TORNADOES GIVEN INLAND ADVECTION OF RICHER LOW LEVEL MOISTURE AS STORMS TRAIN FROM SW-NE ALONG WARM CONVEYOR BELT. PRIMARY LIMITING FACTOR ARE THE WEAK LAPSE RATES AND MARGINAL INSTABILITY. ..DIAL.. 10/27/2006  From swody1 at goshenarc.org Fri Oct 27 05:18:40 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 27 Oct 2006 01:18:40 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 270521 SWODY1 SPC AC 270520 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1220 AM CDT FRI OCT 27 2006 VALID 271200Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE CNTRL AND ERN GULF COASTAL AREA INTO PARTS OF NWRN FL... ...SYNOPSIS... POSITIVELY TILTED SHORTWAVE TROUGH PRESENTLY OVER OK WILL MOVE ESEWD THROUGH THE LOWER MS VALLEY AND SERN STATES FRIDAY...REACHING THE CAROLINAS LATE FRIDAY NIGHT. SURFACE LOW AND COLD FRONT WILL ATTEND THIS FEATURE. THE LOW SHOULD BE OVER THE WRN TN VALLEY WITH A COLD FRONT EXTENDING SWD THROUGH THE LOWER MS VALLEY AT THE START OF THIS PERIOD. THE LOW WILL SHIFT ENEWD INTO ERN KY WITH TRAILING FRONT THROUGH ERN TN...WRN GA AND INTO THE ERN GULF EARLY FRIDAY EVENING. BY THE END OF THIS PERIOD...THIS BOUNDARY SHOULD EXTEND FROM EXTREME ERN VA/NC SWWD THROUGH NRN FL. ...CNTRL AND ERN GULF COASTAL AREA THROUGH NWRN FL... HEIGHT FALLS ACCOMPANYING THE UPPER TROUGH WILL CONTRIBUTE TO A STRONG SWLY 60+ KT LOW LEVEL JET THAT WILL SHIFT EWD THROUGH THE SERN STATES DURING THE DAY AS SURFACE LOW ADVANCES THROUGH THE TN VALLEY. THIS SHOULD RESULT IN ADVECTION OF NEAR 70 DEWPOINTS INTO SRN PORTIONS OF GULF COASTAL STATES. HOWEVER...NWD RECOVERY OF AIRMASS WILL BE LIMITED BY WIDESPREAD RAIN EXPECTED WITHIN PLUME OF DEEPER MOISTURE ALONG WARM CONVEYOR BELT OVER THE SERN STATES. NEAR THE COAST WHERE RICHER MOISTURE ADVECTS INLAND...MLCAPE FROM 500 TO 1000 J/KG WILL BE POSSIBLE WITHIN THE MOIST...WEAK LAPSE RATE ENVIRONMENT. STORMS WILL LIKELY CONTINUE DEVELOPING IN ZONE OF ASCENT WITHIN THE PRE-FRONTAL WARM SECTOR AND SHIFT EWD THROUGH THE SERN STATES DURING THE DAY. STRONGER STORMS ARE EXPECTED JUST INLAND OF THE COAST FROM SERN LA THROUGH SRN AL...SWRN GA AND THE FL PANHANDLE WHERE INFLOW FROM HIGHER THETA-E AIR WILL EXIST. THE INTENSIFYING LOW LEVEL JET WILL RESULT IN LARGE LOW LEVEL HODOGRAPHS. THIS ALONG WITH STRONG SHEAR THROUGH A DEEPER LAYER WILL BE SUPPORTIVE OF ORGANIZED STORM STRUCTURES INCLUDING BOW ECHOES AND SUPERCELLS CAPABLE OF PRODUCING DAMAGING WIND AND ISOLATED TORNADOES. OVERALL THREAT MAY BE TEMPERED SOMEWHAT BY THE MARGINAL THERMODYNAMIC ENVIRONMENT. ...COASTAL CAROLINAS... NEAR SURFACE TRAJECTORIES WILL EMANATE FROM CP HIGH PRESSURE OFF THE ATLANTIC SEABOARD IN THIS REGION UNTIL FRIDAY AFTERNOON AND EVENING WHEN THE FLOW SHOULD VEER TO SLY IN ADVANCE OF SURFACE LOW. THIS WILL ALLOW MODIFYING BOUNDARY LAYER AIR WITH DEWPOINTS IN THE 60S TO ADVECT NWD TOWARD THE COASTAL CAROLINAS OVERNIGHT. THE RICHER MOISTURE WILL LIKELY RESIDE S OF A COASTAL BOUNDARY THAT COULD MOVE INLAND LATER FRIDAY NIGHT. LOW LEVEL AND MID LEVEL WIND FIELDS WILL STRENGTHEN SIGNIFICANTLY AS THE UPPER TROUGH AND ATTENDANT LOW LEVEL JET MOVE TOWARD THE CAROLINAS. WITH RAIN EXPECTED TO SPREAD EWD INTO THE COOL AIRMASS ALREADY IN PLACE OVER THE CAROLINAS BY EARLY FRIDAY...INLAND RECOVERY WILL BE DIFFICULT EXCEPT POSSIBLY NEAR THE COASTAL AREAS. THE THREAT FOR ISOLATED TORNADOES OR DAMAGING WIND MAY INCREASE IN VICINITY OF THE COASTAL BOUNDARY FRIDAY NIGHT AS SHEAR PROFILES INCREASE AND HIGHER THETA-E AIR ADVECTS INLAND. HOWEVER...GIVEN THE POTENTIAL LIMITING FACTORS UPON THE THERMODYNAMIC ENVIRONMENT...LOW SEVERE PROBABILITIES WILL BE MAINTAINED AT THIS TIME. AN UPGRADE TO SLIGHT RISK MIGHT BE NECESSARY IN LATER OUTLOOKS IF IT BEGINS TO APPEAR MORE INSTABILITY WILL DEVELOP THAN CURRENTLY ANTICIPATED. ..DIAL/GRAMS.. 10/27/2006  From swody1 at goshenarc.org Fri Oct 27 12:25:12 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Fri, 27 Oct 2006 08:25:12 -0400 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 271228 SWODY1 SPC AC 271226 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0726 AM CDT FRI OCT 27 2006 VALID 271300Z - 281200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE CENTRAL GULF COAST STATES INTO FL... POWERFUL UPPER LOW CURRENTLY OVER OK WILL TRACK EASTWARD INTO WESTERN TN BY 00Z...THEN ACCELERATE RAPIDLY NORTHEASTWARD INTO THE CENTRAL APPALACHIANS BY 28/12Z. RELATIVELY DEEP SURFACE LOW WILL TRACK ALONG SIMILAR PATH THROUGH THE PERIOD AS TRAILING COLD FRONT SWEEPS ACROSS THE SOUTHEAST STATES. THIS FRONT WILL BE THE PRIMARY FOCUS FOR STRONG/SEVERE THUNDERSTORMS TODAY. ...LA/MS/AL THIS MORNING... INTENSE THUNDERSTORMS ARE ONGOING THIS MORNING OVER SOUTHEAST LA/SOUTHERN MS. THESE STORMS ARE IN PRE-FRONTAL WARM SECTOR CHARACTERIZED BY DEWPOINTS IN THE UPPER 60S/LOWER 70S AND MUCAPE OF 500-1000 J/KG. LOCAL VAD DATA IN THIS REGION SHOWS VERY STRONG LOW LEVEL AND DEEP LAYER VERTICAL SHEAR /3KM SR-HELICITY OF 300-500 M2/S2 AND 6KM SHEAR OF 50-65 KNOTS/. STRENGTH OF SHEAR AND INCREASING FORCING FOR ASCENT WILL PROMOTE CONTINUED SUPERCELL POTENTIAL THROUGH THE MORNING AND EARLY AFTERNOON. WEAK LAPSE RATES AND MINIMAL CAPE WILL LESSEN THE HAIL THREAT. HOWEVER...DAMAGING WINDS AND TORNADOES WILL BE POSSIBLE IN STRONGER CELLS. ...GA/FL THIS AFTERNOON AND TONIGHT... VERY STRONG SOUTHERLY LOW LEVEL JET WILL BE MAINTAINED THROUGH THE AFTERNOON AND EVENING AS LINE OF STORMS PROGRESSES EASTWARD INTO PARTS OF GA/FL. EXTENT OF DAYTIME HEATING IS UNCERTAIN OVER THIS REGION...LIMITING CONFIDENCE IN MORE ORGANIZED SEVERE THREAT. NEVERTHELESS...WITH 60-70 KNOT LOW LEVEL WINDS AND APPROACHING SQUALL LINE...POTENTIAL WILL EXIST FOR DAMAGING WINDS AND ISOLATED TORNADOES IN STRONGEST OF CELLS. ...CAROLINAS OVERNIGHT... FINALLY...MODELS AGREE ON LOW LEVEL MOISTENING/DESTABILIZATION ACROSS THE CAROLINAS OVERNIGHT TONIGHT AS UPPER SYSTEM APPROACHES AND LOW LEVEL WINDS STRENGTHEN. DESPITE VERY STRONG WIND FIELDS...WILL MAINTAIN ONLY LOW SEVERE PROBABILITIES AT THIS TIME DUE TO FORECAST OF WEAK LAPSE RATES AND LACK OF CONFIDENCE IN RICH ATLANTIC MOISTURE PLUME. HOWEVER...THIS AREA WILL BE MONITORED IN LATER UPDATES FOR THE POTENTIAL OF GREATER DESTABILIZATION AND POSSIBLE OUTLOOK UPGRADE TO SLIGHT RISK. ..HART/GRAMS.. 10/27/2006  From swody1 at goshenarc.org Sun Oct 29 15:51:21 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 10:51:21 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291554 SWODY1 SPC AC 291552 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0952 AM CST SUN OCT 29 2006 VALID 291630Z - 301200Z ...NO SVR TSTM AREAS FORECAST... ...NORTHEAST... A DEEP UPPER LOW OVER QUEBEC WILL SLOWLY MOVE NEWD TODAY. LIFT AHEAD OF THE UPPER TROUGH AXIS ALONG WITH STEEP LAPSE RATES WILL SUPPORT ISOLATED TSTMS OVER PORTIONS OF ERN/NRN ME THROUGH MID AFTERNOON. ADDITIONALLY...UNIDIRECTIONAL WLY FLOW ALONG WITH STEEP LOW LEVEL LAPSE RATES ABOVE WARM WATERS OF LAKE ONTARIO WILL CONTINUE TO SUPPORT A LAKE EFFECT RAIN/SNOW BAND EXTENDING INTO NWRN UPSTATE NY. SUFFICIENT INSTABILITY GIVEN THE WARM LAKE TEMPERATURES AND COLD MID LEVEL TEMPERATURES WILL SUPPORT ISOLATED TSTMS IN THIS AREA AS WELL. ...WRN MT... A STRONG UPPER TROUGH WILL MOVE SEWD FROM SRN BRITISH COLUMBIA THIS MORNING THROUGH THE NRN ROCKIES TONIGHT. AHEAD OF THIS TROUGH...A COLD FRONT WILL PUSH SWD ACROSS MT. MODERATE UPSLOPE FLOW ALONG THE NRN ROCKIES FRONT RANGE IN THE WAKE OF A COLD FRONT ALONG WITH MID LEVEL FRONTOGENETIC FORCING AND STEEP MID LEVEL LAPSE RATES MAY SUPPORT A FEW LIGHTNING STRIKES LATE THIS AFTERNOON AND OVERNIGHT. ...SRN AZ/SWRN NM... A BROAD FETCH OF MID/HIGH LEVEL PACIFIC MOISTURE WILL STREAM ACROSS THE REGION THROUGH TONIGHT AHEAD OF AN UPPER TROUGH LOCATED OFF THE SRN CA/BAJA CA COAST THIS MORNING. 12Z OBSERVED SOUNDINGS AT TUCSON AND GUAYMAS /SONORA MX/ BOTH INDICATED STEEP LAPSE RATES IN THE RELATIVELY MOIST 500-400 MB LAYER. SUFFICIENT LIFT AHEAD OF THE UPPER TROUGH MAY SUPPORT AN ISOLATED LIGHTNING STRIKE IF MOISTENING CAN OCCUR JUST BELOW THIS LAYER. COVERAGE OF THUNDERSTORMS WILL BE INSUFFICIENT TO WARRANT A CONTOURED AREA. ..CROSBIE/EVANS.. 10/29/2006  From swody1 at goshenarc.org Sun Oct 29 19:11:53 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 14:11:53 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 291912 SWODY1 SPC AC 291910 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0110 PM CST SUN OCT 29 2006 VALID 292000Z - 301200Z ...NO TSTM AREAS FORECAST... ...SYNOPSIS... UPPER LOW/TROUGH WILL CONTINUE RETREATING NEWD AWAY FROM THE NERN CONUS...WHILE A SECOND TROUGH -- CONSISTING OF A PHASED NRN AND SRN STREAM SYSTEM -- MOVES INTO THE ROCKIES THROUGH THE END OF THE PERIOD. A FEW CG LIGHTNING STRIKES HAVE OCCURRED DOWNSTREAM OF LK ONTARIO OVER THE PAST COUPLE OF HOURS...BUT EXPECT LIGHTNING POTENTIAL TO DIMINISH WITH TIME. THOUGH AN ADDITIONAL STRIKE OR TWO MAY OCCUR IN THIS AREA -- OR ACROSS PARTS OF WRN MT AND VICINITY AS NRN STREAM VORT MAX MOVES ACROSS THIS REGION DURING THE SECOND HALF OF THE PERIOD...IT APPEARS ATTM THAT NEITHER AREA REQUIRES 10% COVERAGE/PROBABILITY AREA. ..GOSS.. 10/29/2006  From swody1 at goshenarc.org Mon Oct 30 00:46:13 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Sun, 29 Oct 2006 19:46:13 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300048 SWODY1 SPC AC 300047 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0647 PM CST SUN OCT 29 2006 VALID 300100Z - 301200Z ...NO TSTM AREAS FORECAST... IN WAKE OF THE STRONG UPPER CYCLONE EXITING NEW ENGLAND THIS EVENING...A FLOW OF CONTINENTAL POLAR AIR WILL DOMINATE THE ERN TWO-THIRDS OF THE COUNTRY. THIS WILL LIMIT TSTM PROSPECTS. IN THE WEST...A COLD UPPER TROUGH WAS DIGGING SEWD INTO THE NRN INTERMOUNTAIN REGION. ISOLD TSTMS HAVE BEEN OCCURRING ACROSS NRN ID AND ERN WA LATE THIS AFTN AS LAPSE RATES STEEPEN COINCIDENT WITH STRONG ASCENT. CONVECTION WILL LARGELY BE DIURNAL AND TSTM PROBABILITIES WILL DECREASE QUICKLY THIS EVE. ..RACY.. 10/30/2006  From swody1 at goshenarc.org Mon Oct 30 05:36:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 30 Oct 2006 00:36:29 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 300539 SWODY1 SPC AC 300537 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1137 PM CST SUN OCT 29 2006 VALID 301200Z - 311200Z ...NO SVR TSTM AREAS FORECAST... ...LWR OH VLY/OZARKS AND ERN PARTS OF THE SRN PLAINS... A SHORTWAVE TROUGH EMBEDDED WITHIN THE SRN BRANCH OF THE WLYS WILL MOVE FROM THE SRN GREAT BASIN EARLY MON TO THE SRN PLAINS BY EARLY TUE. A STRONGER NRN STREAM IMPULSE MOVING ACROSS THE INTERMOUNTAIN WEST EARLY IN THE DAY WILL AMPLIFY AS IT REACHES NRN MN BY 12Z TUE. THE ASSOCD COLD FRONT WILL SURGE SEWD IN WAKE OF THIS SYSTEM... REACHING A MI...SRN IL...SRN OK...NRN TX LINE BY EARLY TUE. HEIGHT FALLS SPREADING ACROSS THE ROCKIES WERE ALREADY RESULTING IN A MODEST RETURN FLOW REGIME ACROSS THE WRN GULF BASIN. THIS MOISTENING WILL CONTINUE FROM THE TX COASTAL PLAIN NWD INTO THE OZARKS THROUGH MONDAY BELOW AN H85 CAP. THE LOW-LEVEL FLOW IS EXPECTED TO TURN MORE ZONAL MON EVE...SHUNTING THE PRIMARY MOIST AXIS NEWD TOWARD THE LWR OH VLY. AS STRONGER LARGE SCALE ASCENT SPREADS EWD MON EVE COINCIDENT WITH THE SURGING COLD FRONT...THE COLUMN SHOULD SATURATE. THIS WILL CONTRIBUTE TO DESTABILIZATION AND SUBSEQUENT INCREASE IN ELEVATED CONVECTION ALONG NWRN EDGE OF THE MOISTURE PLUME. INITIAL TSTM DEVELOPMENT OVER CNTRL MO WILL SPREAD EWD INTO THE LWR OH VLY MON NIGHT...WITH TRAILING DEVELOPMENT PSBL INTO THE OZARKS AND ERN OK BY 12Z TUE TO THE N OF THE COLD FRONT. DESPITE FAVORABLE VERTICAL SHEAR... THERMODYNAMIC PROFILES SHOULD REMAIN UNFAVORABLE FOR SEVERE TSTMS. ..RACY.. 10/30/2006  From swody1 at goshenarc.org Mon Oct 30 17:55:29 2006 From: swody1 at goshenarc.org (Severe Weather Outlook Day 1) Date: Mon, 30 Oct 2006 12:55:29 -0500 Subject: [SWODY1] SWODY1 Message-ID: ACUS01 KWNS 301758 SWODY1 SPC AC 301756 DAY 1 CONVECTIVE OUTLOOK RESENT 1 NWS STORM PREDICTION CENTER NORMAN OK 1156 AM CST MON OCT 30 2006 VALID 301630Z - 311200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... A PROGRESSIVE SHORTWAVE TROUGH WILL MOVE FROM THE SWRN STATES INTO THE SRN PLAINS THROUGH TONIGHT. STEEP MID LEVEL LAPSE RATES ALONG WITH A PLUME OF MID LEVEL MOISTURE SHOULD SUPPORT ISOLATED TSTMS OVER PORTIONS OF THE SRN HIGH PLAINS AND FAR SRN ROCKIES THIS AFTERNOON. FURTHER AHEAD OF THIS SYSTEM...MODERATE SLY RETURN FLOW WILL SUPPORT CONTINUED LOW LEVEL MOISTURE TRANSPORT OVER ERN PORTIONS OF THE SRN PLAINS AND THE LOWER/MID MS VALLEY REGION. MEANWHILE...A NRN STREAM SHORTWAVE TROUGH OVER THE NRN ROCKIES WILL SHIFT EWD INTO THE NRN PLAINS. ASSOCIATED WITH THIS SYSTEM...A CANADIAN COLD FRONT WILL MOVE QUICKLY SWD THROUGH THE NRN/CENTRAL PLAINS THIS AFTERNOON...BEFORE EXTENDING FROM NRN TX INTO THE WRN GREAT LAKES BY TOMORROW MORNING. ...OZARK REGION... THE 12Z SHV SOUNDING INDICATED THE MOISTURE DEPTH WAS AROUND 1 KM...WITH A PRONOUNCED INVERSION ABOVE THIS LAYER. A THICK BAND OF MID/HIGH CLOUDS ASSOCIATED WITH THE APPROACHING SHORTWAVE TROUGH WILL TRANSITION ACROSS THE AREA THROUGH THE AFTERNOON. THE PRESENCE OF THIS CLOUD COVER IS ANTICIPATED TO INHIBIT FULL HEATING/MIXING POTENTIAL. STEADY SLY LOW LEVEL FLOW SHOULD ALLOW FOR DWPTS TO CONTINUE TO RISE INTO THE LOWER 60S BY LATE THIS EVENING. LOW LEVEL VERTICAL MOTION IS ANTICIPATED TO INCREASE OVERNIGHT AHEAD OF AN APPROACHING CANADIAN COLD FRONT AS A LOW LEVEL JET BECOMES BETTER DEFINED. AT THE SAME TIME...AN APPROACHING SHORTWAVE TROUGH AND ASSOCIATED COOLING MID LEVEL TEMPERATURES WILL SUPPORT STEEPENING LAPSE RATES. FCST SOUNDINGS INDICATE THAT JUST AHEAD OF THE COLD FRONT...SUFFICIENT LIFT/COOLING WILL DEVELOP TO ERODE THE LOW LEVEL INVERSION LAYER RESULTING IN SCT THUNDERSTORM DEVELOPMENT. ALTHOUGH MARGINAL INSTABILITY IS ANTICIPATED /MUCAPES FROM 750-1000 J/KG/ MODERATE MID LEVEL WIND FIELDS /50-60 KTS AT 500 MB/ WILL SUPPORT SUFFICIENT VERTICAL SHEAR FOR SOME STORM ROTATION. COMBINED WITH STEEP LAPSE RATES...ISOLATED MARGINALLY SVR HAIL WILL BE POSSIBLE. ..CROSBIE/EVANS.. 10/30/2006