MESOSCALE DISCUSSION NWS STORM PREDICTION CENTER

[CaptinCrunch]

MESOSCALE DISCUSSION 2500
NWS STORM PREDICTION CENTER NORMAN OK
0217 PM CST MON NOV 28 2005

AREAS AFFECTED...MIDDLE TN/CNTRL KY/EXTREME SE INDIANA INTO ERN
KY/ERN TN

CONCERNING...TORNADO WATCH 885...

VALID 282017Z - 282145Z



VALID PORTION OF TORNADO WATCH 885 CONTINUES UNTIL 00Z ALONG/AHEAD
OF CONVECTIVE LINE MOVING EWD ACROSS CNTRL KY/MIDDLE TN...WITH AN
ISOLD THREAT FOR DAMAGING WIND GUSTS AND A TORNADO OR TWO
CONTINUING. WILL MONITOR TRENDS FOR NECESSITY OF ADDITIONAL WATCH
ISSUANCE INTO ERN TN/ERN KY.

RUC DIAGNOSTICS/WSR-88D VADS CONTINUE TO DEPICT RATHER STRONG
AMBIENT WIND FIELD IN PLACE ALONG/AHEAD OF CONVECTIVE LINE ADVANCING
ACROSS CNTRL KY/MIDDLE TN...WITH 0-1 KM SRH VALUES OF 400-600 M2/S2.
HOWEVER GIVEN CURRENT RADAR CHARACTER OF CONVECTIVE LINE AND WEAK
INSTABILITY DOWNSTREAM /REF 18Z BNA RAOB/...SEVERE THREAT WOULD
LIKELY DECREASE/REMAIN MARGINAL WITH EWD TRANSITION TOWARD ERN
KY/ERN TN. ALTHOUGH NOT CURRENTLY ANTICIPATED...WILL CONTINUE TO
CONVECTIVE TRENDS OF THE NEXT FEW HOURS FOR POSSIBILITY OF
ADDITIONAL WATCH ISSUANCE INTO ERN KY/ERN TN.

[Brent]

MESOSCALE DISCUSSION 2501
NWS STORM PREDICTION CENTER NORMAN OK
0439 PM CST MON NOV 28 2005

AREAS AFFECTED...AL/WRN FL PANHANDLE

CONCERNING...TORNADO WATCH 884...

VALID 282239Z - 282345Z

TORNADO THREAT APPEARS TO BE INCREASING IN THE SHORT TERM ACROSS
CNTRL/SCNTRL AL IN TORNADO WATCH 884...NAMELY IN A CORRIDOR FROM
BIRMINGHAM TO NEAR MONTGOMERY.

STRONG MESOCYCLONES HAVE BEEN COMMON OVER THE PAST HOUR OR TWO
ALONG/SOUTH OF THE BIRMINGHAM AREA. WITHIN WEDGE OF WARM/UNSTABLE
AIR...ADDITIONAL TSTMS WEST OF THE SELMA AL AREA WILL CONTINUE TO
INTENSIFY AND PROGRESS NEWD. THESE STORMS WILL INTERACT WITH/CROSS
EFFECTIVE WARM FRONTAL WEDGE ARCING NW-SW FROM CNTRL AL INTO THE FL
PANHANDLE OVER THE NEXT FEW HOURS. NEAR THIS BOUNDARY...LOW LEVEL
FLOW IS BACKED TO SELY...WITH 0-1 SRH VALUES OF 300 M2/S2 OR GREATER
BEING VERY FAVORABLE FOR STORM ROTATION/TORNADOES.

..GUYER.. 11/28/2005

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2502
   NWS STORM PREDICTION CENTER NORMAN OK
   0613 PM CST MON NOV 28 2005
   
   AREAS AFFECTED...FL PANHANDLE
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 290013Z - 290145Z
   
   PRIMARY SEVERE THREAT IS EXPECTED TO REMAIN OFFSHORE OF THE CNTRL FL
   PANHANDLE NEXT FEW HOURS WITH ONLY A LIMITED THREAT INLAND. A WW IS
   NOT ANTICIPATED UNLESS OFFSHORE BOUNDARY BEGINS TO RETREAT NWD.
   
   EARLY THIS EVENING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM THE N
   CNTRL FL PENINSULA NWWD THROUGH THE NERN GULF JUST OFFSHORE OF THE
   FL PANHANDLE THEN INLAND OVER THE WRN FL PANHANDLE. LATEST RUC
   OBJECTIVE ANALYSIS SUGGESTS THE ATMOSPHERE IS MODERATELY UNSTABLE S
   OF THE BOUNDARY...BUT ONLY MARGINAL ELEVATED INSTABILITY EXISTS ON
   THE COOL SIDE OF THE BOUNDARY ACROSS THE CNTRL FL PANHANDLE. STORMS
   ARE DEVELOPING WITHIN WHAT APPEARS TO BE A ZONE OF ISENTROPIC LIFT
   ASSOCIATED WITH SLY LOW LEVEL FLOW INTERSECTING THE BOUNDARY. CELLS
   WILL HAVE SOME POTENTIAL TO INTENSIFY AND PRODUCE A BRIEF TORNADO AS
   THEY CROSS THE BOUNDARY OVER THE NERN GULF WHERE THE LOW LEVEL SHEAR
   IS ENHANCED. HOWEVER...STORMS WILL LIKELY BECOME ELEVATED AND WEAKEN
   AS THEY MOVE INLAND. UNLESS THE OFFSHORE BOUNDARY BEGINS TO SHIFT
   NWD...THE INLAND SEVERE THREAT IS EXPECTED TO REMAIN LIMITED.
   
   ..DIAL.. 11/29/2005
   
   
   ATTN...WFO...TAE...
   
   29398332 29338435 30328546 30888524 30208339

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2503
   NWS STORM PREDICTION CENTER NORMAN OK
   0710 PM CST MON NOV 28 2005
   
   AREAS AFFECTED...ERN SD/SE ND AND WRN/NRN MN
   
   CONCERNING...BLIZZARD CONDITIONS
   
   VALID 290110Z - 290545Z
   
   BLIZZARD LIKE CONDITIONS WILL CONTINUE FROM ERN SD/SE ND INTO NW MN
   THIS EVENING. SNOW RATES OF 1 IN/HR OR GREATER WILL BE MOST
   PROLONGED THROUGH 06Z ACROSS SE ND INTO PORTIONS OF NW/NCNTRL
   MN...WHILE SNOW RATES SHOULD GRADUALLY DECREASE THROUGH MID EVENING
   ACROSS ERN SD.
   
   VERTICALLY STACKED CYCLONE OVER NRN IA/SRN MN CONTINUES TO OCCLUDE
   EARLY THIS EVENING...WITH 985 MB SFC LOW CENTERED OVER SE MN AT 01Z.
   ON THE NW PERIPHERY OF THIS CYCLONE...DEFORMATION AXIS OF HEAVY SNOW
   WILL REMAIN FOCUSED THIS EVENING BETWEEN MID LEVEL /600-800 MB/
   FRONTOGENETICAL COMPONENT AND TROWAL /TROUGH OF WARM AIR ALOFT/
   AIRSTREAM ARCING ACROSS NRN MN/FAR ERN DAKOTAS PER LATEST MODEL
   DIAGNOSTICS/CROSS SECTIONS.
   
   MAINTENENCE OF EXISTING RELATIVELY WELL-ORGANIZED BAND OF SNOW
   ACROSS NW/NCNTRL MN INTO ERN SD APPEARS LIKELY INTO THE
   OVERNIGHT...WITH SNOW RATES GRADUALLY DECREASING ON THE SRN EXTENT
   ACROSS ERN SD. SIMILAR TO 00Z ABERDEEN RAOB...RUC FCST SOUNDINGS FOR
   SE ND INTO NW/NCNTRL MN FEATURE DEEPLY SATURATED THERMODYNAMIC
   PROFILES THIS EVENING...WITH AMPLE UVVS COINCIDENT WITH FAVORABLE
   DENDRITIC GROWTH LAYER. SNOW RATES OF 1 IN/HR WILL REMAIN POSSIBLE
   WITH THE HEAVIER BANDS. IN ADDITION...VERY STRONG N/NW WINDS WILL
   CONTINUE TO CAUSE HAZARDOUS BLIZZARD LIKE CONDITIONS...WITH ERN
   DAKOTAS WSR-88D VAD DATA/00Z ABERDEEN RAOB SAMPLING 50-70 KT WINDS
   IN THE LOWEST FEW KM.
   
   ..GUYER.. 11/29/2005
   
   
   ...NOTICE...
   SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
   SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
   TIMES A DAY...BETWEEN 00-01 UTC...06-07 UTC...12-13 UTC...
   AND 18-19 UTC FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.
   
   ATTN...WFO...DLH...MPX...FGF...FSD...ABR...BIS...
   
   48859460 48109224 46819409 45499604 43689654 43529717
   43809812 44759887 46509808 48319615

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2504
   NWS STORM PREDICTION CENTER NORMAN OK
   0749 PM CST MON NOV 28 2005
   
   AREAS AFFECTED...SRN AND ERN AL THROUGH EXTREME WRN GA
   
   CONCERNING...TORNADO WATCH 886...
   
   VALID 290149Z - 290315Z
   
   THREAT FOR ISOLATED TORNADOES IS EXPECTED TO PERSIST NEXT 2-3 HOURS
   MAINLY FROM S CNTRL THROUGH E CNTRL AL. A MORE LIMITED THREAT MAY
   SPREAD INTO EXTREME WRN GA AFTER 02Z. CONVECTIVE TRENDS WILL
   CONTINUE TO BE MONITORED FOR A POSSIBLE WW IN WRN GA AS STORMS
   APPROACH THE ERN EDGE OF WW 886.
   
   A LINE OF SEVERE STORMS CONTAINING DISCRETE SUPERCELLS EXTENDS FROM
   JUST E OF CLEBURNE COUNTY IN ERN AL SWWD TO MONROE COUNTY IN SRN AL.
   THE LINE CONTINUES SLOWLY EWD WHILE THE INDIVIDUAL CELLS MOVE NEWD
   AT AROUND 35 KT. STORMS ARE DEVELOPING JUST AHEAD OF A COLD FRONT
   THAT EXTENDS FROM THE TN VALLEY SWWD THROUGH CNTRL AND SWRN AL. THE
   ATMOSPHERE E OF THIS BOUNDARY REMAINS MARGINALLY UNSTABLE IN A
   NARROW AXIS FROM SRN THROUGH E CNTRL AL...AND STORMS ARE CURRENTLY
   MOVING THROUGH THE AXIS OF MAXIMUM INSTABILITY. A SECONDARY BOUNDARY
   EXTENDS FROM THE FL PANHANDLE NWWD THROUGH S CNTRL AL WHERE IT
   INTERSECTS THE COLD FRONT. TRENDS HAVE BEEN FOR LOW LEVEL
   MESOCYCLONE AND TORNADO POTENTIAL TO INCREASE AS STORMS MOVE NEWD
   AND CROSS THIS BOUNDARY WHERE LOW LEVEL SHEAR AND HELICITY ARE
   ENHANCED. THREAT FOR ISOLATED TORNADOES IS EXPECTED TO CONTINUE NEXT
   FEW HOURS...MAINLY FROM S CNTRL THROUGH ERN AL. INSTABILITY BECOMES
   MORE MARGINAL AND ELEVATED FARTHER EAST INTO GA...AND THIS COULD
   SERVE TO LIMIT THE EWD PROGRESSION OF THE TORNADO THREAT.
   
   ..DIAL.. 11/29/2005
   
   
   ATTN...WFO...FFC...TAE...BMX...MOB...
   
   31408584 31908703 33408607 33688521 33058491

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2505
   NWS STORM PREDICTION CENTER NORMAN OK
   1028 PM CST MON NOV 28 2005
   
   AREAS AFFECTED...S CNTRL THROUGH E CNTRL AL AND WRN AND NW GA
   
   CONCERNING...TORNADO WATCH 886...
   
   VALID 290428Z - 290530Z
   
   TORNADO WATCH 886 WILL BE ALLOWED TO EXPIRE AT 05Z. A LIMITED THREAT
   OF SEVERE WEATHER MAY PERSIST BEYOND 05Z ACROSS SRN AND E CNTRL AL
   THROUGH WRN AND NW GA. HOWEVER...OVERALL TREND SHOULD BE FOR THE
   THREAT TO GRADUALLY DIMINISH WITH TIME.
   
   LATE THIS EVENING A LINE OF THUNDERSTORMS CONTINUES FROM NWRN GA
   SWWD THROUGH S CNTRL AL. THE LINE WILL CONTINUE SLOWLY EAST THROUGH
   ERN AL AND INTO WRN GA THE REMAINDER OF THE EVENING AND INTO THE
   EARLY MORNING HOURS. LOW LEVEL SHEAR REMAINS STRONG ACROSS ERN AL
   AND WRN GA N OF SURFACE BOUNDARY THAT EXTENDS FROM THE FL PANHANDLE
   NWWD INTO SRN AL. SOME POTENTIAL STILL EXISTS FOR ORGANIZED STORM
   STRUCTURES WITH ISOLATED DAMAGING WIND OR A BRIEF TORNADO WITHIN THE
   LINE. HOWEVER...MOST STORMS ARE PROBABLY BECOMING INCREASINGLY
   ELEVATED WITH TIME. THE PRIMARY LIMITING FACTOR FOR A MORE ROBUST
   SEVERE THREAT APPEARS TO BE WEAK SURFACE BASED INSTABILITY WHICH
   SHOULD BECOME INCREASINGLY MARGINAL AS THE BOUNDARY LAYER CONTINUES
   TO COOL.
   
   ..DIAL.. 11/29/2005
   
   
   ATTN...WFO...FFC...TAE...BMX...MOB...
   
   31378602 31988641 34438469 33888414 31668509

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2506
   NWS STORM PREDICTION CENTER NORMAN OK
   1041 PM CST MON NOV 28 2005
   
   AREAS AFFECTED...CNTRL FL PANHANDLE
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 290441Z - 290615Z
   
   CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE WW OVER THE
   CNTRL FL PANHANDLE.
   
   LATE THIS EVENING...A SURFACE BOUNDARY EXTENDS FROM THE NRN FL
   PENINSULA NWWD ACROSS THE EXTREME NERN GULF. STORMS CONTINUE TO
   DEVELOP OVER THE NERN GULF AND ARE TRAINING NEWD. THE STORMS APPEAR
   TO TAKE ON SUPERCELL CHARACTERISTICS AS THEY CROSS THE BOUNDARY
   WHERE LOW LEVEL SHEAR IS ENHANCED...BEFORE WEAKENING AS THEY MOVE
   DEEPER INTO THE COOLER BOUNDARY LAYER N OF THIS FEATURE. THIS
   BOUNDARY APPEARS TO HAVE SHIFTED NWD LAST COUPLE HOURS. THERE IS
   SOME CONCERN THAT EVENTUALLY STORMS WILL BE ABLE TO MAINTAIN THEIR
   INTENSITY INLAND AS THE BOUNDARY MOVES ONSHORE. PRIMARY THREAT WILL
   BE ISOLATED TORNADOES.
   
   ..DIAL.. 11/29/2005
   
   
   ATTN...WFO...TAE...
   
   29978338 29748412 30308461 30938387 30638342

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2507
   NWS STORM PREDICTION CENTER NORMAN OK
   0448 AM CST TUE NOV 29 2005
   
   AREAS AFFECTED...COASTAL AREAS OF THE WRN FL PENINSULA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 291048Z - 291245Z
   
   ISOLATED SEVERE STORMS WILL BE POSSIBLE AS THUNDERSTORMS...NOW OVER
   THE ERN GULF...CONTINUE TO MOVE EWD TOWARD THE WRN FL COAST THIS
   MORNING.
   
   NUMEROUS THUNDERSTORMS ACROSS THE ERN GULF LOOP CURRENT HAVE BEEN
   ACTIVE OVERNIGHT...GIVEN AVAILABLE BOUNDARY LAYER MOISTURE
   MAINTAINING STRONG INSTABILITY.  35-45 KT OF DEEP LAYER SHEAR WITHIN
   THIS AIR MASS HAS RESULTED IN ORGANIZED STRUCTURES/SUPERCELLS PER
   REGIONAL RADAR DATA.  AIR MASS ALONG THE COAST OF WRN FL IS MOIST
   WITH SURFACE DEWPOINTS IN THE MID-UPPER 60S.  HOWEVER...WEAK
   INSTABILITY PER WEAK LOW-LEVEL LAPSE RATES IS EXPECTED TO LIMIT THE
   INLAND POTENTIAL FOR STORMS TO REMAIN SURFACE BASED...AND THUS
   LIKELY PRECLUDE AN INLAND SEVERE THREAT.
   
   ..PETERS.. 11/29/2005
   
   
   ATTN...WFO...MFL...TBW...JAX...TAE...
   
   29228345 29498335 29588288 29098243 28398220 27818218
   26938175 26308158 26128202 27168280 28168322

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2508
   NWS STORM PREDICTION CENTER NORMAN OK
   0450 AM CST TUE NOV 29 2005
   
   AREAS AFFECTED...SC / GA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 291050Z - 291215Z
   
   WE ARE MONITORING THE AREA FOR AN UPWARD TREND IN CONVECTIVE
   INTENSITY. IF THIS OCCURS...A TORNADO WATCH COULD BE REQUIRED.
   
   AIR MASS AHEAD OF COLD FRONT REMAINS MARGINALLY UNSTABLE FOR SEVERE
   CONVECTION...ALTHOUGH DEWPOINTS HAVE INCREASED INTO THE MID TO UPPER
   60S WITH TEMPERATURES HOLDING NEAR 68-72 F. MODIFIED FORECAST
   SOUNDINGS INDICATE SURFACE BASED CAPE EXISTS WITH LITTLE
   CIN...ESPECIALLY OVER SRN GA / NRN FL WHERE INSTABILITY IS GREATEST.
   
   GIVEN GENERALLY WEAK FORCING ALONG DRIFTING COLD FRONT AND WITH
   UPPER SUPPORT FOR ASCENT LIFTING N OF THE AREA...EXPECT ONLY
   ISOLATED COVERAGE OF SEVERE. STORMS THAT CAN DEVELOP RELATIVELY
   STRONG CORES WILL LIKELY EXHIBIT ROTATION AND COULD PRODUCE AN
   ISOLATED TORNADO WITH 0-1 SRH VALUES OF 150-250 M2/S2. GREATEST
   THREAT FOR EITHER DAMAGING WINDS AND/OR TORNADO WOULD BE WITHIN
   SURFACE THETA-E AXIS.
   
   ..JEWELL.. 11/29/2005
   
   
   ATTN...WFO...ILM...CHS...CAE...GSP...JAX...FFC...TAE...
   
   30778436 32098366 33258318 34008214 34608102 34538005
   33827977 32708075 31738122 30128141 30258302 30338428

[CaptinCrunch]

MESOSCALE DISCUSSION 2509
NWS STORM PREDICTION CENTER NORMAN OK
0656 AM CST TUE NOV 29 2005

AREAS AFFECTED...MUCH OF SC/PARTS OF WRN AND CENTRAL NC TO SWRN VA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 291256Z - 291500Z



AIR MASS IS EXPECTED TO BECOME CONDUCIVE FOR NEW THUNDERSTORM
DEVELOPMENT/ATTENDANT SEVERE THREAT...POTENTIALLY BY MID MORNING...
FROM SWRN/SRN VA SWD ACROSS WRN/CENTRAL NC AND MUCH OF SC.

LIGHTNING DATA DURING THE LAST HOUR HAS SHOWN A DECREASING TREND IN
OVERALL CG LIGHTNING ACROSS THE AREA OF CONCERN. HOWEVER...
THUNDERSTORMS ARE EXPECTED TO REDEVELOP THIS MORNING ACROSS THE AREA
OF CONCERN IN ADVANCE OF COLD FRONT.

STRONG WIND FIELDS/SHEAR ARE VERY SUPPORTIVE OF ORGANIZED SEVERE
STORMS WITH PRIMARY THREATS BEING FROM DAMAGING WINDS AND TORNADOES.
ALTHOUGH INSTABILITY IS WEAK ATTM...THUS SUPPORTING THE DECREASE IN
LIGHTNING COVERAGE...12Z GSO SOUNDING MODIFIED FOR SURFACE
CONDITIONS OVER SC RESULTS IN SBCAPE UP TO 1400 J/KG WITH VERY
LITTLE CIN. DESPITE LIMITED SURFACE HEATING PER CLOUDINESS...SMALL
RISES IN SURFACE TEMPERATURE AND MOISTURE VALUES PER ADVECTION WILL
SUPPORT A SEVERE THREAT WITH NEW THUNDERSTORM DEVELOPMENT EXPECTED
IN ADVANCE OF THE COLD FRONT THIS MORNING.

[CaptinCrunch]

MESOSCALE DISCUSSION 2510
NWS STORM PREDICTION CENTER NORMAN OK
0109 PM CST TUE NOV 29 2005

AREAS AFFECTED...ERN SC...NC...VA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 291909Z - 292115Z



AREAS EAST OF SLOW MOVING COLD FRONT ARE BEING MONITORED FOR AN
INCREASE IN STRONG TO SEVERE STORMS THIS AFTERNOON. A WATCH MAY BE
ISSUED FOR PORTIONS OF THE ERN CAROLINAS AND PERHAPS PARTS OF SRN VA
WITHIN AN HOUR OR SO IF STORM INTENSITY CONTINUES TO INCREASE.

A NARROW LINE OF LOW-TOPPED CONVECTION HAS RECENTLY DEVELOPED FROM
30W GSO TO 10N CAE. MEANWHILE...A STRONG MID/UPPER LEVEL IMPULSE
WITHIN JET ENTRANCE REGION WAS SPREADING ENEWD ACROSS THE SRN
APPALACHIANS. EXPECT THIS IMPULSE WILL CONTRIBUTE TO DEEPENING THE
FRONTAL CIRCULATION ACROSS THE CAROLINAS AND VA THROUGH EVENING.

AIR MASS AHEAD OF THE FRONT WAS MOIST AND MARGINALLY UNSTABLE WITH
WEAK LAPSE RATES RESULTING IN LITTLE MORE THAN ABOUT 500 J/KG MLCAPE
ACROSS THE REGION. HOWEVER...THE PROSPECTS FOR STRENGTHENING FORCING
AND EFFECTIVE SHEAR VALUES AROUND 50KT ARE EXPECTED TO PARTIALLY
COMPENSATE FOR THE LIMITED INSTABILITY AND MIGHT SUPPORT A GRADUALLY
INTENSIFYING LINE OF TSTMS MOVING EAST FROM THE PIEDMONT AREAS OVER
THE NEXT FEW HOURS. LATEST VWP DATA WAS DEPICTING MODEST SELY SFC
FLOW TOPPED BY 50KT SLY FLOW AT 1KM. RESULTING LOW LEVEL SHEAR IS
MORE THAN ADEQUATE FOR MESOCYCLONES. IF STORMS CONTINUE TO INTENSIFY
NEAR THE FRONT...THE POTENTIAL FOR LINE SEGMENTS AND SHORT-LIVED
MESOCYCLONES WITH DAMAGING WINDS COULD EVOLVE AND SPREAD EAST
THROUGH EVENING.

[Brent]

MESOSCALE DISCUSSION 2521
NWS STORM PREDICTION CENTER NORMAN OK
0935 PM CST SAT DEC 03 2005

AREAS AFFECTED...SWRN TN...SERN AR...NRN/CENTRAL MS...SWRN/SRN
MIDDLE TN

CONCERNING...SEVERE THUNDERSTORM POTENTIAL

VALID 040335Z - 040530Z

CONVECTION APPEARS TO DEVELOPING ALONG THE SEWD MOVING FRONT OVER
EXTREME NWRN MS...AND OVER PARTS OF SWRN AR. WW WILL LIKELY BE
NEEDED BY 04Z.

AIRMASS AHEAD OF THE FRONT IS WARM/MOIST WITH TEMPERATURES NEAR 70F
AND DEW POINTS OF 60-65F. STRONG WSWLY WINDS ALOFT /500 MB FLOW OF
50-70 KT/ AND VEERING PROFILES IN THE LOWEST 1.5-2 KM AGL ARE
CREATING A FAVORABLE ENVIRONMENT FOR ROTATING STORMS GIVEN
PERSISTENT UPDRAFTS. 00Z ETA AND 02Z RUC BOTH INDICATE ADDITIONAL
THUNDERSTORM DEVELOPMENT ALONG THE FRONT INTO THE OVERNIGHT HOURS.
A NEW WATCH WILL LIKELY BE NEEDED TO BE ISSUED BY 04Z.

..WEISS.. 12/04/2005

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2524
   NWS STORM PREDICTION CENTER NORMAN OK
   0200 AM CST SUN DEC 04 2005
   
   AREAS AFFECTED...NRN LA...SERN AR...N CNTRL MS...NRN AND CNTRL AL
   AND SERN TN
   
   CONCERNING...TORNADO WATCH 889...
   
   VALID 040800Z - 040930Z
   
   NRN PORTION OF SQUALL LINE FROM SERN TN THROUGH NERN AL IS EXPECTED
   TO GRADUALLY WEAKEN AS IT MOVES INTO NWRN GA. THE SWRN TWO THIRDS OF
   THE LINE SHOULD CONTINUE TO DEVELOP SEWD. CONVECTIVE TRENDS WILL BE
   MONITORED FOR A POSSIBLE WW ACROSS PARTS OF CNTRL AL.
   
   EARLY THIS MORNING A SQUALL LINE EXTENDS FROM SERN TN SWWD THROUGH
   NRN AL AND FARTHER SW INTO N CNTRL MS. A WARM/WEDGE FRONT EXTENDS
   FROM CNTRL GA NWWD THROUGH NERN AL WHERE IT INTERSECTS THE SQUALL
   LINE. STRONGEST PORTION OF THE LINE IS CURRENTLY MOVING THROUGH NRN
   AL WHERE SIGNIFICANT WIND DAMAGE HAS BEEN REPORTED. HOWEVER...NRN
   THIRD OF THE LINE SHOULD WEAKEN AND BECOME MORE ELEVATED AS IT
   CROSSES THE WEDGE FRONT AND MOVES OVER A MUCH MORE STABLE BOUNDARY
   LAYER IN NRN GA AND SE TN WHERE TEMPERATURES ARE IN THE 40S. FARTHER
   SW STORMS WILL HAVE A MUCH WIDER WARM SECTOR TO TRAVERSE.
   HOWEVER...THE BOUNDARY LAYER FLOW IS EXPECTED TO GRADUALLY WEAKEN
   AND VEER WITH TIME AS THE LOW LEVEL JET SHIFTS NEWD AWAY FROM THE
   WARM SECTOR. THE WEAKENING AND VEERING BOUNDARY LAYER FLOW SHOULD
   RESULT IN A GRADUAL DECREASE IN CONVERGENCE AND MAY SERVE AS AN
   OVERALL LIMITING FACTOR FOR SEVERE WEATHER LATER THIS MORNING.
   NEVERTHELESS...CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED FOR A
   POSSIBLE WW OVER CNTRL AL AS STORMS APPROACH THE ERN EDGE OF WW 889.
   
   ..DIAL.. 12/04/2005
   
   
   ATTN...WFO...MRX...FFC...BMX...HUN...MEG...JAN...
   
   32999102 33668842 34418663 35088570 34758452 33898467
   32918602 32548860 32619089

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2525
   NWS STORM PREDICTION CENTER NORMAN OK
   0550 AM CST SUN DEC 04 2005
   
   AREAS AFFECTED...FAR SE PA/MUCH OF NJ/FAR NRN DE
   
   CONCERNING...WINTER MIXED PRECIPITATION
   
   VALID 041150Z - 041415Z
   
   A MIX OF FREEZING RAIN AND/OR SLEET MAY CONTINUE THROUGH 15Z ACROSS
   FAR SE PA/MUCH OF NJ/FAR NRN DE...INCLUDING THE PHILADELPHIA AND
   TRENTON METRO AREAS.
   
   LIGHT/OCNLY MDT PRECIPITATION SHIELD CONTINUES TO QUICKLY TRANSITION
   EWD ACROSS MUCH OF THE NORTHEAST/SRN NEW ENGLAND AHEAD OF LOW
   AMPLITUDE IMPULSE PER WATER VAPOR/IR SATELLITE IMAGERY. SIMILAR TO
   OBSERVATIONAL TRENDS OVER THE PAST SEVERAL HOURS...09Z RUC
   SOUNDINGS/P-TYPE ALGORITHMS SUGGESTS A MIX OF FREEZING RAIN AND/OR
   SLEET MAY CONTINUE UNTIL AROUND 15Z ACROSS FAR SE PA/MUCH OF NJ/FAR
   NRN DE. STRONG SWLY LOW LEVEL JET AND ASSOCIATED WAA PLUME IS
   SUPPORTING AN ELEVATED WARM LAYER INTO THIS REGION...FAVORABLE FOR
   AT LEAST PARTIAL MELTING WITH FREEZING RAIN AND/OR SLEET WHERE
   SURFACE TEMPERATURES REMAIN AROUND/BELOW 32F.
   
   ALTHOUGH FREEZING RAIN/SLEET WILL BE POSSIBLE IN THE SHORT
   TERM...SATELLITE/RADAR TRENDS DEPICT MID LEVEL DRY AIR QUICKLY
   APPROACHING THE AREA FROM THE WEST...WITH PRECIPITATION RATES
   EXPECTED TO DIMINISH ACCORDINGLY INTO MID MORNING.
   
   ..GUYER.. 12/04/2005
   
   
   ATTN...WFO...OKX...PHI...
   
   40977486 40837428 40357414 39847430 39407525 39647547
   40177558 40857530

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2526
   NWS STORM PREDICTION CENTER NORMAN OK
   1014 AM CST SUN DEC 04 2005
   
   AREAS AFFECTED...SWRN/CENTRAL LA INTO CENTRAL MS
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 041614Z - 041815Z
   
   SEVERE TSTM THREAT EXPECTED TO SLOWLY INCREASE THROUGH THE LATE
   MORNING/EARLY AFTERNOON.  WW MAY BE REQUIRED BY THE EARLY/MID
   AFTERNOON.
   
   THUNDERSTORMS HAVE INCREASED DURING THE PAST HOUR IN A NE-SW
   ORIENTED AXIS FROM NEAR HEZ TO JUST SOUTHWEST OF LCH.  12Z SOUNDINGS
   FROM JAN AND LCH INDICATE AIR MASS IS NOW ONLY WEAKLY CAPPED...IF AT
   ALL...GIVEN CURRENT SFC TEMPERATURES IN THE LOWER 70S F AND DEW
   POINTS IN THE UPPER 60S F.  MLCAPES ARE NOW IN THE 500-1000 J/KG
   RANGE...BUT WILL INCREASE INTO THE 1000-1500 J/KG BY THE MID
   AFTERNOON GIVEN FURTHER HEATING.  LATEST SURFACE ANALYSES INDICATES
   SURFACE WAVE FORMING ALONG THE FRONT NEAR LFK WHICH WILL LIKELY
   DEVELOP SLOWLY EWD INTO CENTRAL LA AS COLD FRONT CONTINUES MOVING
   SOUTHEAST.  THOUGH LARGE SCALE ASCENT ACROSS THE REGION WILL REMAIN
   WEAK...LOW LEVEL FOCUS ALONG FRONT AND NEAR MESO LOW SHOULD SUPPORT
   INCREASED THUNDERSTORM DEVELOPMENT ACROSS THIS GENERAL REGION. SWLY
   WINDS ALOFT ARE NOT EXPECTED TO STRENGTHEN TODAY OVER THIS
   AREA...HOWEVER EFFECTIVE SHEAR IS STILL ANTICIPATED TO BE SUFFICIENT
   FOR SUPERCELLS/SMALL BOW ECHOES WITH STRONGER CELLS IF INSTABILITY
   CAN DEVELOP AS EXPECTED.  THEREFORE...SEVERE THREAT SHOULD SLOWLY
   INCREASE THROUGH THE LATE MORNING AND WW MAY BECOME NECESSARY LATER
   TODAY.
   
   ..EVANS.. 12/04/2005
   
   
   ATTN...WFO...JAN...LIX...LCH...SHV...
   
   29649341 30149415 31079349 31709144 31928984 30858957
   29999135

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2527
   NWS STORM PREDICTION CENTER NORMAN OK
   1224 PM CST SUN DEC 04 2005
   
   AREAS AFFECTED...AL INTO WRN GA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL
   
   VALID 041824Z - 042000Z
   
   THE THREAT OF ISOLATED LARGE HAIL AND DAMAGING WINDS SHOULD INCREASE
   ALONG AND SOUTH OF SURFACE FRONT ACROSS THE AREA THIS AFTERNOON.
   TRENDS ARE BEING MONITORED FOR A WW.
   
   SATELLITE IMAGERY AND 18Z SURFACE ANALYSES INDICATE STRONG
   TEMPERATURE/HEATING GRADIENT ACROSS CENTRAL AL INTO NRN/CENTRAL GA.
   WELL DEFINED SURFACE FRONT IS EXPECTED TO CONTINUE SHIFTING SLOWLY
   SSEWD THROUGH THE DAY...WITH TEMPERATURES APPROACHING 80F TO ITS
   SOUTH. REGION REMAINS ALONG NERN EXTENT OF PRIMARY LOW LEVEL
   MOISTURE AXIS EXTENDING OUT OF THE LOWER MS RIVER VALLEY WITH
   SURFACE DEW POINTS IN THE LOWER 60S F. THIS IS LIMITING AVAILABLE
   INSTABILITY WITH CURRENT MLCAPES LESS THAN 1000 J/KG.  HOWEVER...
   STRONG HEATING WITHIN WARM SECTOR WILL STEEPEN LOW LEVEL LAPSE RATES
   AND DEEP LAYER SHEAR REMAINS MORE THAN ADEQUATE FOR ORGANIZED STORMS
   INCLUDING SUPERCELLS/SMALL BOW ECHOES. THE POTENTIAL FOR
   ORGANIZED/SUSTAINED UPDRAFTS AND STEEP LOW LEVEL LAPSE RATES MAY
   OVERCOME LIMITED INSTABILITY AND SUPPORT MARGINALLY SEVERE HAIL AND
   ISOLATED DAMAGING WINDS.  SEVERE THUNDERSTORM WATCH BEING CONSIDERED
   FOR PART OF THIS REGION.
   
   ..EVANS.. 12/04/2005
   
   
   ATTN...WFO...FFC...TAE...BMX...MOB...
   
   33338829 34098426 32818350 31918507 31398825

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2528
   NWS STORM PREDICTION CENTER NORMAN OK
   0211 PM CST SUN DEC 04 2005
   
   AREAS AFFECTED...FAR SERN TX...LA...CENTRAL MS
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 890...
   
   VALID 042011Z - 042215Z
   
   SEVERE THUNDERSTORMS WILL CONTINUE DEVELOPING WEST TO EAST ACROSS WW
   INTO THE EARLY EVENING.  CONTINUE VALID PORTION OF WW.
   
   19Z SURFACE ANALYSIS INDICATES SURFACE COLD FRONT HAS PROGRESSED
   SOUTH-SOUTHEASTWARD THIS AFTERNOON AND EXTENDS FROM NEAR MEI SWWD TO
   JUST OFF THE FAR SOUTHEAST TX COAST.  INTERMITTENT SUPERCELL AND
   SMALL BOW ECHO STRUCTURES HAVE DEVELOPED ALONG BROKEN LINE OF STORMS
   NOW EXTENDING FROM CENTRAL LA INTO FAR SERN TX.
   
   AIR MASS REMAINS MODERATELY UNSTABLE FROM THE LOWER SABINE RIVER
   INTO CENTRAL LA WHERE RICHER GULF MOISTURE AND WARMER TEMPERATURES
   HAVE DEVELOPED.  SURFACE-BASED CAPES OVER THIS AREA ARE CURRENTLY IN
   EXCESS OF 1000 J/KG...WITH MORE MARGINAL INSTABILITY NOW INTO
   CENTRAL MS.  SHEAR ACROSS THE WHOLE REGION REMAINS QUITE
   STRONG...WITH EFFECTIVE SHEAR FROM 40-50 KT ACCORDING TO REGIONAL
   VWP/S. SEASONABLY COOL MID LEVEL TEMPERATURES WILL SUSTAIN A THREAT
   OF LARGE HAIL...ESPECIALLY WITHIN SWRN PORTION OF WW WHERE GREATER
   INSTABILITY SHOULD SUPPORT HAIL TO GOLF BALL SIZE IN THE STRONGER
   CORES. THE THREAT OF MARGINALLY SEVERE HAIL WILL ALSO CONTINUE
   BEHIND SURFACE COLD FRONT ACROSS NORTHERN PORTIONS OF WW /AND
   ADJACENT AREAS/ ALONG NOSE OF SWLY 35-40 KT LLJ.  DAMAGING WINDS
   WILL ALSO REMAIN A HAZARD AS SMALL LINES EVOLVE IN A MORE N-S
   ORIENTATION ALONG AND AHEAD OF THE FRONT.
   
   ..EVANS.. 12/04/2005
   
   
   ATTN...WFO...BMX...MOB...JAN...LIX...LCH...SHV...
   
   28729404 30529398 33568824 31318833

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2529
   NWS STORM PREDICTION CENTER NORMAN OK
   0330 PM CST SUN DEC 04 2005
   
   AREAS AFFECTED...CENTRAL AND NRN AL/GA INTO CENTRAL SC
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 891...
   
   VALID 042130Z - 042300Z
   
   THREAT FOR SEVERE THUNDERSTORMS...INCLUDING ISOLATED
   SUPERCELLS...EXPECTED TO CONTINUE ACROSS WW.  ISOLATED SEVERE THREAT
   ALSO EXPECTED TO PERSIST JUST EAST OF WW ACROSS THE SAVANNAH RIVER
   VALLEY.  CONTINUE WW.
   
   THOUGH LARGE SCALE ASCENT REMAINS WEAK ACROSS THE
   REGION...SEASONABLY WARM/MOIST BOUNDARY LAYER HAS DEVELOPED AHEAD OF
   A COLD FRONT NOW MOVING SEWD ACROSS NRN GA INTO CENTRAL AL.  DEW
   POINTS REMAIN IN THE LOWER 60S OVER MUCH OF THE SEVERE TSTM
   WATCH...WITH AXIS OF NEAR 60F DEW POINTS SPREADING INTO AGS DURING
   THE PAST HOUR OR TWO.  DEEP LAYER SHEAR REMAINS QUITE STRONG WITH
   EFFECTIVE SHEAR FROM 45-55 KT ACROSS THE REGION...AND WILL SUSTAIN A
   FEW SUPERCELLS WITH PRIMARY THREATS OF LARGE HAIL/DAMAGING WINDS.
   SHEAR AND INSTABILITY PARAMETERS INDICATE THE SEVERE THREAT WILL
   LIKELY CONTINUE AHEAD OF THE COLD FRONT INTO E-CENTRAL GA/FAR WRN SC
   THROUGH SUNSET.  WE WILL NEED TO MONITOR THIS AREA INTO THE EARLY
   EVENING FOR AN ADDITIONAL WW.
   
   ..EVANS.. 12/04/2005
   
   
   ATTN...WFO...CHS...CAE...GSP...FFC...BMX...HUN...MOB...
   
   31668818 33848766 34368197 33658077 32208266

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2530
   NWS STORM PREDICTION CENTER NORMAN OK
   0545 PM CST SUN DEC 04 2005
   
   AREAS AFFECTED...SE LA...SRN MS...SRN AL...FAR WRN FL PANHANDLE
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 890...
   
   VALID 042345Z - 050145Z
   
   AN ISOLATED SEVERE POTENTIAL MAY CONTINUE AS A CONVECTIVE CLUSTER
   MOVES EWD ACROSS SRN MS AND SRN AL THIS EVENING. A REPLACEMENT WW
   MAY BE REQUIRED ACROSS THE REGION.
   
   SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT EXTENDING ENEWD JUST NORTH
   OF A LINE FROM NEAR BATON ROUGE LA TO NEAR HATTIESBURG MS TO
   MONTGOMERY AL. SFC DEWPOINTS SOUTH OF THE FRONT ARE IN THE LOWER TO
   MID 60S F AND DEWPOINTS MAY INCREASE OVER THE NEXT FEW HOURS DUE TO
   SLY WINDS. THIS COMBINED WITH LOW-LEVEL CONVERGENCE ALONG THE
   BOUNDARY MAY ALLOW A BOW ECHO AND CONVECTIVE CLUSTER CURRENTLY ALONG
   THE MS-LA STATE-LINE TO CONTINUE FOR 3 TO 5 MORE HOURS. AS A
   RESULT...THE POTENTIAL FOR SEVERE STORMS MAY INCREASE OVER FAR SRN
   MS AND SRN AL INTO THE FL PANHANDLE. 0-6 KM SHEAR VALUES AROUND 45
   KT WITH INCREASING LOW-LEVEL FLOW DUE TO THE STRENGTHENING LOW-LEVEL
   JET SHOULD BE SUFFICIENT FOR AT LEAST A MARGINAL SEVERE THREAT WITH
   ISOLATED WIND DAMAGE AND HAIL POSSIBLE WITH THE STRONGER CELLS.
   HOWEVER...WITH THE LOSS OF DAYTIME HEATING...THE MAGNITUDE OF THE
   SEVERE THREAT REMAINS QUESTIONABLE.
   
   ..BROYLES.. 12/04/2005
   
   
   ATTN...WFO...BMX...MOB...JAN...LIX...LCH...
   
   30689171 31379055 31958851 32078712 31598652 30918642
   30118705 29798923 29869132 30029151

[TexasStooge]

Code: Select all

   MESOSCALE DISCUSSION 2531
   NWS STORM PREDICTION CENTER NORMAN OK
   0635 PM CST SUN DEC 04 2005
   
   AREAS AFFECTED...NRN NY
   
   CONCERNING...HEAVY SNOW
   
   VALID 050035Z - 050630Z
   
   ...SNOW RATES WILL BE AT LEAST 2 INCHES PER HOUR WITHIN MOST INTENSE
   PORTIONS OF LAKE EFFECT BAND DOWNWIND OF LAKE ONTARIO...
   
   LOCAL RADAR LOOPS INDICATE HEAVY SNOW IS ONGOING ACROSS OSWEGO AND
   LEWIS COUNTIES IN NRN NY SOUTH OF WATERTOWN. 00Z SOUNDING FROM
   BUFFALO INDICATES A FAVORABLE UNIDIRECTIONAL WIND PROFILE WITH
   WESTERLIES INCREASING TO AROUND 40-45 KT NEAR 700MB. WINDS WITHIN
   THE 850-700MB LAYER WILL CHANGE LITTLE IN DIRECTION OVER THE NEXT
   FEW HOURS...AND THIS WILL MAINTAIN A SINGLE BUT INTENSE BAND OF
   HEAVY SNOW. FORECAST GUIDANCE FROM THE SHORT TERM MODELS SUGGESTS
   THE BAND MAY FLUCTUATE A LITTLE TO THE NORTH OR SOUTH...BUT
   BASICALLY WILL REMAIN OVER OSWEGO/SRN LEWIS COUNTIES...AND POSSIBLY
   NRN ONEIDA. THE RUC AND 4KM WRF/NMM BOTH HINT THAT HEAVY SNOW BANDS
   WILL PERSIST THROUGH THE OVERNIGHT HOURS.
   
   ..TAYLOR.. 12/05/2005
   
   
   ATTN...WFO...BTV...ALY...BGM...BUF...
   
   43157632 43287745 43837723 44317513 44087418 42987451
   42927487