[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 210544
SWODY1
SPC AC 210542

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1142 PM CST SUN NOV 20 2005

VALID 211200Z - 221200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 70 WSW
CTY 20 NNW GNV 30 NNW SSI 25 NNE SAV 20 SE OGB 20 SSW FAY 15 ENE GSB
50 ESE ORF.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 SSW BVE 35 NNW GZH
20 SW GSP 30 SW DOV 40 ESE NEL ...CONT... 40 ESE ISP 50 ESE PSM.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN NC/SC SWD ALONG GA
COAST TO FL...

...SYNOPSIS...
DEEPENING LONG WAVE TROUGH IS EXPECTED TO EVOLVE OVER THE ERN U.S.
THIS FORECAST PERIOD.  CLOSED LOW/SHORT WAVE TROUGH INITIALLY
LOCATED OVER THE LOWER MS VALLEY WILL TRACK EWD TO THE SERN
STATES...THEN BECOME NEGATIVELY TILTED TONIGHT AS IT TRACKS TOWARD
THE MID ATLANTIC STATES.  THIS TROUGH WILL INDUCE RAPID CYCLOGENESIS
AS A SURFACE LOW TRACKS FROM NWRN FL TO NERN NC BY 22/00Z...AND THEN
TO CAPE COD BY END OF THE PERIOD.  MODELS CONTINUE TO SUGGEST
ANOTHER SURFACE LOW MAY BE LOCATED ALONG THE SC COAST NEAR CHS AT
12Z THIS MORNING...WITH THIS LOW AND THE NWRN FL LOW CONSOLIDATING
INTO A PRIMARY LOW BY THIS EVENING ALONG THE DELMARVA COAST.

...GA COAST NEWD ACROSS ERN SC/NC...
AN EXTENSIVE AREA OF PRECIPITATION WITH EMBEDDED THUNDERSTORMS IS
EXPECTED TO BE ONGOING AT 12Z THIS MORNING FROM NRN FL NNEWD ACROSS
GA AND THE CAROLINAS...WITHIN LOW-LEVEL WAA REGIME AND BROAD LARGE
SCALE ASCENT AHEAD OF LOWER MS VALLEY TROUGH.  ASSOCIATED CLOUDINESS
MAY TEND TO LIMIT HOW FAR INLAND THE COASTAL BOUNDARY WILL REACH
TODAY...BUT CURRENT OUTLOOK THINKING EXPECTS THIS BOUNDARY TO MOVE
ABOUT 50 MILES INLAND OVER ERN SC/NC.  ONE OR TWO SURFACE WAVES WILL
LIKELY TRACK NEWD ALONG THIS SURFACE FRONT WITH WARM SECTOR SURFACE
DEWPOINTS IN THE MIDDLE TO UPPER 60S.  DESPITE LIMITED SURFACE
HEATING AND MODEST LAPSE RATES...RICH BOUNDARY LAYER MOISTURE WILL
SUPPORT WARM SECTOR MUCAPES NEAR 1000 J/KG.

STRENGTHENING DEEP LAYER WINDS/SHEAR VALUES WILL SUPPORT AN
ORGANIZED SEVERE THREAT...GIVEN THE WARM SECTOR MOVES INLAND...AS IS
EXPECTED AT THIS TIME ACROSS ERN SC/NC.  FARTHER S...SEVERE STORMS
WILL ALSO BE POSSIBLE ALONG THE GA COAST AS THE TRAILING COLD FRONT
MOVES ACROSS THIS REGION BY MID-LATE AFTERNOON.  PROGGED LOW LCLS
AND INCREASING LOW LEVEL SHEAR ALONG THE SURFACE BOUNDARY AND NEWD
MOVING SURFACE LOWS SHOULD RESULT IN A THREAT FOR TORNADOES...BEFORE
THIS ACTIVITY MOVES OFF THE COAST THIS EVENING.  

...FL PENINSULA...
SRN EXTENT OF THE TRAILING COLD FRONT IS EXPECTED TO SWEEP ACROSS
MUCH OF FL BY LATE THIS AFTERNOON AND THEN OFFSHORE THE SRN PART OF
THE FL PENINSULA THIS EVENING. SURFACE DEWPOINTS IN THE UPPER 60S
TO AROUND 70 ARE ALREADY IN PLACE ACROSS THE FL PENINSULA AND
COMBINED WITH LIMITED SURFACE HEATING WILL SUPPORT MUCAPE VALUES
FROM 500-1000 J/KG.  DESPITE THE MARGINAL INSTABILITY...STRONG
UNIDIRECTIONAL WIND FIELDS WILL LIKELY SUPPORT ONE OR MORE LINES OF
STORMS MOVING EWD ACROSS THE PENINSULA TODAY.  THE PRIMARY LINE
SHOULD BE ALONG THE COLD FRONT.  DAMAGING WINDS WILL LIKELY BE THE
PRIMARY THREAT.  HOWEVER...SOME LOW-LEVEL HODOGRAPH CURVATURE MAY
SUPPORT A TORNADO THREAT AS WELL.

..PETERS/CROSBIE.. 11/21/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
WILL PROVIDE DETAILS ON THE TRANSITION.