[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 280539
SWODY1
SPC AC 280538

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1138 PM CST TUE DEC 27 2005

VALID 281200Z - 291200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 65 SSW
BVE 45 SSE MEI 35 SW 0A8 35 S ANB 15 N MCN 20 ESE VDI 25 NW JAX 10 W
OCF 45 WSW PIE.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 60 S 7R4 25 ESE JAN
35 SSE MKL 25 SE MDH BLV 20 E MTO 25 WNW LUK 20 N HTS 40 WSW BLF 20
NNW HKY 20 S ROA 25 NE LYH 20 W NHK 45 ESE ACY ...CONT... 35 E MLB
50 WSW FMY.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 NNW UIL 20 W CLM
15 SSW OLM 20 S PDX 40 S EUG 35 E 4BK 45 ENE ACV 15 E RBL 50 NNE SAC
35 ESE SAC 70 SW UKI.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS FAR SERN LA/MS TO MUCH
OF SRN AL/SRN GA/NRN FL INCLUDING THE PANHANDLE...

...SYNOPSIS...
MID/UPPER LEVEL TROUGH IS PROGGED TO TRACK FROM THE LOWER/MID MS
RIVER VALLEY ENEWD REACHING THE UPPER OH VALLEY TO SRN ATLANTIC
STATES BY 12Z THURSDAY.  TROUGH ORIENTATION IS EXPECTED TO BECOME
NEGATIVELY TILTED WITH STRONGEST MID TO HIGH LEVEL FLOW TRANSLATING
EWD FROM THE LOWER MS VALLEY ACROSS THE CENTRAL GULF COAST REGION TO
THE SERN STATES.

AT THE SURFACE...PRIMARY LOW IS EXPECTED TO TRACK FROM SRN IL NEWD
ALONG THE OH RIVER VALLEY...WITH SECONDARY CYCLOGENESIS IN LEE OF
THE SRN APPALACHIANS LATER IN THE PERIOD AS STRONGER HEIGHT FALLS
SPREAD TOWARD THE MID ATLANTIC COAST.  GIVEN PROGRESSIVE FLOW
ALOFT...COLD FRONT TRAILING SWD FROM THE PRIMARY SURFACE LOW WILL
SWEEP EWD ACROSS THE TN VALLEY AND GULF COAST STATES TODAY...
REACHING THE CAROLINAS TO THE NERN GULF OF MEXICO BY 12Z THU.

IN THE WEST...THE NEXT IN A SERIES OF PACIFIC TROUGHS WILL MOVE
QUICKLY ACROSS THE PAC NW TO THE NRN ROCKIES.  THE THREAT FOR
THUNDERSTORMS WITH THIS SYSTEM IS EXPECTED TO BE CONFINED TO MAINLY
COASTAL AREA OF WA/ORE AND NRN CA.

...NORTH CENTRAL GULF COAST STATES TO NRN FL/DEEP SOUTH...
SWLY LOW-LEVEL FLOW IS EXPECTED TO LIMIT THE INLAND INTRUSION OF
MORE SUBSTANTIAL GULF MOISTURE TODAY...WITH THE RICHEST BOUNDARY
LAYER MOISTURE LIKELY CONFINED TO WITHIN 150-200 NM FROM THE COAST. 
THIS MOISTURE ADVECTION WILL AID IN DESTABILIZING THE PRE-FRONTAL
WARM SECTOR THROUGH THE DAY WITH THE STRONGEST INSTABILITY EXPECTED
ACROSS MUCH OF THE SLIGHT RISK AREA WITH MUCAPE VALUES UP TO AROUND
1000 J/KG POSSIBLE.  WEAKER INSTABILITY IS EXPECTED FARTHER INLAND
WITH VALUES AOB 500 J/KG.

AT THE START OF THE PERIOD...THUNDERSTORMS ARE EXPECTED TO BE
ONGOING FROM PARTS OF THE LOWER OH RIVER VALLEY SWD TO SERN LA WITH
THE POTENTIAL FOR EMBEDDED STRONGER/SEVERE STORMS.  TSTMS ARE
EXPECTED TO BECOME MORE WIDESPREAD EARLY IN THE PERIOD AND SPREAD
EWD ALONG/AHEAD OF THE COLD FRONT AS STRONG DEEP-LAYER FORCING FOR
ASCENT AHEAD OF THE TROUGH OVERSPREADS THE LOW-LEVEL MOISTURE/
INSTABILITY AXIS.  DEEP LAYER SHEAR ORIENTED MORE NORMAL TO THE COLD
FRONT WILL SUPPORT BOTH EMBEDDED SUPERCELLS/LEWPS IN ADDITION TO
STORM-SCALE BOWS CAPABLE OF PRODUCING DAMAGING WINDS AND ISOLATED
TORNADOES.  THE GREATEST TORNADO THREAT IS EXPECTED TO BE FROM SRN
AL/FL PANHANDLE TO SWRN GA/NWRN FL AS A ZONE OF STRONG LOW-LEVEL
SHEAR /0-1 KM SRH VALUES RANGING FROM 200-300 M2/S2/ COMBINES WITH
THE STRONGER INSTABILITY.

SQUALL LINE IS EXPECTED TO SPREAD EWD ACROSS SRN GA/NRN FL THIS
EVENING WITH THE THREAT FOR DAMAGING WINDS AND PERHAPS ISOLATED
TORNADOES.  HOWEVER...OVERALL SEVERE THREAT SHOULD DIMINISH WITH
TIME AS THE STORMS ENCOUNTER GREATER STABILITY TO THE EAST.

..PETERS.. 12/28/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT WILL BE
DISCONTINUED ON 14 FEBRUARY 2006 BUT WILL REMAIN AVAILABLE
IN THE FOLLOWING PRODUCTS:

   WMO HEADER:       AWIPS ID:
   WUUS01            PTSDY1
   WUUS02            PTSDY2
   WUUS03            PTSDY3

A SERVICE CHANGE NOTICE ...SCN05-39... PROVIDES DETAILS
ON THE TRANSITION. FOR ADDITIONAL DETAILS SEE THE FOLLOWING
WEB ADDRESS USING LOWER CASE LETTERS:
WWW.NWS.NOAA.GOV/OM/NOTIF.HTM