[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 031251
SWODY1
SPC AC 031249

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0749 AM CDT MON APR 03 2006

VALID 031300Z - 041200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PORTIONS OF THE ERN
CAROLINAS INTO SERN VA TODAY AND EARLY THIS EVENING...

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF AL/GA NWD INTO
THE UPPER OH RIVER VALLEY AND MID ATLANTIC...

...DELMARVA INTO PORTIONS OF THE SOUTHEAST...
SIGNIFICANT MID/UPPER LEVEL TROUGH NOW DIGGING EWD ACROSS THE MID
SOUTH WILL EJECT RAPIDLY ENEWD ACROSS THE CENTRAL/SRN APPALACHIANS
TODAY. ASSOCIATED 70+ KT MID LEVEL JET IS FORECAST BY ALL THE
MODELS TO OVERSPREAD NRN/ERN GA AND CENTRAL SC THROUGH 21Z...
MAINTAINING ENHANCED LARGE SCALE ASCENT AND VERY STRONG SHEAR ACROSS
THIS REGION.  IN ADDITION...PLUME OF ELEVATED-MIXED LAYER AIR HAS
OVERSPREAD MUCH OF THE SOUTHEAST AND WILL FEED NEWD INTO THE
CAROLINAS TODAY.  TLH AND JAX BOTH INDICATE 8+ C/KM LAPSE RATES FROM
H7-H5...WITH 7+ C/KM AT CHS.  COMBINED WITH VERY STRONG ASCENT AND
STRENGTHENING SHEAR...A SIGNIFICANT SEVERE THUNDERSTORM THREAT IS
EXPECTED TO UNFOLD INTO THE CENTRAL/ERN CAROLINAS INTO SERN VA
TODAY.

MCS CONTINUES FROM SUNDAY EVENINGS SEVERE EVENT INTO THE SRN
APPALACHIANS THIS MORNING...WHICH WILL LIKELY CONTINUE SPREADING EWD
INTO THE PIEDMONT/CENTRAL GA EARLY TODAY.  ACTIVITY HAS WEAKENED
OVER THE PAST HOUR OR TWO AS CONSOLIDATED OUTFLOW BOUNDARY CONTINUES
TO UNDERCUT STRONGER STORMS.  HOWEVER...VERY STEEP LAPSE RATES IN
PLACE THIS MORNING AND 40-50 KT EFFECTIVE SHEAR WILL MAINTAIN A
THREAT OF LARGE HAIL AND ISOLATED DAMAGING WINDS INTO THE MID
MORNING WITH THIS ACTIVITY.  BY 18Z...STORMS WILL INTENSIFY FROM
CENTRAL VA INTO CENTRAL SC ALONG REMNANTS OF THIS OUTFLOW BOUNDARY
AND/OR AHEAD OF APPROACHING SURFACE COLD FRONT NOW OVER CENTRAL
KY/TN. FORECAST SOUNDINGS INDICATE MLCAPE WILL EXCEED 1500 J/KG
INTO THE PIEDMONT...WHERE STRONG LOW AND DEEP LAYER SHEAR AND STEEP
LAPSE RATES WILL ENHANCE STORM SCALE ORGANIZATION.  ACTIVITY WILL
QUICKLY EVOLVE INTO SUPERCELL AND SMALL BOW ECHO STRUCTURES AND RACE
EWD THROUGH THE EARLY EVENING. VERY LARGE HAIL AND TORNADOES ARE
EXPECTED TO ACCOMPANY THESE STORMS.  TORNADO THREAT MAY BE ENHANCED
NEAR E-W ORIENTED OUTFLOW BOUNDARY FROM EARLIER STORMS NOW OVER
PORTIONS OF SERN NC.  WIND DAMAGE THREAT MAY ALSO BECOME WIDESPREAD
AS BROKEN SQUALL LINE EVOLVES LATER TODAY.

...ERN OH INTO WRN PA/NRN WV...
VERY STRONG LARGE SCALE ASCENT AHEAD OF SURFACE COLD FRONT AND
INTENSE MID/UPPER LEVEL TROUGH WILL INTERACT WITH LOWER TO MID 50F
SURFACE DEW POINTS OVER THE UPPER OH RIVER VALLEY/LOWER GREAT LAKES
THIS MORNING. MODIFIED 12Z SOUNDING AT ILN INDICATED MID/UPPER 60F
SURFACE TEMPERATURES WILL SUPPORT MARGINAL SURFACE BASED
INSTABILITY.  IN ADDITION...VERY STEEP LAPSE RATES AND SIGNIFICANT
LOW AND DEEP LAYER SHEAR SHOULD SUPPORT LOW TOPPED SEVERE
THUNDERSTORMS...POSSIBLY DEVELOPING BY THE MID MORNING.  THIS
ACTIVITY WILL POSE DAMAGING WINDS/LARGE HAIL THREATS EWD TOWARDS THE
APPALACHIANS...WITH ISOLATED TORNADOES ALSO POSSIBLE.

...CENTRAL GULF COAST STATES INTO ERN TX...
AIR MASS WILL REMAIN VERY UNSTABLE ALONG AND SOUTH OF SURFACE COLD
FRONT FORECAST TO MOVE SWD INTO CENTRAL/SRN MS AND SRN LA/ERN TX
THIS AFTERNOON.  THOUGH CAPPING WILL REMAIN PROBLEMATIC FOR
INITIATION GIVEN LACK OF LARGE SCALE ASCENT...HEATING AND
CONVERGENCE MAY ALLOW A FEW STORMS TO DEVELOP LATER TODAY.  JAN/S
12Z SOUNDING REMAINS VERY FAVORABLE FOR SEVERE THUNDERSTORMS...
SHOULD ACTIVITY DEVELOP IN GENERAL SUBSIDENT REGIME.  THEREFORE...
AT LEAST LOW SEVERE PROBABILITIES WARRANTED WSWWD ALONG THIS
BOUNDARY INTO PORTIONS OF ERN TX.

..EVANS/JEWELL.. 04/03/2006