[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 071936
SWODY1
SPC AC 071934

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0134 PM CST SUN JAN 07 2007

VALID 072000Z - 081200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE DEEP
SOUTH INTO THE SERN STATES/SERN MID-ATLANTIC REGIONS...

...SERN STATES...
A WEAK LEAD SHORTWAVE TROUGH CONTINUES TO SHEAR ENEWD ACROSS THE TN
VLY THIS AFTN AND IS LIKELY CONTRIBUTING TO THE RECENT INCREASE IN
CONVECTION/TSTMS FROM ERN TN SWWD INTO WCNTRL AL.  A MORE ROBUST
IMPULSE WAS QUICKLY MOVING SEWD THROUGH THE CNTRL/SRN PLAINS AND
WILL BECOME NEGATIVELY TILTED AS IT BEGINS TO EJECT EWD ACROSS THE
OH/TN VLYS LATER TONIGHT.

18Z SFC ANALYSIS SHOWS A 1010 MB LOW OVER SCNTRL KY WITH A WARM
FRONT REDEVELOPING NWD ALONG THE SRN EDGE OF THE APPALACHIANS.  A
VERY WARM AND MOIST BOUNDARY LAYER WAS FLOODING NWD AHEAD OF A COLD
FRONT SITUATED FROM THE LOW SWD ACROSS NWRN AL TO WEST OF THE NEW
ORLEANS AREA.  18Z BMX SOUNDING EXHIBITED AROUND 185 J/KG MLCAPES
WITH RATHER POOR LAPSE RATES.  THIS WAS RESULTING IN AN ENVIRONMENT
SUPPORTIVE OF A GRADUAL DEEPENING/STRENGTHENING OF MOIST CONVECTION 
AMIDST WEAK LARGE SCALE FORCING.

AS THE UPSTREAM PLAINS TROUGH SWINGS EWD TONIGHT AND MID-UPPER LEVEL
JET MAX ACCELERATES...FORCING FOR ASCENT WILL INCREASE THROUGH A
DEEPER LAYER AND CONVECTION SHOULD FURTHER STRENGTHEN ALONG/AHEAD OF
THE SEWD MOVING COLD FRONT OVERNIGHT.  THE COINCIDENT INCREASE IN
LOW-LEVEL FLOW WILL RESULT IN AN EROSION OF THE WEDGE FRONT AND
RAPID MOISTENING OF THE COLUMN DOWNSTREAM ACROSS THE SRN
APPALACHIANS AND THE CAROLINAS...SERN VA BY 12Z.

GIVEN THAT THE PRIMARY SFC LOW SHOULD REMAIN WEST OF THE APPALACHIAN
SPINE...STRONGEST VEERING WITH HEIGHT OF THE WIND FIELD SHOULD EXIST
ALONG THE WARM FRONT AS IT LIFTS NWD WITH TIME THIS
EVENING/OVERNIGHT.  HOWEVER...STRONG SPEED SHEAR SHOULD CONTINUE
OWING TO THE INCREASING LOW- AND MID-LEVEL WIND FIELDS OVERNIGHT
ACROSS THE WARM SECTOR.  AS A RESULT OF THE DESTABILIZATION...
INCREASED FORCING AND THE FAVORABLE VERTICAL SHEAR...ANY SUSTAINED
TSTM COULD BECOME SUPERCELLULAR...EITHER EMBEDDED WITHIN THE LINEAR
MCS OR AHEAD OF IT.  MAIN THREAT WILL BE DAMAGING WINDS...ALTHOUGH
BRIEF TORNADOES COULD ALSO OCCUR.

MAIN SEVERE WEATHER THREATS WILL OCCUR ACROSS PORTIONS OF THE DEEP S
INTO WRN GA THIS EVENING...SHIFTING EWD WITH TIME INTO PARTS OF THE
CAROLINAS AND SERN VA BY 12Z MONDAY.

..RACY.. 01/07/2007