DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 081236
SWODY1
SPC AC 081234

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0634 AM CST SAT DEC 08 2012

VALID 081300Z - 091200Z

...NO SVR TSTM AREAS FORECAST...

...ERN TX/OK TO KY/TN THROUGH TONIGHT...
WITHIN A BROAD CYCLONIC FLOW REGIME OVER THE CONUS...ONE SHORTWAVE
TROUGH WILL EJECT ENEWD FROM THE GREAT LAKES TO NEW ENGLAND...AS AN
UPSTREAM TROUGH AMPLIFIES OVER THE NRN/CENTRAL ROCKIES. AT THE
SURFACE...A QUASI-STATIONARY FRONT FROM CENTRAL TX TO THE LOWER OH
VALLEY THIS MORNING WILL DRIFT A LITTLE TO THE N IN RESPONSE TO
PRESSURE FALLS ACROSS THE CENTRAL PLAINS. THIS FRONT WILL PROVIDE
THE PRIMARY FOCUS FOR THUNDERSTORM DEVELOPMENT THROUGH TONIGHT.

S OF THE SLOW-MOVING FRONT...BOUNDARY LAYER DEWPOINTS RANGE FROM THE
UPPER 50S ACROSS TN/KY TO THE MID-UPPER 60S ALONG THE TX COAST.
DAYTIME HEATING IN CLOUD BREAKS /MOST PROBABLE FROM E CENTRAL TX
INTO NW LA/ AND MIDLEVEL LAPSE RATES OF 6.5-7 C/KM WILL CONTRIBUTE
TO MLCAPE OF 750-1250 J/KG ALONG THE FRONT THIS AFTERNOON. THOUGH
FORCING FOR ASCENT WILL BE WEAK...A FEW THUNDERSTORMS MAY DEVELOP
ALONG THE BOUNDARY AS CONVECTIVE INHIBITION WEAKENS BY MID-LATE
AFTERNOON. THE DEGREE OF BUOYANCY WILL BE SUFFICIENT FOR A
LOW-PROBABILITY RISK FOR ORGANIZED STORMS WITH STRONG GUSTS AND
MARGINALLY SEVERE HAIL...GIVEN 30-40 KT EFFECTIVE BULK SHEAR.
OVERNIGHT...THE THREAT FOR ELEVATED THUNDERSTORMS WILL INCREASE
ACROSS ERN OK AND AR IN A STRENGTHENING WAA REGIME. ELEVATED
INSTABILITY AND SUFFICIENT CLOUD LAYER VERTICAL SHEAR MAY SUPPORT A
FEW STORMS CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL.

..THOMPSON/ROGERS.. 12/08/2012

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.