DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 030045
SWODY1
SPC AC 030042

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0642 PM CST FRI JAN 02 2009

VALID 030100Z - 031200Z

...NO SVR TSTM AREAS FORECAST...

...S CNTRL THROUGH SE TX...

WV IMAGERY SHOWS A VORTICITY MAXIMA OVER NRN MEXICO...AND THIS
FEATURE WILL CONTINUE EAST INTO SRN AND CNTRL TX LATER TONIGHT.
RICHER LOW LEVEL MOISTURE HAS SPREAD INLAND WITH DEWPOINTS IN THE
LOW-MID 60S ALONG THE TX COASTAL PLAIN. INCREASING SSWLY BOUNDARY
LAYER FLOW DOWNSTREAM FROM THE SHORTWAVE TROUGH WILL MAINTAIN AN
INFLUX OF PARTIALLY MODIFIED GULF AIR IN THIS REGION. THIS MOISTURE
HAS RETURNED NWD BENEATH A PLUME OF STEEPER 7-7.5 MID-LEVEL LAPSE
RATES. THESE PROCESSES HAVE CONTRIBUTED TO DESTABILIZATION WITH
OBSERVED SOUNDINGS INDICATING MUCAPE AROUND 1000 J/KG. THE 00Z AND
FORECAST SOUNDING DATA SHOW THE BOUNDARY LAYER REMAINS CAPPED
BENEATH AN INVERSION PRESENT BETWEEN 850 AND 700 MB.

OBSERVED RAOB DATA SHOW WARMER 850 MB TEMPERATURES UPSTREAM OF THE
TX COASTAL PLAIN AND THIS WARMER AIR MAY ADVECT EWD...MAINTAINING A
CAP TO SURFACE BASED STORMS OVERNIGHT. HOWEVER...INCREASING FORCING
FOR ASCENT ATTENDING THE SHORTWAVE TROUGH SHOULD EVENTUALLY PROMOTE
THUNDERSTORM DEVELOPMENT LATER TONIGHT INITIALLY FROM S OR S CNTRL
TX...EXPANDING NE THROUGH THE END OF THE PERIOD. TIME OF DAY WILL
MAINTAIN A STABLE BOUNDARY LAYER BENEATH THE INVERSION SUGGESTING
STORMS THAT DEVELOP MAY REMAIN ELEVATED. EFFECTIVE BULK SHEAR WILL
INCREASE TO 40+ KT WITH THE APPROACHING MID LEVEL JET AND BECOME
SUFFICIENT FOR ORGANIZED MULTICELLS AND UPDRAFT ROTATION. THE
STEEPENING MID LEVEL LAPSE RATES AND POTENTIAL FOR UPDRAFT ROTATION
WILL PROMOTE A THREAT FOR HAIL. THE STRONGER STORMS MAY ALSO PRODUCE
GUSTY WINDS. OVERALL SEVERE THREAT DOES NOT APPEAR TO WARRANT MORE
THAN 5% SEVERE PROBABILITIES AT THIS TIME. A BETTER CHANCE FOR
SEVERE STORMS WILL DEVELOP SATURDAY FROM SE TX INTO THE LOWER MS
VALLEY.

..DIAL.. 01/03/2009

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.