[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 200549
SWODY1
SPC AC 200547

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1147 PM CST TUE DEC 19 2006

VALID 201200Z - 211200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
THOUGH A MID-LEVEL SHORT-WAVE TROUGH IN THE NRN STREAM WILL AFFECT
THE PAC NW AND A SECOND WILL CROSS THE GREAT LAKES/NEW
ENGLAND...MAIN FEATURE WITH RESPECT TO DEEP MOIST CONVECTION WILL BE
THE UPPER LOW MOVING INTO THE CENTRAL CONUS.  THIS
FEATURE...INITIALLY FORECAST OVER NM...IS EXPECTED TO MOVE ENEWD TO
SWRN KS/THE TX AND OK PANHANDLES BY 21/12Z.

AT THE SURFACE...LOW PRESSURE CENTER IS FORECAST TO LINGER OVER THE
WRN KS/WRN OK REGION...WHILE TRAILING FRONT SHIFTS EWD ACROSS TX/OK
THROUGH THE DAY...AND INTO THE LOWER MS VALLEY REGION BY THE END OF
THE PERIOD.  

...SERN TX INTO LA...
SCATTERED SHOWERS AND A FEW THUNDERSTORMS SHOULD BE ONGOING ACROSS
THIS REGION AT THE START OF THE PERIOD...WITHIN WEAK WARM ADVECTION
REGIME.

THOUGH BOUNDARY-LAYER AIRMASS WILL MOISTEN INTO LA AS SURFACE FLOW
VEERS WITH TIME AHEAD OF APPROACHING SURFACE BOUNDARY...WEAK LAPSE
RATES WILL CONTINUE TO LIMIT THE POTENTIAL FOR DESTABILIZATION. 
ADDITIONALLY...STRONGER DEEP-LAYER WIND FIELD IS FORECAST TO REMAIN
NW OF THE WRN GULF COAST REGION...WITH MID-LEVEL JET CORE FORECAST
TO REMAIN ACROSS N TX/OK THROUGH THE PERIOD.

NONETHELESS...STORMS SHOULD BECOME MORE NUMEROUS THROUGH THE SECOND
HALF OF THE PERIOD AS SURFACE BOUNDARY APPROACHES.  LIMITED
INSTABILITY/WEAK LAPSE RATES WILL LIMIT UPDRAFT INTENSITY...AND SO
LITTLE HAIL POTENTIAL AND ONLY A MARGINAL WIND THREAT IS INDICATED. 
ALSO...WITH DEWPOINTS FORECAST IN THE MID 60S ACROSS SERN TX AND
INTO MUCH OF LA AND MODERATE SHEAR EXPECTED IN THE 0-1 KM LAYER...AN
ISOLATED TORNADO CANNOT BE RULED OUT.  HOWEVER...OVERALL SEVERE
POTENTIAL SHOULD REMAIN LOW/BELOW SLIGHT RISK THRESHOLDS THROUGH THE
PERIOD.

..GOSS.. 12/20/2006