[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 121633
SWODY1
SPC AC 121631

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1031 AM CST FRI JAN 12 2007

VALID 121630Z - 131200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
LARGE DEVELOPING CLOSED LOW OVER NV/CA WILL MOVE SLOWLY EWD OVER THE
SRN GREAT BASIN THROUGH EARLY SATURDAY...WITH A BROAD SWATH OF SW
FLOW ALOFT DOWNSTREAM OVER THE CENTRAL AND ERN CONUS.  IN THE
LOW-LEVELS...A SHARP ARCTIC FRONT IS MOVING SLOWLY SEWD ACROSS THE
SRN PLAINS AND MID MS VALLEY.  PRONOUNCED WAA ABOVE THE FRONTAL
SURFACE IS SUPPORTING AN INCREASING AREA OF PRECIPITATION NEAR AND N
OF THE FRONT FROM NW TX INTO CENTRAL OK...AND THIS PRECIPITATION
SHOULD INCREASE IN COVERAGE WHILE SPREADING NEWD TO THE OH VALLEY
LATER TODAY THROUGH TONIGHT.  MUCH OF THE PRECIPITATION WILL BE
FREEZING RAIN A COUPLE OF COUNTIES N OF THE SURFACE FRONT...WHERE
WEAK MID LEVEL INSTABILITY COULD SUPPORT A FEW EMBEDDED ELEVATED
THUNDERSTORMS.

FARTHER S...BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 60S WILL BE
MAINTAINED ALONG THE FRONT FROM NE INTO CENTRAL TX...WHILE DEWPOINTS
SHOULD REACH THE UPPER 60S ACROSS THE LOWER TX COAST.  REGIONAL 12Z
SOUNDINGS SHOW THE POTENTIAL FOR WEAK SURFACE-BASED INSTABILITY NEAR
THE FRONT...ALONG WITH DEEP LAYER VERTICAL SHEAR THAT WILL BE
SUFFICIENT FOR ORGANIZED SEVERE STORMS.  HOWEVER...THE FLOW REGIME
IS LARGELY ANAFRONTAL WHERE CONVECTION THAT FORMS ALONG THE FRONT
WILL MOVE OVER THE SHALLOW COLD AIR MASS...LIMITING ANY WIND
DAMAGE/TORNADO THREAT.  SOMEWHAT STEEPER MID LEVEL LAPSE RATES OVER
W TX COULD ALLOW FOR SOME SMALL HAIL WITH THE STRONGER
CONVECTION...THOUGH STORM COVERAGE IS IN QUESTION THIS FAR SW.

..THOMPSON.. 01/12/2007