[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 120614
SWODY2
SPC AC 120613

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1213 AM CST FRI JAN 12 2007

VALID 131200Z - 141200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...

POSITIVELY TILTED UPPER TROUGH WILL CONTINUE TO DROP SLOWLY SWD AND
INTO THE SWRN U.S. SATURDAY. DOWNSTREAM FROM THIS FEATURE...A BROAD
LOW AMPLITUDE UPPER RIDGE WILL EXIST FROM THE MS VALLEY EWD THROUGH
PARTS OF THE OH VALLEY AND SERN STATES. AT THE SURFACE A COLD ARCTIC
FRONT WILL CONTINUE SWD. BY 12Z SATURDAY THIS BOUNDARY SHOULD EXTEND
FROM THE NERN U.S. SWWD INTO THE LOWER MS VALLEY THROUGH CNTRL AND
WRN TX. THIS SHALLOW WEDGE OF COLD AIR SHOULD CONTINUE SLOWLY SWD
THROUGH TX DURING THE DAY.


...SWRN THROUGH S CNTRL AND ERN TX...

PARTIALLY MODIFIED GULF AIR WITH BOUNDARY LAYER DEWPOINTS MAINLY IN
THE LOW TO MID 60S WILL HAVE ADVECTED NWD INTO THE PRE-FRONTAL WARM
SECTOR OF SRN AND S CNTRL TX INTO THE LOWER MS VALLEY. SOMEWHAT
STRONGER MID LEVEL LAPSE RATES AROUND 6.5 C/KM INITIALLY OVER SWRN
TX MAY ADVECT INTO PARTS OF S CNTRL TX ABOVE THE RETURNING LOW LEVEL
MOISTURE. THIS ALONG WITH POTENTIAL FOR PRE-FRONTAL SURFACE HEATING
SHOULD CONTRIBUTE TO SOME DESTABILIZATION DURING THE DAY WITH MUCAPE
FROM 400 TO 800 J/KG NEAR AND JUST S OF THE FRONT.

MODELS SUGGEST CONVECTION MAY ALREADY BE IN PROGRESS FROM PARTS OF
NERN TX...ERN OK INTO THE LOWER MS VALLEY. HOWEVER...THIS ACTIVITY
WILL BE ELEVATED IN POST FRONTAL ZONE WHERE CAPE WILL BE LIMITED.
OTHER STORMS MAY DEVELOP DURING THE AFTERNOON IN VICINITY OF THE
FRONT AS THE ATMOSPHERE DESTABILIZES. HOWEVER...ORIENTATION OF THE
MEAN DEEP LAYER FLOW WITH RESECT THE FRONT SUGGEST STORMS WILL LIFT
NEWD OVER THE COOL FRONTAL SURFACE AND BECOME ELEVATED...ESPECIALLY
OVER S CNTRL THROUGH SWRN TX. STORMS MAY INCREASE OVERNIGHT NEAR AND
N OF THE FRONT AS THE SLY LOW LEVEL JET AND FORCING FOR ASCENT
STRENGTHENS DOWNSTREAM FROM ADVANCING UPPER TROUGH. VERTICAL SHEAR
FOR STORMS DEVELOPING NEAR THE FRONT WILL BE SUFFICIENT FOR
SUPERCELLS. HOWEVER...TENDENCY WILL REMAIN FOR STORMS TO LIFT NEWD
AND BECOME ELEVATED. INSTABILITY AND MID LEVEL LAPSE RATES MAY
BECOME SUFFICIENT FOR A THREAT OF MARGINALLY SEVERE HAIL.

FARTHER EAST ACROSS PARTS OF ERN TX...A MORE NE ORIENTATION OF THE
FRONT SUGGESTS ANY STORMS DEVELOPING ALONG OR S OF THIS PART OF THE
BOUNDARY MAY HAVE A BETTER CHANCE OF REMAINING SURFACE BASED.
HOWEVER...MODEST LAPSE RATES/INSTABILITY AND WEAKER FORCING FOR DEEP
LAYER ASCENT IN THIS REGION SHOULD SERVE AS LIMITING FACTORS.

..DIAL.. 01/12/2007