[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 270545
SWODY1
SPC AC 270542

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1142 PM CST SUN NOV 26 2006

VALID 271200Z - 281200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
MID/UPPER LEVEL TROUGH...CURRENTLY DEEPENING ACROSS THE PACIFIC NW
AND INTERMOUNTAIN WEST...IS EXPECTED TO BEGIN TO MOVE EWD THIS
FORECAST PERIOD.  THIS WILL OCCUR AS STRONG MID/UPPER LEVEL WINDS
TRANSLATE INTO THE BASE OF THIS TROUGH FROM THE GREAT BASIN EWD TO
THE CENTRAL PLAINS.  A COUPLE OF SHORT WAVE TROUGHS WITHIN SWLY FLOW
ALOFT WILL TRACK NEWD ACROSS THE CENTRAL STATES THROUGH TONIGHT.

COLD FRONT IS EXPECTED TO EXTEND FROM THE TX PANHANDLE/NW OK NEWD
THROUGH ERN KS TO ERN IA...AND THEN EWD ACROSS SRN WI TO LOWER MI AT
12Z TODAY.  THIS BOUNDARY SHOULD REMAIN MAINLY STATIONARY INTO THE
AFTERNOON...WITH A SURFACE WAVE DEVELOPING OVER WRN OK BY LATE
AFTERNOON AS LEAD SHORT WAVE TROUGH TRACKS ACROSS OK/KS.  THIS
IMPULSE WILL CONTINUE TO MOVE NEWD ACROSS THE MID/LOWER MO VALLEYS
TO THE WRN GREAT LAKES REGION TONIGHT. THE ATTENDANT SURFACE LOW
SHOULD MOVE MORE NWD INTO WRN/NRN IA AS STRONGER HEIGHT FALLS/
SURFACE PRESSURE FALLS DEVELOP ACROSS THE NRN PLAINS AND UPPER
MIDWEST IN RESPONSE TO EWD PROGRESSION OF WRN LONG WAVE TROUGH. 
KS/MO PORTION OF SURFACE FRONT WILL LIKEWISE RETREAT NWD AFTER
28/00Z TO ALONG THE IA/MN BORDER BY 12Z TUESDAY.  MEANWHILE...
PRIMARY CYCLONE IS EXPECTED TO DEEPEN OVER WY TODAY...BEFORE MOVING
EWD INTO SD BY TUESDAY MORNING. 

...SRN PLAINS NEWD TO MID MO VALLEY...
LOW LEVEL MOISTURE WILL CONTINUE TO SPREAD NEWD ALONG/E OF SURFACE
FRONT AS SSWLY LLJ EXTENDING FROM SRN PLAINS TO LOWER MO/MID MS
VALLEYS STRENGTHENS THROUGH THE FORECAST PERIOD...WITH EXTENSIVE
CLOUDINESS LIKELY LIMITING AIR MASS DESTABILIZATION.  

ELEVATED TSTMS MAY BE ONGOING AT 12Z TODAY OVER PARTS OF CENTRAL
KS/NW OK WITHIN REGION OF ISENTROPIC ASCENT NORTH OF COLD FRONT. 
DEEP LAYER ASCENT AND SUBSEQUENT POTENTIAL FOR TSTMS WILL CONTINUE
TO INCREASE INITIALLY ACROSS KS/NW OK...AND THEN SWD THROUGH OK AND
W/NW TX ALONG LEE TROUGH/DRY LINE WITH APPROACH OF LEAD SHORT WAVE
TROUGH.  GENERALLY WEAK INSTABILITY WITH THIS LEAD TROUGH IS
EXPECTED TO LIMIT SEVERE THREAT THROUGH 28/00Z.  AN EXCEPTION MAY
EXIST ACROSS WRN OK/ERN TX PANHANDLE WHERE MLCAPE MAY BE AROUND 500
J/KG BY LATE AFTERNOON...SUPPORTING A THREAT FOR ISOLATED HAIL/
STRONG WINDS.

GREATER SEVERE THREAT...THOUGH STILL ISOLATED IN COVERAGE GIVEN TIME
OF DAY AND SOMEWHAT WEAK INSTABILITY...IS EXPECTED AFTER 28/00Z AS
STEEPER MID LEVEL LAPSE RATES/STRONGER FORCING SPREAD NEWD ACROSS
CENTRAL/SRN PLAINS AHEAD OF STRONGER IMPULSE...NOW LOCATED OVER
CENTRAL CA.  THIS ACTIVITY AND ATTENDANT SEVERE THREAT SHOULD
DEVELOP NEWD AND MAY REACH PARTS OF IA/WRN MO BY 12Z TUESDAY.

..PETERS/TAYLOR.. 11/27/2006