[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 201703
SWODY2
SPC AC 201702

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1102 AM CST MON MAR 20 2006

VALID 211200Z - 221200Z

...THERE IS A SLGT RISK OF SVR TSTMS TUE ACROSS THE SOUTHEAST
STATES...MAINLY PARTS OF NRN FL....

MODELS INDICATE THAT HIGH LATITUDE BLOCKING WILL PERSIST THROUGH
THIS FORECAST PERIOD...WITH AN ASSOCIATED CLOSED LOW LINGERING OVER
SOUTHEAST CANADA AND THE NORTHEASTERN STATES...WHILE ANOTHER CLOSED
LOW EVOLVES OVER THE NORTHEAST PACIFIC.  FARTHER SOUTH...A SOUTHERN
BELT OF POLAR WESTERLIES...AND THE SUBTROPICAL WESTERLIES...WILL
COMPRISE A BROAD STRONG...GENERALLY ZONAL FLOW ACROSS THE SOUTHERN
TIER STATES.  WITHIN THIS REGIME...A COUPLE OF EMBEDDED SHORT WAVES
WILL REMAIN OR BECOME MORE PROGRESSIVE.

THE LEAD IMPULSE...WHICH IS NOW ADVANCING INTO/ACROSS THE SOUTH
CENTRAL PLAINS...IS FORECAST TO LIFT INTO THE MIDDLE MISSISSIPPI
VALLEY BY 12Z TUESDAY...BEFORE TURNING SOUTHEASTWARD AND
ACCELERATING THROUGH CONFLUENT FLOW INTO THE WESTERN ATLANTIC BY 12Z
WEDNESDAY.  AN UPSTREAM SHORT WAVE TROUGH WILL BE A BIT SLOWER...BUT
IS STILL PROGGED TO MIGRATE FROM CENTRAL/SOUTHERN CALIFORNIA INTO
THE FOUR CORNERS REGION BY THE END OF THE FORECAST PERIOD.

...SOUTHEAST STATES...
WITH THE BROADER SCALE PATTERN REMAINING SUPPORTIVE OF HIGH SURFACE
PRESSURE ACROSS MUCH OF EASTERN NORTH AMERICA...SURFACE CYCLOGENESIS
ACCOMPANYING SOUTHERN STREAM IMPULSE IS EXPECTED TO REMAIN WEAK.  AN
INITIAL PRIMARY SURFACE LOW LIKELY WILL ALREADY BE WEAKENING OVER
THE TENNESSEE VALLEY BY THE BEGINNING OF THE FORECAST PERIOD...WITH
SECONDARY SURFACE WAVE DEVELOPMENT OCCURRING NEAR/OR SOUTHEAST OF
THE SOUTH CAROLINA COAST.  THIS SHOULD LIMIT EXTENT OF SEVERE THREAT
FOR THIS FORECAST PERIOD.  IN FACT...AS MODERATELY STRONG LOW-LEVEL
WIND FIELDS BECOME WESTERLY RATHER EARLY IN THE DAY...CONVECTIVE
POTENTIAL WILL DIMINISH ACROSS MUCH OF THE SOUTHEAST.

AN EXCEPTION COULD BE MOIST PRE-FRONTAL ENVIRONMENT ACROSS PARTS OF
NORTHERN FLORIDA AND THE FLORIDA PENINSULA...WHERE DEEP LAYER SHEAR 
WILL BE STRONG...AND SURFACE HEATING COULD CONTRIBUTE TO WEAK TO
MODERATE BOUNDARY LAYER DESTABILIZATION.  HOWEVER...LOW-LEVEL
CONVERGENCE WILL BE WEAK/HIGHLY LOCALIZED...AND MID-LEVEL INHIBITION
SUBSTANTIAL...WHICH WILL LIMIT COVERAGE OF STORMS.  A RISK FOR A
TORNADO WILL EXIST IN ANY STORMS WHICH DO DEVELOP...BUT DAMAGING
WIND GUSTS WITH ISOLATED DOWNBURSTS SEEMS LIKELY TO BE PRIMARY
SEVERE THREAT.

...EASTERN GREAT BASIN...
AS A MID-LEVEL JET STREAK NOSES ACROSS THE SOUTHERN PLATEAU
TUESDAY...COOLING/LIFT IN ITS EXIT REGION APPEARS LIKELY TO
CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR CONVECTIVE DEVELOPMENT.
 MUCH OF THIS ACTIVITY IS EXPECTED TO BE DIURNAL...BUT OCCASIONAL
THUNDERSTORMS COULD PERSIST THURSDAY NIGHT NEAR THE FOUR
CORNERS...IN CLOSER PROXIMITY TO MID-LEVEL CIRCULATION.

..KERR.. 03/20/2006