[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 201632
SWODY1
SPC AC 201630

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1030 AM CST MON MAR 20 2006

VALID 201630Z - 211200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF SOUTHERN MS...

...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF THE LOWER MS
VALLEY...CENTRAL GULF COAST REGION...AND PARTS OF SOUTHERN OK...

LARGE UPPER TROUGH CONTINUES TO ROTATE ACROSS THE SOUTHWEST STATES
AND INTO THE SOUTHERN PLAINS TODAY.  MID LEVEL JET MAX OF 100+ KNOTS
IS FORECAST TO NOSE INTO PARTS OF AR/LA THIS EVENING...PROVIDING
STRONG LARGE SCALE ASCENT ACROSS MUCH OF THE LOWER MS VALLEY AND
CENTRAL GULF COAST REGION.  PRESENT INDICATIONS ARE THAT SCATTERED
SEVERE THUNDERSTORMS WILL BE POSSIBLE FROM EAST TX INTO PARTS OF AL
TODAY...AS WELL AS PARTS OF SOUTHERN OK BENEATH COLD UPPER LOW.

...LOWER MS VALLEY...
MORNING SURFACE ANALYSIS SHOWS PRIMARY WARM FRONT EXTENDING FROM
NORTH OF LCH INTO SOUTHERN MS. THIS BOUNDARY IS FORECAST TO LIFT
SLOWLY NORTHWARD TODAY AS UPPER TROUGH APPROACHES FROM THE WEST AND
LOW LEVEL JET INTENSIFIES.  CURRENT VAD/PROFILER DATA ALREADY SHOW
VERY FAVORABLE LOW LEVEL VERTICAL SHEAR PROFILES SOUTH OF FRONT FOR
UPDRAFT ROTATION AND THE THREAT OF TORNADOES.  THREAT SHOULD
INCREASE THIS AFTERNOON AS SMALL POCKETS OF DAYTIME HEATING OCCUR
AND WARM FRONT LIFTS TO NEAR I-20.  SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP ACROSS SOUTHERN LA AND SPREAD EASTWARD ACROSS
SOUTHERN MS.  IF SUFFICIENT INSTABILITY CAN DEVELOP ACROSS SOUTHERN
MS...POTENTIAL WILL EXIST FOR ISOLATED STRONG TORNADOES.  SEVERE
THREAT MAY CONTINUE AFTER DARK INTO PARTS OF AL AND THE WESTERN FL
PANHANDLE.

...SOUTHERN OK INTO WESTERN AR...
VISIBLE SATELLITE IMAGERY SHOWS LINE OF CLEARING SKIES DEVELOPING
NORTHEASTWARD ACROSS NORTH TX INTO SOUTHERN OK.  VERY STEEP LOW/MID
LEVEL LAPSE RATES ARE EXPECTED TO DEVELOP WHERE STRONG HEATING
OCCURS...RESULTING IN MARGINAL/MODERATE INSTABILITY.  ALL MODELS ARE
CONSISTENT IN DEVELOPING ISOLATED THUNDERSTORMS IN THIS REGION. 
COLD TEMPERATURES ALOFT SUGGEST A RISK OF LARGE HAIL IN STRONGER
STORMS.  ACTIVITY SHOULD DIMINISH RAPIDLY AFTER SUNSET.

..HART/TAYLOR.. 03/20/2006