[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 090600
SWODY1
SPC AC 090559

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1159 PM CST WED MAR 08 2006

VALID 091200Z - 101200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF LA...SRN
AR...MS..WRN TN...WRN KY AND NWRN AL...

...THERE IS A SLGT RISK OF SVR TSTMS THAT SURROUNDS THE MODERATE
RISK FROM ERN TX NEWD ACROSS THE LOWER/MID MS AND OH VALLEYS...SWD
INTO AL AND GA...

SIGNIFICANT SEVERE WEATHER EVENT POSSIBLE TODAY AND THIS EVENING
...ESPECIALLY ACROSS THE LOWER MS AND TN VALLEYS...

...SYNOPSIS...
INTENSE SHORTWAVE TROUGH IS FORECAST TO BE EJECTED FROM WRN TX NEWD
INTO THE TN VALLEY LATE THIS AFTERNOON AND INTO THE OHIO VALLEY
TONIGHT...AS A 100-110 KT MID LEVEL JET MAX ROUNDS THE BASE OF THE
TROUGH...RESULTING IN THE SYSTEM TO BECOME STRONGLY NEGATIVELY
TILTED.

...LOWER AND MID MS/TN VALLEY REGION...
NUMEROUS STORMS ACROSS TX/OK WILL SPREAD RAPIDLY NEWD INTO AR/MO/ERN
OK BY MORNING. FAVORABLE STRONG LARGE SCALE ASCENT/DEEP LAYER SHEAR
AND INSTABILITY SHOULD SUPPORT ONGOING SEVERE THREAT THROUGH THE
MORNING AS THE STORMS DEVELOP/SHIFT NEWD THROUGH THE DAY INTO THE
MID MS VALLEY.

STRONGER CONVECTION MAY BE ONGOING DURING THE MORNING ACROSS
PORTIONS OF ERN TX AS MID LEVEL SPEED MAX AND STRONG THERMAL TROUGH
PUNCH RAPIDLY EWD ACROSS A MODERATELY UNSTABLE AIR MASS. THE
COMBINATION OF DIURNAL HEATING...RESULTING IN STRENGTHENING
INSTABILITY...PLUS THE UPPER TROUGH BEGINNING TO LIFT NEGATIVELY
TILTED INTO THE LOWER MS RIVER VALLEY SHOULD RESULT IN STORMS TO
INTENSIFY ACROSS LA BY MIDDAY AND THEN SPREAD RAPIDLY NEWD ACROSS
MS/AR/AL/TN/SERN MO/WRN KY DURING THE AFTERNOON. THE BACKING WINDS
ALOFT AND PRONOUNCED THERMAL TROUGH...ESPECIALLY FROM AR/NRN MS NEWD
SUGGESTS THAT THE STORMS IN THIS AREA SHOULD EVOLVE INTO A FAST
MOVING LINE. THE EXTREMELY STRONG ENVIRONMENTAL WINDS...70 KT AT 850
MB AND 110 KT AT 500 MB...AND THE STRONG SUBSIDENCE BEHIND THE
TROUGH MAY RESULT IN SIGNIFICANT WIND DAMAGE.

AS THE SRN END OF THE TROUGH LIFTS NEWD FROM LA NEWD ACROSS MS AND
INTO NWRN AL...MORE CELLULAR STORMS ARE POSSIBLE. IF THE STORMS CAN
REMAIN SOMEWHAT ISOLATED...INTENSE LOW/DEEP LEVEL SHEAR WOULD
SUPPORT TORNADOES...SOME WHICH MAY BE QUITE STRONG. THE TORNADO
POTENTIAL WILL BE THE GREATEST FROM SERN AR/LA NEWD ACROSS MUCH OF
MS AND NWRN AL BETWEEN 18Z AND 02Z.

AS THE MAIN TROUGH LIFTS NEWD INTO THE OH VALLEY TONIGHT...THE
STRONGER FORCING WILL BECOME MORE REMOVED FROM THE STRONGER
INSTABILITY. STORMS WITH MAINLY A WIND THREAT WILL SPREAD EWD INTO
INTO ERN KY SWD INTO WRN GA...THOUGH THE SEVERE THREAT SHOULD
GRADUALLY DIMINISH THROUGH THE NIGHTTIME HOURS.

..IMY.. 03/09/2006