MESOSCALE DISCUSSION 0205
   NWS STORM PREDICTION CENTER NORMAN OK
   1254 PM CST TUE MAR 08 2011
   
   AREAS AFFECTED...LA...SRN AR...AND PARTS OF CENTRAL/SWRN MS
   
   CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 
   
   VALID 081854Z - 081930Z
   
   TORNADO WATCH WILL BE COORDINATED SOON FOR PARTS OF SRN LA INTO SWRN
   MS...GIVEN SUBSTANTIAL WEAKENING OF THE CAP PER THE SPECIAL 18Z LCH
   SOUNDING AND STRONG LOW LEVEL AND DEEP LAYER SHEAR WITHIN
   DESTABILIZING AIR MASS.  A SEVERE TSTM WATCH IS POSSIBLE FARTHER N
   ACROSS PARTS OF NRN LA/SRN AR INTO CENTRAL MS FOR PRIMARILY A HAIL
   THREAT THIS AFTERNOON.  
   
   TSTM COVERAGE SHOULD GRADUALLY INCREASE ACROSS NRN LA/SRN AR INTO
   CENTRAL AND SWRN MS THIS AFTERNOON...WHILE ADDITIONAL STORMS DEVELOP
   OVER SRN LA.  INITIAL THREAT WILL BE HAIL GIVEN ELEVATED TSTMS WITH
   MUCH OF THIS EARLY-MID AFTERNOON ACTIVITY.  HOWEVER... STORMS
   DEVELOPING OVER SRN LA ARE LOCATED INVOF THE NWD MOVING WARM
   FRONT...AND ARE LIKELY SURFACE BASED OR NEARLY SO.
   
   LATE MORNING/EARLY AFTERNOON SURFACE ANALYSES SHOWED THE WARM FRONT
   HAD MOVED A LITTLE FARTHER INLAND ACROSS THE SRN EXTENT OF LA AND
   EXTENDED NWWD THROUGH E TX TO AN AREA OF LOW PRESSURE OVER NORTH
   CENTRAL TX.  SURFACE DEWPOINT TEMPERATURES IN THE UPPER 60S WERE
   LOCATED AS FAR INLAND AS LCH-LFT AND WWD INTO SE TX...WHILE MID 60S
   VALUES EXTENDED FROM POE TO BTR.  REGIONAL RADAR IMAGERY SHOWED
   TSTMS LOCATED E/SE OF LFT AND W OF BTR...WITH THIS ACTIVITY
   DEVELOPING ALONG THE ERN EXTENT OF GREATER CLOUD COVER WHERE SURFACE
   HEATING IS STRONGER...AIDING IN BOOSTING INSTABILITY /MUCAPE
   1000-1500 J PER KG/.  THERMODYNAMICS AND INCREASING EFFECTIVE BULK
   SHEAR /40-50 KT/ WILL SUPPORT ORGANIZED STORMS WITH THREATS FOR HAIL
   AND DAMAGING WINDS.  ANY STORM FORMING NEAR THE WARM FRONT WILL HAVE
   A GREATER POTENTIAL TO PRODUCE A TORNADO...GIVEN LOW LEVEL HODOGRAPH
   CURVATURE PER 18Z LCH VAD.
   
   FARTHER N...STORMS DEVELOPING OVER NRN LA AND ACROSS AR INTO SWRN TO
   CENTRAL MS WILL LIKELY REMAIN ELEVATED THROUGH THE AFTERNOON GIVEN
   DISTANCE FROM WARM SECTOR.  FAVORABLE THERMODYNAMICS /STEEP MIDLEVEL
   LAPSE RATES ATOP RETURNING LOW LEVEL MOISTURE/ AND INCREASING
   EFFECTIVE BULK SHEAR AS STRONGER MIDLEVEL WINDS SPREAD EWD WITH
   APPROACHING SRN PLAINS TROUGH WILL SUPPORT STORM ORGANIZATION.  HAIL
   WILL BE THE PRIMARY THREAT...SOME SEVERE...WITH THE STRONGER/
   LONG-LIVED CELLS.
   
   ..PETERS.. 03/08/2011
   
   
   ATTN...WFO...JAN...LIX...LZK...LCH...SHV...
   
   LAT...LON   30019168 30199270 30719350 31879398 33339376 34029168
               33369008 32908911 31358930 30159003 29769030 30019168