MESOSCALE DISCUSSION 0199
   NWS STORM PREDICTION CENTER NORMAN OK
   1053 PM CST THU FEB 21 2013
   
   AREAS AFFECTED...SRN MS
   
   CONCERNING...TORNADO WATCH 38...
   
   VALID 220453Z - 220600Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 38 CONTINUES.
   
   SUMMARY...ENVIRONMENT ACROSS SRN MS /STRONG LOW LEVEL AND DEEP LAYER
   SHEAR AND CONTINUED MOISTENING/ REMAINS CONDUCIVE TO SUPPORT
   SUPERCELLS CAPABLE OF PRODUCING DAMAGING WINDS AND A TORNADO THREAT.
   THESE THREATS ARE EXPECTED TO PERSIST BEYOND 05Z...RESULTING IN A
   LOCAL WFO TEMPORAL EXTENSION OF WW 38.
   
   DISCUSSION...SURFACE STREAMLINE ANALYSES DURING THE LATE EVENING
   INDICATED A CORRIDOR OF LOW LEVEL CONVERGENCE EXTENDING FROM SOUTH
   CENTRAL LA INTO SRN AND EAST CENTRAL MS. ALTHOUGH LOW LEVEL WINDS
   WILL CONTINUE TO VEER AND EVENTUALLY WEAKEN OVERNIGHT INTO EARLY FRI
   MORNING...A TEMPORAL WINDOW EXISTS IN THE SHORT TERM FOR A CONTINUED
   SEVERE WEATHER THREAT BEYOND 05Z...SUCH THAT PARTS OF WW 38 WILL BE
   EXTENDED FOR ANOTHER 1-2 HOURS. TRENDS IN SURFACE OBSERVATIONS
   ACROSS THE WARM SECTOR HAVE INDICATED MOISTURE RETURN OF GULF/
   MODIFIED CP AIR PERSISTS ACROSS SERN LA INTO SOUTH CENTRAL MS. THE
   WARM FRONT DELINEATING THE NRN EXTENT OF THIS RICHER MOISTURE
   EXTENDED SEWD FROM S OF KJAN TO SERN MS /INVOF KGPT/. EFFECTIVE SRH
   /THOUGH WEAKER FROM EARLIER THIS EVENING/ RANGES FROM 200-300 M2/S2
   AND THUS IS CONDUCIVE FOR LOW LEVEL STORM ROTATION/TORNADO THREAT...
   WITH RADAR IMAGERY INDICATING THIS SCENARIO BEING REALIZED IN
   VICINITY AND JUST S OF THE WARM FRONT. 
   
   UNTIL THE LOW LEVEL SHEAR UNDERGOES FURTHER WEAKENING...THE THREAT
   FOR A TORNADO OR TWO AND DAMAGING WINDS WILL REMAIN POSSIBLE INTO
   THE EARLY OVERNIGHT HOURS.
   
   ..PETERS.. 02/22/2013
   
   
   ATTN...WFO...MOB...JAN...LIX...
   
   LAT...LON   31009109 32008987 32218936 31818926 31818896 31448896
               31348913 30918919 30908964 30909091 31009109