MESOSCALE DISCUSSION 0522
   NWS STORM PREDICTION CENTER NORMAN OK
   1248 PM CDT THU APR 18 2013
   
   AREAS AFFECTED...PORTIONS OF ERN AR...NE LA...SE MO...SRN IL...SW
   IND...WRN KY...WRN TN...NW MS
   
   CONCERNING...TORNADO WATCH 125...
   
   VALID 181748Z - 181915Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 125 CONTINUES.
   
   SUMMARY...THUNDERSTORMS ARE EXPECTED TO INTENSIFY ACROSS PARTS OF
   ERN AR INTO WRN TN...NW MS AND NE LA. STRONG WINDS WILL BE THE MAIN
   THREAT...BUT A FEW TORNADOES ARE STILL POSSIBLE. ACROSS NORTHERN
   PORTIONS OF THE WATCH AREA...INTENSIFICATION MAY BE SLOWER/LESS
   INTENSE.
   
   DISCUSSION...REGIONAL RADAR LOOP THE LAST 30-60 MINUTES INDICATES
   THAT SOME STORM INTENSIFICATION MAY BE UNDERWAY. THE AIRMASS AHEAD
   OF THE EWD ADVANCING LINE OF CONVECTION IS CHARACTERIZED BY MAINLY
   LOW TO MID 60S DEWPOINTS...EXCEPT ACROSS SE AR INTO PARTS OF SE LA
   AND NW MS WHERE DEWPOINTS APPROACHING 70 DEGREES F WERE NOTED ON 17Z
   SFC ANALYSIS. THE COMBINATION OF SLIGHTLY HIGHER DEWPOINTS, BACKED
   SFC WINDS AND GREATER POTENTIAL FOR CONTINUED SFC WARMING UNDER
   BROKEN CLOUDINESS MAY BE THE BEST CHANCE FOR FURTHER INTENSIFICATION
   FOR AREAS SOUTH OF THE MEMPHIS AREA AND WEST OF I-55 IN MS/SE
   AR...AND NORTH OF I-20. 17Z MESOANALYSIS INDICATED AN UNCAPPED
   ENVIRONMENT WITH SBCAPE APPROACHING 1500-2000 J/KG IN THIS REGION.
   AS SUCH...A NEW WATCH MAY BE NEEDED LATER THIS AFTERNOON DOWNSTREAM
   OF WW125. FAVORABLE HODOGRAPHS AS SEEN IN 12Z AND 18Z RAOBS IN
   ADDITION TO WSR-88D VWP PROFILES CONTINUE TO INDICATE POTENTIAL FOR
   TORNADOES IN ADDITION TO STRONG/DAMAGING WINDS.
   
   ACROSS NORTHERN PORTIONS OF THE WATCH...INTENSIFICATION IS LESS
   CERTAIN. THIS IS DUE IN PART TO LOWER DEWPOINTS AND SLIGHTLY VEERED
   SFC WINDS. STRONG DEEP LAYER FLOW AND FORCING FOR ASCENT WILL
   CONTINUE TO BE FOCUS ACROSS THE AREA THROUGH THE AFTERNOON...WHICH
   COULD HELP COMPENSATE FOR WEAKER INSTABILITY.
   
   ..LEITMAN/KERR.. 04/18/2013
   
   
   ATTN...WFO...LMK...OHX...IND...PAH...MEG...JAN...LSX...LZK...
   SGF...SHV...
   
   LAT...LON   38548914 38528652 35958840 33598980 32479084 32219248
               32379369 33559324 36659109 38548914