MESOSCALE DISCUSSION 0487
   NWS STORM PREDICTION CENTER NORMAN OK
   0134 AM CDT SAT APR 14 2007
   
   AREAS AFFECTED...SE TX...LA...WRN MS
   
   CONCERNING...TORNADO WATCH 136...138...
   
   VALID 140634Z - 140730Z
   
   A SEVERE WEATHER THREAT IS DEVELOPING EASTWARD INTO THE LOWER
   MISSISSIPPI VALLEY TONIGHT.  
   
   INTENSIFICATION OF PRE-FRONTAL CONVECTIVE BAND IS ONGOING TO THE
   SOUTH/SOUTHWEST OF FRONTAL WAVE...EAST/SOUTHEAST OF SHREVEPORT LA
   INTO THE HOUSTON VICINITY.  THIS IS APPARENTLY OCCURRING IN RESPONSE
   TO STRENGTHENING LOW-LEVEL LIFT IN NARROW MOIST TONGUE CHARACTERIZED
   BY LOWER 70S DEW POINTS.  HIGH MOISTURE CONTENT IS CONTRIBUTING TO
   MOST UNSTABLE CAPE OF 1000-2000 J/KG...SUPPORTIVE OF VIGOROUS
   UPDRAFTS ACCOMPANIED BY HEAVY RAIN AND HAIL.  AS A SQUALL LINE
   CONTINUES TO EVOLVE IN A STRONGLY SHEARED...LARGELY
   UNIDIRECTIONAL...40-50 KT MEAN SOUTHWESTERLY FLOW REGIME...SEVERE
   THREAT SEEMS LIKELY TO INCREASE THROUGH 09-12Z ACROSS CENTRAL/
   NORTHEAST LOUISIANA INTO WEST CENTRAL MISSISSIPPI.  BOWING SEGMENTS
   MAY EVENTUALLY EVOLVE ASSOCIATED WITH DOWNBURSTS AND DAMAGING WIND
   GUSTS.  AND...DESPITE WEAK LOW-LEVEL LAPSE RATES...NEAR SATURATED
   PROFILES AND LARGE CLOCKWISE CURVED HODOGRAPHS IN THE LOWEST
   KILOMETER OR SO MAY BE SUPPORTIVE OF EMBEDDED SUPERCELLS WITH
   TORNADOES.
   
   ..KERR.. 04/14/2007
   
   
   ATTN...WFO...JAN...LIX...LCH...SHV...
   
   31339325 32089264 32749180 33529084 33528984 32548966
   31669036 30929118 30449208 30469295 30699324