MESOSCALE DISCUSSION 2413
   NWS STORM PREDICTION CENTER NORMAN OK
   0155 PM CST SAT NOV 20 2004
   
   AREAS AFFECTED...CENTRAL TX
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 201955Z - 202200Z
   
   ISOLATED SEVERE HAIL STORMS ARE EXPECTED OVER THE NEXT SEVERAL
   HOURS. 
   
   ELEVATED STORMS HAVE FORMED N OF SURFACE BOUNDARY WHERE WEAK SLY
   FLOW ABOVE MORE STABLE SURFACE AIR IS MAINTAINING FEED OF MARGINAL
   INSTABILITY.  ENVIRONMENT WILL REMAIN FAVORABLE FOR CONTINUED
   DEVELOPMENT AS SRN EDGE OF LEAD VORT MAX OVERSPREADS THE AREA.
   
   SURFACE ANALYSIS SHOWS TEMPERATURES HAVE WARMED INTO THE LOWER 70S
   OVER MUCH OF NERN TX WITH DEWPOINTS NEAR 60.  MODIFIED SOUNDINGS
   YIELD SUFFICIENT INSTABILITY FOR HAIL PRODUCTION. JUXTAPOSITION OF
   FAVORABLE SELY LOW LEVEL FLOW AND 50 KT SWLY MID LEVEL FLOW IS
   FAVORABLE FOR LONG-LIVED CONVECTION PRODUCING LARGE HAIL.
   
   ..JEWELL.. 11/20/2004
   
   
   ATTN...WFO...FWD...EWX...SJT...
   
   30569840 30279974 30350067 30980122 31640092 32469968
   32959819 32689680 31789649