MESOSCALE DISCUSSION 0647
   NWS STORM PREDICTION CENTER NORMAN OK
   0937 AM CDT TUE MAY 11 2004
   
   AREAS AFFECTED...S THROUGH SE TX
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 111437Z - 111630Z
   
   PORTIONS OF S THROUGH SE TX WILL BE UPGRADED TO A SLIGHT RISK ON THE
   1630 UPDATE FOR THREAT OF ISOLATED TORNADOES TODAY.
   
   THIS MORNING A VERY MOIST BOUNDARY LAYER EXISTS OVER S AND SE TX
   WITH DEWPOINTS IN THE LOW TO MID 70S AND MODERATELY STEEP MID LEVEL
   LAPSE RATES. LATEST VISIBLE IMAGERY SHOWS ENOUGH BREAKS IN THE
   CLOUDS TO SUPPORT SOME SURFACE HEATING INTO THE AFTERNOON WITH
   MLCAPE FROM 2500 TO 3000 J/KG. VWP DATA SHOW 0-1 KM SHEAR FROM 30 TO
   35 KT...AND WITH SRN BRANCH SHORTWAVE LIFTING NEWD THROUGH CNTRL TX
   AND LEE CYCLOGENESIS OVER THE HIGH PLAINS...AT LEAST MODERATELY
   STRONG LOW LEVEL FLOW AND SHEAR WILL LIKELY PERSIST INTO THE
   AFTERNOON. MID LEVEL FLOW IS RELATIVELY WEAK. HOWEVER...LOW LCL
   HEIGHTS...STRONG CAPE AND LOW LEVEL SHEAR APPEAR SUPPORTIVE OF
   ISOLATED TORNADOES AS STORMS CONTINUE TO DEVELOP AND INTENSIFY LATE
   THIS MORNING INTO THE AFTERNOON.
   
   ..DIAL.. 05/11/2004
   
   
   ATTN...WFO...HGX...CRP...EWX...BRO...
   
   26559746 26549799 27949835 29529737 30449530 29729444
   29069528 28519653 27749736