MESOSCALE DISCUSSION 0846
   NWS STORM PREDICTION CENTER NORMAN OK
   0652 PM CDT FRI MAY 09 2008
   
   AREAS AFFECTED...SOUTH CENTRAL TX
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 289...
   
   VALID 092352Z - 100045Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 289
   CONTINUES.
   
   TSTMS DEVELOPING OVER SOUTH CENTRAL TX WILL POSE A THREAT FOR
   DAMAGING WINDS AND HAIL THIS EVENING.
   
   STRONG SURFACE HEATING /TEMPERATURES IN THE MID-UPPER 90S/ COMBINED
   WITH CONVERGENCE ALONG A PRE-FRONTAL SURFACE TROUGH OVER SOUTH
   CENTRAL TX HAS RESULTED IN A COUPLE OF TSTMS DEVELOPING SINCE 2230Z
   OVER GILLESPIE/LLANO COUNTIES.  THE AIR MASS ACROSS THIS REGION
   WHERE SURFACE DEWPOINTS ARE IN THE 60S BENEATH 7-7.5 C/KM MID LEVEL
   LAPSE RATES IS MODERATELY TO VERY UNSTABLE.  THIS COMBINED WITH
   EFFECTIVE BULK SHEAR OF 50-60 KT IS VERY FAVORABLE FOR SUPERCELLS. 
   HOWEVER...OVERALL COVERAGE SHOULD REMAIN RATHER ISOLATED GIVEN THE
   LACK OF STRONGER AND MORE DISCERNABLE UPPER FORCING.  CURRENT
   THINKING SUGGESTS THAT THE ONGOING STORMS SHOULD INCREASE IN
   INTENSITY AS THEY TRACK EWD INTO THE MORE UNSTABLE AIR MASS.  THIS
   ACTIVITY IS EXPECTED TO REMAIN DIURNALLY-DRIVEN WITH A WEAKENING
   TREND IN STORM INTENSITY TOWARD 03Z AS THE LOSS OF DAY TIME HEATING
   STABILIZES THE BOUNDARY LAYER.
   
   ..PETERS.. 05/09/2008
   
   
   ATTN...WFO...HGX...FWD...CRP...EWX...SJT...
   
   29110012 29630048 30080024 30609960 30919863 30989789
   30749726 30359669 29819663 29239666 28959704 28659784
   28669816 29129849