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   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 240
   NWS STORM PREDICTION CENTER NORMAN OK
   325 PM CDT MON MAY 9 2005
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          CENTRAL TEXAS
   
   EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 325 PM UNTIL 900
   PM CDT.
   
   HAIL TO 4 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
   MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
   
   THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80
   STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTHWEST OF
   WACO TEXAS TO 70 MILES SOUTH SOUTHEAST OF JUNCTION TEXAS.  FOR A
   COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
   UPDATE (WOUS64 KWNS WOU0).
   
   REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
   FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
   PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
   WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
   WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
   TORNADOES.
   
   OTHER WATCH INFORMATION...CONTINUE...WW 239...
   
   DISCUSSION...EXPLOSIVE THUNDERSTORM DEVELOPMENT IS NOW OCCURRING
   OVER TX HILL COUNTRY WITHIN BROAD FIELD OF CUMULUS WHICH DEVELOPED
   DURING THE PAST HOUR OR SO.  AIR MASS IS EXTREMELY UNSTABLE WITH
   SBCAPES IN EXCESS OF 4000 J/KG.  STRONG MIXING AND LIFT ALONG
   OUTFLOW FROM INITIAL STORM MAY BE SUFFICIENT FOR FURTHER RAPID
   THUNDERSTORM DEVELOPMENT OVER CENTRAL TX WHERE CAPPING HAS BEEN
   ERODED.  SHEAR IS MODEST...YET STILL SUFFICIENT...FOR SLOW MOVING
   SUPERCELLS GIVEN THE AMOUNT OF INSTABILITY.  PRIMARY THREAT WILL BE
   FROM VERY LARGE HAIL IN EXCESS OF 2 INCHES IN DIAMETER.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 4 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
   MOTION VECTOR 28015.
   
   
   ...EVANS