SEL9
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 219
   NWS STORM PREDICTION CENTER NORMAN OK
   930 AM CDT THU APR 20 2006
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          CENTRAL TEXAS
   
   EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 930 AM UNTIL
   400 PM CDT.
   
   HAIL TO 2.5 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 70 MILES SOUTH
   SOUTHEAST OF DEL RIO TEXAS TO 55 MILES NORTHEAST OF SAN ANGELO
   TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
   WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).
   
   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 218...
   
   DISCUSSION...SLY LLJ WILL CONTINUE TO FEED STRONG TO SEVERE
   THUNDERSTORMS OVER THE HILL COUNTRY AND EDWARDS PLATEAU REGION
   TODAY. VERY STEEP LAPSE RATES...MODERATE INSTABILITY AND EFFECTIVE
   SHEAR FROM 35-45 KT WILL REMAIN SUFFICIENT FOR SUPERCELL STRUCTURES.
    THIS WILL ENHANCE THE POTENTIAL FOR LARGE HAIL.  ISOLATED DAMAGING
   WINDS AND LOW LEVEL ROTATION MAY BECOME MORE PREVALENT THROUGH THE
   AFTERNOON AS HEATING DESTABILIZES THE BOUNDARY LAYER.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
   MOTION VECTOR 21015.
   
   
   ...EVANS