SEL3
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 693
   NWS STORM PREDICTION CENTER NORMAN OK
   200 AM MDT TUE AUG 3 2004
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          WESTERN AND CENTRAL SOUTH DAKOTA
   
   EFFECTIVE THIS TUESDAY MORNING FROM 200 AM UNTIL 700 AM MDT.
   
   HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
   MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
   
   THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 45 STATUTE MILES
   NORTH AND SOUTH OF A LINE FROM 80 MILES NORTHWEST OF PHILIP SOUTH
   DAKOTA TO 25 MILES NORTH NORTHEAST OF CHAMBERLAIN SOUTH DAKOTA.
   
   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.
   
   DISCUSSION...MCS WITH AN EMBEDDED BOW ECHO OVER NW SD WILL MOVE
   ESEWD ALONG THE INSTABILITY AXIS TOWARD CENTRAL SD...WITH A
   CONTINUED THREAT FOR DAMAGING WINDS.  ADDITIONALLY...VERTICAL SHEAR
   AND INSTABILITY WILL BE SUFFICIENT FOR ELEVATED SUPERCELLS IN THE
   WAA REGIME TO THE E OF THE MCS...WHERE LARGE HAIL WILL BE POSSIBLE.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
   MOTION VECTOR 29030.
   
   
   ...THOMPSON