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   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 421
   NWS STORM PREDICTION CENTER NORMAN OK
   605 PM EDT WED JUN 9 2004
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          CENTRAL AND SOUTHERN LOWER MICHIGAN
          LAKE MICHIGAN
          LAKE HURON
   
   EFFECTIVE THIS WEDNESDAY NIGHT FROM 605 PM UNTIL MIDNIGHT EDT.
   
   HAIL TO 1.5 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 55 STATUTE MILES
   NORTH AND SOUTH OF A LINE FROM 20 MILES WEST NORTHWEST OF MUSKEGON
   MICHIGAN TO 35 MILES NORTH NORTHEAST OF MOUNT CLEMENS MICHIGAN.
   
   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...THIS SEVERE THUNDERSTORM WATCH REPLACES
   SEVERE THUNDERSTORM WATCH NUMBER 414. WATCH NUMBER 414 WILL NOT BE
   IN EFFECT AFTER 605 PM EDT. CONTINUE...WW 417...WW 418...WW
   419...WW 420...
   
   DISCUSSION...THUNDERSTORMS...INCLUDING POSSIBLE ROTATING
   STORMS...EXPECTED TO CONTINUE DEVELOPING IN ZONE OF STRONG
   SURFACE-BASED INSTABILITY /MLCAPE TO 2000 J/KG/ ALONG AND S OF W/E
   ORIENTED COLD FRONT.
   
   AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
   TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
   KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
   MOTION VECTOR 26030.
   
   
   ...CORFIDI