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   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 431
   NWS STORM PREDICTION CENTER NORMAN OK
   1125 AM MDT SUN JUN 4 2006
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          CENTRAL IDAHO
          WESTERN MONTANA
   
   EFFECTIVE THIS SUNDAY MORNING AND EVENING FROM 1125 AM UNTIL 600
   PM MDT.
   
   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 APPROXIMATELY ALONG AND 95
   STATUTE MILES NORTH AND SOUTH OF A LINE FROM 55 MILES NORTHWEST
   OF MC CALL IDAHO TO 60 MILES NORTH NORTHEAST OF LIVINGSTON
   MONTANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
   ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).
   
   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...VIGOROUS S/WV TROUGH OR/WA MOVING RAPIDLY EWD WITH AIR
   MASS DESTABILIZING INTO WRN MT.  THUNDERSTORMS WILL INCREASE IN
   NUMBER AND INTENSITY ACROSS CENTRAL ID AND EVOLVE INTO SHORT
   LINES/BOWS.  WIND DAMAGE POTENTIAL WILL INCREASE AS STORMS DEVELOP.
   
   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 24035.
   
   
   ...HALES