SEL7
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   SEVERE THUNDERSTORM WATCH NUMBER 307
   NWS STORM PREDICTION CENTER NORMAN OK
   830 PM MDT FRI MAY 20 2005
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
   
          NORTHEASTERN MONTANA
          FAR NORTHWESTERN NORTH DAKOTA
   
   EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 830 PM UNTIL
   100 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 APPROXIMATELY ALONG AND 45
   STATUTE MILES NORTH AND SOUTH OF A LINE FROM 100 MILES WEST OF
   GLENDIVE MONTANA TO 50 MILES EAST SOUTHEAST OF WILLISTON NORTH
   DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
   WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).
   
   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 302...WW 303...WW 304...WW
   305...WW 306...
   
   DISCUSSION...STRONG ASCENT ALONG AND NORTH OF DEEPENING SURFACE LOW
   AND ASSOCIATED FRONT WILL INCREASE STORMS ACROSS WW TONIGHT.  THOUGH
   CAPE FIELDS ARE ONLY MARGINAL...INSTABILITY AND SHEAR APPEAR TO BE
   MORE THAN SUFFICIENT FOR INTENSE THUNDERSTORMS WITH PRIMARY THREAT
   OF LARGE HAIL. ISOLATED WIND DAMAGE MAY OCCUR WITH STORMS ROOTING
   NEAR THE FRONT.
   
   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 500. MEAN STORM
   MOTION VECTOR 24035.
   
   
   ...EVANS