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000 

WWUS20 KWNS 222307

SEL1

SPC WW 222307

MTZ000-NDZ000-230500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 731

NWS STORM PREDICTION CENTER NORMAN OK

505 PM MDT TUE JUL 22 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHEAST MONTANA

       FAR NORTHWEST NORTH DAKOTA



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 505 PM UNTIL

1100 PM 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 105

STATUTE MILES EAST AND WEST OF A LINE FROM 85 MILES WEST

SOUTHWEST OF GLENDIVE MONTANA TO 65 MILES NORTH NORTHEAST OF WOLF

POINT 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.



OTHER WATCH INFORMATION...CONTINUE...WW 725...WW 726...WW

727...WW 728...WW 729...WW 730...



DISCUSSION...STRONG TO SEVERE THUNDERSTORMS HAVE ALREADY FORMED LATE

TODAY OVER NERN MT.  ACTIVITY WILL CONTINUE TO INCREASE IN COVERAGE

AND INTENSITY THROUGH THE EVENING AHEAD OF APPROACHING MID/UPPER

LEVEL SHORTWAVE TROUGH.  AIR MASS IS EXPECTED TO REMAIN MODERATELY

UNSTABLE WITH INCREASING DEEP LAYER SHEAR BECOMING MORE SUPPORTIVE

OF A FEW ORGANIZED STORM CLUSTERS AND POSSIBLE SUPERCELLS.  DAMAGING

WINDS AND LARGE HAIL WILL BE PRIMARY SEVERE THREATS.



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 20020.





...EVANS

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