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615 

WWUS20 KWNS 261720

SEL1

SPC WW 261720

MTZ000-262300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 431

NWS STORM PREDICTION CENTER NORMAN OK

1120 AM MDT TUE JUN 26 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST AND NORTH CENTRAL MONTANA



EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 1120 AM UNTIL

500 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 65

STATUTE MILES EITHER SIDE OF A LINE FROM 70 MILES SOUTH SOUTHWEST

OF CUT BANK MONTANA TO 40 MILES EAST OF HAVRE 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...STRONG STORMS HAVE DEVELOPED IN A BAND ALONG THE

LEADING EDGE OF INTENSE LARGE SCALE ASCENT ASSOCIATED WITH AN UPPER

SHORT WAVE TROUGH MOVING NEWD ACROSS THE NRN INTERMOUNTAIN REGION.

STEEP LAPSE RATES AND INCREASING MOISTURE WITH EWD EXTENT WILL

SUPPORT STRONG/SEVERE STORMS WITH POTENTIAL TO PRODUCE LARGE HAIL

AND DAMAGING WINDS.



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 450. MEAN STORM

MOTION VECTOR 22035.





...WEISS

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