

000 

WWUS20 KWNS 191928

SEL2

SPC WW 191928

MTZ000-200200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 842

NWS STORM PREDICTION CENTER NORMAN OK

130 PM MDT TUE AUG 19 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL MONTANA



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 130 PM UNTIL

800 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTHEAST OF

CUT BANK MONTANA TO 15 MILES SOUTH SOUTHEAST OF BUTTE MONTANA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU2).



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 841...



DISCUSSION...SCATTERED THUNDERSTORMS HAVE BEGUN TO FORM AHEAD OF

UPPER TROUGH MOVING INTO WESTERN MT.  THESE STORMS WILL SPREAD

NORTHEASTWARD THROUGH THE AFTERNOON AND EARLY EVENING ACROSS THE

WATCH AREA.  DESPITE LIMITED LOW LEVEL MOISTURE...STEEP LAPSE RATES

AND INCREASING WINDS ALOFT WILL POSE A RISK OF ISOLATED SEVERE

STORMS CAPABLE OF 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 22030.





...HART

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