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788 

WWUS20 KWNS 032210

SEL0

SPC WW 032210

MTZ000-040600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 590

NWS STORM PREDICTION CENTER NORMAN OK

410 PM MDT SUN JUL 3 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND EASTERN MONTANA



EFFECTIVE THIS SUNDAY AFTERNOON FROM 410 PM UNTIL MIDNIGHT MDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

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 60 MILES SOUTHEAST OF

LIVINGSTON MONTANA TO 75 MILES NORTHWEST OF GLASGOW MONTANA.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 588...WW 589...



DISCUSSION...WITH CONTINUED SFC HEATING...TSTMS EXPECTED TO INCREASE

OVER THE NEXT FEW HOURS OVER THE HIGHER TERRAIN W AND SW OF BIL...W

OF LWT...AND...A BIT LATER...PERHAPS ALONG COLD FRONT W OF HVR.  TWO

OR THREE SMALL CLUSTERS OF STORMS SHOULD EVOLVE FROM THIS ACTIVITY.

40-50 KT LARGELY UNIDIRECTIONAL WSWLY CLOUD LAYER WIND PROFILES AND

STEEP LOW TO MID LVL LAPSE RATES SUGGEST LIKELIHOOD FOR BOWING

SEGMENTS AND EMBEDDED SUPERCELLS WITH HIGH WIND AND HAIL THROUGH

LATE EVE.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 24040.





...CORFIDI

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