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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 360

NWS STORM PREDICTION CENTER NORMAN OK

235 PM MDT TUE JUN 5 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTH-CENTRAL AND CENTRAL MONTANA



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL

1100 PM MDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 75 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 90 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES SOUTH SOUTHEAST OF

GREAT FALLS MONTANA TO 65 MILES EAST NORTHEAST OF CUT BANK

MONTANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 358...WW 359...



DISCUSSION...MIGRATORY SURFACE LOW NEAR LVM WILL DEVELOP NWD ALONG

N-S ORIENTED WARM FRONT TO VICINITY OF HVR BY LATE EVENING.  AIR

MASS ALONG THIS BOUNDARY IS QUITE MOIST GIVEN THE ELEVATION WITH

DEWPOINTS IN THE MID 50S-LOWER 60S.  WHEN COUPLED WITH STEEP

MIDLEVEL LAPSE RATES...ENVIRONMENT IS MODERATELY UNSTABLE WITH

MLCAPE OF 1000-2000 J/KG AND A DECREASING CAP.  EXPECT TSTMS TO

INCREASE IN COVERAGE AND INTENSITY THIS AFTERNOON INTO EVENING IN

RESPONSE TO APPROACH OF NEGATIVELY TILTED MIDLEVEL TROUGH.  FORECAST

HODOGRAPHS ALONG THE WARM FRONT DEPICT SIZABLE LOW- AND DEEP-LAYER

SHEAR WHICH WILL SUPPORT SUPERCELLS CAPABLE OF A FEW TORNADOES...IN

ADDITION TO VERY LARGE HAIL AND DAMAGING WINDS.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 17035.





...MEAD

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