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WWUS20 KWNS 261933

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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 357

NWS STORM PREDICTION CENTER NORMAN OK

130 PM MDT THU JUN 26 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  EASTERN MONTANA

  NORTHEAST WYOMING



* EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 130 PM UNTIL

  900 PM MDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  A TORNADO OR TWO POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 105

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH

NORTHEAST OF GLASGOW MONTANA TO 60 MILES SOUTH SOUTHWEST OF

GILLETTE WYOMING.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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...MID/UPPER LEVEL TROUGH AND ASSOCIATED 40-50KT WIND MAX

WILL SPREAD NEWD ACROSS AN INCREASINGLY UNSTABLE AIRMASS ACROSS NERN

WY AND ERN MT THROUGH THE AFTERNOON. SEVERAL ROUNDS OF STRONG TO

SEVERE STORMS APPEAR POSSIBLE AS HEATING AND LARGE SCALE ASCENT ACT

TO REMOVE REMAINING CONVECTIVE INHIBITION AND ALLOW ROBUST STORMS TO

DEVELOP. WEAK LOW LEVEL E-SELY FLOW TOPPED BY 40-50KT SWLY MID-LEVEL

FLOW WILL SUPPORT STORM UPDRAFT ROTATION AND PERSISTENCE WITH

MAGNITUDE OF CAPE/SHEAR FAVORING LARGE HAIL AND PERHAPS EVEN A BRIEF

TORNADO. ACTIVITY MAY CONGEAL INTO SMALL CONVECTIVE COMPLEX BY

EVENING WITH SOME WIND DAMAGE POTENTIAL ACCOMPANYING THAT UPSCALE

DEVELOPMENT PROCESS.



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 25020.





...CARBIN

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