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WWUS20 KWNS 251952

SEL5

SPC WW 251952

MTZ000-NEZ000-SDZ000-WYZ000-260300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 355

NWS STORM PREDICTION CENTER NORMAN OK

150 PM MDT WED JUN 25 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  SOUTHEAST MONTANA

  WESTERN NEBRASKA

  WESTERN SOUTH DAKOTA

  CENTRAL AND EASTERN WYOMING



* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 150 PM

  UNTIL 900 PM MDT.



* PRIMARY THREATS INCLUDE...

  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE

  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 105

STATUTE MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH OF

BROADUS MONTANA TO 35 MILES EAST OF CHEYENNE WYOMING.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU5).



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...STORMS ARE EXPECTED TO INCREASE ACROSS THE REGION AS

LARGE SCALE ASCENT ASSOCIATED WITH WEAK HEIGHT FALLS SPREADS EAST.

VERY MOIST AIRMASS AND UPSLOPE FLOW WILL FURTHER CONTRIBUTE TO

CONVECTIVE DEVELOPMENT...INITIALLY ACROSS HIGHER TERRAIN...AND THEN

EAST ACROSS THE HIGH PLAINS. POCKETS OF EFFECTIVE SHEAR ON THE ORDER

OF 30-35KT MAY SUPPORT A FEW SUPERCELLS WITH STORM MERGERS

EVENTUALLY RESULTING IN LARGER COMPLEX OF STORMS SPREADING EAST THIS

EVENING. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREATS.



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 27025.





...CARBIN

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