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896 

WWUS20 KWNS 302058

SEL6

SPC WW 302058

NDZ000-310400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 506

NWS STORM PREDICTION CENTER NORMAN OK

300 PM MDT FRI AUG 30 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  WESTERN NORTH DAKOTA



* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 300 PM UNTIL

  1000 PM MDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL LARGE HAIL EVENTS WITH A FEW VERY LARGE HAIL EVENTS TO 2

    INCHES IN DIAMETER POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 70

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH

NORTHWEST OF MINOT NORTH DAKOTA TO 60 MILES SOUTH SOUTHEAST OF

DICKINSON NORTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH

SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 504...WW 505...



DISCUSSION...INCREASING CUMULUS IS INDICATED IN A N-S BAND ACROSS

WRN ND...NEAR A PRE-FRONTAL TROUGH AND AHEAD OF THE MAIN COLD FRONT

ADVANCING FROM THE NORTHWEST.  WITH MODERATE DESTABILIZATION HAVING

YIELDED A FAVORABLE ENVIRONMENT FOR STORM DEVELOPMENT...AND WITH

MODERATE MID-LEVEL FLOW SUPPORTIVE OF STORM

SUSTENANCE/ORGANIZATION...EXPECT STORM DEVELOPMENT AND SUBSEQUENT

INCREASE OVER THE NEXT 1-2 HOURS.  PRIMARY SEVERE THREATS WILL BE

LARGE HAIL AND DAMAGING WINDS...AS STORMS SPREAD EWD THROUGH THE

EVENING HOURS.



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 500. MEAN STORM

MOTION VECTOR 28030.





...GOSS

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