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WWUS20 KWNS 241815

SEL6

SPC WW 241815

MNZ000-NDZ000-250100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 496

NWS STORM PREDICTION CENTER NORMAN OK

115 PM CDT SAT AUG 24 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHWESTERN MINNESOTA

  NORTHEASTERN NORTH DAKOTA



* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 115 PM UNTIL

  800 PM CDT.



* 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 110

STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHWEST OF

HALLOCK MINNESOTA TO 60 MILES SOUTH OF DEVILS LAKE 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.



&&



DISCUSSION...STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND

INTENSITY FROM NORTHEASTERN NORTH DAKOTA INTO NORTHWESTERN MINNESOTA

ALONG AND OUTFLOW BOUNDARY AND PRE-FRONTAL CONFLUENCE ZONE.

MODERATE-STRONG INSTABILITY WITH MLCAPE FROM 2000-3000 J/KG AND

25-35 KT EFFECTIVE SHEAR WILL SUPPORT BOTH MULTICELL AND SOME

SUPERCELL STRUCTURES WITH ACTIVITY POSSIBLY EVOLVING INTO

CLUSTERS/LINES THIS EVENING. DAMAGING WIND AND LARGE HAIL WILL BE

THE MAIN 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 500. MEAN STORM

MOTION VECTOR 25025.





...DIAL

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