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455 

WWUS20 KWNS 312310

SEL6

SPC WW 312310

MNZ000-NDZ000-010500-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 556

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT SAT JUL 31 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST MINNESOTA

       NORTHERN NORTH DAKOTA



EFFECTIVE THIS SATURDAY NIGHT FROM 615 PM UNTIL MIDNIGHT CDT.



HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 20 MILES NORTHWEST

OF WILLISTON NORTH DAKOTA TO 35 MILES SOUTHEAST OF HALLOCK

MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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 552...WW 553...WW

554...WW 555...



DISCUSSION...ISOLATED SUPERCELL STORMS HAVE FORMED ALONG AND NORTH

OF THE ND-CANADIAN BORDER...DRIFTING SLOWLY SOUTHEASTWARD.  THESE

STORMS WILL POSE A RISK OF LARGE HAIL AND DAMAGING WINDS THROUGH THE

EVENING BEFORE WEAKENING AFTER DARK.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 32030.





...HART

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