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628 

WWUS20 KWNS 270310

SEL9

SPC WW 270310

MNZ000-NDZ000-271000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 539

NWS STORM PREDICTION CENTER NORMAN OK

1010 PM CDT MON JUL 26 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHWEST MINNESOTA

       NORTHEAST NORTH DAKOTA



EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 1010 PM

UNTIL 500 AM CDT.



HAIL TO 2 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 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 55 MILES WEST

NORTHWEST OF GRAND FORKS NORTH DAKOTA TO 50 MILES NORTH NORTHEAST

OF BEMIDJI MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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 537...WW 538...



DISCUSSION...EVOLVING MCS IS EXPECTED TO CONTINUE EWD THROUGH THE

RED RIVER VALLEY IN ADVANCE OF MIDLEVEL TROUGH TRANSLATING EWD

THROUGH NRN ND.  WHILE CONVECTIVE INHIBITION IS INCREASING...FORCING

ASSOCIATED WITH THE MIDLEVEL PERTURBATION COUPLED WITH GROWING

MESOSCALE COLD POOLS SHOULD SERVE TO SUPPORT VIGOROUS UPDRAFT

REGENERATION.  GIVEN 40-50 KT OF DEEP WNWLY SHEAR...KINEMATIC

ENVIRONMENT WILL REMAIN FAVORABLE FOR BOWING STRUCTURES WITH THE

MAIN THREAT BEING DAMAGING WIND GUSTS.



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.





...MEAD

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