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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 454

NWS STORM PREDICTION CENTER NORMAN OK

1145 AM CDT MON JUL 2 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN MINNESOTA

       FAR EASTERN NORTH DAKOTA



EFFECTIVE THIS MONDAY MORNING AND EVENING FROM 1145 AM UNTIL 700

PM CDT.



HAIL TO 2.5 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 75

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

GRAND FORKS NORTH DAKOTA TO 85 MILES EAST OF BEMIDJI MINNESOTA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU4).



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...ELEVATED TSTMS THAT HAVE BEEN PERCOLATING ALL MORNING

OVER CNTRL/NRN ND ARE EXPECTED TO BECOME SFC BASED THIS AFTN AS

BOUNDARY LAYER HEATS AMIDST LWR 70S DEW POINTS.  INITIAL ACTIVITY

WILL LIKELY ATTAIN SUPERCELL CHARACTER AS DEEP LAYER SHEAR OF 35-40

KTS EXISTS ALONG WITH VERY STEEP MID-LVL LAPSE RATES.  VERY LARGE

HAIL WILL BE THE PRIMARY RISK...ALTHOUGH A BRIEF TORNADO CANNOT BE

RULED OUT.  MEANWHILE...AS COLD POOLS CONGLOMERATE LATER THIS AFTN

AND EVE...ACTIVITY SHOULD GRADUALLY EVOLVE INTO A BOW ECHO OVER NRN

MN.  HERE...4000 J/KG MLCAPE...AT LEAST 40 KTS OF WLY MID-LVL FLOW

AND SUFFICIENT BOUNDARY LAYER INFLOW SUGGEST THAT DMGG WIND GUSTS

WILL PRIMARY SVR THREAT WITH CORRIDORS OF SIG WIND PSBL.



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

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 26035.





...RACY

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