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000 

WWUS20 KWNS 311951

SEL4

SPC WW 311951

IAZ000-MNZ000-010200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 404

NWS STORM PREDICTION CENTER NORMAN OK

250 PM CDT SAT MAY 31 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHEAST IOWA

       MINNESOTA



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 250 PM UNTIL

900 PM 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 50

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES WEST

NORTHWEST OF BEMIDJI MINNESOTA TO 80 MILES SOUTH SOUTHEAST OF

ROCHESTER 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.



OTHER WATCH INFORMATION...CONTINUE...WW 402...WW 403...



DISCUSSION...MID LEVEL IMPULSE AND ASSOCIATED SURFACE LOW DIVING

SEWD INTO NRN MN LATE THIS AFTERNOON SHOULD ENHANCE THUNDERSTORMS

ALONG NW-SE ORIENTED SURFACE FRONT ACROSS WW.  AIR MASS IS MARGINAL

TO MODERATELY UNSTABLE NEAR AND WEST OF THE FRONT SHOULD SUSTAIN

STRONGER CORES...WHILE EFFECTIVE SHEAR TO 35-40 KT SUPPORTS

ORGANIZED STORMS INCLUDING BRIEF SUPERCELLS.  LARGE HAIL WILL BE

PRIMARY SEVERE THREAT...ALTHOUGH ISOLATED DAMAGING WINDS AND

FUNNELS/A BRIEF-LIVED TORNADO ARE ALSO POSSIBLE.



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 400. MEAN STORM

MOTION VECTOR 30025.





...EVANS

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