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390 

WWUS20 KWNS 050320

SEL7

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IAZ000-MNZ000-050800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 617

NWS STORM PREDICTION CENTER NORMAN OK

1020 PM CDT TUE SEP 4 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN IOWA

       SOUTHERN MINNESOTA



EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1020 PM

UNTIL 300 AM CDT.



HAIL TO 1.5 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 45

STATUTE MILES EAST AND WEST OF A LINE FROM MANKATO MINNESOTA TO

25 MILES SOUTH SOUTHEAST OF FORT DODGE IOWA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU7).



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 614...WW 615...WW 616...



DISCUSSION...ORGANIZED MCS WILL CONTINUE TO POSE A THREAT FOR MAINLY

ISOLATED DAMAGING WIND AND LARGE HAIL NEXT FEW HOURS AS IT CONTINUES

THROUGH NRN IA AND SRN MN THROUGH THE EARLY MORNING. SEVERE THREAT

WILL BE SUPPORTED IN PART BY A SSWLY LLJ FROM MODERATELY UNSTABLE

WARM SECTOR AND 40 KT 0-6 KM SHEAR.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 27035.





...DIAL

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