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819 

WWUS20 KWNS 230759

SEL8

SPC WW 230759

IAZ000-MNZ000-231300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 798

NWS STORM PREDICTION CENTER NORMAN OK

300 AM CDT TUE AUG 23 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTH-CENTRAL AND NORTHEAST IOWA

       SOUTHEAST MINNESOTA



EFFECTIVE THIS TUESDAY MORNING FROM 300 AM UNTIL 800 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 65

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

SOUTHWEST OF WATERLOO IOWA TO 25 MILES NORTHEAST OF ROCHESTER

MINNESOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).



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...BOWING MCS HAS EVOLVED OVER N-CNTRL IA THIS MORNING

WITH A RECENT GUST TO 75 MPH AT AXA.  EXPECT SYSTEM TO CONTINUE

ESEWD...FED ON SWRN FLANK BY 40 KT SWLY LLJ.  DAMAGING WINDS WILL

REMAIN THE PRIMARY HAZARD.



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 29035.





...MEAD

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