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WWUS20 KWNS 110836

SEL4

SPC WW 110836

IAZ000-ILZ000-MNZ000-WIZ000-LMZ000-111600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 624

NWS STORM PREDICTION CENTER NORMAN OK

330 AM CDT MON JUL 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN IOWA

       NORTHWEST ILLINOIS

       PARTS OF SOUTHEAST MINNESOTA

       SOUTHERN WISCONSIN

       LAKE MICHIGAN



EFFECTIVE THIS MONDAY MORNING FROM 330 AM UNTIL 1100 AM CDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

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

NORTHEAST OF LONEROCK WISCONSIN TO 45 MILES SOUTH OF CEDAR RAPIDS

IOWA.  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 620...WW 622...WW 623...



DISCUSSION...FORWARD-PROPAGATING MCS NOW EVOLVING NEAR DSM EXPECTED

TO CONTINUE GENERALLY E AT 35-40 KTS...WHILE N/S SQLN IN CNTRL/SW WI

CONTINUES E AT ABOUT THE SAME SPEED.  ASSOCIATED BOWING

SEGMENTS...ESPECIALLY WITH THE IA MCS...COULD YIELD DMGG WIND EWD

ACROSS ERN IA...NW IL AND ERN WI GIVEN CURRENT AND EXPECTED

WIND/THERMODYNAMIC ENVIRONMENT IN WW AREA.  IN ADDITION...AS

TRAILING WRN PART OF OUTFLOW BOUNDARY LEFT BY WI SYSTEM BECOMES

STNRY OVER NE IA/SRN WI...IT TOO COULD SERVE AS A FOCUS FOR STRONG

FORWARD-PROPAGATING SEGMENTS/BOWS LATER THIS MORNING.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 27035.





...CORFIDI

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