

000 

WWUS20 KWNS 101821

SEL7

SPC WW 101821

IAZ000-ILZ000-INZ000-WIZ000-LMZ000-110300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 677

NWS STORM PREDICTION CENTER NORMAN OK

120 PM CDT THU JUL 10 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EASTERN IOWA

       NORTHERN ILLINOIS

       FAR NORTHWEST INDIANA

       SOUTHERN WISCONSIN

       LAKE MICHIGAN



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 120 PM UNTIL

1000 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 80

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES NORTHWEST

OF CEDAR RAPIDS IOWA TO 15 MILES SOUTHEAST OF RACINE WISCONSIN.

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 676...



DISCUSSION...COMPLEX SCENARIO UNFOLDING ACROSS THE REGION THIS

AFTERNOON WITH A SLOW MOVING MID LEVEL TROUGH SHIFTING EWD AND

SUSTAINING INTENSE STORMS OVER ERN IA/SRN WI/NRN IL.  ADDITIONAL

THREAT WILL POSSIBLY DEVELOP SEWD ACROSS THE NRN MS RIVER VALLEY

LATER TODAY.  AIR MASS CONTINUES TO DESTABILIZE OVER THE REGION WITH

30-40 KT EFFECTIVE SHEAR SUSTAINING THREATS OF SUPERCELLS AND MORE

ORGANIZED LINES/CLUSTERS.  DAMAGING WINDS AND LARGE HAIL CAN BE

EXPECTED WITH THE STRONGER STORMS.



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 27025.





...EVANS

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