850
WWUS20 KWNS 111220
SEL3
SPC WW 111220
IAZ000-ILZ000-INZ000-WIZ000-LMZ000-111900-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 563
NWS STORM PREDICTION CENTER NORMAN OK
720 AM CDT TUE AUG 11 2026
THE NWS STORM PREDICTION CENTER HAS ISSUED A
* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
EASTERN IOWA
NORTHERN AND CENTRAL ILLINOIS
NORTHWEST INDIANA
SOUTHWEST AND SOUTHERN WISCONSIN
LAKE MICHIGAN
* EFFECTIVE THIS TUESDAY MORNING AND AFTERNOON FROM 720 AM UNTIL
200 PM CDT.
* PRIMARY THREATS INCLUDE...
WIDESPREAD DAMAGING WINDS AND ISOLATED SIGNIFICANT GUSTS TO 85
MPH LIKELY
ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE
A TORNADO OR TWO POSSIBLE
SUMMARY...AN INTENSIFYING SQUALL LINE WILL CONTINUE EAST INTO THE
WATCH AREA THIS MORNING THROUGH THE MIDDAY. SEVERE GUSTS (60 TO 85
MPH) WILL LIKELY BECOME MORE PREVALENT AND WIDESPREAD AS THE SQUALL
LINE MATURES THROUGH THE LATE MORNING. AN EMBEDDED TORNADO OR TWO
IS POSSIBLE WITHIN THE SQUALL LINE.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 100
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 30 MILES WEST SOUTHWEST
OF DUBUQUE IA TO 80 MILES EAST OF MARSEILLES IL. FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU3).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO
1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 75 KNOTS. A
FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR
28040.
...SMITH
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