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WWUS20 KWNS 071808

SEL9

SPC WW 071808

ILZ000-INZ000-LMZ000-080200-



URGENT - IMMEDIATE BROADCAST REQUESTED

Severe Thunderstorm Watch Number 489

NWS Storm Prediction Center Norman OK

110 PM CDT Tue Sep 7 2021



The NWS Storm Prediction Center has issued a



* Severe Thunderstorm Watch for portions of

  Northern Illinois

  Northwest Indiana

  Lake Michigan



* Effective this Tuesday afternoon and evening from 110 PM until

  900 PM CDT.



* Primary threats include...

  Scattered large hail likely with isolated very large hail events

    to 2 inches in diameter possible

  Scattered damaging wind gusts to 70 mph likely



SUMMARY...A line of thunderstorms currently developing from northern

Illinois into eastern Iowa will spread across the watch area this

afternoon and early evening.  Damaging winds and hail will be

possible with the strongest cells.



The severe thunderstorm watch area is approximately along and 60

statute miles north and south of a line from 85 miles east of

Marseilles IL to 45 miles west northwest of Peoria IL. For a

complete depiction of the watch see the associated watch outline

update (WOUS64 KWNS WOU9).



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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 488...



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

26035.



...Hart

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