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WWUS20 KWNS 170322

SEL2

SPC WW 170322

IAZ000-ILZ000-WIZ000-LMZ000-171000-



URGENT - IMMEDIATE BROADCAST REQUESTED

Severe Thunderstorm Watch Number 342

NWS Storm Prediction Center Norman OK

1025 PM CDT Fri Jun 16 2017



The NWS Storm Prediction Center has issued a



* Severe Thunderstorm Watch for portions of

  Eastern Iowa

  Northern Illinois

  Southern Wisconsin

  Lake Michigan



* Effective this Friday night and Saturday morning from 1025 PM

  until 500 AM CDT.



* Primary threats include...

  Scattered large hail and isolated very large hail events to 2

    inches in diameter possible

  Isolated damaging wind gusts to 70 mph possible



SUMMARY...A weak mid-level disturbance or two combined with

residually steep lapse rates and moderate deep-layer shear will

continue to pose at least an episodic severe risk mainly in the form

of large hail and locally damaging winds as storms spread eastward

late this evening into the overnight.



The severe thunderstorm watch area is approximately along and 60

statute miles east and west of a line from 30 miles northwest of

Milwaukee WI to 45 miles west southwest of Moline IL. For a complete

depiction of the watch see the associated watch outline update

(WOUS64 KWNS WOU2).



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 341...



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 600. Mean storm motion vector

28025.



...Guyer

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