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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 426
NWS Storm Prediction Center Norman OK
1125 AM CDT Mon Aug 10 2020
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Far northwest Indiana
Far southern Wisconsin
* Effective this Monday morning and evening from 1125 AM until
700 PM CDT.
...THIS IS A PARTICULARLY DANGEROUS SITUATION...
* Primary threats include...
Widespread damaging winds and scattered significant gusts to 100
Isolated large hail events to 1.5 inches in diameter possible
A couple tornadoes possible
SUMMARY...A derecho will rapidly progress across eastern Iowa and
northern Illinois this afternoon. Widespread severe wind gusts, some
of which should reach 80-100 mph are anticipated along the track of
the bow. Brief tornadoes are also possible.
The severe thunderstorm watch area is approximately along and 85
statute miles north and south of a line from 20 miles west southwest
of Cedar Rapids IA to 75 miles south southeast of Racine WI. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU6).
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
OTHER WATCH INFORMATION...CONTINUE...WW 425...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 85 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector