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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 429
NWS Storm Prediction Center Norman OK
450 PM CDT Fri Jul 21 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and Eastern Iowa
Southwest Lower Michigan
* Effective this Friday afternoon from 450 PM until Midnight CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
A tornado or two possible
SUMMARY...Multiple clusters of storms should continue to intensify
through late afternoon and early evening and spread
east-southeastward across the region. Damaging winds will be the
primary concern, although some severe hail may occur and a tornado
or two cannot be ruled out, particularly across parts of Iowa into
northern Illinois along a boundary.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 30 miles north of Des
Moines IA to 15 miles south southeast of South Bend IN. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).
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 428...
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 550. Mean storm motion vector