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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 498
NWS Storm Prediction Center Norman OK
305 PM EDT Tue Sep 14 2021
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southern and eastern Lower Michigan
Extreme northwestern Ohio
* Effective this Tuesday afternoon and evening from 305 PM until
1100 PM EDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Thunderstorm development is underway, and additional
storms will form and intensify this afternoon in multiple bands
along and ahead of a surface cold front. The storm environment
favors a mix of storm clusters (with some supercell structures
possible) and line segments, with damaging winds to 70 mph and
isolated large hail of 1 to 1.5 inch diameter possible through late
The severe thunderstorm watch area is approximately along and 70
statute miles east and west of a line from 55 miles north northeast
of Bad Axe MI to 40 miles west southwest of Fort Wayne IN. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU8).
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
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector