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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 478
NWS Storm Prediction Center Norman OK
430 PM EDT Mon Sep 4 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and northeastern Indiana
Southeastern Lower Michigan
* Effective this Monday afternoon and evening from 430 PM until
1100 PM EDT.
* Primary threats include...
Widespread damaging wind gusts to 70 mph likely
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Thunderstorm development is expected in the next 1-2 hours
along a cold front moving southeastward across Lower Michigan and
northern Indiana. The storms should evolve rather quickly into a
line, and the storm environment will favor damaging winds with most
storms in the squall line through late evening.
The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 20 miles north
northwest of Terre Haute IN to 35 miles southeast of Mount Clemens
MI. 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 500. Mean storm motion vector