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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 425
NWS Storm Prediction Center Norman OK
855 AM CDT Mon Aug 10 2020
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
* Effective this Monday morning and afternoon from 855 AM until
200 PM CDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 80 mph possible
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...A fast-moving cluster over western Iowa with a history of
severe wind gusts should expand and intensify as it sweeps across
central Iowa through early afternoon. Damaging winds are the primary
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 40 miles south of Storm
Lake IA to 45 miles north of Ottumwa IA. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
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 424...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector