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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 435
NWS Storm Prediction Center Norman OK
330 AM CDT Sun Jul 23 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Central and southern Illinois
* Effective this Sunday morning from 330 AM until 800 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
SUMMARY...Thunderstorms with a history of severe gusts -- including
measured 62-kt gust at SET (St. Charles MO) at 802Z -- will continue
to offer a threat for damaging wind across the new watch area. The
complex should weaken over southeastern IL/southwestern Indiana as
it moves deeper into outflow air from earlier storms. WFO LSX has
extended watch 434 eastward into more of IL and this new watch wraps
around that extension.
The severe thunderstorm watch area is approximately along and 60
statute miles north and south of a line from 50 miles northwest of
Salem IL to 45 miles southeast of Mattoon IL. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU5).
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 434...
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE and ALOFT
TO 1 INCH. EXTREME TURBULENCE and SURFACE WIND GUSTS TO 65 KNOTS.
A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION