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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 336
NWS Storm Prediction Center Norman OK
640 PM CDT Thu Jun 15 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southern and eastern Iowa
* Effective this Thursday night and Friday morning from 640 PM
until 100 AM CDT.
* Primary threats include...
Isolated very large hail events to 2 inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
SUMMARY...Multiple corridors of storms including some splitting
supercells will continue to progress generally eastward across the
region through the evening hours. Large hail and locally damaging
wind gusts are the main risk.
The severe thunderstorm watch area is approximately along and 75
statute miles north and south of a line from 20 miles northeast of
Cedar Rapids IA to 20 miles west of Falls City NE. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).
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 332...WW 333...WW
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