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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 100
NWS Storm Prediction Center Norman OK
120 PM MDT Thu May 17 2018
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Extreme Southeast Montana
Western South Dakota
* Effective this Thursday afternoon and evening from 120 PM until
900 PM MDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Storms developing over northeast Wyoming and western South
Dakota are expected to increase in intensity this afternoon and
spread northeast through the evening posing a threat for large hail
and damaging wind gusts.
The severe thunderstorm watch area is approximately along and 80
statute miles east and west of a line from 50 miles east northeast
of Buffalo SD to 70 miles south of Rapid City SD. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU0).
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
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector