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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 428
NWS Storm Prediction Center Norman OK
305 PM CDT Fri Jul 21 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast North Dakota
Northern South Dakota
* Effective this Friday afternoon and evening from 305 PM until
1100 PM CDT.
* Primary threats include...
Scattered large hail likely with 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...Strong to severe storms are expected to increase this
afternoon into the evening with a threat for large hail and damaging
wind. A tornado or two also cannot be ruled out.
The severe thunderstorm watch area is approximately along and 105
statute miles east and west of a line from 20 miles west northwest
of Thief River Falls MN to 60 miles south of Mobridge SD. 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
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector