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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 425
NWS Storm Prediction Center Norman OK
250 PM MDT Thu Jul 20 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Western North Dakota
Northwest South Dakota
* Effective this Thursday afternoon and evening from 250 PM until
1000 PM MDT.
* Primary threats include...
Scattered large hail likely with isolated very large hail events
to 2.5 inches in diameter possible
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Thunderstorms will continue to intensify over the watch
area this afternoon and early evening, posing a threat of very 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 60 miles north northeast
of Williston ND to 40 miles south southwest of Buffalo SD. 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 424...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector