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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 301
NWS Storm Prediction Center Norman OK
410 PM MDT Sat Jul 21 2018
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Far Eastern Montana
Western North Dakota
Western South Dakota
* Effective this Saturday afternoon and evening from 410 PM until
1100 PM MDT.
* Primary threats include...
Scattered large hail likely with isolated very large hail events
to 2.5 inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Storms will continue to develop and intensify in several
different areas across the region, including a well-organized
cluster of storms already ongoing across northeast Montana into
northwest North Dakota. Large hail and damaging winds will be the
primary concerns as storms, including a few supercells, spread
east/southeastward across a relatively narrow axis of moderately
unstable air through this evening.
The severe thunderstorm watch area is approximately along and 55
statute miles east and west of a line from 25 miles north northeast
of Sidney MT to 55 miles southwest of Rapid City SD. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).
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 300...
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 550. Mean storm motion vector