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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 430
NWS Storm Prediction Center Norman OK
735 PM CDT Fri Jul 21 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern South Dakota
* Effective this Friday night and Saturday morning from 735 PM
until 200 AM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Isolated very large hail events to 2 inches in diameter possible
SUMMARY...A relatively fast-moving line of storms across
north-central/northeast Minnesota early this evening will continue
southeastward into northwest Wisconsin and east-central Minnesota,
while additional storms will continue to develop within a moderately
unstable air mass across eastern South Dakota into west-central
Minnesota. Damaging winds and some severe hail are the main
The severe thunderstorm watch area is approximately along and 30
statute miles north and south of a line from 20 miles west of
Watertown SD to 145 miles east northeast of Saint Cloud MN. 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
OTHER WATCH INFORMATION...CONTINUE...WW 428...WW 429...
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