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URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 409
NWS Storm Prediction Center Norman OK
655 PM CDT Tue Jul 11 2017
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern South Dakota
* Effective this Tuesday evening from 655 PM until 1100 PM CDT.
* Primary threats include...
Isolated very large hail events to 2 inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
SUMMARY...Scattered thunderstorms will persist through late evening,
some of which could be supercells. The strongest storms will have
the potential to produce large hail and isolated damaging winds.
The severe thunderstorm watch area is approximately along and 50
statute miles east and west of a line from 40 miles north of
Ortonville MN to 35 miles east southeast of Mitchell SD. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).
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 408...
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 600. Mean storm motion vector