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WWUS20 KWNS 172312

SEL3

SPC WW 172312

IAZ000-MNZ000-NEZ000-SDZ000-180600-



URGENT - IMMEDIATE BROADCAST REQUESTED

Severe Thunderstorm Watch Number 593

NWS Storm Prediction Center Norman OK

615 PM CDT Sat Aug 17 2019



The NWS Storm Prediction Center has issued a



* Severe Thunderstorm Watch for portions of

  Northwest Iowa

  Southwest Minnesota

  Northeast Nebraska

  Eastern South Dakota



* Effective this Saturday night and Sunday morning from 615 PM

  until 100 AM CDT.



* Primary threats include...

  Scattered damaging winds likely with isolated significant gusts

    to 75 mph possible

  Scattered large hail and isolated very large hail events to 2

    inches in diameter possible

  A tornado or two possible



SUMMARY...Ongoing storms across south-central/northeast South Dakota

early this evening will continue eastward, with the possibility of

additional/more isolated supercell development ahead of an evolving

cluster of storms. Some tornado risk may exist for a time,

particularly through mid-evening across southeast South Dakota.

However, the overall most common risks should be large hail and

damaging winds, which should become more of a concern later this

evening as storm mergers occur and a more organized cluster/line

develops.



The severe thunderstorm watch area is approximately along and 130

statute miles north and south of a line from 30 miles north

northeast of Worthington MN to 45 miles west southwest of Huron SD.

For a complete depiction of the watch see the associated watch

outline update (WOUS64 KWNS WOU3).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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

tornadoes.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 590...WW 591...WW 592...



AVIATION...A few severe thunderstorms with hail surface and aloft to

2 inches. Extreme turbulence and surface wind gusts to 65 knots. A

few cumulonimbi with maximum tops to 600. Mean storm motion vector

28025.



...Guyer

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