

845 

WWUS20 KWNS 120036

SEL2

SPC WW 120036

NDZ000-SDZ000-120700-



URGENT - IMMEDIATE BROADCAST REQUESTED

Severe Thunderstorm Watch Number 432

NWS Storm Prediction Center Norman OK

635 PM MDT Tue Aug 11 2020



The NWS Storm Prediction Center has issued a



* Severe Thunderstorm Watch for portions of

  Southwestern North Dakota

  Northwestern South Dakota



* Effective this Tuesday night and Wednesday morning from 635 PM

  until 100 AM MDT.



* Primary threats include...

  Scattered damaging wind gusts to 70 mph possible

  Scattered large hail events to 1.5 inches in diameter possible



SUMMARY...Clusters of storms forming in southeastern Montana and

southwestern North Dakota may persist into the overnight hours while

spreading east-southeastward across northwestern South Dakota.  Some

supercell structures will be possible this evening, while upscale

growth into a cluster is expected tonight.  The strongest embedded

storms will be capable of producing damaging winds and large hail.



The severe thunderstorm watch area is approximately along and 45

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

Buffalo SD to 85 miles east southeast of Lemmon SD. For a complete

depiction of the watch see the associated watch outline update

(WOUS64 KWNS WOU2).



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.



&&



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

1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A

few cumulonimbi with maximum tops to 550. Mean storm motion vector

29020.



...Thompson

