

804 

WWUS20 KWNS 102049

SEL1

SPC WW 102049

SDZ000-WYZ000-110400-



URGENT - IMMEDIATE BROADCAST REQUESTED

Tornado Watch Number 171

NWS Storm Prediction Center Norman OK

250 PM MDT Sun Jun 10 2018



The NWS Storm Prediction Center has issued a



* Tornado Watch for portions of

  Western South Dakota

  Northeast Wyoming



* Effective this Sunday afternoon and evening from 250 PM until

  1000 PM MDT.



* Primary threats include...

  A few tornadoes and a couple intense tornadoes possible

  Scattered damaging winds and isolated significant gusts to 80

    mph likely

  Scattered large hail and isolated very large hail events to 3

    inches in diameter likely



SUMMARY...Storms will develop along and behind a cold front from the

Big Horns and Black Hills within a favorable environment for

supercells capable of producing all hazards. With time this evening,

these cells should merge into a line which develop bowing structures

as it spreads east towards the Missouri River, enhancing the risk

for severe wind gusts.



The tornado watch area is approximately along and 95 statute miles

east and west of a line from 70 miles east northeast of Buffalo SD

to 35 miles west southwest of Rapid City SD. For a complete

depiction of the watch see the associated watch outline update

(WOUS64 KWNS WOU1).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A Tornado Watch means conditions are favorable for

tornadoes and 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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 168...WW 169...WW 170...



AVIATION...Tornadoes and a few severe thunderstorms with hail

surface and aloft to 3 inches. Extreme turbulence and surface wind

gusts to 70 knots. A few cumulonimbi with maximum tops to 550. Mean

storm motion vector 22030.



...Grams

