

263 

WWUS20 KWNS 122333

SEL0

SPC WW 122333

NEZ000-SDZ000-WYZ000-130800-



URGENT - IMMEDIATE BROADCAST REQUESTED

Tornado Watch Number 320

NWS Storm Prediction Center Norman OK

535 PM MDT Mon Jun 12 2017



The NWS Storm Prediction Center has issued a



* Tornado Watch for portions of

  Northwestern Nebraska

  Western and southern South Dakota

  Northeastern Wyoming



* Effective this Monday afternoon and Tuesday morning from 535 PM

  until 200 AM MDT.



* Primary threats include...

  A few tornadoes possible

  Scattered damaging winds and isolated significant gusts to 80

    mph possible

  Scattered large hail and isolated very large hail events to 4

    inches in diameter possible



SUMMARY...Supercells should move into the watch area from the

southwest, offering a threat for tornadoes and large to giant hail.

Activity should evolve into one or two complexes of storms with an

increasing risk of severe wind later this evening into tonight,

across the Badlands/Black Hills region and points northeast from

there.



The tornado watch area is approximately along and 100 statute miles

east and west of a line from 90 miles northwest of Rapid City SD to

55 miles southwest of Valentine NE. For a complete depiction of the

watch see the associated watch outline update (WOUS64 KWNS WOU0).



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 316...WW 317...WW

318...WW 319...



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

surface and aloft to 4 inches. Extreme turbulence and surface wind

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

storm motion vector 22035.



...Edwards

