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WWUS20 KWNS 212103

SEL1

SPC WW 212103

ARZ000-OKZ000-TXZ000-220500-



URGENT - IMMEDIATE BROADCAST REQUESTED

Tornado Watch Number 1

NWS Storm Prediction Center Norman OK

305 PM CST Sun Jan 21 2018



The NWS Storm Prediction Center has issued a



* Tornado Watch for portions of

  Western Arkansas

  Eastern Oklahoma

  Northeastern Texas



* Effective this Sunday afternoon and evening from 305 PM until

  1100 PM CST.



* Primary threats include...

  A few tornadoes possible

  Scattered damaging wind gusts to 70 mph possible



SUMMARY...Thunderstorms will continue to slowly increase in coverage

and intensity this afternoon into this evening from north and

northeastern Texas into southeastern Oklahoma and western Arkansas

in advance of a strong storm system progressing eastward over the

Great Plains.  The storm environment will support some threat for

semi-discrete supercells for the next few hours, and then convection

should gradually grow upscale into more of a squall line tonight.  A

few tornadoes with the supercells and/or embedded circulations, as

well as damaging winds with bowing segments, will be possible.



The tornado watch area is approximately along and 65 statute miles

east and west of a line from 30 miles west northwest of Harrison AR

to 50 miles south southwest of Tyler TX. 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.



&&



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

surface and aloft to 0.5 inches. Extreme turbulence and surface wind

gusts to 60 knots. A few cumulonimbi with maximum tops to 400. Mean

storm motion vector 22040.



...Thompson

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