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URGENT - IMMEDIATE BROADCAST REQUESTED

Tornado Watch Number 280

NWS Storm Prediction Center Norman OK

340 PM CDT Wed Jul 18 2018



The NWS Storm Prediction Center has issued a



* Tornado Watch for portions of

  Northern Nebraska

  South Dakota



* Effective this Wednesday afternoon and evening from 340 PM

  until 1100 PM CDT.



* Primary threats include...

  A couple tornadoes possible

  Scattered large hail likely with isolated very large hail events

    to 2 inches in diameter possible

  Scattered damaging wind gusts to 70 mph possible



SUMMARY...On the southern periphery of an upper-level system moving

slowly eastward over the Dakotas, storms will continue to increase

in coverage and intensity through the remainder of the afternoon

into this evening. A relatively moist environment and strengthening

winds aloft (reference 19Z Rapid City special observed sounding)

will support supercells capable of large hail. A concern for a

couple of tornadoes also exists especially along a warm front that

extends across central/southern South Dakota into northern Nebraska.

Otherwise, storms will eventually cluster and move southeastward

across the region this evening with some increased potential for

damaging winds.



The tornado watch area is approximately along and 70 statute miles

north and south of a line from 70 miles northwest of Philip SD to 45

miles northeast of Oneill 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.



&&



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

surface and aloft to 2 inches. Extreme turbulence and surface wind

gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean

storm motion vector 29025.



...Guyer

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