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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
* 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
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).
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.