336
WWUS20 KWNS 182145
SEL0
SPC WW 182145
SDZ000-190300-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 600
NWS Storm Prediction Center Norman OK
345 PM MDT Mon Aug 18 2025

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
  Western into Central South Dakota

* Effective this Monday afternoon and evening from 345 PM until
  900 PM MDT.

* Primary threats include...
  Scattered large hail and isolated very large hail events to 3
    inches in diameter possible
  Isolated damaging wind gusts to 70 mph possible

SUMMARY...Isolated supercells will likely continue to pose a risk
for large to very large hail (1 to 3 inches in diameter) through the
late afternoon and early evening.  A cluster of thunderstorms may
eventually evolve and gradually move east-southeast into central
South Dakota this evening.  The primary threats with the potential
thunderstorm cluster will be large hail and severe gusts (60-70
mph).

The severe thunderstorm watch area is approximately along and 85
statute miles north and south of a line from 35 miles north
northwest of Rapid City SD to 30 miles east northeast of Pierre SD.
For a complete depiction of the watch see the associated watch
outline update (WOUS64 KWNS WOU0).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for 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. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 599...

AVIATION...A few severe thunderstorms with hail surface and aloft to
3 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector
29015.

...Smith