⚠️ Severe Thunderstorm Warning – Custer, SD; Fall River, SD – Wednesday, August 12, 2026

Severe Thunderstorm Warning issued August 12 at 3:57PM MDT until August 12 at 4:30PM MDT by NWS Rapid City SD

Details

SVRUNR

The National Weather Service in Rapid City has issued a

* Severe Thunderstorm Warning for…
South Central Custer County in southwestern South Dakota…
Northeastern Fall River County in southwestern South Dakota…

* Until 430 PM MDT.

* At 357 PM MDT, a severe thunderstorm was located over Cottonwood
Springs Dam, or 5 miles west of Hot Springs, moving east at 40 mph.

HAZARD…Tennis ball size hail and 70 mph wind gusts.

SOURCE…Radar indicated.

IMPACT…People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect
considerable tree damage. Wind damage is also likely to
mobile homes, roofs, and outbuildings.

* Locations impacted include…
Hot Springs, Oral, Buffalo Gap, Oelrichs, Smithwick, Argyle,
Maverick Junction, Angostura Reservoir, Cold Brook Reservoir,
Cottonwood Springs Dam, Cascade Falls, southwestern Wind Cave
National Park and Hay Canyon Butte.

Instructions

Anyone outdoors should move to shelter inside a well-built structure
and stay away from windows. This storm is capable of producing
widespread damaging winds and dangerous hail.

If on or near Angostura Reservoir, get away from the water and move
indoors or inside a vehicle. Remember, lightning can strike out to 15
miles from the parent thunderstorm. If you can hear thunder, you are
close enough to be struck by lightning. Move to safe shelter now! Do
not be caught on the water in a thunderstorm.

This alert was automatically posted by SkyGuard, MWSC’s severe weather alerting system. Source: National Weather Service.