Alert archive / South Dakota / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 202, NWS Aberdeen, SD

August 11, 2026Corson County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at Aug 11, 2026, 8:04 PM MDT for Corson County, South Dakota. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 11, 2026, 8:04 PM MDT (02:04 UTC)
Expired
Aug 11, 2026, 8:45 PM MDT
In force
41 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Damage threat
Considerable
Hail
2.5 in
Wind
60.0 mph

County Corson County, SD

The radar

The Bismarck radar (KBIS), 123 km from the middle of the area, began a volume at 02:05 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 11, 4:40 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 00:00Z, 2.1 hours before the alert went out and 225 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Rapid City, SD at 00:00Z on 2026-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3392 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 2026-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3392 J/kg
Mixed-layer CIN
-82 J/kg
Mixed-layer LCL
1003 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
26 m²/s²
Significant tornado parameter
0.4
Supercell composite
1.9

Open this sounding in Storm Lab

The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 8:28 PM MDTSevere Thunderstorm Warning Considerable damage threatABRCorson23 min
Aug 11, 8:42 PM MDTSevere Thunderstorm WarningABRCorson10 min
Aug 11, 9:48 PM MDTSevere Thunderstorm Warning Considerable damage threatABRCorson42 min
Aug 11, 10:00 PM MDTSevere Thunderstorm Warning Considerable damage threatABRJones, Stanley60 min
Aug 12, 4:27 PM MDTSpecial Weather StatementABRMcPherson33 min
Aug 12, 4:39 PM MDTSevere Thunderstorm WarningABRMcPherson15 min
Aug 12, 5:03 PM MDTSpecial Weather StatementABRPotter27 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.