Alert archive / South Dakota / Mesoscale Discussions in 2026

Mesoscale Discussion 2012

August 17, 202619 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 17, 2026, 2:58 PM CDT for 19 counties in South Dakota. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Aug 17, 2026, 2:58 PM CDT (19:58 UTC)
Expired: Aug 17, 2026, 5:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch possible
Chance of a watch: 60%

Counties Brule County, SD, Buffalo County, SD, Corson County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Haakon County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jones County, SD, Lyman County, SD, Meade County, SD, Potter County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD, Ziebach County, SD

The radar

The Rapid City radar (KUDX), 165 km from the middle of the area, began a volume at 19:59 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 591Aug 17, 4:00 PM CDT

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Bennett, Brown, Buffalo, Campbell, Corson, Custer and 24 more	7 hr
Aug 17, 5:54 PM CDT	Mesoscale Discussion	SPC	Buffalo, Campbell, Corson, Dewey, Edmunds, Faulk and 16 more	66 min

Nearby

Mesoscale Discussions in South Dakota, 2026 Every mesoscale discussion 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; radar from the NEXRAD Level II archive.