Alert archive / South Dakota / Mesoscale Discussions in 2026

Mesoscale Discussion 2017

August 17, 202622 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 17, 2026, 5:54 PM CDT for 22 counties in South Dakota. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued: Aug 17, 2026, 5:54 PM CDT (22:54 UTC)
Expired: Aug 17, 2026, 7:00 PM CDT
In force: 66 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 591

All 22 counties

Buffalo County, SD, Campbell 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, Jackson County, SD, Jones County, SD, Lyman County, SD, Meade County, SD, Mellette County, SD, Oglala Lakota County, SD, Pennington County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD, Ziebach County, SD

The radar

The Rapid City radar (KUDX), 172 km from the middle of the area, began a volume at 22:54 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 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, 2:58 PM CDT	Mesoscale Discussion	SPC	Brule, Buffalo, Corson, Dewey, Edmunds, Faulk and 13 more	2 hr
Aug 17, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Bennett, Brown, Buffalo, Campbell, Corson, Custer and 24 more	7 hr

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.