Alert archive / South Dakota / Mesoscale Discussions in 2020

Mesoscale Discussion 1602

August 27, 20204 states

The Storm Prediction Center issued this mesoscale discussion at Aug 27, 2020, 4:52 PM MDT for 4 states. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Aug 27, 2020, 4:52 PM MDT (22:52 UTC)
Expired: Aug 27, 2020, 6:15 PM MDT
In force: 83 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch likely
Chance of a watch: 95%

All 25 counties

Carter County, MT, Custer County, MT, Fallon County, MT, Powder River County, MT, Wibaux County, MT, Adams County, ND, Bowman County, ND, Golden Valley County, ND, Hettinger County, ND, Slope County, ND, Stark County, ND, Butte County, SD, Custer County, SD, Fall River County, SD, Harding County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Ziebach County, SD, Campbell County, WY, Crook County, WY, Niobrara County, WY, Weston County, WY

The radar

The Rapid City radar (KUDX), 125 km from the middle of the area, began a volume at 22:55 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 460Aug 27, 5:30 PM MDT

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 26, 7:04 PM MDT	Mesoscale Discussion	SPC	Beaverhead, Deer Lodge, Gallatin, Madison, Park, Silver Bow	116 min
Aug 27, 1:27 PM MDT	Mesoscale Discussion	SPC	Big Horn, Carter, Custer, Powder River, Rosebud	3 hr
Aug 27, 5:31 PM MDT	Severe Thunderstorm Watch	SPC	Carter, Custer, Dawson, Fallon, Powder River, Prairie and 1 more	7 hr
Aug 26, 6:21 PM MDT	Mesoscale Discussion	SPC	Bennett, Jackson, Jones, Mellette, Oglala Lakota, Todd	114 min

Nearby

Mesoscale Discussions in South Dakota, 2020 Mesoscale Discussions in North Dakota, 2020 Mesoscale Discussions in Montana, 2020 Every mesoscale discussion in 2020

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.