Alert archive / South Dakota / Mesoscale Discussions in 2011
Mesoscale Discussion 1867
The Storm Prediction Center issued this mesoscale discussion at Aug 5, 2011, 4:25 PM MDT for 5 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 5, 2011, 4:25 PM MDT (22:25 UTC)
- Expired
- Aug 5, 2011, 6:30 PM MDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 54 counties
Big Horn County, MT, Carter County, MT, Custer County, MT, Fallon County, MT, Powder River County, MT, Prairie County, MT, Rosebud County, MT, Wibaux County, MT, Adams County, ND, Billings County, ND, Bowman County, ND, Burleigh County, ND, Dunn County, ND, Golden Valley County, ND, Grant County, ND, Hettinger County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Oliver County, ND, Sioux County, ND, Slope County, ND, Stark County, ND, Banner County, NE, Box Butte County, NE, Dawes County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Bennett County, SD, Butte County, SD, Corson County, SD, Custer County, SD, Dewey County, SD, Fall River County, SD, Haakon County, SD, Harding County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Stanley County, SD, Ziebach County, SD, Campbell County, WY, Crook County, WY, Goshen County, WY, Niobrara County, WY, Platte County, WY, Sheridan County, WY, Weston County, WY
The radar
The Rapid City radar (KUDX), 107 km from the middle of the area, began a volume at 22:25 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.
The nearest sounding before it
Rapid City, SD (KUNR), launched 12:00Z, 10.4 hours before the alert went out and 104 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.
- Mixed-layer CAPE
- 1650 J/kg
- Mixed-layer CIN
- -38 J/kg
- Mixed-layer LCL
- 1019 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -37 m²/s²
- 0-3 km storm-relative helicity
- -16 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 5, 12:05 PM MDT | Mesoscale Discussion | SPC | Big Horn, Carter, Custer, Fallon, Powder River, Prairie and 2 more | 2 hr |
| Aug 5, 2:55 PM MDT | Severe Thunderstorm Watch | SPC | Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 1 more | 5 hr |
| Aug 4, 7:17 PM MDT | Mesoscale Discussion | SPC | Arthur, Cherry, Cheyenne, Deuel, Garden, Grant and 5 more | 58 min |
| Aug 4, 6:40 PM MDT | Mesoscale Discussion | SPC | Adams, Billings, Bowman, Dunn, Golden Valley, Hettinger and 2 more | 95 min |
| Aug 5, 12:48 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Billings, Bowman, Burleigh, Dunn, Emmons and 12 more | 7 hr |
| Aug 5, 5:26 PM MDT | Mesoscale Discussion | SPC | Burleigh, Dickey, Eddy, Emmons, Foster, Grant and 10 more | 94 min |
Nearby
Mesoscale Discussions in South Dakota, 2011Mesoscale Discussions in North Dakota, 2011Mesoscale Discussions in Montana, 2011Every mesoscale discussion in 2011
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.