Alert archive / South Dakota / Mesoscale Discussions in 2017
Mesoscale Discussion 1575
The Storm Prediction Center issued this mesoscale discussion at Aug 26, 2017, 1:13 PM MDT for 9 counties in Nebraska; Sioux County, North Dakota; 14 counties in South Dakota. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 26, 2017, 1:13 PM MDT (19:13 UTC)
- Expired
- Aug 26, 2017, 3:45 PM MDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 24 counties
Sioux County, ND, Arthur County, NE, Box Butte County, NE, Cherry County, NE, Dawes County, NE, Garden County, NE, Grant County, NE, Hooker County, NE, Morrill County, NE, Sheridan County, NE, Bennett County, SD, Corson County, SD, Dewey County, SD, Haakon County, SD, Jackson County, SD, Jones County, SD, Meade County, SD, Mellette County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Stanley County, SD, Todd County, SD, Ziebach County, SD
The radar
The Rapid City radar (KUDX), 139 km from the middle of the area, began a volume at 19:14 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 (KRAP), launched 12:00Z, 7.2 hours before the alert went out and 137 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
- 69 J/kg
- Mixed-layer CIN
- -227 J/kg
- Mixed-layer LCL
- 2080 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 55 m²/s²
- 0-3 km storm-relative helicity
- 110 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 26, 2:04 PM MDT | Severe Thunderstorm Watch | SPC | Box Butte, Cherry, Dawes, Garden, Grant, Hooker and 3 more | 7 hr |
| Aug 26, 3:24 PM MDT | Mesoscale Discussion | SPC | Arthur, Blaine, Box Butte, Cherry, Dawes, Garden and 6 more | 2 hr |
| Aug 26, 3:46 PM MDT | Mesoscale Discussion | SPC | Furnas, Hitchcock, Red Willow | 2 hr |
Nearby
Mesoscale Discussions in South Dakota, 2017Mesoscale Discussions in Nebraska, 2017Mesoscale Discussions in North Dakota, 2017Every mesoscale discussion in 2017
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.