Alert archive / South Dakota / Mesoscale Discussions in 2020
Mesoscale Discussion 1289
The Storm Prediction Center issued this mesoscale discussion at Jul 20, 2020, 12:16 PM CDT for 6 counties in North Dakota; 37 counties in South Dakota. It was in force for 119 min.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2020, 12:16 PM CDT (17:16 UTC)
- Expired
- Jul 20, 2020, 2:15 PM CDT
- In force
- 119 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 60%
All 43 counties
Dickey County, ND, Emmons County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Sargent County, ND, Aurora County, SD, Beadle County, SD, Brown County, SD, Brule County, SD, Buffalo County, SD, Campbell County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Day County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Haakon County, SD, Hamlin County, SD, Hand County, SD, Hanson County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Kingsbury County, SD, Lyman County, SD, Marshall County, SD, McPherson County, SD, Meade County, SD, Miner County, SD, Pennington County, SD, Potter County, SD, Roberts County, SD, Sanborn County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD, Ziebach County, SD
The radar
The Aberdeen radar (KABR), 166 km from the middle of the area, began a volume at 17:19 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, 5.3 hours before the alert went out and 226 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
- 89 J/kg
- Mixed-layer CIN
- -242 J/kg
- Mixed-layer LCL
- 1354 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 79 m²/s²
- 0-3 km storm-relative helicity
- 120 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 |
|---|---|---|---|---|
| Jul 19, 7:48 PM CDT | Mesoscale Discussion | SPC | Custer, Fall River, Lawrence, Oglala Lakota, Pennington | 117 min |
| Jul 20, 1:13 PM CDT | Severe Thunderstorm Watch | SPC | Beadle, Bennett, Brule, Buffalo, Custer, Dewey and 19 more | 6 hr |
| Jul 20, 3:19 PM CDT | Mesoscale Discussion | SPC | Beadle, Bennett, Brule, Buffalo, Custer, Fall River and 17 more | 116 min |
| Jul 20, 6:01 PM CDT | Mesoscale Discussion | SPC | Aurora, Beadle, Bennett, Brule, Buffalo, Clark and 12 more | 89 min |
Nearby
Mesoscale Discussions in South Dakota, 2020Mesoscale Discussions in North Dakota, 2020Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.