Alert archive / South Dakota / Mesoscale Discussions in 2007
Mesoscale Discussion 520
The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2007, 6:48 PM CDT for 6 counties in North Dakota; 33 counties in South Dakota. It was in force for 117 min.
The area
The outline as issued.
The facts
- Issued
- Apr 20, 2007, 6:48 PM CDT (23:48 UTC)
- Expired
- Apr 20, 2007, 8:45 PM CDT
- In force
- 117 min
- Issued by
- the Storm Prediction Center
All 39 counties
Dickey County, ND, LaMoure County, ND, McIntosh County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Aurora County, SD, Beadle County, SD, Bennett County, SD, Brown County, SD, Brule County, SD, Buffalo County, SD, Campbell County, SD, Charles Mix County, SD, Clark County, SD, Day County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Gregory County, SD, Haakon County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Lyman County, SD, Marshall County, SD, McPherson County, SD, Mellette County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Tripp County, SD, Walworth County, SD
The radar
The Aberdeen radar (KABR), 109 km from the middle of the area, began a volume at 23:48 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 nearest sounding before it
Aberdeen, SD (KABR), launched 12:00Z, 11.8 hours before the alert went out and 82 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 991 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 132 m²/s²
- 0-3 km storm-relative helicity
- 287 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 |
|---|---|---|---|---|
| Apr 20, 1:05 PM CDT | Mesoscale Discussion | SPC | Dickey, Emmons, LaMoure, Logan, McIntosh | 55 min |
| Apr 20, 1:26 PM CDT | Severe Thunderstorm Watch | SPC | Dickey, LaMoure, McIntosh, Ransom, Richland, Sargent | 10 hr |
| Apr 20, 3:31 PM CDT | Mesoscale Discussion | SPC | Dickey, LaMoure, McIntosh, Ransom, Richland, Sargent | 119 min |
Nearby
Mesoscale Discussions in South Dakota, 2007Mesoscale Discussions in North Dakota, 2007Every mesoscale discussion in 2007
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.