Alert archive / South Dakota / Mesoscale Discussions in 2017
Mesoscale Discussion 1420
The Storm Prediction Center issued this mesoscale discussion at Jul 25, 2017, 2:41 PM CDT for 4 counties in Nebraska; 32 counties in South Dakota. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2017, 2:41 PM CDT (19:41 UTC)
- Expired
- Jul 25, 2017, 4:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 95%
All 36 counties
Boyd County, NE, Cherry County, NE, Keya Paha County, NE, Sheridan County, NE, Aurora County, SD, Beadle County, SD, Bennett County, SD, Brookings County, SD, Brule County, SD, Buffalo County, SD, Charles Mix County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Deuel County, SD, Douglas County, SD, Grant County, SD, Gregory County, SD, Hamlin County, SD, Hand County, SD, Hanson County, SD, Hughes County, SD, Hutchinson County, SD, Hyde County, SD, Jerauld County, SD, Jones County, SD, Kingsbury County, SD, Lake County, SD, Lyman County, SD, McCook County, SD, Mellette County, SD, Miner County, SD, Sanborn County, SD, Spink County, SD, Todd County, SD, Tripp County, SD
The radar
The North Platte radar (KLNX), 182 km from the middle of the area, began a volume at 19:41 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
Aberdeen, SD (KABR), launched 12:00Z, 7.7 hours before the alert went out and 193 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
- 853 J/kg
- Mixed-layer CIN
- -568 J/kg
- Mixed-layer LCL
- 1011 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 234 m²/s²
- 0-3 km storm-relative helicity
- 238 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 25, 3:22 PM CDT | Severe Thunderstorm Watch | SPC | Brown, Cherry, Grant, Hooker, Keya Paha, Sheridan and 1 more | 8 hr |
| Jul 25, 6:25 PM CDT | Mesoscale Discussion | SPC | Boyd, Brown, Cherry, Grant, Hooker, Keya Paha and 1 more | 95 min |
Nearby
Mesoscale Discussions in South Dakota, 2017Mesoscale Discussions in Nebraska, 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.