Alert archive / South Dakota / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 348
The Storm Prediction Center issued this severe thunderstorm watch at Aug 23, 2018, 6:01 PM CDT for 7 counties in North Dakota; 13 counties in South Dakota. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 23, 2018, 6:01 PM CDT (23:01 UTC)
- Expired
- Aug 23, 2018, 11:43 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
Counties Dickey County, ND, LaMoure County, ND, Logan County, ND, McIntosh County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Brown County, SD, Campbell County, SD, Day County, SD, Edmunds County, SD, Faulk County, SD, Hand County, SD, Hyde County, SD, Marshall County, SD, McPherson County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Walworth County, SD
The radar
The Aberdeen radar (KABR), 43 km from the middle of the area, began a volume at 23:01 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 6:24 PM CDT | Severe Thunderstorm Warning | ABR | Faulk, Hand, Hyde | 36 min |
| Aug 23, 6:29 PM CDT | Tornado Warning | ABR | Faulk, Hand, Hyde | 31 min |
| Aug 23, 7:08 PM CDT | Severe Thunderstorm Warning | ABR | Hand, Hyde | 52 min |
| Aug 23, 8:37 PM CDT | Severe Thunderstorm Warning | ABR | Dewey, Potter | 23 min |
| Aug 23, 9:01 PM CDT | Severe Thunderstorm Warning | ABR | Brown | 17 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Aberdeen, SD (KABR), launched 12:00Z, 11.0 hours before the alert went out and 96 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
- 895 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 96 m²/s²
- 0-3 km storm-relative helicity
- 223 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 3:32 PM CDT | Mesoscale Discussion | SPC | Butte, Custer, Fall River, Lawrence, Meade, Oglala Lakota and 1 more | 118 min |
| Aug 23, 4:32 PM CDT | Mesoscale Discussion | SPC | Brule, Buffalo, Edmunds, Faulk, Hand, Hughes and 6 more | 118 min |
| Aug 23, 6:25 PM CDT | Severe Thunderstorm Watch | SPC | Aurora, Brule, Buffalo, Charles Mix, Douglas, Gregory and 6 more | 3 hr |
| Aug 23, 6:47 PM CDT | Mesoscale Discussion | SPC | Aurora, Brule, Buffalo, Charles Mix, Douglas, Gregory and 6 more | 88 min |
Nearby
Severe Thunderstorm Watches in South Dakota, 2018Severe Thunderstorm Watches in North Dakota, 2018Every severe thunderstorm watch in 2018
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.