Alert archive / South Dakota / Severe Thunderstorm Watches in 2013
Severe Thunderstorm Watch 484
The Storm Prediction Center issued this severe thunderstorm watch at Aug 7, 2013, 5:02 PM MDT for 5 counties in Nebraska; 11 counties in South Dakota; 5 counties in Wyoming. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 7, 2013, 5:02 PM MDT (23:02 UTC)
- Expired
- Aug 7, 2013, 11:00 PM MDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 21 counties
Box Butte County, NE, Cherry County, NE, Dawes County, NE, Sheridan County, NE, Sioux County, NE, Bennett County, SD, Butte County, SD, Custer County, SD, Fall River County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Mellette County, SD, Pennington County, SD, Todd County, SD, Tripp County, SD, Campbell County, WY, Converse County, WY, Crook County, WY, Niobrara County, WY, Weston County, WY
The radar
The Rapid City radar (KUDX), 100 km from the middle of the area, began a volume at 23:02 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
- 2%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
19 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 7, 5:04 PM MDT | Severe Thunderstorm Warning | UNR | Lawrence, Pennington | 41 min |
| Aug 7, 5:11 PM MDT | Severe Thunderstorm Warning | UNR | 64 min | |
| Aug 7, 5:44 PM MDT | Severe Thunderstorm Warning | UNR | Lawrence, Pennington | 46 min |
| Aug 7, 5:47 PM MDT | Severe Thunderstorm Warning | UNR | Crook, Weston | 43 min |
| Aug 7, 6:03 PM MDT | Severe Thunderstorm Warning | UNR | Custer | 42 min |
| Aug 7, 6:05 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 40 min |
| Aug 7, 6:22 PM MDT | Severe Thunderstorm Warning | UNR | Pennington | 38 min |
| Aug 7, 6:34 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 41 min |
| Aug 7, 6:37 PM MDT | Flash Flood Warning | UNR | Weston | 6 hr |
| Aug 7, 7:15 PM MDT | Severe Thunderstorm Warning | UNR | Weston | 60 min |
| Aug 7, 7:20 PM MDT | Severe Thunderstorm Warning | UNR | Butte | 40 min |
| Aug 7, 7:38 PM MDT | Flash Flood Warning | UNR | Fall River | 6 hr |
| Aug 7, 7:59 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Fall River | 61 min |
| Aug 7, 8:13 PM MDT | Severe Thunderstorm Warning | UNR | 62 min | |
| Aug 7, 8:17 PM MDT | Severe Thunderstorm Warning | UNR | Campbell | 58 min |
| Aug 7, 8:27 PM MDT | Severe Thunderstorm Warning | UNR | Fall River | 63 min |
| Aug 7, 8:47 PM MDT | Severe Thunderstorm Warning | UNR | Campbell, Crook | 28 min |
| Aug 7, 8:58 PM MDT | Severe Thunderstorm Warning | UNR | Haakon, Jackson | 62 min |
| Aug 7, 9:20 PM MDT | Severe Thunderstorm Warning | UNR | Fall River | 25 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
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 11.0 hours before the alert went out and 408 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
- 84 J/kg
- Mixed-layer CIN
- -182 J/kg
- Mixed-layer LCL
- 1063 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- -20 m²/s²
- 0-3 km storm-relative helicity
- 25 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 6, 8:37 PM MDT | Mesoscale Discussion | SPC | Burt, Butler, Cass, Colfax, Cuming, Dodge and 11 more | 113 min |
| Aug 6, 9:21 PM MDT | Mesoscale Discussion | SPC | Chase, Dundy, Frontier, Hayes, Hitchcock, Lincoln and 2 more | 84 min |
| Aug 7, 4:13 PM MDT | Mesoscale Discussion | SPC | Arthur, Banner, Box Butte, Cheyenne, Dawes, Deuel and 7 more | 92 min |
Nearby
Severe Thunderstorm Watches in South Dakota, 2013Severe Thunderstorm Watches in Nebraska, 2013Severe Thunderstorm Watches in Wyoming, 2013Every severe thunderstorm watch in 2013
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.