Alert archive / South Dakota / Severe Thunderstorm Watches in 2018
Severe Thunderstorm Watch 259
The Storm Prediction Center issued this severe thunderstorm watch at Jul 3, 2018, 4:42 PM MDT for Carter County, Montana; 13 counties in South Dakota; 4 counties in Wyoming. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 3, 2018, 4:42 PM MDT (22:42 UTC)
- Expired
- Jul 4, 2018, 12:00 AM MDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
Counties Carter County, MT, Bennett County, SD, Butte County, SD, Custer County, SD, Fall River County, SD, Haakon County, SD, Harding County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Ziebach County, SD, Campbell County, WY, Crook County, WY, Niobrara County, WY, Weston County, WY
The radar
The Rapid City radar (KUDX), 73 km from the middle of the area, began a volume at 22:42 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
- 40%
- 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
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
13 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 3, 6:01 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Fall River, Pennington | 59 min |
| Jul 3, 6:34 PM MDT | Severe Thunderstorm Warning | UNR | Butte, Lawrence | 24 min |
| Jul 3, 8:23 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Pennington | 67 min |
| Jul 3, 8:32 PM MDT | Severe Thunderstorm Warning | UNR | Butte, Lawrence, Meade | 47 min |
| Jul 3, 8:50 PM MDT | Severe Thunderstorm Warning | UNR | Harding, Perkins | 25 min |
| Jul 3, 9:18 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Meade, Oglala Lakota, Pennington | 57 min |
| Jul 3, 9:53 PM MDT | Severe Thunderstorm Warning | UNR | Meade | 22 min |
| Jul 3, 10:13 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Meade, Pennington | 47 min |
| Jul 3, 10:48 PM MDT | Severe Thunderstorm Warning | UNR | Haakon, Meade, Pennington, Ziebach | 72 min |
| Jul 3, 11:01 PM MDT | Tornado Warning | UNR | Haakon, Ziebach | 14 min |
| Jul 3, 11:23 PM MDT | Severe Thunderstorm Warning | UNR | Ziebach | 51 min |
| Jul 3, 11:29 PM MDT | Tornado Warning | UNR | Ziebach | 31 min |
| Jul 3, 11:55 PM MDT | Severe Thunderstorm Warning | UNR | Ziebach | 18 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
Rapid City, SD (KRAP), launched 12:00Z, 10.7 hours before the alert went out and 79 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
- 114 J/kg
- Mixed-layer CIN
- -531 J/kg
- Mixed-layer LCL
- 2085 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 18 m²/s²
- 0-3 km storm-relative helicity
- 145 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 |
|---|---|---|---|---|
| Jul 2, 6:59 PM MDT | Severe Thunderstorm Watch | SPC | Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 2 more | 6 hr |
| Jul 2, 8:50 PM MDT | Mesoscale Discussion | SPC | Big Horn, Carter, Custer, Fallon, Powder River, Rosebud and 2 more | 115 min |
| Jul 2, 11:01 PM MDT | Mesoscale Discussion | SPC | Carter, Custer, Fallon, Powder River | 89 min |
| Jul 3, 2:25 PM MDT | Mesoscale Discussion | SPC | Big Horn, Carter, Powder River | 2 hr |
| Jul 2, 6:36 PM MDT | Severe Thunderstorm Watch | SPC | Brown, Campbell, Clark, Codington, Corson, Day and 11 more | 9 hr |
| Jul 2, 10:32 PM MDT | Mesoscale Discussion | SPC | Clark, Codington, Deuel, Grant, Hamlin, Roberts and 1 more | 88 min |
| Jul 3, 12:59 AM MDT | Severe Thunderstorm Watch | SPC | Brown, Campbell, Clark, Codington, Corson, Day and 11 more | 7 hr |
| Jul 3, 3:15 AM MDT | Mesoscale Discussion | SPC | Brown, Campbell, Clark, Codington, Corson, Day and 10 more | 90 min |
| Jul 3, 6:01 AM MDT | Mesoscale Discussion | SPC | Brown, Campbell, McPherson, Marshall, Roberts | 119 min |
| Jul 3, 5:16 PM MDT | Mesoscale Discussion | SPC | Beadle, Brookings, Brown, Campbell, Clark, Codington and 17 more | 2 hr |
| Jul 3, 5:42 PM MDT | Severe Thunderstorm Watch | SPC | Brown, Clark, Day, Edmunds, Faulk, Hand and 8 more | 4 hr |
Nearby
Severe Thunderstorm Watches in South Dakota, 2018Severe Thunderstorm Watches in Wyoming, 2018Severe Thunderstorm Watches in Montana, 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.