Alert archive / North Dakota / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 729
The Storm Prediction Center issued this severe thunderstorm watch at Aug 5, 2011, 12:48 PM MDT for 18 counties in North Dakota; 13 counties in South Dakota. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 5, 2011, 12:48 PM MDT (18:48 UTC)
- Expired
- Aug 5, 2011, 8:00 PM MDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 31 counties
Adams County, ND, Billings County, ND, Bowman County, ND, Burleigh County, ND, Dunn County, ND, Emmons County, ND, Golden Valley County, ND, Grant County, ND, Hettinger County, ND, McKenzie County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Oliver County, ND, Sheridan County, ND, Sioux County, ND, Slope County, ND, Stark County, ND, Bennett County, SD, Butte County, SD, Campbell County, SD, Corson County, SD, Dewey County, SD, Haakon County, SD, Harding County, SD, Jackson County, SD, Lawrence County, SD, Meade County, SD, Pennington County, SD, Perkins County, SD, Ziebach County, SD
The radar
The Bismarck radar (KBIS), 87 km from the middle of the area, began a volume at 18:51 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
36 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 5, 1:15 PM MDT | Severe Thunderstorm Warning | UNR | Butte, Harding | 75 min |
| Aug 5, 1:19 PM MDT | Severe Thunderstorm Warning | BIS | Bowman, Slope | 56 min |
| Aug 5, 1:23 PM MDT | Severe Thunderstorm Warning | UNR | Harding | 67 min |
| Aug 5, 1:26 PM MDT | Severe Thunderstorm Warning | BIS | Billings, Golden Valley | 29 min |
| Aug 5, 1:55 PM MDT | Severe Thunderstorm Warning | UNR | Butte | 65 min |
| Aug 5, 2:18 PM MDT | Flash Flood Warning | BIS | Billings, Dunn, Stark | 6 hr |
| Aug 5, 2:44 PM MDT | Flash Flood Warning | BIS | Billings, Golden Valley, Slope | 2 hr |
| Aug 5, 2:51 PM MDT | Severe Thunderstorm Warning | BIS | Dunn, Stark | 54 min |
| Aug 5, 2:58 PM MDT | Severe Thunderstorm Warning | UNR | Butte, Meade | 62 min |
| Aug 5, 3:13 PM MDT | Severe Thunderstorm Warning | BIS | Bowman | 47 min |
| Aug 5, 3:45 PM MDT | Severe Thunderstorm Warning | BIS | Dunn, Stark | 60 min |
| Aug 5, 3:52 PM MDT | Severe Thunderstorm Warning | UNR | Butte, Meade | 53 min |
| Aug 5, 3:56 PM MDT | Severe Thunderstorm Warning | UNR | Meade | 64 min |
| Aug 5, 3:59 PM MDT | Flash Flood Warning | BIS | Stark | 6 hr |
| Aug 5, 4:23 PM MDT | Severe Thunderstorm Warning | BIS | Grant, Hettinger, Mercer, Morton, Oliver, Stark | 67 min |
| Aug 5, 4:31 PM MDT | Severe Thunderstorm Warning | UNR | Custer, Pennington | 59 min |
| Aug 5, 4:34 PM MDT | Tornado Warning | BIS | Morton | 26 min |
| Aug 5, 4:44 PM MDT | Severe Thunderstorm Warning | UNR | Meade | 61 min |
| Aug 5, 4:48 PM MDT | Severe Thunderstorm Warning | UNR | Perkins, Ziebach | 72 min |
| Aug 5, 5:03 PM MDT | Severe Thunderstorm Warning | ABR | Corson, Dewey | 57 min |
| Aug 5, 5:04 PM MDT | Severe Thunderstorm Warning | BIS | Grant, Morton, Oliver | 41 min |
| Aug 5, 5:07 PM MDT | Severe Thunderstorm Warning | UNR | Custer | 53 min |
| Aug 5, 5:19 PM MDT | Severe Thunderstorm Warning | BIS | Grant, Morton | 39 min |
| Aug 5, 5:24 PM MDT | Severe Thunderstorm Warning | UNR | Meade, Pennington | 66 min |
| Aug 5, 5:43 PM MDT | Severe Thunderstorm Warning | BIS | Burleigh, Emmons, Morton, Oliver | 62 min |
| Aug 5, 5:56 PM MDT | Severe Thunderstorm Warning | UNR | Pennington | 64 min |
| Aug 5, 5:59 PM MDT | Severe Thunderstorm Warning | ABR | Corson, Dewey | 61 min |
| Aug 5, 6:12 PM MDT | Severe Thunderstorm Warning | ABR | Dewey | 48 min |
| Aug 5, 6:13 PM MDT | Severe Thunderstorm Warning | UNR | Haakon, Pennington | 62 min |
| Aug 5, 6:23 PM MDT | Severe Thunderstorm Warning | UNR | Haakon, Ziebach | 67 min |
| Aug 5, 6:45 PM MDT | Severe Thunderstorm Warning | BIS | Burleigh, Emmons, Kidder | 30 min |
| Aug 5, 6:48 PM MDT | Severe Thunderstorm Warning | ABR | Campbell, Corson | 42 min |
| Aug 5, 6:52 PM MDT | Severe Thunderstorm Warning | UNR | Bennett, Jackson | 53 min |
| Aug 5, 7:00 PM MDT | Severe Thunderstorm Warning | ABR | Dewey, Potter, Stanley, Sully | 60 min |
| Aug 5, 7:05 PM MDT | Severe Thunderstorm Warning | UNR | Harding | 55 min |
| Aug 5, 7:30 PM MDT | Severe Thunderstorm Warning | ABR | Dewey, Hughes, Jones, Lyman, Stanley, Sully | 46 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
Bismarck Municip, ND (KBIS), launched 12:00Z, 6.8 hours before the alert went out and 92 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
- 825 J/kg
- Mixed-layer CIN
- -179 J/kg
- Mixed-layer LCL
- 1272 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 87 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 4, 6:40 PM MDT | Mesoscale Discussion | SPC | Adams, Billings, Bowman, Dunn, Golden Valley, Hettinger and 2 more | 95 min |
| Aug 5, 12:05 PM MDT | Mesoscale Discussion | SPC | Adams, Billings, Bowman, Emmons, Golden Valley, Grant and 5 more | 2 hr |
| Aug 5, 4:25 PM MDT | Mesoscale Discussion | SPC | Adams, Billings, Bowman, Burleigh, Dunn, Golden Valley and 9 more | 2 hr |
| Aug 5, 5:26 PM MDT | Mesoscale Discussion | SPC | Burleigh, Dickey, Eddy, Emmons, Foster, Grant and 10 more | 94 min |
Nearby
Severe Thunderstorm Watches in North Dakota, 2011Severe Thunderstorm Watches in South Dakota, 2011Every severe thunderstorm watch in 2011
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.