Alert archive / Minnesota / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 709
The Storm Prediction Center issued this severe thunderstorm watch at Aug 1, 2011, 11:52 AM CDT for 49 counties in Minnesota; 10 counties in North Dakota; 4 counties in South Dakota. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 1, 2011, 11:52 AM CDT (16:52 UTC)
- Expired
- Aug 1, 2011, 7:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 63 counties
Anoka County, MN, Becker County, MN, Benton County, MN, Big Stone County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Clay County, MN, Dakota County, MN, Douglas County, MN, Goodhue County, MN, Grant County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Le Sueur County, MN, Mahnomen County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Nicollet County, MN, Norman County, MN, Otter Tail County, MN, Polk County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Steele County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Traverse County, MN, Wadena County, MN, Waseca County, MN, Washington County, MN, Wilkin County, MN, Wright County, MN, Yellow Medicine County, MN, Barnes County, ND, Cass County, ND, Grand Forks County, ND, Griggs County, ND, Nelson County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Steele County, ND, Traill County, ND, Day County, SD, Grant County, SD, Marshall County, SD, Roberts County, SD
The radar
The Fargo/Grand Forks radar (KMVX), 186 km from the middle of the area, began a volume at 16:53 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
- 30%
- 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
- 40%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
7 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 11:53 AM CDT | Severe Thunderstorm Warning | MPX | Sherburne, Stearns, Wright | 67 min |
| Aug 1, 12:03 PM CDT | Severe Thunderstorm Warning | MPX | Carver, McLeod, Meeker, Renville, Sibley | 57 min |
| Aug 1, 12:45 PM CDT | Severe Thunderstorm Warning | MPX | Carver, Hennepin | 45 min |
| Aug 1, 1:18 PM CDT | Severe Thunderstorm Warning | MPX | Dakota, Le Sueur, Rice, Scott, Sibley | 57 min |
| Aug 1, 1:25 PM CDT | Severe Thunderstorm Warning | MPX | Dakota, Hennepin, Ramsey, Washington | 65 min |
| Aug 1, 2:02 PM CDT | Severe Thunderstorm Warning | MPX | Goodhue, Le Sueur, Rice, Steele, Waseca | 58 min |
| Aug 1, 3:04 PM CDT | Severe Thunderstorm Warning | MPX | Goodhue | 37 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
Minneapolis, MN (KMPX), launched 12:00Z, 4.9 hours before the alert went out and 230 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
- 2974 J/kg
- Mixed-layer CIN
- -122 J/kg
- Mixed-layer LCL
- 898 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 10 m²/s²
- 0-3 km storm-relative helicity
- 59 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.5
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 1:50 PM CDT | Mesoscale Discussion | SPC | Allamakee, Chickasaw, Clayton, Fayette, Howard, Mitchell and 1 more | 25 min |
| Aug 1, 2:04 PM CDT | Severe Thunderstorm Watch | SPC | Allamakee, Howard, Mitchell, Winneshiek | 5 hr |
| Aug 1, 3:53 PM CDT | Mesoscale Discussion | SPC | Allamakee, Chickasaw, Howard, Mitchell, Winneshiek, Worth | 67 min |
| Jul 31, 10:26 PM CDT | Severe Thunderstorm Watch | SPC | Becker, Clay, Clearwater, Grant, Kittson, Mahnomen and 8 more | 8 hr |
| Aug 1, 12:35 AM CDT | Mesoscale Discussion | SPC | Clay, Norman, Polk | 85 min |
| Aug 1, 2:31 AM CDT | Mesoscale Discussion | SPC | Becker, Cass, Clay, Clearwater, Crow Wing, Douglas and 11 more | 89 min |
| Aug 1, 4:57 AM CDT | Severe Thunderstorm Watch | SPC | Becker, Benton, Big Stone, Brown, Cass, Chippewa and 28 more | 7 hr |
| Aug 1, 7:31 AM CDT | Mesoscale Discussion | SPC | Anoka, Benton, Blue Earth, Brown, Carver, Chippewa and 33 more | 89 min |
| Aug 1, 10:42 AM CDT | Mesoscale Discussion | SPC | Benton, Kandiyohi, Meeker, Mille Lacs, Morrison, Pope and 5 more | 63 min |
| Aug 1, 11:29 AM CDT | Mesoscale Discussion | SPC | Anoka, Benton, Carver, Chisago, Dakota, Hennepin and 8 more | 31 min |
| Jul 31, 8:16 PM CDT | Mesoscale Discussion | SPC | Adams, Grant, Morton, Sioux | 89 min |
| Aug 1, 1:33 PM CDT | Mesoscale Discussion | SPC | Adams, Burleigh, Emmons, Grant, Hettinger, Kidder and 10 more | 57 min |
| Aug 1, 2:19 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Bowman, Burleigh, Emmons, Grant, Hettinger and 10 more | 6 hr |
| Aug 1, 5:57 PM CDT | Mesoscale Discussion | SPC | Adams, Barnes, Benson, Burleigh, Cavalier, Dickey and 23 more | 2 hr |
| Aug 1, 6:10 PM CDT | Mesoscale Discussion | SPC | Adams, Barnes, Benson, Burleigh, Cavalier, Dickey and 23 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Minnesota, 2011Severe 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.