Alert archive / Minnesota / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 646
The Storm Prediction Center issued this severe thunderstorm watch at Jul 15, 2011, 2:56 AM CDT for 14 counties in Minnesota; 12 counties in North Dakota. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 15, 2011, 2:56 AM CDT (07:56 UTC)
- Expired
- Jul 15, 2011, 10:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 26 counties
Becker County, MN, Beltrami County, MN, Clay County, MN, Clearwater County, MN, Hubbard County, MN, Mahnomen County, MN, Marshall County, MN, Norman County, MN, Otter Tail County, MN, Pennington County, MN, Polk County, MN, Red Lake County, MN, Wadena County, MN, Wilkin County, MN, Barnes County, ND, Cass County, ND, Grand Forks County, ND, Griggs County, ND, Nelson County, ND, Ramsey County, ND, Ransom County, ND, Richland County, ND, Sargent County, ND, Steele County, ND, Traill County, ND, Walsh County, ND
The radar
The Fargo/Grand Forks radar (KMVX), 30 km from the middle of the area, began a volume at 08:00 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
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 15, 3:25 AM CDT | Tornado Warning | FGF | Barnes | 50 min |
| Jul 15, 3:53 AM CDT | Severe Thunderstorm Warning | FGF | Ransom, Richland | 52 min |
| Jul 15, 4:04 AM CDT | Severe Thunderstorm Warning | FGF | Barnes, Cass | 56 min |
| Jul 15, 4:18 AM CDT | Tornado Warning | FGF | Ransom, Richland | 42 min |
| Jul 15, 4:50 AM CDT | Severe Thunderstorm Warning | FGF | Otter Tail, Wilkin | 55 min |
| Jul 15, 5:00 AM CDT | Severe Thunderstorm Warning | FGF | Clay, Norman | 43 min |
| Jul 15, 5:12 AM CDT | Tornado Warning | FGF | Wilkin | 39 min |
| Jul 15, 5:47 AM CDT | Severe Thunderstorm Warning | FGF | Grant, Otter Tail, Wilkin | 58 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 00:00Z, 7.9 hours before the alert went out and 289 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
- 2132 J/kg
- Mixed-layer CIN
- -66 J/kg
- Mixed-layer LCL
- 698 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 101 m²/s²
- 0-3 km storm-relative helicity
- 76 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 3.2
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 15, 6:30 AM CDT | Mesoscale Discussion | SPC | Benton, Carver, Clay, Douglas, Grant, Hennepin and 14 more | 2 hr |
| Jul 15, 6:40 AM CDT | Severe Thunderstorm Watch | SPC | Anoka, Benton, Carver, Chisago, Douglas, Hennepin and 14 more | 6 hr |
| Jul 15, 11:20 AM CDT | Mesoscale Discussion | SPC | Anoka, Blue Earth, Brown, Carver, Chippewa, Dakota and 30 more | 85 min |
| Jul 15, 2:21 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 6 more | 114 min |
| Jul 15, 6:10 PM CDT | Mesoscale Discussion | SPC | Becker, Beltrami, Clay, Clearwater, Grant, Hubbard and 8 more | 65 min |
| Jul 14, 9:46 PM CDT | Mesoscale Discussion | SPC | Adams, Emmons, Grant, Kidder, Logan, McIntosh and 1 more | 59 min |
| Jul 14, 11:01 PM CDT | Severe Thunderstorm Watch | SPC | Adams, Billings, Bowman, Burke, Divide, Dunn and 14 more | 6 hr |
| Jul 14, 11:55 PM CDT | Mesoscale Discussion | SPC | Barnes, Cass, Dickey, Emmons, Kidder, LaMoure and 6 more | 65 min |
| Jul 15, 2:54 AM CDT | Mesoscale Discussion | SPC | Adams, Billings, Bottineau, Bowman, Burke, Divide and 12 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Minnesota, 2011Severe Thunderstorm Watches in North 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.