Alert archive / Minnesota / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 678
The Storm Prediction Center issued this severe thunderstorm watch at Sep 21, 2007, 6:04 AM CDT for Gogebic County, Keweenaw County, Ontonagon County, Michigan; 30 counties in Minnesota; 17 counties in Wisconsin. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 21, 2007, 6:04 AM CDT (11:04 UTC)
- Expired
- Sep 21, 2007, 11:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 60 kt
All 50 counties
Gogebic County, MI, Keweenaw County, MI, Ontonagon County, MI, Aitkin County, MN, Anoka County, MN, Benton County, MN, Carlton County, MN, Carver County, MN, Cass County, MN, Chisago County, MN, Cook County, MN, Crow Wing County, MN, Dakota County, MN, Hennepin County, MN, Isanti County, MN, Itasca County, MN, Kanabec County, MN, Kandiyohi County, MN, Lake County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Pine County, MN, Ramsey County, MN, Renville County, MN, Saint Louis County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Washington County, MN, Wright County, MN, Ashland County, WI, Barron County, WI, Bayfield County, WI, Burnett County, WI, Chippewa County, WI, Douglas County, WI, Dunn County, WI, Iron County, WI, Oneida County, WI, Pierce County, WI, Polk County, WI, Price County, WI, Rusk County, WI, Saint Croix County, WI, Sawyer County, WI, Vilas County, WI, Washburn County, WI
The radar
The Duluth radar (KDLH), 21 km from the middle of the area, began a volume at 11:05 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
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 10%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 40%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 6:09 AM CDT | Severe Thunderstorm Warning | DLH | Ashland, Bayfield | 36 min |
| Sep 21, 6:13 AM CDT | Severe Thunderstorm Warning | MPX | Anoka, Isanti | 22 min |
| Sep 21, 6:33 AM CDT | Severe Thunderstorm Warning | DLH | Saint Louis | 29 min |
| Sep 21, 6:41 AM CDT | Severe Thunderstorm Warning | DLH | Burnett, Washburn | 49 min |
| Sep 21, 6:56 AM CDT | Severe Thunderstorm Warning | DLH | Pine | 35 min |
| Sep 21, 7:04 AM CDT | Severe Thunderstorm Warning | DLH | Douglas | 30 min |
| Sep 21, 7:22 AM CDT | Severe Thunderstorm Warning | DLH | Saint Louis | 23 min |
| Sep 21, 7:23 AM CDT | Severe Thunderstorm Warning | DLH | Iron | 21 min |
| Sep 21, 7:37 AM CDT | Severe Thunderstorm Warning | DLH | Ashland, Iron | 38 min |
| Sep 21, 7:43 AM CDT | Severe Thunderstorm Warning | DLH | Lake, Saint Louis | 13 min |
| Sep 21, 7:43 AM CDT | Severe Thunderstorm Warning | DLH | Lake, Saint Louis | 13 min |
| Sep 21, 7:50 AM CDT | Severe Thunderstorm Warning | DLH | Lake, Saint Louis | 7 min |
| Sep 21, 7:59 AM CDT | Severe Thunderstorm Warning | DLH | Lake | 26 min |
| Sep 21, 8:20 AM CDT | Severe Thunderstorm Warning | DLH | Aitkin | 25 min |
| Sep 21, 9:23 AM CDT | Severe Thunderstorm Warning | DLH | Koochiching, Saint Louis | 31 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
International Fa, MN (KINL), launched 00:00Z, 11.1 hours before the alert went out and 219 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 757 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 555 m²/s²
- 0-3 km storm-relative helicity
- 616 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.7
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 10:24 AM CDT | Mesoscale Discussion | SPC | Menominee | 66 min |
| Sep 21, 1:34 PM CDT | Mesoscale Discussion | SPC | Baraga, Gogebic, Houghton, Iron, Ontonagon | 116 min |
| Sep 21, 2:46 PM CDT | Tornado Watch | SPC | Baraga, Dickinson, Gogebic, Houghton, Iron, Keweenaw and 3 more | 8 hr |
| Sep 21, 6:49 PM CDT | Mesoscale Discussion | SPC | Alger, Delta, Leelanau, Luce, Mackinac, Menominee and 1 more | 86 min |
| Sep 20, 8:40 PM CDT | Mesoscale Discussion | SPC | Murray, Nobles, Pipestone, Rock | 95 min |
| Sep 20, 11:13 PM CDT | Severe Thunderstorm Watch | SPC | Aitkin, Carlton, Cass, Cook, Crow Wing, Itasca and 4 more | 7 hr |
| Sep 21, 12:00 AM CDT | Tornado Watch | SPC | Becker, Beltrami, Benton, Big Stone, Chippewa, Clay and 28 more | 6 hr |
| Sep 21, 3:08 AM CDT | Mesoscale Discussion | SPC | Aitkin, Carlton, Cook, Itasca, Koochiching, Lake and 2 more | 2 hr |
| Sep 21, 3:29 AM CDT | Mesoscale Discussion | SPC | Becker, Beltrami, Benton, Big Stone, Chippewa, Clay and 27 more | 2 hr |
| Sep 21, 3:17 PM CDT | Mesoscale Discussion | SPC | Houston | 88 min |
| Sep 21, 3:53 PM CDT | Severe Thunderstorm Watch | SPC | Houston | 4 hr |
| Sep 20, 11:09 PM CDT | Mesoscale Discussion | SPC | Barron, Burnett, Chippewa, Clark, Dunn, Eau Claire and 9 more | 81 min |
| Sep 21, 6:17 PM CDT | Mesoscale Discussion | SPC | Columbia, Dane, Dodge, Grant, Green, Iowa and 7 more | 88 min |
Nearby
Severe Thunderstorm Watches in Minnesota, 2007Severe Thunderstorm Watches in Wisconsin, 2007Severe Thunderstorm Watches in Michigan, 2007Every severe thunderstorm watch in 2007
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.