Alert archive / Wisconsin / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 635
The Storm Prediction Center issued this severe thunderstorm watch at Aug 21, 2007, 8:14 PM CDT for 11 counties in Iowa; 10 counties in Minnesota; 12 counties in Wisconsin. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 21, 2007, 8:14 PM CDT (01:14 UTC)
- Expired
- Aug 22, 2007, 3:53 AM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 33 counties
Allamakee County, IA, Buchanan County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Howard County, IA, Mitchell County, IA, Winneshiek County, IA, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Steele County, MN, Wabasha County, MN, Winona County, MN, Adams County, WI, Buffalo County, WI, Clark County, WI, Crawford County, WI, Grant County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Monroe County, WI, Richland County, WI, Trempealeau County, WI, Vernon County, WI
The radar
The La Crosse radar (KARX), 104 km from the middle of the area, began a volume at 01:14 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
- 10%
- Ten or more severe wind reports
- 90%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 8:42 PM CDT | Flash Flood Warning | MPX | Faribault, Freeborn | 3 hr |
| Aug 21, 8:43 PM CDT | Severe Thunderstorm Warning | ARX | Mower | 47 min |
| Aug 21, 9:14 PM CDT | Flash Flood Warning | ARX | Howard, Mitchell | 3 hr |
| Aug 21, 9:50 PM CDT | Severe Thunderstorm Warning | ARX | Floyd | 40 min |
| Aug 21, 9:53 PM CDT | Flash Flood Warning | ARX | Allamakee, Winneshiek | 3 hr |
| Aug 21, 10:15 PM CDT | Severe Thunderstorm Warning | ARX | Chickasaw | 45 min |
| Aug 21, 11:09 PM CDT | Severe Thunderstorm Warning | ARX | Allamakee | 51 min |
| Aug 21, 11:22 PM CDT | Severe Thunderstorm Warning | ARX | Winneshiek | 23 min |
| Aug 21, 11:34 PM CDT | Severe Thunderstorm Warning | ARX | Crawford | 41 min |
| Aug 21, 11:44 PM CDT | Flash Flood Warning | ARX | Vernon | 3 hr |
| Aug 22, 12:01 AM CDT | Severe Thunderstorm Warning | ARX | Grant, Richland | 44 min |
| Aug 22, 12:15 AM CDT | Severe Thunderstorm Warning | ARX | Vernon | 60 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 00:00Z, 1.2 hours before the alert went out and 216 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
- 1298 m above ground
- 0-6 km bulk shear
- 65 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 453 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 21, 10:49 PM CDT | Mesoscale Discussion | SPC | Allamakee, Audubon, Benton, Black Hawk, Boone, Bremer and 37 more | 86 min |
| Aug 22, 2:13 AM CDT | Mesoscale Discussion | SPC | Jackson | 62 min |
| Aug 22, 6:45 AM CDT | Mesoscale Discussion | SPC | Buena Vista, Calhoun, Carroll, Cherokee, Clay, Crawford and 13 more | 60 min |
| Aug 22, 10:12 AM CDT | Mesoscale Discussion | SPC | Buena Vista, Calhoun, Cherokee, Clay, Crawford, Humboldt and 8 more | 93 min |
| Aug 22, 2:37 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 40 more | 83 min |
| Aug 22, 3:20 PM CDT | Severe Thunderstorm Watch | SPC | Fremont, Harrison, Mills, Montgomery, Page, Pottawattamie and 1 more | 6 hr |
| Aug 22, 6:33 PM CDT | Mesoscale Discussion | SPC | Fremont, Harrison, Mills, Montgomery, Page, Pottawattamie and 1 more | 87 min |
| Aug 22, 12:09 AM CDT | Severe Thunderstorm Watch | SPC | Columbia, Dane, Dodge, Fond du Lac, Green, Green Lake and 11 more | 3 hr |
| Aug 22, 3:17 PM CDT | Mesoscale Discussion | SPC | Columbia, Dane, Dodge, Grant, Green, Iowa and 11 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Wisconsin, 2007Severe Thunderstorm Watches in Iowa, 2007Severe Thunderstorm Watches in Minnesota, 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.