Alert archive / South Dakota / Severe Thunderstorm Watches in 2007

Severe Thunderstorm Watch 433

June 21, 200711 counties in Iowa; 8 counties in Minnesota; 24 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Jun 21, 2007, 9:38 AM CDT for 11 counties in Iowa; 8 counties in Minnesota; 24 counties in South Dakota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Jun 21, 2007, 9:38 AM CDT (14:38 UTC)
Expired: Jun 21, 2007, 4:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 60 kt

All 43 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Charles Mix County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 69 km from the middle of the area, began a volume at 14:40 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: 50%
One or more gusts of 65 knots or more: 40%
Ten or more severe hail reports: 50%
One or more hailstones of 2 inches or more: 50%
Six or more combined severe hail and wind reports: 90%

Warnings issued inside it

10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jun 21, 10:15 AM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule	60 min
Jun 21, 10:42 AM CDT	Severe Thunderstorm Warning	FSD	Douglas	53 min
Jun 21, 11:12 AM CDT	Severe Thunderstorm Warning	FSD	McCook, Miner	48 min
Jun 21, 11:15 AM CDT	Severe Thunderstorm Warning	FSD	Aurora	15 min
Jun 21, 11:57 AM CDT	Severe Thunderstorm Warning	FSD	McCook, Minnehaha	48 min
Jun 21, 12:08 PM CDT	Severe Thunderstorm Warning	FSD	Lincoln, Turner	52 min
Jun 21, 12:14 PM CDT	Severe Thunderstorm Warning	FSD	Minnehaha	46 min
Jun 21, 12:54 PM CDT	Severe Thunderstorm Warning	FSD	Lincoln	51 min
Jun 21, 1:18 PM CDT	Severe Thunderstorm Warning	FSD	Union	42 min
Jun 21, 1:26 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Sioux	34 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 20, 11:30 PM CDT	Mesoscale Discussion	SPC	Howard, Mitchell, Winnebago, Worth	90 min
Jun 21, 4:27 AM CDT	Severe Thunderstorm Watch	SPC	Allamakee, Howard, Mitchell, Winneshiek	8 hr
Jun 21, 9:10 AM CDT	Mesoscale Discussion	SPC	Clay, Dickinson, Lyon, O'Brien, Osceola, Sioux	35 min
Jun 21, 9:57 AM CDT	Mesoscale Discussion	SPC	Allamakee, Cedar, Clayton, Clinton, Delaware, Des Moines and 10 more	33 min
Jun 21, 11:55 AM CDT	Mesoscale Discussion	SPC	Allamakee, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 16 more	50 min
Jun 21, 11:59 AM CDT	Severe Thunderstorm Watch	SPC	Allamakee, Benton, Black Hawk, Boone, Bremer, Buchanan and 36 more	8 hr
Jun 21, 2:13 PM CDT	Mesoscale Discussion	SPC	Allamakee, Benton, Black Hawk, Boone, Bremer, Buchanan and 50 more	62 min
Jun 21, 3:15 PM CDT	Mesoscale Discussion	SPC	Cherokee, Clay, Dickinson, Ida, Lyon, O'Brien and 4 more	30 min
Jun 21, 3:25 PM CDT	Mesoscale Discussion	SPC	Adair, Allamakee, Audubon, Benton, Black Hawk, Boone and 52 more	35 min
Jun 21, 3:55 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Audubon, Cass, Cedar, Clarke and 26 more	3 hr
Jun 21, 5:42 PM CDT	Mesoscale Discussion	SPC	Allamakee, Benton, Black Hawk, Bremer, Buchanan, Cedar and 25 more	93 min
Jun 21, 6:47 PM CDT	Severe Thunderstorm Watch	SPC	Appanoose, Cedar, Clayton, Clinton, Davis, Delaware and 18 more	4 hr
Jun 20, 8:28 PM CDT	Mesoscale Discussion	SPC	Blue Earth, Dodge, Goodhue, Le Sueur, Olmsted, Rice and 2 more	92 min
Jun 21, 2:10 AM CDT	Mesoscale Discussion	SPC	Big Stone, Lac qui Parle, Stevens, Traverse, Yellow Medicine	95 min
Jun 21, 2:29 AM CDT	Severe Thunderstorm Watch	SPC	Big Stone, Traverse, Wilkin	8 hr
Jun 21, 3:55 AM CDT	Mesoscale Discussion	SPC	Big Stone, Blue Earth, Brown, Carver, Chippewa, Cottonwood and 32 more	95 min
Jun 21, 7:14 AM CDT	Mesoscale Discussion	SPC	Blue Earth, Brown, Chippewa, Cottonwood, Faribault, Jackson and 11 more	91 min
Jun 21, 11:08 AM CDT	Mesoscale Discussion	SPC	Anoka, Benton, Brown, Carver, Chippewa, Dakota and 25 more	67 min
Jun 21, 5:34 AM CDT	Mesoscale Discussion	SPC	Brown, Campbell, Clark, Codington, Corson, Day and 10 more	86 min
Jun 21, 2:43 PM CDT	Mesoscale Discussion	SPC	Corson, Dewey, Harding, Meade, Perkins, Ziebach	92 min
Jun 21, 4:37 PM CDT	Tornado Watch	SPC	Bennett, Butte, Custer, Dewey, Fall River, Haakon and 12 more	7 hr

Nearby

Severe Thunderstorm Watches in South Dakota, 2007 Severe Thunderstorm Watches in Iowa, 2007 Severe Thunderstorm Watches in Minnesota, 2007 Every 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; radar from the NEXRAD Level II archive.