Alert archive / Minnesota / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 671
The Storm Prediction Center issued this severe thunderstorm watch at Sep 17, 2007, 7:36 PM CDT for 9 counties in Iowa; 50 counties in Minnesota; 10 counties in South Dakota. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 17, 2007, 7:36 PM CDT (00:36 UTC)
- Expired
- Sep 18, 2007, 1:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 69 counties
Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Aitkin County, MN, Anoka County, MN, Benton County, MN, Brown County, MN, Carlton County, MN, Carver County, MN, Cass County, MN, Chippewa County, MN, Chisago County, MN, Cottonwood County, MN, Crow Wing County, MN, Dakota County, MN, Douglas County, MN, Hennepin County, MN, Isanti County, MN, Itasca County, MN, Jackson County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Le Sueur County, MN, Lincoln County, MN, Lyon County, MN, Martin County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Murray County, MN, Nicollet County, MN, Nobles County, MN, Pine County, MN, Pipestone County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rock County, MN, Saint Louis County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Washington County, MN, Watonwan County, MN, Wright County, MN, Yellow Medicine County, MN, Brookings County, SD, Clay County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Minnehaha County, SD, Moody County, SD, Turner County, SD, Union County, SD, Yankton County, SD
The radar
The Minneapolis radar (KMPX), 126 km from the middle of the area, began a volume at 00:37 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
- 40%
- 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
- 20%
- Six or more combined severe hail and wind reports
- 90%
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 |
|---|---|---|---|---|
| Sep 17, 8:26 PM CDT | Severe Thunderstorm Warning | DLH | Cass | 49 min |
| Sep 17, 8:27 PM CDT | Severe Thunderstorm Warning | MPX | Morrison | 28 min |
| Sep 17, 8:31 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa, Lac qui Parle | 21 min |
| Sep 17, 9:07 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa | 38 min |
| Sep 17, 9:16 PM CDT | Severe Thunderstorm Warning | MPX | Morrison, Stearns | 32 min |
| Sep 17, 9:25 PM CDT | Severe Thunderstorm Warning | FSD | McCook, Minnehaha | 19 min |
| Sep 17, 10:21 PM CDT | Severe Thunderstorm Warning | DLH | Cass, Crow Wing | 39 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, 0.6 hours before the alert went out and 124 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
- 1285 J/kg
- Mixed-layer CIN
- -42 J/kg
- Mixed-layer LCL
- 1974 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 225 m²/s²
- 0-3 km storm-relative helicity
- 372 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 3.9
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 17, 10:03 PM CDT | Mesoscale Discussion | SPC | Buena Vista, Cherokee, Clay, Dickinson, Lyon, O'Brien and 3 more | 57 min |
| Sep 18, 3:43 PM CDT | Mesoscale Discussion | SPC | Appanoose, Benton, Cedar, Clarke, Davis, Decatur and 20 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Minnesota, 2007Severe Thunderstorm Watches in South Dakota, 2007Severe Thunderstorm Watches in Iowa, 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.