Alert archive / Minnesota / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 628
The Storm Prediction Center issued this severe thunderstorm watch at Aug 20, 2007, 10:23 PM CDT for 31 counties in Minnesota. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 20, 2007, 10:23 PM CDT (03:23 UTC)
- Expired
- Aug 21, 2007, 2:53 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 31 counties
Anoka County, MN, Blue Earth County, MN, Brown County, MN, Carver County, MN, Chippewa County, MN, Cottonwood County, MN, Dakota County, MN, Faribault County, MN, Freeborn County, MN, Hennepin County, MN, Jackson County, MN, Kandiyohi County, MN, Le Sueur County, MN, Martin County, MN, McLeod County, MN, Meeker County, MN, Murray County, MN, Nicollet County, MN, Nobles County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sibley County, MN, Steele County, MN, Swift County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Wright County, MN
The radar
The Minneapolis radar (KMPX), 83 km from the middle of the area, began a volume at 03:27 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
- 20%
- One or more gusts of 65 knots or more
- 5%
- 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
- 60%
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, 3.4 hours before the alert went out and 81 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
- 62 J/kg
- Mixed-layer CIN
- -345 J/kg
- Mixed-layer LCL
- 520 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 170 m²/s²
- 0-3 km storm-relative helicity
- 271 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 7:03 PM CDT | Mesoscale Discussion | SPC | Nobles, Rock | 117 min |
| Aug 21, 2:16 AM CDT | Mesoscale Discussion | SPC | Anoka, Carver, Dakota, Hennepin, Isanti, McLeod and 6 more | 59 min |
| Aug 21, 4:50 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Brown, Cottonwood, Dakota, Dodge, Faribault and 17 more | 85 min |
Nearby
Severe 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.