Alert archive / Minnesota / Severe Thunderstorm Watches in 2007

Severe Thunderstorm Watch 585

August 11, 200733 counties in Minnesota

The Storm Prediction Center issued this severe thunderstorm watch at Aug 11, 2007, 1:31 AM CDT for 33 counties in Minnesota. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Aug 11, 2007, 1:31 AM CDT (06:31 UTC)
Expired
Aug 11, 2007, 6:00 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 33 counties

Anoka County, MN, Benton County, MN, Brown County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Dakota County, MN, Goodhue County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, Le Sueur County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Nicollet County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Swift County, MN, Todd County, MN, Washington County, MN, Wright County, MN, Yellow Medicine County, MN

The radar

The Minneapolis radar (KMPX), 80 km from the middle of the area, began a volume at 06:33 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
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Aug 11, 1:34 AM CDTSevere Thunderstorm WarningMPXChippewa, Kandiyohi, Swift56 min
Aug 11, 1:47 AM CDTSevere Thunderstorm WarningMPXMorrison58 min
Aug 11, 1:54 AM CDTSevere Thunderstorm WarningMPXMeeker66 min
Aug 11, 1:57 AM CDTSevere Thunderstorm WarningMPXBenton, Sherburne, Stearns, Wright63 min
Aug 11, 2:01 AM CDTSevere Thunderstorm WarningMPXRenville59 min
Aug 11, 2:33 AM CDTSevere Thunderstorm WarningMPXCarver, McLeod57 min
Aug 11, 2:44 AM CDTSevere Thunderstorm WarningMPXHennepin61 min
Aug 11, 2:53 AM CDTFlash Flood WarningMPXAnoka, Hennepin, Ramsey3 hr
Aug 11, 2:53 AM CDTFlash Flood WarningMPXAnoka, Dakota, Hennepin, Ramsey3 hr
Aug 11, 3:01 AM CDTSevere Thunderstorm WarningMPXWright29 min
Aug 11, 3:07 AM CDTFlash Flood WarningMPXWright113 min
Aug 11, 3:15 AM CDTSevere Thunderstorm WarningMPXSibley44 min
Aug 11, 3:27 AM CDTSevere Thunderstorm WarningMPXDakota, Ramsey, Washington63 min
Aug 11, 3:40 AM CDTFlash Flood WarningMPXScott65 min
Aug 11, 3:51 AM CDTSevere Thunderstorm WarningMPXGoodhue54 min
Aug 11, 4:39 AM CDTSevere Thunderstorm WarningMPXLe Sueur39 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, 6.5 hours before the alert went out and 78 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.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2007-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 639 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2007-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
639 J/kg
Mixed-layer CIN
-156 J/kg
Mixed-layer LCL
1768 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
13 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 12:58 AM CDTMesoscale DiscussionSPCAnoka, Benton, Big Stone, Carver, Chippewa, Chisago and 32 more62 min
Aug 11, 3:00 AM CDTMesoscale DiscussionSPCAnoka, Benton, Blue Earth, Brown, Carver, Chisago and 26 more60 min
Aug 11, 5:15 AM CDTMesoscale DiscussionSPCGoodhue, Le Sueur, Rice, Wabasha, Winona30 min
Aug 11, 3:01 PM CDTMesoscale DiscussionSPCBlue Earth, Brown, Carver, Chippewa, Cottonwood, Dakota and 33 more89 min
Aug 11, 6:21 PM CDTSevere Thunderstorm WatchSPCAitkin, Anoka, Blue Earth, Brown, Carlton, Carver and 27 more6 hr
Aug 11, 6:31 PM CDTMesoscale DiscussionSPCCook, Lake119 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.