Alert archive / Wisconsin / Severe Thunderstorm Watches in 2007

Severe Thunderstorm Watch 587

August 11, 20074 counties in Iowa; Fillmore County, Houston County, Minnesota; 35 counties in Wisconsin

The Storm Prediction Center issued this severe thunderstorm watch at Aug 11, 2007, 9:57 PM CDT for 4 counties in Iowa; Fillmore County, Houston County, Minnesota; 35 counties in Wisconsin. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Aug 11, 2007, 9:57 PM CDT (02:57 UTC)
Expired
Aug 12, 2007, 2:49 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
70 kt
All 41 counties

Allamakee County, IA, Howard County, IA, Mitchell County, IA, Winneshiek County, IA, Fillmore County, MN, Houston County, MN, Adams County, WI, Calumet County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Fond du Lac County, WI, Grant County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jefferson County, WI, Juneau County, WI, Kenosha County, WI, La Crosse County, WI, Lafayette County, WI, Manitowoc County, WI, Marquette County, WI, Milwaukee County, WI, Monroe County, WI, Ozaukee County, WI, Portage County, WI, Racine County, WI, Richland County, WI, Rock County, WI, Sauk County, WI, Sheboygan County, WI, Vernon County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 45 km from the middle of the area, began a volume at 02:58 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
60%
One or more gusts of 65 knots or more
50%
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
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Aug 11, 10:29 PM CDTSevere Thunderstorm WarningARXLa Crosse, Monroe61 min
Aug 11, 10:33 PM CDTSevere Thunderstorm WarningARXFillmore57 min
Aug 11, 11:06 PM CDTSevere Thunderstorm WarningARXHouston39 min
Aug 11, 11:10 PM CDTSevere Thunderstorm WarningARXAdams, Juneau65 min
Aug 11, 11:11 PM CDTSevere Thunderstorm WarningGRBWood49 min
Aug 11, 11:19 PM CDTSevere Thunderstorm WarningMKXSauk71 min
Aug 11, 11:44 PM CDTSevere Thunderstorm WarningMKXColumbia, Green Lake, Marquette76 min
Aug 11, 11:50 PM CDTSevere Thunderstorm WarningGRBPortage, Waushara55 min
Aug 12, 12:17 AM CDTSevere Thunderstorm WarningMKXDane58 min
Aug 12, 12:22 AM CDTSevere Thunderstorm WarningMKXDodge, Fond du Lac68 min
Aug 12, 12:31 AM CDTSevere Thunderstorm WarningMKXIowa49 min
Aug 12, 12:37 AM CDTSevere Thunderstorm WarningMKXDane, Jefferson68 min
Aug 12, 12:46 AM CDTSevere Thunderstorm WarningMKXGreen, Lafayette67 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

Green Bay/Straub, WI (KGRB), launched 00:00Z, 3.0 hours before the alert went out and 213 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, Green Bay/Straub, WI at 00:00Z on 2007-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 261 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, Green Bay/Straub, WI at 00:00Z on 2007-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 78 square meters per square second.193958Sfc1 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
261 J/kg
Mixed-layer CIN
-375 J/kg
Mixed-layer LCL
1182 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 9:43 PM CDTMesoscale DiscussionSPCAllamakee, Bremer, Buchanan, Chickasaw, Clayton, Delaware and 3 more92 min
Aug 11, 11:46 PM CDTMesoscale DiscussionSPCAllamakee, Howard, Mitchell, Winneshiek119 min
Aug 12, 1:20 AM CDTMesoscale DiscussionSPCJackson25 min
Aug 12, 2:52 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Cass, Clarke, Decatur and 12 more83 min
Aug 12, 3:56 PM CDTSevere Thunderstorm WatchSPCAdair, Adams, Appanoose, Audubon, Cass, Clarke and 16 more7 hr
Aug 12, 5:49 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Cass, Dallas, Guthrie and 9 more86 min
Aug 11, 8:45 PM CDTMesoscale DiscussionSPCBlue Earth, Chisago, Dakota, Dodge, Fillmore, Freeborn and 14 more90 min

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.