Alert archive / Wisconsin / Severe Thunderstorm Watches in 2018

Severe Thunderstorm Watch 276

July 13, 20189 counties in Iowa; Fillmore County, Houston County, Minnesota; 32 counties in Wisconsin

The Storm Prediction Center issued this severe thunderstorm watch at Jul 13, 2018, 3:54 PM CDT for 9 counties in Iowa; Fillmore County, Houston County, Minnesota; 32 counties in Wisconsin. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 13, 2018, 3:54 PM CDT (20:54 UTC)
Expired
Jul 13, 2018, 9:54 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
55 kt
All 43 counties

Allamakee County, IA, Buchanan County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Dubuque County, IA, Fayette County, IA, Howard 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, 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, Waushara County, WI, Winnebago County, WI

The radar

The La Crosse radar (KARX), 73 km from the middle of the area, began a volume at 20:57 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
10%
Ten or more severe hail reports
20%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
50%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 13, 3:57 PM CDTSevere Thunderstorm WarningARXHoward48 min
Jul 13, 4:22 PM CDTSevere Thunderstorm WarningARXWinneshiek53 min
Jul 13, 4:36 PM CDTSevere Thunderstorm WarningGRBCalumet, Manitowoc39 min
Jul 13, 4:47 PM CDTSevere Thunderstorm WarningMKXFond du Lac43 min
Jul 13, 4:51 PM CDTSevere Thunderstorm WarningDVNBuchanan, Delaware39 min
Jul 13, 4:58 PM CDTSevere Thunderstorm WarningARXAllamakee62 min
Jul 13, 5:00 PM CDTSevere Thunderstorm WarningMKXFond du Lac60 min
Jul 13, 5:29 PM CDTSevere Thunderstorm WarningARXClayton61 min
Jul 13, 5:31 PM CDTSevere Thunderstorm WarningDVNDelaware, Dubuque59 min
Jul 13, 5:44 PM CDTSevere Thunderstorm WarningMKXFond du Lac, Sheboygan38 min
Jul 13, 5:58 PM CDTSevere Thunderstorm WarningMKXSauk62 min
Jul 13, 6:15 PM CDTSevere Thunderstorm WarningDVNClinton, Dubuque, Jackson60 min
Jul 13, 6:25 PM CDTSevere Thunderstorm WarningARXGrant35 min
Jul 13, 6:39 PM CDTSevere Thunderstorm WarningMKXLafayette66 min
Jul 13, 7:04 PM CDTSevere Thunderstorm WarningMKXGreen41 min
Jul 13, 7:26 PM CDTSevere Thunderstorm WarningMKXColumbia, Dodge, Green Lake49 min
Jul 13, 7:29 PM CDTSevere Thunderstorm WarningMKXDane, Green, Rock61 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

Davenport, (KDVN), launched 12:00Z, 8.9 hours before the alert went out and 191 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, Davenport, at 12:00Z on 2018-07-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 55 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, Davenport, at 12:00Z on 2018-07-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 square meters per square second.1939Sfc1 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
55 J/kg
Mixed-layer CIN
-305 J/kg
Mixed-layer LCL
1344 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
104 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
Jul 12, 9:39 PM CDTMesoscale DiscussionSPCDickinson, Lyon, Osceola96 min
Jul 13, 12:41 PM CDTMesoscale DiscussionSPCBlack Hawk, Bremer, Butler, Calhoun, Cerro Gordo, Chickasaw and 16 more94 min
Jul 13, 6:23 PM CDTMesoscale DiscussionSPCClinton, Delaware, Dubuque, Jackson, Jones2 hr
Jul 12, 7:35 PM CDTMesoscale DiscussionSPCBlue Earth, Brown, Carver, Cottonwood, Dakota, Dodge and 18 more85 min
Jul 12, 8:14 PM CDTSevere Thunderstorm WatchSPCLanglade, Lincoln, Marathon, Menominee, Portage, Shawano and 3 more2 hr

Nearby

Severe Thunderstorm Watches in Wisconsin, 2018Severe Thunderstorm Watches in Iowa, 2018Severe Thunderstorm Watches in Minnesota, 2018Every severe thunderstorm watch in 2018

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.