Alert archive / Wisconsin / Mesoscale Discussions in 2026

Mesoscale Discussion 396

April 13, 2026Allamakee County, Winneshiek County, Iowa; 6 counties in Minnesota; 31 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2026, 1:57 PM CDT for Allamakee County, Winneshiek County, Iowa; 6 counties in Minnesota; 31 counties in Wisconsin. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Apr 13, 2026, 1:57 PM CDT (18:57 UTC)
Expired
Apr 13, 2026, 3:30 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...tornado watch likely
Chance of a watch
80%
All 39 counties

Allamakee County, IA, Winneshiek County, IA, Fillmore County, MN, Goodhue County, MN, Houston County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Adams County, WI, Buffalo County, WI, Calumet County, WI, Clark County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Eau Claire County, WI, Fond du Lac County, WI, Green Lake County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Marathon County, WI, Marquette County, WI, Monroe County, WI, Outagamie County, WI, Pepin County, WI, Pierce County, WI, Portage County, WI, Richland County, WI, Sauk County, WI, Shawano County, WI, Trempealeau County, WI, Vernon County, WI, Washington County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The La Crosse radar (KARX), 51 km from the middle of the area, began a volume at 19:00 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.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 7.0 hours before the alert went out and 259 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 12:00Z on 2026-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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 12:00Z on 2026-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 124 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
8 J/kg
Mixed-layer CIN
-259 J/kg
Mixed-layer LCL
1506 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
124 m²/s²
0-3 km storm-relative helicity
229 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 13, 11:03 AM CDTMesoscale DiscussionSPCClinton, Des Moines, Scott87 min
Apr 13, 2:42 PM CDTMesoscale DiscussionSPCLyon, Sioux93 min
Apr 13, 2:59 PM CDTMesoscale DiscussionSPCDickinson, Emmet, Winnebago, Worth91 min
Apr 13, 3:11 PM CDTTornado WatchSPCAllamakee, Cerro Gordo, Emmet, Hancock, Howard, Kossuth and 5 more7 hr
Apr 13, 4:39 PM CDTSevere Thunderstorm WatchSPCClay, Dickinson, Lyon, O'Brien, Osceola, Plymouth and 1 more5 hr
Apr 13, 5:46 PM CDTMesoscale DiscussionSPCWabasha89 min
Apr 13, 6:02 PM CDTMesoscale DiscussionSPCBlue Earth, Brown, Le Sueur, Nicollet, Rice, Steele and 2 more88 min
Apr 13, 4:48 PM CDTMesoscale DiscussionSPCForest, Langlade, Marinette, Menominee, Oconto, Shawano117 min

Nearby

Mesoscale Discussions in Wisconsin, 2026Mesoscale Discussions in Minnesota, 2026Mesoscale Discussions in Iowa, 2026Every mesoscale discussion in 2026

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.