Alert archive / Wisconsin / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 129, NWS Green Bay, WI

August 11, 2026Marathon County, Portage County, Wood County, Wisconsin

NWS Green Bay, WI issued this severe thunderstorm warning at Aug 11, 2026, 11:26 PM CDT for Marathon County, Portage County, Wood County, Wisconsin. It was in force for 64 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 11, 2026, 11:26 PM CDT (04:26 UTC)
Expired
Aug 12, 2026, 12:30 AM CDT
In force
64 min
Issued by
NWS Green Bay, WI
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Marathon County, WI, Portage County, WI, Wood County, WI

The radar

The Green Bay radar (KGRB), 132 km from the middle of the area, began a volume at 04:26 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 nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 4.4 hours before the alert went out and 338 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 00:00Z on 2026-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3969 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 00:00Z on 2026-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 121 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
3969 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
877 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
214 m²/s²
Significant tornado parameter
3.6
Supercell composite
29.8

Open this sounding in Storm Lab

The office that day

Everything else NWS Green Bay, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 10:15 PM CDTSpecial Weather StatementGRBMarathon, Menominee, Oconto, Shawano45 min
Aug 11, 10:43 PM CDTSevere Thunderstorm WarningGRBMarathon62 min
Aug 11, 11:01 PM CDTSpecial Weather StatementGRBMenominee, Oconto59 min
Aug 12, 12:19 AM CDTSpecial Weather StatementGRBWood26 min
Aug 12, 12:22 AM CDTSevere Thunderstorm WarningGRBWood38 min
Aug 12, 12:27 AM CDTSevere Thunderstorm WarningGRBMarathon46 min
Aug 12, 12:34 AM CDTSevere Thunderstorm WarningGRBPortage, Wood56 min
Aug 12, 1:05 AM CDTSevere Thunderstorm WarningGRBLanglade, Marathon, Menominee, Shawano40 min
Aug 12, 1:22 AM CDTSpecial Weather StatementGRBWaushara38 min
Aug 12, 1:39 AM CDTSpecial Weather StatementGRBMenominee66 min
Aug 12, 2:07 AM CDTSevere Thunderstorm WarningGRBMenominee, Oconto53 min
Aug 12, 2:48 AM CDTSevere Thunderstorm WarningGRBMarinette, Oconto42 min
Aug 12, 3:13 AM CDTSpecial Weather StatementGRBBrown47 min
Aug 12, 3:25 AM CDTSpecial Weather StatementGRBOconto35 min
Aug 12, 6:46 AM CDTMarine Dense Fog AdvisoryGRB3 hr

Nearby

Severe Thunderstorm Warnings in Wisconsin, 2026Every severe thunderstorm warning 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.