Alert archive / Iowa / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 169, NWS La Crosse, WI

August 11, 2026Fayette County, Iowa

NWS La Crosse, WI issued this severe thunderstorm warning at Aug 11, 2026, 6:56 AM CDT for Fayette County, Iowa. It was in force for 34 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, 6:56 AM CDT (11:56 UTC)
Expired
Aug 11, 2026, 7:30 AM CDT
In force
34 min
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Fayette County, IA

The radar

The La Crosse radar (KARX), 119 km from the middle of the area, began a volume at 11:59 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, 11.9 hours before the alert went out and 177 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 2026-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4334 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 2026-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 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
4334 J/kg
Mixed-layer CIN
-25 J/kg
Mixed-layer LCL
919 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
314 m²/s²
Significant tornado parameter
4.6
Supercell composite
37.0

Open this sounding in Storm Lab

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 1:41 AM CDTSpecial Weather StatementARXGrant19 min
Aug 11, 7:37 AM CDTSevere Thunderstorm Warning Considerable damage threatARXGrant54 min
Aug 11, 6:51 AM CDTSpecial Weather StatementARXChickasaw, Fayette, Floyd24 min
Aug 11, 7:07 AM CDTSevere Thunderstorm WarningARXAllamakee, Chickasaw, Clayton, Fayette, Howard, Winneshiek50 min
Aug 11, 7:24 AM CDTAreal Flood AdvisoryARXChickasaw, Floyd3 hr
Aug 11, 7:30 AM CDTSevere Thunderstorm WarningARXAllamakee, Winneshiek15 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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.