Alert archive / Iowa / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 304, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Aug 7, 2026, 12:46 PM CDT for Winnebago County, Worth County, Iowa. It was in force for 29 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 7, 2026, 12:46 PM CDT (17:46 UTC)
- Expired
- Aug 7, 2026, 1:15 PM CDT
- In force
- 29 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Winnebago County, IA, Worth County, IA
The radar
The Minneapolis radar (KMPX), 164 km from the middle of the area, began a volume at 17:45 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
Minneapolis, MN (KMPX), launched 12:00Z, 5.8 hours before the alert went out and 164 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.
- Mixed-layer CAPE
- 506 J/kg
- Mixed-layer CIN
- -343 J/kg
- Mixed-layer LCL
- 1332 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 211 m²/s²
- 0-3 km storm-relative helicity
- 250 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 7, 12:40 PM CDT, 6 minutes earlier.
Area forecast discussion, Aug 7, 12:40 PM CDT, 6 minutes before
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</html>Hazardous weather outlook, Aug 7, 4:22 AM CDT, 8 hours 24 minutes before
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</html>The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 7, 2:52 AM CDT | Dense Fog Advisory | DMX | Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 44 more | 6 hr |
| Aug 7, 1:07 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo, Hancock, Winnebago, Worth | 23 min |
| Aug 7, 1:12 PM CDT | Severe Thunderstorm Warning | DMX | Hancock, Wright | 48 min |
| Aug 7, 1:25 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo, Hancock, Winnebago, Worth | 50 min |
| Aug 7, 1:37 PM CDT | Severe Thunderstorm Warning | DMX | Cerro Gordo, Hancock | 53 min |
| Aug 7, 2:52 PM CDT | Severe Thunderstorm Warning | DMX | Bremer, Butler | 38 min |
| Aug 7, 3:49 PM CDT | Severe Thunderstorm Warning | DMX | Black Hawk, Bremer | 26 min |
| Aug 7, 3:53 PM CDT | Tornado Warning | DMX | Black Hawk, Bremer | 22 min |
| Aug 7, 4:16 PM CDT | Severe Thunderstorm Warning | DMX | Black Hawk, Grundy, Tama | 59 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.