Iowa Severe Thunderstorm Warning | Effective 05/17/2026 20:39

Headline: 
Severe Thunderstorm Warning issued May 17 at 10:39PM CDT until May 17 at 11:00PM CDT by NWS Des Moines IA
Event: 
Severe Thunderstorm Warning
Urgency: 
Immediate
Effective: 
May 17, 2026 - 8:39pm
Expires: 
May 17, 2026 - 9:00pm
Description: 
At 1038 PM CDT, a severe thunderstorm was located over Marble Rock, or 11 miles west of Charles City, moving east at 55 mph. HAZARD...60 mph wind gusts. SOURCE...Trained weather spotters. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Mason City, Hampton, Allison, Clarksville, Nora Springs, Sheffield, Greene, Rockwell, Dumont, Bristow, Rock Falls, Hansell, Chapin, Aredale, Dougherty, Burchinal, Portland, Beeds Lake State Park, and Allison Municipal Airport.
Instruction: 
A Tornado Watch remains in effect until 100 AM CDT for north central and northeastern Iowa. For your protection move to an interior room on the lowest floor of a building. Intense thunderstorm lines can produce brief tornadoes and widespread significant wind damage. Although a tornado is not immediately likely, it is best to move to an interior room on the lowest floor of a building. This storm may cause serious injury and significant property damage.
Area Description: 
Butler, IA; Cerro Gordo, IA; Franklin, IA
Forcast Office: 
NWS Des Moines IA