Thunderstorm Wind — Decatur, Iowa

2025-09-17 · near Lamoni, Decatur, Iowa

Event narrative

Delayed report. Several large trees down in central sections of Lamoni, followed shortly by a 71 mph gust at the Lamoni airport.

Wider weather episode

Widespread scattered thunderstorms remained in place across northern and central Iowa through much of the day as a surface low approached the area. An axis of 1000-1500 J/kg of MLCAPE developed from southern into central Iowa where clearing allowed for quick heating. Weak shear of 15-20 kts limited more organized thunderstorms development. Storms largely remained sub-severe, however collapsing cores in southern Iowa did result in severe winds gusting over 60 mph and resulting in isolated areas of wind damage.

View location on OpenStreetMap → (40.6200, -93.9300)

Source: NOAA Storm Events Database, event_id 1297893. Narrative written by the NWS forecast office that issued the report.