EF1 Tornado — Union, Iowa

2024-04-26 · near Creston Arpt, Union, Iowa

Event narrative

This tornado began a few miles south of the Creston airport and moved northeast in rural portions of central Union County. This tornado damaged trees and grain bins shortly after forming with only tree damage observed for most of its path. The tornado crossed Highway 34 between Creston and Afton and passed along the Twelve Mile Lake Dam before dissipating.

Wider weather episode

Multiple rounds of storms moved across the area on April 26th. The first round was fueled by broad thermal lift and passed across Iowa through the morning with a few of these storms producing small hail but all remained sub severe. The area dried out and cleared out behind this round, allowing for a few hours of destabilization. By afternoon the warm sector was sufficiently unstable between the warm front and a dryline. Robust convection developed along that dryline in the afternoon in western Nebraska, moving into Iowa in the early evening. With sufficient instability, the increasing low level jet, and SRH exceeding 300 m2/s2, large hail and tornadoes occurred with storms across western to central Iowa. In all, 28 tornadoes occurred in Iowa with 18 within the NWS Des Moines area.

View location on OpenStreetMap → (40.9676, -94.3476)

Source: NOAA Storm Events Database, event_id 1170065. Narrative written by the NWS forecast office that issued the report.