EF2 Tornado — Union, Iowa

2024-04-26 · near Afton, Union, Iowa

Event narrative

This tornado developed west of Afton and quickly moved northeast. It crossed the BNSF railroad and Highway 34 before passing near the Three Mile Lake Dam. This tornado produced EF2 at one of the Wildlife Management Center's buildings before proceeding into rural areas of northern Union county. There was limited damage in this rolling terrain area with mostly tree damage although a few farmsteads were impacted with EF0 or EF1 damage. The tornado then crossed into Madison County northwest of Lorimor.

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 → (41.0195, -94.2701)

Source: NOAA Storm Events Database, event_id 1170052. Narrative written by the NWS forecast office that issued the report.