Strongest Tornadoes Recorded in Iowa

The highest rating in the archive

The strongest rating represented in Iowa is F/EF5. When several records share that rating, this page highlights the one with the longest recorded path: 62.1 miles on May 15, 1968.

This is a database summary, not a definitive ranking of every historical tornado. Early events may have incomplete paths or retrospective ratings.

Rating is based on damage

Survey teams assign EF ratings by examining damage indicators and degrees of damage. The scale estimates a wind range from the damage that occurred; it does not measure every tornado’s maximum wind directly.

A violent tornado crossing open land may leave few indicators, while a lower-rated tornado can still be deadly when exposure and shelter are poor.

Impact across the full record

The state archive totals 2,237 injuries and 94 fatalities. Those human impacts cannot be compared by rating alone because warning access, time of day, construction, population, and storm speed matter.

Use historic events to improve present-day plans: reliable alerts, rapid shelter, head protection, and careful post-storm movement reduce avoidable risk.

Frequently asked questions

What month has the most tornadoes in Iowa?

June has the largest count in the SPC archive used here, with 775 recorded tornadoes. Individual years can differ sharply.

How many tornadoes have been recorded in Iowa?

The archive contains 3,011 records from 1950 through 2024. The total reflects reporting and database practices as well as weather.

What is the strongest tornado recorded in Iowa?

The highest rating in this archive is F/EF5. Fujita and Enhanced Fujita ratings are damage-based and are not directly interchangeable wind measurements.