Waterloo, IA Tornado History — 130 Tornadoes Since 1950
How many tornadoes has Waterloo, IA had?
Waterloo has had 130 tornadoes on record within 25 miles since 1950, including 11 violent (EF3+) tornadoes.
When was the most recent tornado near Waterloo?
The most recent tornado within 25 miles of Waterloo was an Unrated on August 18, 2025.
When is tornado season in Waterloo?
June is historically the peak month for tornadoes near Waterloo, with 36 on record. Spring through early summer (April–June) generally sees the highest activity across most of the central and southern United States.
At a Glance
Recent Tornado Activity Near Waterloo
The last 20 years of confirmed tornadoes within 25 miles — 35 total, averaging 1.8 per year over this window.
Preliminary tornado reports near Waterloo since December 29, 2025
These are 2 preliminary reports, not confirmed tornadoes. They have not yet been through an NWS damage survey, and are not counted in the confirmed totals above.
Preliminary reports are revised, merged, and sometimes withdrawn — historically about 23% are consolidated downward once surveys complete. Ratings are omitted until a survey assigns one.
Confirmed records above are complete through December 29, 2025. NOAA publishes the confirmed archive annually, so tornadoes after that date appear here first and move into the totals above once finalized.
Within 25 miles of Waterloo. Source: NOAA Storm Prediction Center preliminary storm reports, updated daily.
Tornadoes by Decade
Tornadoes by Enhanced Fujita Rating
F0–F5 ratings (pre-2007) are grouped with their EF equivalents. The Enhanced Fujita scale replaced the original Fujita scale in February 2007.
Tornadoes by Month
Casualties on Record Near Waterloo
17 fatalities have been recorded within 25 miles of Waterloo since 1950, across 5 events. 311 injuries have been reported across all events. 2008 was the deadliest year on record.
The deadliest single event was an EF5 on May 25, 2008, which caused 9 fatalities along a 41.0-mile track.
Notable Tornadoes Near Waterloo
About Tornadoes in Waterloo
This overview was written July 24, 2026. The tornado counts and notable-event figures elsewhere on this page reflect the latest data and may differ from this summary.
Waterloo lies in northeastern Iowa along the Cedar River, in the rolling farmland that defines much of the state's interior. It sits within the tornado-prone heart of the country, where the open terrain of the Upper Midwest gives passing storm systems little to slow them down through the warm season.
The tornadoes here are born of clashing air masses. Warm, moist air moving north from the Gulf of Mexico meets cooler, drier air descending from Canada, and when a strong jet stream aloft supplies wind shear, thunderstorms can organize into the rotating supercells that spawn tornadoes. The season builds from late spring into summer, when heat and humidity make the atmosphere most unstable, though the threat is never entirely absent in the warmer half of the year.
Tornado intensity is rated on the Enhanced Fujita (EF) scale, which runs from EF0 to EF5 based on a survey of the damage rather than a direct wind measurement. Most tornadoes are weak, but the region's climate is capable of producing strong and occasionally violent ones. For the specific tornado history near Waterloo — the total on record, the distribution by decade and rating, and the deadliest, costliest, and most recent events — refer to the figures compiled from the NOAA Storm Prediction Center elsewhere on this page.