National Weather Service Confirms Two Tornadoes in Northern Iowa This Summer 🌪️

The National Weather Service (NWS) in Des Moines has confirmed two additional tornadoes from storms that occurred in northern Iowa on July 28 and August 17. Both tornadoes remained over agricultural land and caused no injuries or fatalities.

The first tornado was confirmed southwest of Crystal Lake in Hancock County late on July 28. Surveyors determined it tracked for about 1.24 miles with a maximum width of 20 yards. It began near the Lake George Wildlife Management Area around 11:50 p.m. and dissipated two minutes later just west of Iowa Avenue. The tornado has been given a rating of EF-U (unknown strength) due to the absence of measurable damage indicators.

The second tornado was confirmed west of Forest City in Winnebago County during the evening of August 17. High-resolution satellite imagery and photographic evidence showed a narrow landspout-type tornado with a path length of 0.45 miles and a width of 20 yards. It developed east of 100th Avenue around 6:13 p.m., crossed into nearby fields, and dissipated near a farmstead just south of 350th Avenue at 6:15 p.m. Like the Crystal Lake tornado, it was also rated EF-U because no structural or tree damage was available to estimate wind speed.

The Enhanced Fujita Scale, used to classify tornado strength, ranges from EF0 (65–85 mph winds) to EF5 (winds exceeding 200 mph). EF-U is reserved for tornadoes with confirmed tracks but without sufficient damage evidence to assign a wind speed estimate.

The NWS continues to review storm events across Iowa using ground surveys, photos, and satellite data to ensure tornado counts and ratings are as accurate as possible.