EF1 tornado in Cass County, Nebraska

An EF-1 tornado formed on the southwest side of Plattsmouth east of Highway 75. The tornado moved northeast and snapped several pine trees on the top of a small incline that had a house and several grain bins. One empty grain bin was destroyed. The tornado continued northeast, causing minor tree damage and light damage to some mobile homes. Maximum wind speeds were estimated at 104 mph.

Severe thunderstorms produced hail, damaging wind gusts, and tornadoes across eastern Nebraska on May 17, 2026. On this day, an upper-level trough axis remained well to the west, but an embedded shortwave and attendant jet streak ejected from eastern Colorado into eastern Nebraska. At the surface, an elongated trough extended from a low in southeast Colorado through south-central Nebraska into southeast South Dakota, acting as a persistent focus for strong deep moist convergence. During the afternoon, a narrow dryline surged into central Nebraska and Kansas. East of the boundary, warm-sector dewpoints recovered into the mid-to-upper 60s, yielding a highly unstable environment with 3,000 to 4,000 J/kg of MLCAPE. Although mid-level winds were somewhat weak'resulting in unimpressive 0'6 km bulk shear'low-level hodographs featured ample cyclonic curvature. This provided sufficient low-level shear to keep updrafts organized and separated from downdrafts despite the weaker flow aloft.

A broken line of strong to severe thunderstorms developed across east-central Nebraska during the afternoon, pushing eastwards and growing upscale into a formidable wind-producing convective system. The storms initially presented a mixed hazard of large hail and damaging winds as they impacted counties including Madison, Platte, Cuming, and Saline. Hail up to golf ball size (1.75 inches) was reported near Wisner, while quarter-size hail fell in several surrounding communities. Three EF-1 tornadoes were also confirmed across eastern Nebraska in Thurston, Saunders and Cass county. However, severe straight-line winds quickly became the dominant threat. Wind gusts consistently measured between 60 and 70 mph caused widespread tree damage, snapping large branches with noticeable tree damage reported in communities like Friend, Crete, and Fairbury.

As the line surged eastward through the mid-to-late evening, the severe wind threat pushed straight through the Lincoln and Omaha metropolitan areas before crossing the Missouri River into western Iowa. An automated station at the Lincoln Airport measured a 68 mph wind gust, while emergency managers and spotters reported 70 mph gusts across Lancaster and Sarpy counties. These intense winds resulted in minor structural damage, including a torn gutter on a home in Lincoln and a damaged street light in La Vista. The Omaha Eppley Airfield recorded a 63 mph gust as the storms swept through the metro. By late evening, the system accelerated across southeast Nebraska and southwest Iowa, producing severe wind gusts of 71 mph in Pawnee County, Nebraska, before finally weakening and exiting the region.