EF0 Tornado — Monona, Iowa

2024-04-26 · near Preparation, Monona, Iowa

Event narrative

This is a continuation of the EF-1 tornado that touched down in Harrison County to the north-northwest of Magnolia, IA. The tornado was already weakening as it entered Monona County, only producing low-end EF-0 damage to trees as it crossed the county line. The tornado dissipated less than a quarter mile ENE of the intersection of Peach Avenue and 330th Street.

Wider weather episode

On the morning of April 26th, a potent negatively-tilted shortwave trough ejected out into the central Plains. Upper air analysis shows a jet streak on the downstream side of this trough with substantial divergence aloft over Nebraska. At the surface, morning cloud cover and drizzle across much of eastern Nebraska and western Iowa quickly gave way to partly cloud skies as a warm front moved north through the area, just after noon. At the same time, thunderstorms initiated along a pacific front/dryline in south-central Nebraska. One supercell produced several tornadoes from south-central Nebraska into Boone County, resulting in an EF-2 tornado just west of Cedar Rapids. A second round of supercells initiated in Jefferson and Saline counties. These long-track supercells produced the worst tornado outbreak the Omaha WFO has seen in 10 years. 5 EF-3 tornadoes were surveyed, with several of these tornadoes just shy of an EF-4 rating. One of these EF-3 tornadoes impacted the northeast side of Lincoln, Nebraska where 70 people were reported trapped in a manufacturing plant that collapsed as the tornado passed. Another long-track EF-3 tornado hit portions of Elkhorn, Bennington and Blair, Nebraska. Eppley Airfield was hit by the third EF-3 tornado of the day, doing damage to aircraft hangars on the southeast side of the airport before hitting homes in far western Pottawattamie County. The last two EF-3 tornadoes of the day both impacted portions of Pottawattamie County. While one remained primarily in rural areas in the central part of the county, the final EF-3 of the day hit the town of Minden, Iowa head-on, resulting in 1 fatality and 3 injuries. This was the only fatality of the entire event. This tornado continued into Shelby County, narrowly missing the towns of Tenant and Harlan. A total of 24 tornadoes were confirmed across both Nebraska and Iowa portions of the Omaha CWA. The strongest tornado was the EF-3 that impacted Elkhorn and Blair, with peak estimated wind speeds at 165 miles per hour.

View location on OpenStreetMap → (41.8640, -95.8850)

Source: NOAA Storm Events Database, event_id 1167510. Narrative written by the NWS forecast office that issued the report.