EF1 tornado in Blue Earth County, Minnesota

The tornado moved into Blue Earth County from Watonwan County. Based on multiple storm chaser videos, ground contact was evident most of the way, but not always, as there were two or three occasions when ground circulation was not evident for one or two minutes. But some storm chaser video showed it to be entirely from the same parent circulation, hence one tornado. The tornado hit several farms. At one farm, both garage doors on either side of a house were buckled in, multiple trees were snapped or large branches broken. Two farm outbuildings had their garage doors blown out. Some shingles were also removed. Dozens of trees nearby were blown over. A small trailer was blown over 100 yards. Another farm had two small outbuildings that were destroyed and trees down or broken. The maximum wind speed was estimated at 90 mph. This was based on drone video and ground-based photos provided by the Blue Earth County Sheriff's Office.

A southward moving cold front tracked across central and southern MN early Monday morning before stalling near Redwood Falls, MN over to Eau Claire, WI. Morning stratus associated with this frontal boundary aided an increased thermal gradient along this boundary. Later in the afternoon, a surface low centered over eastern Nebraska advected unstable air into much of southern MN. This airmass converged on the pre-existing stationary boundary which led to the initiation of several severe thunderstorms. Many thunderstorms produced large to very large hail measuring as large as 3.5 in diameter as well as four tornadoes across southern Minnesota.