Lightning blew siding and bricks off a home in Lincoln and a funnel cloud was spotted about 40 miles southwest of the city, near Exeter, but no damage was reported.
The storm struck about 7:15 p.m. a subdivision south of Elk City, Oklahoma, almost 110 miles west of Oklahoma City. The first one died when the tornado hit a moveable home park in Wisconsin and the other died when a twister smashed a housing division in Oklahoma.
Sheriff Fitzgerald said the lone fatality was in the Prairie Lake Estates trailer park.
Multiple people were trapped inside homes after the tornado, KOCO.com reported.
Chetek Mayor Jeff Martin estimated the park, about 40 miles north of Eau Claire, had around 50 homes. "At this time, we're just searching the area with the search terms and making sure there's no one injured, then we'll assess the damage", said Sheriff Fitzgerald.
A mobile home is among one of the most risky places to be during a tornado. More than 25 people were injured, the state said, without giving their conditions.
All residents of the mobile home park have been accounted for.
In 2013, a meteorologist from Oklahoma City faced extensive criticism after telling viewers to get in their cars and drive away from the storm, particularly those in mobile homes.
"Severe storms are expected to develop this afternoon from the Mid Missouri Valley into Wisconsin", says the Storm Prediction Center in a weather outlook.
Devin Feuerhelm told KMSP-TV that his sister, Lenna Samuelson, lives at Prairie Lakes Estates with her two daughters, Ashley and Brenna.
Reports indicated 2-inch diameter hail hit in Polk County and hail also hit the community of Somerset hard in St. Croix County, Griesinger said. Nolan escaped with just a couple of scratches, he said. While their home was flattened, the SUV next to it was untouched.
Meanwhile, Wis. Gov. Scott Walker declared a state of emergency for three counties in northwestern part of the state following a deadly tornado and damaging storms.
Sirens went off Monday in the Chetek area about 25 minutes before the powerful storm hit about 5:33 p.m.
The NWS says that almost 40 percent of all tornado deaths have historically occurred in mobile homes.
"There are several more people and businesses to thank for the support, food, water, et cetera, and in the coming days I hope to be able to thank them", Fitzgerald said.
One tornado touched down in Elk City in Beckham County, injuring at least 10 people and killing one. The area covers from the Texas Panhandle through Oklahoma to western Kansas, Nebraska and Iowa into Minnesota and Wisconsin.
"Large hail, tornadoes and wind damage also will be possible outside of these areas across parts of the southern and central Plains".