Powerful winds and at least one tornado slammed parts of Wisconsin, Iowa, Minnesota and Illinois, shattering windows and toppling power lines.
The only confirmed tornado was in Hastings, Minn., where a 100-yard-long swath of trees was flattened.
The National Weather Service received reports of a possible tornado near downtown Minneapolis, where winds tore off part of a 90-year-old metal church steeple.
In northeast Iowa, a barn roof was blown off near Stanley but only minor damage was reported, officials said. The weather service reported that tornadoes may have touched down in Illinois too.
A day earlier, a separate storm felled hundreds of century-old trees in New York's Central Park.