Heavy rain and strong winds continued to pound southern Minnesota and western Wisconsin early Friday with forecasters promising another round of rough weather later in the day.
The storms ripped roofs and walls off homes and knocked down trees in the Farmington area of Dakota County.
City administrator Peter Herlofsky says the damage ranged from siding and shingles pulled off to collapsed garages.
"People are trying to clean up before the next rain comes, and we're going to try to inform people to get building permits to get things fixed," Herlofsky said. "Most of the homes are livable, so I think what they're trying to do now is make sure they're fixed."
Neighbors told WCCO radio there were no warning sirens sounded before the damaging winds hit. There were no reports of injuries.
Officials aren't yet sure if it was a tornado that hit the north side of Farmington, but twisters were reported elsewhere in the state Thursday evening and early Friday morning.
The National Weather Service posted a severe thunderstorm watch for portions of southern and central Minnesota and northwestern and central Wisconsin.
Jeff Boyne, a forecaster with the National Weather Service, said Minnesota and Wisconsin could also see an uncomfortable heat index.
"We may see heat indices approaching 100 degrees across parts of southwestern Wisconsin and maybe 95 to 100 for the remaining central Wisconsin so those who might be out cleaning up make sure that you drink lots of water and try and stay cool if you can," Boyne said.
Boyne said the ground is already saturated after a week of rainfall.
"Anytime you get about an inch an hour in an urban setting you are going to have some issues there will be some flooding," he said.
A flash flood watch covers portions of Iowa and Southeast Minnesota -- including Dodge, Fillmore, Houston, Mower, Olmsted, Wabasha and Winona -- through tonight.
In Stearns County, Emergency Management Director Marv Klug says a tornado touched down in the western part of the county, damaging two pole barns, a garage, house and silo.
(MPR reporter Elizabeth Dunbar and the Associated Press contributed to this report.)
(Copyright 2010 by The Associated Press. All Rights Reserved.)