WINONA, Minn. — Relentless thunderstorms dropped up to a foot of rain on parts of Minnesota and Wisconsin, setting off mudslides and causing flooding that forced evacuations of entire towns.

Six deaths were reported in southeastern Minnesota and one man was missing today, authorities said.

Steady rain fell during the night as Minnesota National Guard soldiers guarded communities that were cleared out after the devastating flooding early yesterday. More rain was possible today, and flash flood warnings were issued for northern Iowa as well.

Sean Wehlage, 29, spent a harrowing night on the roof of his one-story home in Stockton before he was rescued.

“I cannot describe the terror of it all. I’m just glad to be alive,” he said.

His town of 803 residents was evacuated, as was Houston, a community of 995. Parts of Pickwick, Elba, and Winona, on the Mississippi River, were also evacuated. Governor Pawlenty ordered 240 National Guard soldiers to help and declared a state of emergency in six counties.

“This is the worst disaster that’s hit southeast Minnesota in a lifetime,” a state senator, Sharon Ropes, said.

In Wisconsin, Governor Doyle declared a state of emergency in three counties in the southwest corner of his state, where more evacuations took place and damage was estimated Monday in the millions of dollars.

Separately, the remnants of Tropical Storm Erin caused more flooding on the southern Plains, killing at least six people during the weekend in Oklahoma and one in Texas. Parts of Oklahoma got up to 9 inches of rain yesterday.

In Minnesota, the Army Corps of Engineers opened up the floodgates on the rising Root River to release some of the water creating pressure on the dike in Houston, a public information officer for Houston County, Tim Comstock, said. The dike was holding, he said.

Near Brownsville, eight people survived when mudslides pushed their houses over a bluff, the Winona Daily News reported. Four people died when their cars were swept off roads, two in a vehicle that plunged into a 30-foot gully near Witoka two others whose car was swept into a ditch in Stockton.

In Wisconsin, more than 200 homes were flooded in the Crawford County communities of Gays Mills and Soldier Grove, each with about 600 to 640 residents. Some houses had water 4 feet deep from the nearby Kickapoo River, a spokeswoman at emergency management’s Madison headquarters, Donna Gilson, said.

Amanda Crayne woke up Sunday in Gays Mills to find water up to the dining room windows. She dialed 911 and woke the six children, ages 6 months to 9 years.

“I grabbed diapers and baby wipes and formula and that was all I grabbed,” Ms. Crayne, 26, said as she hunkered down with the children at a Red Cross shelter last night.

More than 60 people were evacuated from a nursing home in nearby Soldiers Grove, and 23 others were evacuated from an apartment complex.

As the light rain continued to fall in southwestern Wisconsin this morning, there were stark reminders of the flooding. River bluffs and hillsides were pockmarked by mudslides and tree limbs littered roads.

June Jones, 52, has to cross a creek to get from her mobile home in Richland Center. Neighbor Joy Rux, 77, and her husband knocked on Jones’ door yesterday and told her police said they should leave. The three were at a Red Cross shelter Sunday night.

“It looked like the Mississippi,” Mrs. Rux said. “It came up so fast.”