LAKE DELTON, Wis. (AP) -- Flash floods inundated a southwest Wisconsin town Monday for the second time in 10 months, while 60 miles away an embankment along a man-made lake gave way, unleashing a powerful current that ripped homes off their foundations.

The swollen Kickapoo River engulfed nearly the entire village of Gays Mills, forcing about 150 people to evacuate. The town was reduced to a grid of canals with cars submerged up to their windows and parking lots looking like lakes, just as it was last August.

Floodwater threatened dams across the Midwest, and military crews joined desperate sandbagging operations to hold back Indiana streams surging toward record levels. Stormy weekend weather was blamed for 10 deaths, most in the Midwest.

While the Midwest struggled with flooding, the East was locked in a sauna. Heat advisories were posted Monday from the Carolinas to Connecticut, with temperatures topping 100 from Georgia to Virginia. New York City recorded a high of 99.

The U.S. Army Corps of Engineers said Monday it would close a 250-mile stretch of the Mississippi River -- from Fulton, Ill., to Clarksville, Mo. -- as soon as Thursday because of flooding, bringing barge traffic to a halt.

The closure could last up to two weeks, corps spokesman Ron Fournier said.

In Wisconsin, an embankment forming the side of the man-made Lake Delton failed, and the water poured out into the nearby Wisconsin River. The 245-acre lake nearly emptied, washing out part of a highway, sweeping away three homes and tearing apart two others.

''It's horrible. There's no way we could stop it,'' said Thomas Diehl, a Lake Delton village trustee. ''The breach is between 300 and 400 feet wide. The volume (of water) was just so great there wasn't anything anyone could do.''

In Gays Mills, residents stood on the edge of their ruined town, so close to finally turning the corner before this latest flood.

''I can't believe this is happening again,'' said Liz Klekamp, 23, who said she grabbed her cat and fled Monday morning when water came pouring into her house. ''It's really, truly sad.''

When asked if this was the end of the town, Village President Larry McCarn just stared ahead. ''It could be,'' he answered.

A couple thousand people in Columbia County about 30 miles north of Madison were urged to evacuate below the Wyocena and Pardeeville dams, said Pat Beghin, a spokesman for the county's emergency management.

The Wyocena Dam's spillway had washed out, and workers were sandbagging to try to save it, Beghin said. The Pardeeville dam also was overflowing, he said.

A new storm system headed toward the Ohio Valley from the southern Plains on Monday, dumping 4 inches of rain on parts of Oklahoma, where authorities said wet roads contributed to the deaths of two motorists in separate accidents. Two inches of rain fell Monday on already waterlogged Indiana.

In western Ohio, at least one tornado was reported Monday and a train was blown off its tracks. No injuries were reported.

The weather service posted a tornado warning for south-central Illinois and a severe thunderstorm warning for Indiana.

Some 200 Indiana National Guard members and 140 Marines and sailors joined local emergency agencies Monday in sandbagging a levee of the White River at Elnora, about 100 miles southwest of Indianapolis. The White River was forecast to crest Tuesday at nearby Newberry at 16 feet above flood stage.

By Monday morning, flooding at eight sites in central and southern Indiana had eclipsed levels set in the deluge of March 1913, which had been considered Indiana's greatest flood in modern times, said Scott Morlock, a hydrologist with the U.S. Geological Survey in Indiana.

President Bush late Sunday declared a major disaster in 29 Indiana counties. Iowa Gov. Chet Culver said nearly a third of his state's 99 counties need federal help. Wisconsin Gov. Jim Doyle had declared 30 counties in a state of emergency.

The Danville River Dam in Danville breached its banks Monday, and more than 100 people were taken by airboat from an apartment complex, condo building and several homes, Mayor Nancy Osterhaus said.

In Ontario, Wis., the Kickapoo River left waist-high water on the village's baseball diamond Sunday and backed up sewers, forcing water up through manhole covers.

Bill Hagerman, 53, vacuumed mud out of his business, Precision Physical Therapy, where sewer water about a 1 1/2 feet deep had coated his weight machines and patient table with muck.

'I got hit hard,'' he said. ''Yesterday afternoon, it seemed to rain all afternoon, hard. It just seemed like forever.''

Along the East Coast, people sweltered through the heat wave.

In the fifth inning of the Kansas City Royals-Yankees game in New York, fans cheered loudly when a cloud moved in front of the sun, then booed moments later when the sun returned.

''We came to New York and the whole week is hotter than in Florida,'' Patti Yost, 47, of Spring Hill, Fla., said at Yankee Stadium.

The heat also wore down tourists in Washington. ''We're going to get back on the Metro and go to the hotel and get into the pool,'' Jeanne Ringel of Redondo Beach, Calif., said outside the Smithsonian's Freer Gallery of Art.

New York City opened 300 cooling centers Monday, said Office of Emergency Management spokesman Chris Gilbride. District of Columbia officials declared Monday and Tuesday Code Red days for poor air quality, and schools in parts of New York, Connecticut, New Jersey, Pennsylvania and Maryland closed early as classrooms heated up. Employees at the Ohio Department of Health got the day off because of trouble with the air conditioning in their building.

The weekend death toll included six in Michigan, two in Indiana and one each in Iowa and Connecticut.

Copyright 2008 The Associated Press