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Residents warily watched as rivers continued to rise Thursday from heavy storms that dumped as much as a foot of rain in the Midwest and left behind more than a dozen deaths.

Meanwhile, government forecasters said the floods washing over large parts of the Midwest are just a taste of things to come, with one meteorologist complaining about a jet stream "on steroids."

Record rainfall and melting snow packs will continue to cause rivers to overflow in large areas of the country, the National Weather Service said.

While the first day of spring brought much needed sunshine Thursday to Ohio and other states, authorities warned that many rivers would crest well above flood stage.

Flooding also was reported in parts of Arkansas, southern Illinois, southern Indiana, Missouri and Kentucky.

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The greatest flooding danger includes much of the Mississippi River basin, the Ohio River basin, the lower Missouri River basin, Pennsylvania, New Jersey, most of New York, all of New England and portions of the West, including Colorado and Idaho.

On Thursday morning, high water closed the eastbound lanes of Interstate 70 — a major east-west highway — for about 4 miles in central Ohio's Licking County, the State Highway Patrol said. The flooding was receding by midmorning, but there was no estimate of when the lanes would reopen.

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Morning commuters trying to reach downtown Columbus from the south were being detoured off heavily traveled U.S. 23, because its northbound lanes were flooded at Interstate 270.

Numerous traffic accidents were reported early Thursday in the Dayton area when water on roadways froze. The American Red Cross provided hotel vouchers for eight people who were flooded out of their apartments Wednesday in the Dayton suburb of Kettering. Cincinnati picked up 4.7 inches of rain and then traces of snow on Wednesday.

Days of rain turned the Midwest into a soggy mess, flooding roads, stranding motorists and displacing residents — with a cleanup bill likely to run in the millions.

"Overall moisture is unprecedented for this time of year over an area that extends over 1,000 miles," said Doug LeComte, a meteorologist at the government's Climate Prediction Center.

LeComte noted that a La Nina, an unusual cooling of the tropical Pacific Ocean has been under way and that often leads to wetter conditions in the U.S. Midwest — but this weather pattern has been out of the ordinary.

"What's happened in the last few months has not been a typical La Nina, the jet stream's been on steroids," he added.

The area recovered quickly from two days of heavy rain, said Mike Mantel, director of the Service Dept. in Miami Township, east of Cincinnati. One township road closed Wednesday because of high water was reopened Thursday, and streams were receding, he said.

"We're in really good shape, considering the rainfall we had," Mantel said.

President Bush declared a major disaster in Missouri on Wednesday night and ordered federal aid to supplement state and local recovery efforts in areas affected by flooding. Seventy counties and the city of St. Louis also are eligible for federal funding for emergency protective measures.

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Much of Ohio was under a flood warning Thursday, with some areas cautioned to watch for flash floods. Most of southwest Ohio had received more than 4 inches of rain, and officials in Butler County declared a state of emergency because of the rising waters.

Flooding along the Scioto River in Pickaway, Ross and Pike counties was expected to be the worst since January 2005. The river near Circleville was expected to remain over the 14-foot flood stage through Sunday, and Pickaway County authorities asked the Red Cross to prepare shelters for possible flood victims.

In Findlay in northwest Ohio, authorities closed off streets Wednesday after the Blanchard River had once again gone over the 11-foot flood level — the 10th time it has done so in the last 15 months. The National Weather Service predicted the river would crest Thursday afternoon at 12.3 feet.

"It is going to take some time to dry out with this type of rain put down on saturated ground," said Beverly Poole, a meteorologist with the National Weather Service office in Paducah, Ky. "It's going to take a few days for the rivers and the creeks to recover."

The Ohio River at Cincinnati was expected to rise about 2 feet above flood stage by Friday. In nearby Whitewater Township, rescue workers with boats helped 16 people to safety and urged 40 to 45 more families to leave their homes.

"American citizens should be on high alert to flood conditions in your communities. Arm yourselves with information about how to stay safe during a flood and do not attempt to drive on flooded roadways," said Vickie Nadolski, deputy director of the weather service.

Judy Booth, who's lived in a low-lying area of the township for 11 years, said Wednesday was the first time she's had to flee from flooding.

"You don't have no choice, you've got to go," said Booth, who was helped by fire-rescue squads who brought an inflatable boat to her water-surrounded home.

Retired truck driver George Slayton, 65, said he just wasn't sure how much water from the Black River flowed into his home in Piedmont, Mo. He only had time to grab some medication and a change of clothes.

"I believe in God and everything, but he does things sometimes that make you wonder," said Slayton, who found shelter at a church and slept on a padded pew.

Crews rescued a man clinging to a tree in the Ohio River after his truck was swept away at a boat ramp near Evansville, Ind. He showed signs of hypothermia and could not speak clearly.

"It's hard for anybody to say how long he could have survived there," Knight Township Fire Chief Chris Wathen said. "But I do think it was fair to say he was within minutes of losing his life."

At least 13 deaths have been linked to the weather over the past few days, and three people were missing.

Five deaths were blamed on the flooding in Missouri, five people were killed in a highway wreck in heavy rain in Kentucky and a 65-year-old Ohio woman appeared to have drowned while checking on a sump pump in her home. Most of the flood water had subsided in western Kentucky by Thursday.

In southern Illinois, two bodies were found hours after floodwaters swept a pickup truck off a rural road.

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Searches were under way in Texas for a teenager washed down a drainage pipe, and two people were missing Thursday in Arkansas after their vehicles were swept away by rushing water on Tuesday. Flood water remained standing in many places in Arkansas Thursday.

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The town of Fenton, Mo., put out a call asking volunteers to help put down sandbags against the floodwaters Thursday. Gov. Matt Blunt said state workers were checking on nursing homes and hospitals, mobilizing rescues, opening shelters, closing highways and working to ensure safe drinking water.

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