MILWAUKEE, Wisconsin (AP) -- Hundreds of motorists were stranded in a massive traffic pileup on Thursday, and classes were canceled for thousands of students as the Midwest dug out from a major snowstorm.
School bus riders transfer to a private vehicle after three school buses got stuck in the snow in Somers, Wisconsin, on Wednesday.
Meanwhile, residents in the Great Lakes nervously eyed rising rivers.
In Wisconsin, traffic backed up for 19 miles south of Madison on Wednesday after semitrailer trucks got stuck on a hill. Gov. Jim Doyle later called a state of emergency, sending National Guard troops to help vehicles stuck in the jam blocking Interstate 90. Snowmobiles and all-terrain vehicles were used to check on the stranded motorists and bring them food or fuel.
As many as 800 vehicles remained stranded Thursday morning, according to Wisconsin National Guard Lt. Col. Tim Donovan.
"In some cases, the drivers seemed to have given up and gone to sleep," said Donovan, who assessed the backup from a helicopter.
More than 200 public school districts and private schools in southeastern, central and western Michigan canceled Thursday's classes, as did many community colleges. Dozens of schools in northern and eastern New York were closed or delayed the start of classes because of icy conditions.
General Mitchell International Airport at Milwaukee stopped all flights Wednesday afternoon because of whiteout conditions. More than 100 people spent the night in the concourses, airport spokesman Ryan McAdams. Air traffic resumed at 7 a.m. Thursday, although McAdams said delays were expected.
Lines at Chicago's O'Hare International Airport were long Thursday morning, a day after carriers canceled about 1,000 flights. Eighty flights were canceled Thursday morning, said Karen Pride, a spokeswoman for the Chicago Department of Aviation. About 100 passengers spent the night on cots.
No delays were reported across town at Chicago's Midway International Airport.
"Things are much improved from yesterday morning," Pride said.
Flood warnings were issued in Illinois, Indiana, Ohio and New York after three days of heavy rain and melting snow. People in northwest Ohio moved to higher ground as forecasters predicted that floodwaters would continue to rise in an area still recovering from flooding five months ago.
Rising waters from the Blanchard River in Findlay, Ohio, were another blow to residents and business owners just getting their lives back to normal after flooding in August displaced hundreds and caused millions of dollars in damage.
"We had the place completely gutted," music store owner Scott Adams said as he loaded equipment into a trailer to try to keep it dry. "I don't see fixing the place again."
The river was expected to crest before 9 a.m. at 5.5 feet above flood stage, the level at which the river began flowing over its banks, city Safety Director Jim Barker said Thursday morning.
The flooding wasn't expected to be as bad as August's -- the city's worst since 1913 -- but firefighters evacuated a handful of residents.
Water started spilling into downtown Wednesday afternoon, forcing the city's main thoroughfare to close where several storefronts remain empty from the last flood. Within a few hours, the entire street was covered by water, and at least 100 homes had suffered some water damage, Barker said.
In northwestern Indiana's Newton County, divers spotted at least one body in a vehicle submerged underwater in a quarry. The car may have plunged into the icy water overnight, Indiana Conservation officers said. A diver was unable to open the car doors, and the recovery effort was postponed until water could be pumped out, they said.
In upstate New York, freezing rain and snow contributed to a pileup that killed one person and sent another to a hospital, authorities said. In Wisconsin, two traffic fatalities were blamed on the storm.
Copyright 2008 The Associated Press. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed.