TRENTON, N.J. — Winter's latest delivery of misery slid across the East Coast after icing over parts of the Ohio Valley, snarling primary-day voting, delaying air travel and causing hundreds of traffic accidents.

Up to 4 inches of snow and sleet was forecast for northwestern New Jersey before it was expected to change over to rain Wednesday. A bridge over the Delaware River near Philadelphia closed during evening rush hour so crews could spread salt, and speed limits were lowered on others.

"Things got ugly really quickly," said New Jersey State Police Sgt. Stephen Jones. Vehicles slid off I-295 in southern New Jersey, and other highways were shut down, he said.

In Maryland, a bus slid on ice and hit a pickup truck, sending 17 people to hospitals, authorities said. Their conditions were not immediately known. There were seven accidents within a quarter-mile of that crash, police said.

The National Weather Service issued an ice storm warning through 7 a.m. Wednesday for the Washington and Baltimore regions. Forecasters said at least a quarter-inch of ice could build up on roads and sidewalks.

Maryland extended its polling hours by 90 minutes in Tuesday's primary because the weather created gridlock in areas, preventing people from voting.

In Pennsylvania, Gov. Ed Rendell extended Tuesday's deadline for political candidates to qualify for the state's April 22 primary until noon today, citing weather concerns.

At least one person was killed on New Jersey roads, where hundreds of accidents were reported. In Englewood, four police officers were taken to hospitals and five cruisers were damaged in accidents. Police in Clifton said they responded to 56 crashes.

"It's just unbelievable," Lt. Paul Haertel said.

The storm delayed air travel in the New York area, with flights into LaGuardia late by an average of two hours. Flights were also delayed or canceled at Philadelphia International Airport, where two of the four runways were shut down.

The system also dropped snow in the Midwest, where about 450 flights were canceled and all were delayed at Chicago's busy O'Hare International Airport.

In Michigan, highway officials got edgy as their supplies of road salt dwindled.

"We've got a couple hundred tons being delivered today, but it's getting pretty low," said Mark Sohlden, engineer-manager of the Gladwin County Road Commission. "The way the winter has been so far, we've pretty much exhausted a lot of our supply."

Winter storm warnings were posted from western Tennessee into New England as the storm left the Ohio Valley, where thousands lost power and at least four people were killed in traffic accidents.

Two people died in Kentucky after their car slid off an icy highway. At least two traffic deaths, along with dozens of injuries, were reported in Missouri.

In the mountains of central Colorado, rescue teams on Sno-Cats and snowmobiles delivered food, medicine and propane to people trapped in their homes by huge snow drifts.

About 100 people were believed stranded, and officials had answered 16 requests for supplies by Tuesday afternoon. Winds up to 70 mph have whipped several inches of snow into piles as high as 24 feet.

Wind also created problems Tuesday in the South.

Strong storms produced hail, damaging winds and possible tornadoes from Louisiana to Florida, spawning a tornado that killed a woman near New Orleans and winds that upset a moored ship on the Mississippi River.

The storms followed catastrophic weather in the South last week that produced the deadliest tornado outbreak in years. The Tennessee Emergency Management Agency on Tuesday reduced that state's death toll from the storms by one, to 31. That puts the overall toll from the storms at 56.


Contributing to this report were Associated Press writers Marcus Kabel in Springfield, Mo.; Jim Irwin in Detroit; Jim Suhr in St. Louis; Brian Witte in Baltimore; Peter Jackson in Harrisburg, Pa.; and P. Solomon Banda in Denver.