COLUMBUS, Ohio -- A broad snowstorm pushed eastward early Friday ahead of a powerful cold front, complicating the morning rush and closing schools a day after contributing to a crash in Ohio that killed four people in a van carrying disabled adults.
The edge of the storm, with light snow flurries, reached the Philadelphia area overnight, and up to 2 inches of snow was likely there and in the New York City area, according to the National Weather Service, which warned commuters to be careful trekking to work.
"People ought to take it easy when they get out on the road this morning," Weather Service meteorologist Bill Goodman said early Friday.
In Ohio, where icy cold winds and snow on Thursday contributed to occasionally treacherous road conditions, the Weather Service warned of a possible lake effect: arctic air blowing over the Great Lakes, picking up moisture and carrying it inland, creating narrow bands of heavy snow. A winter storm warning was in effect until Saturday morning.
The Cincinnati and Columbus school districts canceled Friday classes.
Light snow had begun falling across Ohio on Thursday morning, gradually intensifying throughout the day and continuing through the night. Up to 6 inches was expected Friday, more in the northern parts of the state.
A tractor-trailer spun out of control Thursday on a snow-slick Ohio road, killing four people.
The tractor-trailer jackknifed on Interstate 70, crossed the highway median and swerved into oncoming traffic, colliding with a small bus transporting adult disabled passengers, the Ohio Highway Patrol said.
Three passengers on the bus were killed, as was its driver. Six other passengers of the bus, which was carrying 11 people, were injured, as was the driver of the commercial truck, Sgt. Raymond Durant said.
Much of Pennsylvania woke up Friday to at least a coating of snow Friday morning, with a total of 5 to 7 inches expected across the western part of the state.
Many schools across the Pennsylvania delayed opening and a few closed in response to the winter weather. Nearly 20 school districts in New Jersey, where a light dusting of snow fell Friday, delayed opening.
Snowfall was heaviest in Minnesota and parts of South Dakota, where blowing winds piled up drifts too big for snowplow drivers to clear. In Illinois, six snowplows were involved in accidents, most when other vehicles rear-ended them. By Friday morning, parts of Wisconsin could see up to 12 inches of snow.
Snowflakes fell as far south as Alabama and Georgia.
Atlanta woke to an unusual glaze of ice on the roads Friday after light snow overnight melted and refroze. Authorities urged motorists to stay home in much of Georgia, at least until daylight so they could see ice patches.
A 50-year-old woman in the far northern suburb of Acworth died after skidding off a road late Thursday. About 27 vehicles were involved in a pre-dawn crash Friday at the junction of two interstates near the Hartsfield-Jackson Atlanta International Airport and three motorists were taken to hospitals.
Frostbite-inducing temperatures gripped much of the nation, and schools in at least 10 states were closed, as were roads and government offices.
Nowhere was it colder than in Bismarck, N.D., where wind chills hit a frighteningly frigid 52 below zero Thursday and the temperature reached 14 below. Windchills were still near 50 below in the Dakotas for a second day.
While North Dakotans get plenty of practice with bundling up, folks in other parts of the country were still learning the basics.
With temperatures on the Texas-Mexico border expected to near freezing Thursday night, officials in Laredo issued an advisory telling residents to "dress warmly and stay dry."
MacPherson reported from Bismarck, N.D. Associated Press writers John Seewer in Toledo, Ohio, and Lisa Cornwell in Cincinnati contributed to this report.