AP Photo - Greg Spadavecchia jogs as snow starts to fall on Jan. 21 in Morris Plains, N.J.
A winter storm lashed the East Coast on Tuesday, bringing heavy snow, strong winds and frigid temperatures to 50 million people in major metropolitan centers as it raced from North Carolina to New England.
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As of late afternoon, snow was falling in Washington, Baltimore, Philadelphia, New York City, Hartford and Boston. Many parts of the Philadelphia area had already picked up as much as 6 inches of snow, according to the National Weather Service.
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As of 6 p.m. ET, airlines had canceled about 3,000 flights on Tuesday, according to flight-tracking service FlightAware. And, with the storm expected to persist into tomorrow, airlines have already grounded more than about 1,100 Wednesday flights -- including about 190 on JetBlue and more than 200 on American and its regional affiliates, according to FlightAware.
Snow is also wreaking travel havoc in parts of the Midwest: A nearly 60-mile stretch of Interstate 65 - both northbound and southbound - was closed in southern Indiana because of ice, snow and numerous crashes.
The Weather Channel also reported that heavy lake-effect snow near Gary, Ind., had stopped traffic on a section of I-80/94. Close to 20 inches of snow had been reported in Gary.
"Today's one of those days if you don't have to be out, you should just stay home," said Sgt. Jerry Goodin, spokesman for the Indiana State Police post in Sellersburg.
In Delaware, it took one driver an hour and 45 minutes to make a normal 20-minute drive from Wilmington to the New Castle area.
Winter storm warnings remained in effect along much of the Interstate 95 corridor up the coast, with expected accumulations of 6-12 inches, according to AccuWeather. Temperatures across the eastern U.S. will be 10 to 25 degrees below average.
Some of the worst conditions were forecast to hit the nation's capital, Baltimore and Philadelphia in the afternoon and evening hours, and the New York-Boston corridor from late afternoon through the overnight hours Tuesday night.
There will be little relief from the frigid air after the storm system passes. Just as commuters are digging out from the day-long snowstorm Wednesday morning, bitterly cold air will spread across the East. High temperatures will be at least 10 to 20 degrees below average, even as far south as Miami, according to AccuWeather.
Anticipating a commuting nightmare Tuesday, the federal government closed offices in the Washington area. Both chambers of Delaware's General Assembly also canceled sessions.
Michael Ferrell, executive director of the Coalition for the Homeless in Washington, said the district generally provides night shelter for about 2,000 homeless people on cold winter nights.
"We will keep existing shelters open 24 hours a day until the cold spell breaks," Ferrell said. He said some recreational facilities will be opened. Transit buses might even be strategically placed around the district as temporary warming sites.
Schools in Pennsylvania, New Jersey, Connecticut, Virginia, Maryland, West Virginia, Indiana, Ohio and Kentucky sent students home early or were closed for an extra day after the Martin Luther King Jr. Day holiday.
The snow Tuesday morning canceled classes for more than 150,000 students across northern Kentucky and southern Indiana.
For Jefferson County Public Schools in Louisville, it was the fifth time this school year parents had to scramble to find child care.
"This is getting beyond ridiculous," said Sarah Hansen, who was scraping an inch of ice off her windshield early Tuesday morning in order to take her two children to a friend's house. "I understand why they are canceling school, but as a working parent, I can't take five days off from work."
The prospect of heavy snow and dangerous driving conditions were cited for a decision to cancel a post-inaugural party Tuesday evening on Ellis Island for embattled New Jersey Gov. Chris Christie.
"The greatest totals are likely for southern New England, and gusty winds are likely in this area to accompany the snow," said weather service meteorologist David Hamrick. Blizzard conditions are likely in southeastern Massachusetts.