Some of the U.S.'s biggest cities braced for what's expected to be another mammoth snowfall in the Midwest and the Northeast — with as much as a foot and a half forecast through Friday.
Winter storm warnings stretched from Chicago through the New York tri-state region into New England — affecting an area home to almost 40 million people.
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The National Weather Service issued a blizzard warning for Nassau and Suffolk counties on Long Island in New York beginning at 6 p.m. ET Thursday, predicting inch-an-hour snow with 45-mph winds during the worst of it Thursday night.
"It's going to be a pretty significant storm, which will cause major travel disruption for a lot of people early in the new year," said Dave Houtz, senior meteorologist for The Weather Channel. "Any untreated roads will be a real mess."
An ice crew member shovels snow Wednesday during the 2014 Bridgestone NHL Winter Classic at Michigan Stadium in Ann Arbor, Jan 1, 2014.Noah Graham | National Hockey League| Getty Images
In New York City, which was warned to expect 5 to 8 inches of snow through Friday, the administration of newly minted Mayor Bill DeBlasio said it would do its best to keep outdoor subway, Long Island Rail Road and Metro-North trains moving, calling out the Metropolitan Transportation Authority's ice-busting equipment.
Bus riders might not be so lucky: If roads become impassable, bus service will be suspended, the MTA said.
In Boston, Mayor Tom Menino — in his last official act in office — pre-emptively declared a snow emergency for Thursday and closed the city's schools Friday as weather models pointed to up to 18 inches of new snow.
"What a New Year's gift, to receive one last snowstorm as mayor," Menino said Wednesday.
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Buffalo was also predicted to get a 12- to 18-inch wallop, and accumulations of 8 to 12 inches were expected in areas of Maine and Vermont farther north.
What changed the forecast so drastically from Tuesday, when meteorologists said the storm wouldn't be a big deal, was the expected convergence of three separate low pressure systems roaring in from the south and the east.
They're hauling warm, wet air on a course straight for the frigid Northeast, said Greg Postrel, a forecaster for The Weather Channel.