A fast-moving Arctic cold front forecast to dump up to a foot (30 cm) of snow on the East Coast of the United States on Tuesday shut down state and federal governments, closed schools and snarled air travel in its path.
Winter storm warnings and advisories are in place from the central Appalachian Mountains north to southern New England, the National Weather Service said, including all of the Middle Atlantic states and the busy I-95 highway corridor that connects cities like Washington, Philadelphia, New York and Boston.
Temperatures in the eastern half of the United States are expected to be from 10 to 25 degrees below average. Gusty winds will accompany up to a foot of snow in southern New England as the cold front picks up moisture from the Atlantic Ocean, it said.
"It will be a winter wonderland for these areas," the weather service said in a statement.
In Washington, hundreds of thousands of federal workers were ordered to stay home in the face of what was forecast to be the heaviest snowfall since five inches (12.7 cm) came down in 2011. City schools and offices also shut down, and the White House canceled its Tuesday press briefing.
But the Supreme Court remained open to hear cases, and organizers of the annual anti-abortion March for Life said Wednesday's rally would be held regardless of bad weather.
In neighboring Maryland the state government was shut down and the Maryland Transit Administration cut back rail and bus services. Further to the northeast, the inauguration party for New Jersey Republican Governor Chris Christie on Ellis Island in New York Harbor was canceled because of the looming storm.
Some schools in North Carolina closed early. Connecticut closed all its schools for Wednesday, and Hartford, the state capital, is sending students home early on Tuesday.
Nearly 2,300 flights in the United States had been cancelled on Tuesday in the face of the storm, according to FlightAware, a tracking service. The worst-affected airports were Philadelphia International and New York's LaGuardia.
Forecaster AccuWeather said the cold front would drop temperatures below freezing as far south as northern Florida.
Baltimore officials, expecting up to 10 inches (25 cm) of snow in central and southern Maryland, issued a Code Blue alert for potentially dangerous conditions, according to the Baltimore Sun newspaper.
Philadelphia was expecting up to 10 inches (30 cm) of snow, with wind chills in the Poconos mountains dipping down to -4 Fahrenheit (-20 Celsius), according to local CBS News station KYW-TV.
The National Weather Service said the cold air also would produce snow downwind from the Great Lakes.
While the polar front grips the eastern United States, the western half, the west will see above average temperatures as an ongoing drought worsens, the Weather Service said.
The polar air is something of a repeat of the cold snap that gripped much of the United States at the start of the year. Cold and snow snarled air and road travel, shattered temperature records and contributed to at least nine deaths.