The nation's capital was at a standstill Tuesday evening as snow continued falling at a rate of about an inch an hour — while commuters across the Northeast struggled to get home through blizzard-like conditions.
The wintry wallop brought as much as a foot of snow and another blast of arctic air, snarling traffic, closing schools and shutting down the federal government.
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Initially forecast to be a modest blurt of cold weather, the system has intensified, unleashing wind-driven snow and frosty air on the Northeast Tuesday night into Wednesday.
In D.C., most offices of the government were shut down Tuesday — although the Supreme Court justices did show up for work — and officials were asking residents to stay off the roads.
"We've had about 80 calls for personal injury collisions today," said Scott Graham, assistant chief of nearby Montgomery County, Md., Fire and Rescue, told NBCWashington. "Some of which have been very minor... turning out to be property damage; some more significant, with minor traumatic injuries, vehicles overturning."
The capital was set to see about a half-foot of snow and wind gusts of 30 mph, while Boston could see around 8 inches and wind gusts up to 40 mph.
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Meanwhile, governors in Delaware, New Jersey and New York on Tuesday afternoon declared states of emergency as blizzard conditions hit along the heavily populated Interstate 95 corridor.
"This winter storm will bring a one-two punch of snow and extreme cold. I urge all those in the affected regions to exercise caution, and avoid travel if possible," New York Gov. Andrew Cuomo said.
New York broke three snowfall records Tuesday. And, for the first time since snow accumulation has been recorded in the 19th century, Philadelphia has had three 6-inch-or-greater snow events before Feb. 1.
"Every once in a while these little winter storms go bananas, and we think this might be the one," said Kevin Roth, a lead meteorologist with the Weather Channel.
Up and down the East Coast, area schools and city and state governments hunkered down, but with more than 3,000 flights cancelled, many airports were virtual ghost towns as well.
More than 6,300 flights were delayed and another 3,295 were canceled by 7:30 p.m., according to FlightAware.com. More than 900 flights for Wednesday have already been nixed.
A winter storm warning was in effect for New York City and the surrounding areas by the National Weather Service from noon Tuesday through Wednesday morning, and Mayor Bill de Blasio said the city has activated all of its emergency preparation systems, according to NBC New York.
The heaviest snow was expected in the later afternoon into the evening. Overnight lows could reach the single digits with the wind chill making it feel like 5 below.
The storm has already led some school districts in Pennsylvania, New Jersey, Connecticut, Virginia, West Virginia and Kentucky to send students home early Tuesday or cancel classes ahead of time.
It has also forced New Jersey Gov. Chris Christie to scrap a party Tuesday night on Ellis Island in celebration of his second inauguration.