Fifty million people are in the path of a massive, "perhaps crippling" winter storm that could dump up to 2 feet of snow on parts of the East Coast over the weekend, according to the National Weather Service.
As of Thursday afternoon, 80 million people in 15 states were under winter weather watches, warnings or advisories, NBC News reported. In preparation, airlines were canceling fights, shoppers snapped up snow supplies and food and officials urged the public to stay safe when the snow hits.
The National Weather Service warns of heavy snow across the northern mid-Atlantic region, including Baltimore, Washington and Philadelphia. Snow will likely begin Friday evening and could continue for up to 36 hours.
The heaviest snow is forecast for areas west and southwest of Washington, D.C., which could receive 18 to 24 inches of snow. That would make it the second largest snowstorm in the capital's history.
"I'm told that it is only the second such time in recent history where this much snow in a single event has been forecasted," D.C. Mayor Muriel Bowser said at a news conference Thursday. The district's Metro system will be shut because of the storm; an area bishop told Catholics in his parish that they weren't obliged to come to Sunday Mass.
"I've lived in D.C. most of my life, and I don't know that I have ever lived through a forecast like this," Bowser said.
Philadelphia, meanwhile, could see more than a foot of snow, while New York City and Long Island could receive 8 to 10 inches. Wind gusts could reach 50 mph, reducing visibility to zero and causing power outages and coastal flooding.
National Weather Service Director Louis Uccellini called the storm a "relatively rare event" that could cost $1 billion and paralyze the east coast at a media briefing Thursday.
"We're seeing everything line up for a major storm system affecting the eastern third of the country," Uccellini said.
Uccellini, who wrote a two-volume textbook on northeast snowstorms said it was unusual for weather prediction models to be in such consensus.
"To have this level of consistency... We're living in interesting times. I haven't seen it," Uccellini said. "I would suggest that people pay attention to this system."
In the areas where blizzard conditions are possible, travel will be limited or impossible, the weather service warned. The strongest winds and potentially life-threatening conditions are expected Friday night through Saturday night.
Tennessee, Pennsylvania, Maryland, Virginia, North Carolina, and Washington, D.C. have declared states of emergency ahead of the storm, along with 21 counties in Georgia.
All major airlines have issued travel waivers allowing passengers to rebook flights to avoid the storm. Affected airports vary by airline but include cities in Kentucky, Tennessee and West Virginia all the way up the coast to New Hampshire and Massachusetts.
American Airlines is canceling the bulk of its flights in the Northeast. At its Charlotte hub, all 654 American flights are canceled for Friday. Flight cancellations will take effect at the three Washington and Baltimore area airports Friday afternoon, while flights through New York's three airports will be canceled Saturday afternoon.
The National Weather Service has issued a blizzard warning for Washington, D.C. and Baltimore, Maryland. Winter storm warnings are in effect for parts of North Carolina, Indiana, Kentucky, Georgia, Ohio, Pennsylvania, West Virginia, South Carolina, Tennessee, Virginia and Arkansas. Blizzard watches have been issued for New Jersey and New York, while Mississippi is under a winter storm watch.
Uccellini said the storm is developing as predicted over the South Central U.S. The system has already brought ice and freezing rain to Arkansas, Tennessee, Kentucky and North Carolina, which could also see heavy snow in the west, according to Gov. Pat McCrory. The icy mixture will affect some 7 million people and threaten the area's infrastructure.
Coastal flooding is a major concern in Delaware and New Jersey, with predicted wave heights of up to 15 or 20 feet, according to the National Weather Service. Uccellini said strong winds paired with lunar tides could pose lingering problems along the shoreline. When asked Thursday if New York City's subway system could be in danger of flooding, Uccellini would only say, "We’re not there yet in terms of our forecast."
The storm is expected to miss much of New England. Meteorologist Tom Hawley of the National Weather Service in Gray, Maine, said the storm's path could shift but right now "all indications are that it will not amount to much" in the region.