'Polar vortex' drives bitter cold into central, eastern U.S.
For the third winter in a row, the "polar vortex" is on the march again, dipping southward from the North Pole to drive a blast of bitter cold, ice and snow that could disrupt travel from Georgia to New England into early next week.
The National Weather Service says the unusually cold air mass will settle over much of the central and eastern U.S. this weekend, bringing the coldest weather of the winter season from the Great Lakes to New England.
Wind chill warnings — including possible "life-threatening" temperatures — were in effect Saturday for a large part of the Northeast and New England, with readings as low as 30 below zero expected in some parts of upstate New York. Actual temperatures will hit highs in the single digits and teens, and fall to subzero lows across much of Upstate New York and New England, the NWS says.
In Pennsylvania, first responders battled snow and 15-degree temperatures Saturday at the scene of a multi-vehicle pileup on I-78 about 90 miles northwest of Philadelphia. At least one person, and possibly as many as three, were killed, PennLive.com reported. At least one of four medical helicopters was forced to turn back because of the weather.
First responders said several people were huddling in the back of a tractor-trailer to keep warm as medical helicopters flew to the scene. Officers said by radio they were especially concerned about a woman, described as six months pregnant, who suffered a broken leg and lacerations to her face.
State police said a snow squall and poor visibility likely played a role in the crashes, that left some 50 cars, vans and tractor-trailers scattered along the roadway, Philly.com reported.
As the cold weather closed in, racing officials canceled all races Saturday at New York's Aqueduct Racetrack because of forecasts of extremely low temperatures and high winds. The New York Racing Association said made the move "out of an abundance of caution" for horses and jockeys, the Associated Press reported.
While it's not forecast to settle in for a long stay, the blast of cold weather could be sharp enough to trigger power outages and disrupt travel and flights near and along the East Coast. In interior southern and mid-Atlantic states, there were concerns that a buildup of snow and ice from a Monday storm system could also bring down trees and power lines.
"While the amount of snow and ice is not certain at this time, there is the potential for enough snow to shovel and plow in the Appalachians and interior Northeast," said AccuWeather senior meteorologist Alex Sosnowski. "Closer to the coast, a small amount of snow and ice could lead to very slow travel on the roads and numerous flight delays."
The polar vortex, which normally hugs the north pole in the stratosphere, is punching southward and driving the cold air ahead of it, apparently due to a sudden stratospheric warming.
"When this happens, lobes of the larger vortex can sweep southward toward southern Canada or northern Europe, helping to drive Arctic cold plunges into lower latitudes," said Jon Erdman of The Weather Channel. In effect, he says, the "solid wall" of the vortex, which is normally confined to the polar regions, gives way.
