NEW YORK – Bitter cold and increasing wind speeds are battering the northeastern United States after temperatures fell dramatically overnight Saturday. The coldest wind chills in decades are being observed on Saturday, but according to The New York Times, “conditions across the region were expected to quickly become more moderate by Sunday.”

The newspaper is reporting that, “frigid conditions were expected to break records across the region. As of early Saturday, it had hit 4 degrees Fahrenheit in New York City, minus 6 in Hartford, Conn., and minus 15 in Concord, NH, with the wind making it feel much colder everywhere. The wind chill reading in Caribou, MN, hit as low as minus 48 overnight.”

More than 10,000 households in New York State were without electricity and government officials “urged people to stay inside and prepared for the possibility of widespread power outages” as authorities opened warming shelters according to The Times.

“This is one of the coldest events that we’ve seen in years… We’re encouraging people to stay indoors,” said Samantha Sheehan, a spokeswoman for the mayor of Burlington, VT.

“In Boston, where the deep freeze was minus 9 degrees Saturday morning, Gov. Maura Healey of Massachusetts said the doors at South Station, the downtown train hub, would remain unlocked for those who chose not to use the city’s other shelters… Mayor Michelle Wu of Boston declared a cold emergency through Sunday… In New York, a Code Blue was in effect, meaning that no one seeking shelter would be denied,” The Times reported.

“This is just kind of an Arctic intrusion,” said Stephen Baron, a meteorologist with the National Weather Service in Gray, Maine. “Sometimes in the winter the jetsream dips and the Arctic oscillation allows the cold air to come into our area for a day or two,” according to the Associated Press.

The Times noted that, “the atmospheric culprit behind the cold snap in the Northeast this weekend – the polar vortex – has descended on the United States after bringing bitterly cold Arctic air to Asia last month. The vortex, an expanse of cold, high-altitude air that generally circles the Arctic, occasionally shifts south from the North Pole. That causes temperatures to drop suddenly in the mid latitudes, as they did on Friday in Boston and New York City.”

The AP writes that, “the good news is that the cold air is expected to move out of much of the region by Sunday, when temperatures could rise to the 40s.”

“That’s quite a change,” the National Weather Service’s Baron said.

(Material from The New York Times and the Associated Press was used in this article)