A powerful arctic blast has swept into the US northeast, pushing temperatures to perilously low levels across the region, including New Hampshire's Mount Washington, where the wind chill dropped to -105F (-79 Celsius), forecasters said.
Wind-chill warnings were posted for most of New York state and all six New England states - Massachusetts, Connecticut, Rhode Island, New Hampshire, Vermont and Maine - a region home to some 16 million people.
The National Weather Service (NWS) said the deep freeze would be relatively short-lived, but the combination of numbing cold and biting winds gripping the northeast would pose life-threatening conditions well into today.
Schools in Boston and Worcester, Massachusetts, New England's two largest cities, were among those closed yesterday over concerns about the risk of hypothermia and frostbite for children walking to school or waiting for buses.
Boston Mayor Michelle Wu declared a state of emergency through tomorrow and opened warming centres to help the city's 650,000-plus residents cope with what the NWS has warned was shaping up to be a "once-in-a-generation" cold front.
The bitter cold forced a rare closing of a floating museum that presents a daily re-enactment of the 1773 Boston Tea Party, when a band of colonists disguised as Native Americans tossed crates of tea taxed by the king into Boston Harbor in protest. "It's too cold for that, we're closed," a receptionist at the museum said.
Early yesterday, the arctic surge flowing into the United States from eastern Canada was centred over the US Plains, weather service forecaster Bob Oravec said.
In Mount Washington State Park, atop the northeast's highest peak, temperatures fell to -45F (-46C) yesterday evening, with sustained winds of 90m/hr driving wind chill to -105F (-76 C), according to forecasters.
By comparison, air temperatures in Eureka, Canada's northernmost Arctic weather station, were hovering at -41 F (-41C) on Friday morning.
Boston was at 8F (-13 C) yesterday evening, while in Worcester, Massachusetts, 64km to the west, the mercury hit 3F (-16 C), with temperatures expected to fall even lower, according to forecasters.
Record cold was expected in both cities today. Forecasts called for a low of -6F in Boston, exceeding an 1886 record -2 for the date. Worcester was headed for a low of -11 today, which would break its previous 1934 record of -4 for the date.
