The arctic air blast that cut through the region Saturday set records for dangerously low temperatures, knocked out power over wide swaths of the state, and played havoc with train and airline service.
Moving through the region like an uninvited guest, the frigid mass brought teeth-chattering, biting cold with windchills fierce enough to inflict frostbite in minutes, freeze pipes in unheated buildings, and bring daily life to a crawl.
“It is what we refer to as ‘bitter cold,’ " said Will Cosby, an official with the town of Hawley, where forecasters reported temperatures fell to minus 22 degrees Friday night. “Everyone is hunkered down.”
Hawley had the distinction, perhaps unfortunately, of having possibly the state’s coldest temperature, according to forecasters.
“We often get chills, cold weather in December or January. But I don’t recall anything quite this cold,” Cosby said.
Forecasters spent the day warning people to be very careful if they stepped outside, pointing to the threat posed by the extreme cold.
Boston set a new record for Feb. 4 when temperatures dropped to 10 degrees below zero at Logan International Airport early Saturday morning.
That smashed the previous record, set in 1886, of minus 2 degrees, according to Rob Megnia, a meteorologist for the National Weather Service in Norton.
Jon Latino, a spokesman for the Boston Public Health Commission, said more than 2,600 people have stayed at the city’s shelters since Thursday.
People also sought refuge in South Station, which Governor Maura Healey opened to serve as an emergency shelter late last month.
At South Station, people wrapped in blankets slept on the floor inside the station and on benches Friday night. MBTA Transit Police officers had a visible presence. Barbara V. Trevisan, a spokesperson for the Pine Street Inn, said the organization’s outreach teams counted 52 people who sheltered at the station Friday night.
At one point Friday night, about 45,000 customers across the state were without power. By Saturday evening, power had been restored for all but about 2,000 customers.
Along the MBTA’s subway lines, strong winds knocked down a 300-foot length of fence on the Red Line track, causing the MBTA to use shuttle buses for part of the morning Saturday, according to a spokesman. The Green Line was slowed after a track cracked due to the cold near Haymarket station.
The extreme cold also led to delays along the commuter rail, which reported downed power lines, signal issues, and track defects because of the weather, according to Sheri Warrington, a Keolis spokesperson.
At Logan, there were more than 270 delays and 86 cancellations reported in the late afternoon, according to flightaware.com. The flight issues were due to the cold in Boston and elsewhere, according to Massport spokesperson Samantha Decker.
Megnia said Saturday was the first time Boston dropped to double-digit temperatures below zero since Jan. 15, 1957. On that date, temperatures reached minus 12 degrees.
Worcester and Providence also broke records for Feb. 4, Megnia said.
Worcester fell to minus 13 degrees, breaking a daily record of minus 4 recorded in 1934, he said, while Providence’s temperatures reached minus 9 degrees, breaking a previous record for Feb. 4 of minus 2 reported in 1918.
But things were even colder in other places.
At Mount Washington’s observatory in New Hampshire, which records some of the most intense weather on Earth, the windchill reported on the mountain Friday night was minus 108 degrees, according to the observatory’s website.
Megnia said forecasters don’t track windchill records, but CNN reported that the New Hampshire figure would beat what meteorologists believe is the record low for windchill in the US — minus 105 degrees reported in Alaska.
But relief is coming Sunday, with temperatures expected to climb into the mid-40s in Greater Boston, according to the National Weather Service.
The rest of the coming week will be, if not comfortable, at least more tolerable. Daytime temperatures will be in the high 40s starting Sunday and remain there much of the week.
Expect mostly sunny skies through Wednesday, while Thursday and Friday look to be cloudy with chances of rain, according to the weather service.
Around Boston Saturday, the biting air drove most people indoors for the day. But a few brave — or crazy — souls could be spotted around Greater Boston, biking along the Charles with no hat or gloves, or taking out the trash wearing shorts.
In Cambridge, where streets were unusually busy due to the Hasty Pudding afternoon parade, Todd Bida hopped from one foot to the other trying to stay warm, while his daughter, Grace, stood bundled beside him on the sidewalk.
“I always loved winter, taking the kids out sledding when they were little, but this is pushing it,” he said.
The frigid temperatures, including those on Mount Washington, were “really testing my love of winter,” he said. “Was I planning to move to Florida? No, but I might be considering it after today.”
Across the water in East Boston, the streets were nearly deserted just before sunset, even as temperatures edged up above zero. Near the airport, a lone woman in a bright pink hat and matching mittens walked two large dogs by the water.
“I am definitely not a winter person, especially not today. But for these guys, I have to be,” she said.
In Hawley, a town of about 350 people, Cosby said he hadn’t heard of any trouble in the community due to the cold. People look out for one another, said Cosby, who has been checking in on his 97-year-old aunt, who lives up the street from him.
By Saturday afternoon, Cosby said he and his wife were just waiting out the cold. He rode his stationary bike; they had short ribs braising in the oven for dinner. Cosby ran outside a few times to check the pipes inside his family barn.
“We expect this to break,” Cosby said. “We’ll be back in the 30s, which is pleasantly warm by comparison.”
Shirley Leung of the Globe staff contributed to this report.