Robert Stolarik for The New York TimesGregory Sanders and his partner, Keisha Washington, had just arrived at Pennsylvania Station in New York from Pennsylvania Station in Newark on Saturday night. The trip was beside the point. Mr. Sanders, 47, and Ms. Washington, 39, were homeless, and they needed a place to stay as a fierce winter cold gripped the region.
“The plan for the night is to try and stay warm,” Ms. Washington said. “And to sleep in here until they wake you up.”
Mr. Sanders, who was carrying his belongings in a black trash bag, added that they chose the station because “they don’t kick you out here.”
The temperature fell to 13 degrees in Central Park on Saturday night and was expected to plummet to 4 degrees on Sunday night, the lowest temperatures expected this winter. (The last time it was colder was on Jan. 18, 2000, according to the National Weather Service.)
While those numbers did not approach record lows, Seth Diamond, the commissioner of the Department of Homeless Services, described the string of frigid nights as “particularly dangerous.”
“You have to be particularly vigilant on nights like this,” he said on Saturday night, adding that his department had doubled the number of staff members on duty and vans on the streets over the weekend.
Teams of outreach workers checked on street dwellers every two hours under the department’s “Code Blue” procedure, which goes into effect when the temperature or wind chill drops below freezing and is heightened when the readings fall below 20 degrees, according to Mr. Diamond.
On those nights — Sunday was the 41st night that Code Blue had been invoked this winter — the department loosens its restrictions to attract those who would not normally sleep in shelters.
“You could walk into any shelter that is available, and you could get a bed,” Mr. Diamond said. “Our priority when it’s cold like this is just to get them into a place that’s warm.”
Still, some homeless people preferred to make their own arrangements. Ms. Washington and Mr. Sanders, for instance, said they had been shuttling between the two Penn Stations for about a week — since the building in Newark where they had been squatting was demolished.
James Williams, 50, said he normally slept outside in Herald Square, but on Saturday night he sought refuge in Penn Station. “I got to go somewhere to stay warm,” he said.
“The shelter is not the best place,” he added. “I don’t feel as comfortable, I can’t do what I want. Out here I can be free.”
Around 11:30 p.m., several of the homeless people staying the night in Penn Station burst into an impromptu dance session in front of a man banging on pots, pans and five-gallon plastic drums. As commuters watched, a woman who identified herself only as Sophie swayed with two men.
“Yes, I’m partying, I’m enjoying my life,” Sophie said as she sipped a beer.
Elsewhere, other New Yorkers seemed determined not to let the harsh winter night interfere with weekend fun — or work.
Matthew Everett, 38, a doorman at the ML Lounge, a nightclub on Broadway in Astoria, Queens, was well prepared with long johns, thermal socks and “combat-issued boots.”
“When it’s really supercold, I can’t feel my toes,” he said. “That’s how I know it’s brutal — even with the boots and the thermal socks.”
On Steinway Street in Long Island City, Queens, Dr. Ricardo Vanegas, 50, wore a hooded jacket and gloves while walking his Labrador, Chocolate.
“We walk at night during the summer 10 to 20 blocks,” said Dr. Vanegas, a professor of dentistry at New York University. “Now, he just wants to go back in.”
At Atlantic Terminal in Brooklyn, Robert Muñoz, 26, followed any mother’s advice: he layered. But in two thermal shirts, two pairs of thermal pants, two pairs of socks, a jacket, a coat and a scarf, Mr. Muñoz, a Los Angeles transplant, still struggled to keep warm.
He was about to resort to Plan B. “I’m going to get drunk,” he said, on his way to a birthday party in Manhattan. “That’s the best way to deal with the cold.”
Reporting was contributed by Nate Schweber, Tim Stelloh, Sarah Wheaton and Rebecca White.