By Josh Levs. Holly Yan and Marlena Baldacci
A 69-point drop. That's what New York suffered as the city awoke to a wind chill temperature of 14 below zero on Tuesday -- down from a wind chill temperature of 55 on Monday.
And that's just a tiny pinpoint on a largely frozen solid nation.
From Boston to Washington to Atlanta, the polar vortex kept swinging Tuesday, a frozen ice chest hovering over more than 100 million people.
Temperatures in many areas were in the single digits, and well below zero with wind chills.
In the Deep South, hard freeze warnings were in effect from eastern Texas to the Florida Panhandle.
Farmers in Florida were keeping an eye on crops, concerned about a possible freeze.
Authorities have blamed at least 15 deaths on the cold so far, including 11 from traffic accidents and two involving hypothermia.
It's even too cold for polar bears and penguins. At Chicago's Lincoln Park Zoo, Anana -- a polar bear who never grew the thick layer of fat that bears in the Arctic do -- had to be brought inside Monday. And at the National Aviary in Pittsburgh, bald eagles and African penguins, "who are used to temperate climates," were taken off exhibit until the weather warms up, the facility reported.
Stranded Amtrak passengers
The nasty winter weather left 500 people stranded on three Amtrak trains overnight in northern Illinois, an Amtrak spokesman said.
The Bureau County Sheriff's Office said it responded Monday night after the trains were reportedly stuck in snowdrifts.
The Mendota Police Department received a report from Amtrak around 6 p.m. (7 p.m. ET) about a train stuck about 4 miles west of the city, Sgt. Ken Haun said. Officers tried to reach the train but couldn't because of the weather.
Amtrak worked to make other arrangements, putting some passengers on buses.
On one train, which was stuck near Kalamazoo, Michigan, about 300 passengers had to wait more than nine hours to reach their destination, CNN affiliate WXMI reported.
"It was kind of like purgatory," a passenger told CNN affiliate WLS, adding that it was "not quite hellish because there was good company." The train, which was bound for Chicago, finally arrived at the city's Union Station on Monday night, WLS reported.
Air travel affected, too
Two thousand flights were canceled within, into or out of the United States on Tuesday morning, according to flightaware.com.
New York resident Mindy Goldberg said her family's flight back from Mexico had been diverted to Boston because of the weather.
"I just called my kids' school to tell them they wouldn't be there, and she said, 'Everyone's stuck somewhere,' " Goldberg told CNN affiliate WBZ.
In Indianapolis, Los Angeles resident Jason Bentley decided to play in the snow outside the airport after learning that his flight home had been canceled Sunday. It was 15 below zero (26 below zero C).
"This is the wettest snow I've ever touched," Bentley said, "the easiest snow to make a snowman and to have snowball fights. It's also probably the worst (weather) I've ever been in because of the temperature."
Extreme wind chills mean flesh can freeze in as little as five minutes. Several major school districts are closed Tuesday, including those in Minneapolis and Atlanta, to prevent children from waiting outside at bus stops.
Chicago also opened up 12 centers for residents trying to stay warm, one of which was to stay open through Tuesday. Libraries and some other city facilities would also be open, said Evelyn Diaz of the city's Department of Family and Support Services. Quinn said 100 warming centers were open statewide.
When will this end?
Temperatures should start edging closer to normal starting Wednesday.
By Thursday, most of the country will be back to normal, CNN meteorologist Brandon Miller said. In fact, some temperatures may even be a bit higher.
CNN's and Kait Richmond, Deborah Doft, Matt Smith, Indra Petersons, Stephanie Elam, Paul Vercammen and Dave Hennen contributed to this report.
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