By Brendan O'Brien and Kim Palmer
MILWAUKEE/COLUMBUS, Ohio, Jan 5 (Reuters) - Residents of the Midwestern United States on Sunday braced for the region's coldest weather in two decades, with temperatures that forecasters warned would be life-threatening seen heading eastward during the week.
Icy conditions snarled travel across the Midwest and thousands of flights were canceled or delayed, some officials preemptively closed schools and a plane skidded off a runway into snow at a New York City airport, days after the Northeast was hammered by the first winter storm of the season.
"The coldest temperatures in almost two decades will spread into the northern and central U.S. today behind an arctic cold front," the National Weather Service said on Sunday. "Combined with gusty winds, these temperatures will result in life-threatening wind chill values as low as 60 degrees below zero (Fahrenheit/minus 51 degrees Celsius)."
In weather that cold, frostbite can set in on uncovered skin in a matter of minutes, experts warned.
The NWS said the widespread chill was a result of a relatively infrequent alignment of weather conditions, allowing the Arctic polar vortex to be displaced unusually far south.
"The weather pattern across North America right now is set up to be very favorable for the southward transport of Arctic air," said Bob Oravec, a National Weather Service meteorologist.
"It's not going to be long-lived," he added. "By the end of the week the temperatures definitely start to moderate across the whole of the country."
COLDEST GAME IN NFL HISTORY?
Fans of the National Football League's Green Bay Packers vowed to brave the Wisconsin weather to see a playoff matchup that could stand as one of the coldest ever games in league history.
Jacquie Tucker Braun, 44, was undaunted by a forecast for temperatures below zero F when the Packers match up with the San Francisco 49ers at 3:40 p.m. CST (2140 GMT).
"It's going to be a challenge to stay warm, but we're up to it," said Braun, who plans to bring her 14-year-old son Gryphon to the game. She is bundling up for the game, wearing four layers on top and three layers on the bottom, along with two pairs of socks and two pairs of gloves.
"We will see the game to the end unless there was some type of emergency," she said. "Being a Packers fan is in your blood, hereditary even."
Officials at the Packers' Lambeau Field promised fans two free hot cocoa or coffee drinks during the game, sports network ESPN reported.
Elsewhere in the Midwest, forecasters warned Chicago and Indianapolis could see overnight lows of minus 12 F, Minneapolis minus 29 F and Fargo, North Dakota, minus 31 F. The coldest temperature reported in the lower 48 states on Sunday was minus 40 F in the towns of Babbitt and Embarrass, Minnesota, according to the National Weather Service.
The northeast was forecast to see a brief thaw before intense cold returned late Monday.
About half of all flights arriving and departing Chicago O'Hare International Airport had been canceled on Sunday, according to FlightAware, which tracks flight statistics.
Nationwide, about 3,530 flights had been delayed by midday and 2,524 had been canceled.
In New York City, John F. Kennedy International Airport was closed for a couple of hours on Sunday morning after a Bombardier jet skidded off a taxiway soon after landing.
Minnesota Governor Mark Dayton has ordered all public schools in the state closed on Monday to protect children from dangerously cold weather.
Chicago officials said they planned to open schools on Monday despite the cold, but advised parents to use discretion in deciding whether to send their child to school.
But the city's teacher's union called for the schools to be closed, citing the dire forecasts.
"Common sense would dictate that (Chicago Public Schools) should close schools with at least 10 inches (25 cm) of snow already on the ground and a record-breaking low temperature of minus 10 degrees (Fahrenheit) forecast for Monday," said union president Karen Lewis.
Between six inches and one foot (15-30 cm) of snow was predicted from Chicago to Detroit, AccuWeather said, while icy sleet and rain was forecast for much of the Northeast.
GLOVES, FIREWOOD AND CHIPS
The cold snap, which comes during the slowest time of the year for shopping, could benefit retailers as they get ready to replace winter merchandise on shelves with spring items in a few weeks.
"It's mostly going to be dry, bitter cold so any retailer that has inventory left over from the holidays - jackets, scarves hats, gloves - they need to clear that," said Evan Gold, senior vice president at Planalytics, a weather consulting firm in Berwyn, Pennsylvania.
In Nashville, Tennessee, where temperatures were forecast to drop from about 56 F in the afternoon to 8 F overnight, Bradley Hite's firewood sales company FirewoodNashville.com was struggling to keep up with demand.
"It's been a lot more business (in the last couple of days). Just a lot more people coming in and picking it up. It's not normal," he said.
In Clintonville, Ohio, Janine Dunmyre found her local grocery store stripped of staples including milk, eggs and juice -- as well as some less-essential supplies.
"The chips aisle was decimated," she said. "Like everyone is planning to sit around for two days with snack food."
Dunmyre said she has already made plans for her four children to stay home from school on Monday due to cold temperatures and ice on the roads.
"I'm concerned more about everything turning to ice, not how much snow we are or aren't suppose to get," she said. "Wet power lines iced over means no power."