Another day of frigid wind chills and brutal cold across much of the U.S.

BUFFALO, N.Y. — Brutally cold temperatures and dangerous wind chills stayed put across much of the U.S. Monday, promising the coldest temperatures ever for Iowa's presidential nominating contest, holding up travelers, and testing the mettle of NFL fans in Buffalo for a playoff game that was delayed a day by wind-whipped snow.

About 150 million Americans were under a wind chill warning or advisory for dangerous cold and wind, said Zack Taylor, a meteorologist with the National Weather Service in College Park, Maryland, as an Arctic air mass spilled south and eastward across the U.S.

Sunday morning saw temperatures as low as minus 20 degrees Fahrienheit (minus 6.7 degree Celsius) to minus 40 F in northern and northeast Montana. Saco, Montana, dropped to minus 51 F (minus 26 C). Subzero lows reached as far south as Kansas, Missouri, Illinois and parts of Indiana, Taylor said.

The Buffalo Bills renewed their call for shovelers at Highmark Stadium in Orchard Park, New York, on Monday morning to help dig out from more than a foot and a half of snow that fell through a blustery weekend that delivered the snow amid wind gusts of 60 mph (97 kph).

Crews had the turf cleared under a sunny sky by midmorning while citizen shovelers who took them up on the offer to earn $20 an hour worked in temperatures in the teens to clear seats for fans ahead of the 4:30 p.m. game.

At first glance it was a daunting task, Bob Isaacs of Buffalo acknowledged a few hours after arriving at 7:30 a.m. But he considered his work his contribution to the team.

“You got to remember you're a Bills fan. It’s all part of the deal," he said.

Neighboring towns saw even higher snow totals, thanks to roving Lake Erie-fed snow bands: 41 inches in Hamburg and Angola and three feet (about 1 meter) in West Seneca, Blasdell and South Buffalo.

Presidential campaigns, meanwhile, were expecting the cold and dangerous travel conditions to hamper turnout for the Iowa caucuses, which are the opening contest in the monthslong Republican presidential primary process. Voting is set to begin Monday night.

Monday also brought another day of delays for air travelers across the country. The flight tracking service FlightAware was reporting about 2,000 cancellations Monday within, into or out of the United States and thousands of delays.

In Utah, where almost four feet (1.2 meters) of snow fell in the mountains over a 24-hour period, a snowmobiler was struck and killed Sunday night by a semitrailer about 70 miles (113 kilometers) southeast of Salt Lake City, according to the Utah Highway Patrol. The person killed — the fifth death nationwide attributed to the Arctic cold — was among four snowmobilers attempting to cross U.S. Highway 40 in the Strawberry Reservoir area.

Swirling snow and avalanche dangers prompted road closures Monday across parts of Utah and Colorado. East of the resort community of Vail, Colorado, officials closed a 20-mile (32-kilometer) stretch of Interstate 70, the primary east-west highway through the state.

Authorities in northern Colorado opened a warming center for stranded motorists in Jackson County after all roads leading out of the county were closed.

Ice jam warnings were issued in Wyoming and Montana, where the bitter cold could cause rivers and streams to lock up with ice and overflow their banks.

Light snow was expected through the Mid-Atlantic and the Northeast through Monday and Tuesday, Taylor said, including 2 to 3 inches of snow forecasted for Washington, D.C. — what would be the most snowfall in a day in the nation’s capital in at least two years.

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