A long weekend of ferocious winter weather loomed across the U.S. on Saturday, as a continuing wave of Arctic storms threatened to break low-temperature records in the nation's heartland, spread cold and snow from coast to coast and cast a chill over everything ranging from football playoffs to presidential campaigns.

As the three-day Martin Luther King Jr. Day holiday weekend began, the weather forecast for the U.S. was a crazy quilt of color-coded advisories, from an ice storm warning in Oregon to a blizzard warning in the northern Plains, high wind warnings in New Mexico and flood warnings in the mid-Atlantic.

Fallout from the storm included a 100-vehicle stall on Interstate 80 in Iowa, after semitrailers jackknifed on the slippery roadway and blocked traffic. Some cars were stuck in the same spot for five hours as blowing snow encircled the vehicles. Tow trucks had to be brought in to get them off the roadway.

“Many roads are drifted shut,” Sgt. Alex Dinkla of the Iowa State Patrol said. “They (road crews) are working the snow-blowers like crazy to get some roadways open, but they’re actually struggling. The minute they get them open, they’re actually blowing right back shut because of such high winds we’re seeing right now.”

Parts of Montana fell below minus 30 degrees Fahrenheit (minus 34 degrees Celsius) Saturday morning, and the National Weather Service said similar temperatures were expected as far as northern Kansas, with minus 50 F (minus 46 C) possible in the Dakotas.

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“Certainly, it's been very active across a large portion of the country. We've had, now, multiple back-to-back storms” parading across the country, weather service meteorologist Zach Taylor said. That typically happens at least a couple of times in the U.S. winter, he said, and “we're in the heart of it.”

Governors from New York to Louisiana warned residents to be prepared. Some states already had reported weather-related deaths earlier this week from avalanches in California and Idaho and cold exposure in Illinois' Chicago suburbs. In Wisconsin, a man died snow-blowing his driveway.

Power was out Saturday morning in hundreds of thousands of households and businesses, mainly in Michigan and Wisconsin, according to poweroutage.us. In Illinois, officials pleaded with Texas Gov. Greg Abbott to stop sending migrants to Chicago, where city-run shelters were full and some new arrivals were staying in parked “warming buses.” Abbott refused, while urging Texans to get ready for a chill with ice on the way Monday.

In St. Louis, the National Weather Service warned of rare and “life-threatening” cold.

In Iowa, an electronic billboard read 3 degrees F( minus 16 degrees C) Saturday morning in the capital of Des Moines.

Des Moines residents Katy Becker, 26, and her fiance, Dalton Gustafson, 30, were hoping to fly to Florida for a trip to celebrate their engagement and Becker’s birthday on Jan. 16. They got snowed in, but will try again Sunday.

“We’ll trade the dusty snow for some sandy beaches,” Becker said.

“Negative 20 to 80 degrees — 100 degree flip in temperature,” Gustafson added.

The air temperature in parts of the state could dip as low as minus 14 F (minus 26 C) on Monday, when Iowa's caucuses kick off the U.S. presidential primary season. And that was to say nothing of the wind: Forecasters said it would be Wednesday before below-zero windchills go away.

Republican contenders Ron DeSantis, Nikki Haley and former President Donald Trump all canceled weekend campaign events because of the winter storm.

Iowa plow operators struggled Saturday to keep roads clear amid heavy snow and winds gusting up to 30 mph (48 km per hour), which blew snow back onto roads as soon as they were cleared. The Iowa Department of Transportation warned against travel across the state.

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Dinkla said troopers had handled 86 crashes and 535 motorist assists since Friday. Most of the assists were to help stalled cars and trucks get unstuck. Fifteen people have been hurt in accidents. In one wreck on an icy interstate highway, a semitrailer hit a state patrol car and virtually destroyed it. The trooper escaped injury.

Even snow-free roads aren’t safe.

“The thing that we’re seeing is that people think that roadways are clear in a lot of areas, but they’re not able to slow down because the roadways are a sheet of ice,” Dinkla said.

In South Dakota, the air temperature Saturday morning was minus 17 F (minus 27 C) at the Crow Creek Sioux Reservation, but a whipping wind of 30 mph (48 kph) made it feel like minus 48 F (minus 44 C). With a homeless shelter already at capacity, tribal leaders opened a gym for others needing shelter.

Near-record cold in Kansas City will make for a frigid NFL playoff game Saturday night, when the Chiefs host Miami. Fans will be allowed to bring in blankets and first-aid stations were set up at Arrowhead Stadium. The Buffalo Bills’ playoff game against the Pittsburgh Steelers was moved from Sunday to Monday because of dangerous weather conditions.

Coastal areas in southern Maine and New Hampshire were pounded by between 1 and 2 inches (2.5 to 5 cm) of rain on Saturday morning, causing some roads to flood, said Justin Arnott, a National Weather Service meteorologist in Maine. He said Portland, Maine, was also bracing for flooding from a potentially record high tide in the early afternoon.

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