Tens of millions of Americans endured bone-chilling temperatures, blizzard conditions, power outages and canceled holiday gatherings Friday from a winter storm that forecasters said was nearly unprecedented in its scope, exposing about 60% of the U.S. population to some sort of winter weather advisory or warning.

More than 200 million people were under an advisory or warning on Friday, the National Weather Service said. The weather service’s map “depicts one of the greatest extents of winter weather warnings and advisories ever,” forecasters said.

Power outages have left about 1.4 million homes and businesses in the dark, according to the website PowerOutage, which tracks utility reports. Utilities in Nashville, Memphis and throughout the Tennessee Valley said they were implementing rolling blackouts Friday to conserve power as the region battles an extreme cold front.

And more than 4,600 flights within, into or out of the U.S. were canceled Friday, according to the tracking site FlightAware, causing more mayhem as travelers try to make it home for the holidays.

“We’ve just got to stay positive. Anger is not going to help us at all,” said Wendell Davis, who plays basketball with a team in France and was waiting at O’Hare in Chicago on Friday after a series of flight cancellations. After his flight to Cincinnati, Ohio, was canceled Friday afternoon, Davis was considering renting a car and driving to Columbus, Ohio, beccause train service was suspended. But first, he was trying to locate his luggage.

A pair of travelers sleep while fellow travelers queue up below to pass through the south security checkpoint in Denver International Airport, Dec. 23, 2022, in Denver. More than 4,600 flights within, into or out of the U.S. were canceled the same day, according to the tracking site FlightAware.

A pair of travelers sleep while fellow travelers queue up below to pass through the south security checkpoint in Denver International Airport, Dec. 23, 2022, in Denver. More than 4,600 flights within, into or out of the U.S. were canceled the same day, according to the tracking site FlightAware.

Border-to-border ‘bomb cyclone’

The huge storm stretched from border to border. In Canada, WestJet canceled all flights Friday at Toronto Pearson International Airport, beginning at 9 a.m. And in Mexico, migrants endured unusually cold temperatures near the U.S. border as they awaited a U.S. Supreme Court decision on whether and when to lift pandemic-era restrictions that prevent many from seeking asylum.

Forecasters said a bomb cyclone — when atmospheric pressure drops very quickly in a strong storm — had developed near the Great Lakes, stirring up blizzard conditions, including heavy winds and snow.

Even though fleets of snowplows and salt trucks have been deployed, driving was hazardous and sometimes deadly. The Kansas Highway Patrol said three people were killed in separate vehicle collisions in northern Kansas this week. The collisions occurred Wednesday evening as bitter cold and snow was moving through the region. The drivers involved in the collisions lost control of their vehicles on icy roads.

In Kansas City, Missouri, a driver died Thursday after skidding into a creek. Meanwhile, state police in Michigan reported multiple crashes Friday, including a pileup involving nine semitrailers.

Activists also were rushing to get the homeless out of the cold. Nearly 170 adults and children were keeping warm early Friday in Detroit, Michigan, at a shelter and a warming center designed to hold 100 people.

“This is a lot of extra people” but you can’t turn anyone away, said Faith Fowler, the executive director of Cass Community Social Services, which runs both facilities.

In Chicago, Illinois, Andy Robledo planned to spend the day organizing efforts to check on unhoused people through his nonprofit, Feeding People Through Plants. Robledo and volunteers build tents modeled on ice-fishing tents, including a plywood subfloor.

“It’s not a house, it’s not an apartment, it’s not a hotel room,” Robledo said. “But it’s a huge step up from what they had before.”

In Portland, Oregon, officials opened five emergency shelters. Fallen trees and power lines have closed roads across the Portland metro area. And nearly 50 miles (80 kilometers) of Interstate 84, a major highway through the Columbia River Gorge, were closed Friday morning.

All bus service was suspended in the greater Seattle, Washington, area Friday morning. And DoorDash suspended delivery service because of hazardous conditions in parts of several states, including Minnesota and Iowa.

In far northern Indiana, lake-effect snow rolling off Lake Michigan could boost storm totals to well over a foot in some areas by Sunday, said Mark Steinwedel, a meteorologist with the National Weather Service in Syracuse, Indiana.

“It’s really going to add up,” he said, predicting “pretty awful travel.”

Coldest Christmas in decades

The weather service is forecasting the coldest Christmas in more than two decades in Philadelphia, where school officials shifted classes online Friday.

In South Dakota, Governor Kristi Noem late Thursday activated the state’s National Guard to haul firewood from the Black Hills Forest Service to the Rosebud Sioux Tribe as some members were stranded in their homes with dwindling fuel.

Other tribes also were struggling, including the Oglala Sioux Tribe in the western part of the state, which was using snowmobiles to reach members who live at the end of miles-long dirt roads.

But with the vehicles breaking down in the 10-foot drifts, officials were considering using horses to deliver essentials to some homes as they sought help from federal officials.

“It’s been one heck of a fight so far,” said tribal President Frank Star Comes Out.

In Maine, gusts approaching 70 mph (113 kph) were reported along the coast Friday morning. Atop New Hampshire’s Mount Washington, the tallest peak in the Northeast, the wind topped 150 mph (2410 kph). The governor closed state offices, ferry service to Casco Bay islands was suspended and flooding was leading to some water rescues.

In Boston, Massachusetts, rain combined with a high tide sent waves over the seawall at Long Wharf in Boston and flooded some downtown streets.

With temperatures dipping to 7 degrees (-13.9 Celsius) early Friday in northern Mississippi, Kyle Young abandoned the shorts that he normally wears to his job at a Starkville store that sells Mississippi State University clothing and decor.

“It’s freezing here,” said Young, who dressed in layers as he did a brisk business with last-minute Christmas shoppers. “I can usually tough it out.”

Mark Sorter's face is seen covered in snow and ice as he clears snow from a downtown ice skating rink, Dec. 23, 2022, in Des Moines, Iowa.

Mark Sorter’s face is seen covered in snow and ice as he clears snow from a downtown ice skating rink, Dec. 23, 2022, in Des Moines, Iowa.

In Jackson, Mississippi, the mayor had expressed concerns that the city’s beleaguered water system — which has led to numerous water shortages in recent years — remained vulnerable to subfreezing temperatures. But while there have been some water main breaks, the main water plants “held up to the temperature drops overnight,” city spokeswoman Melissa Faith Payne said.

It was so bad in Vermont that Amtrak canceled service for the day, and nonessential state offices were closing early.

“I’m hearing from crews who are seeing grown trees ripped out by the roots,” Mari McClure, president of Green Mountain Power, the state’s largest utility, said at a news conference.