A dramatic sky opens up between snow squalls along the Interstate 5 freeway near Gorman, Calif., Wednesday, Nov. 27, 2019. Plows were running and CHP was escorting traffic in an attempt to keep the freeway open as long as possible. (David Crane/The Orange County Register via AP)

MINNEAPOLIS (AP) — A day after bringing havoc to the Rocky Mountains, a powerful winter storm rolled across the Midwest on Wednesday, threatening to scramble Thanksgiving plans for millions of people during one of the busiest travel weeks of the year.

The storm, which was blamed for one death and hundreds of canceled flights, pushed east into South Dakota, Iowa, Michigan, Minnesota and Wisconsin. It dropped close to a foot of snow in some areas even as the system weakened and headed toward New York and Pennsylvania.

But the West was not free of heavy weather. A “bomb cyclone” caused by a rapid drop in air pressure brought snow to the mountains and wind and rain along the California and Oregon coasts. Drivers on Interstate 5 near the Oregon-California border spent 17 hours or more in stopped traffic as blizzard conditions whirled outside. Some slept in their vehicles.

"It's one of those things, you couldn't make it up if you tried," National Weather Service meteorologist Brent Hewett said of back-to-back storms forming around the holiday.

Christina Williams and her 13-year-old son, who live in Portland, Oregon, got stuck in the storm as they tried to drive to the San Francisco area for Thanksgiving. Williams said she and other stranded drivers connected on Twitter using weather-related hashtags and began to communicate to find out what conditions were like in other parts of the backup.

“There were spinouts everywhere. There were trucks that were abandoned. And every time we stopped and started moving again, there were people who couldn't start moving again,” Williams said. “Every time we stopped I was like, ‘Is this it? Are we going to be here overnight?’”

It took more than 17 hours to reach Redding, California, where they got a hotel room, she said.

Snow and downed trees and power lines closed roads. Others were reduced to a single lane, transportation officials said.

Northbound lanes of Interstate 5, which runs parallel to the coast, were reopened later Wednesday from Redding, California all the way to the Oregon border. The southbound lanes at Ashland, Oregon, reopened earlier in the day.

Transportation officials and other agencies tried to communicate the seriousness of the storm, but many drivers were still caught by surprise, said Don Anderson, deputy director of the California Department of Transportation in Redding.

Minneapolis awoke to as much as 9 inches (23 centimeters) of snow. Drivers were warned to stay off the roads at least until the winds died down.

“If you can wait a little bit today, the better off you’ll be because the roads will be being cleared, and our snow is pretty much wrapping up,” said Tyler Hasenstein, a weather service meteorologist in Minneapolis.

At the city’s main airport, Delta Air Lines filled de-icing tanks, called in extra flight dispatchers and assigned some of its 20 in-house meteorologists to focus on the forecast.

Airport spokesman Patrick Hogan said three runways were open Wednesday, but Federal Aviation Administration data showed that travelers were still experiencing delays of more than an hour.

At Chicago’s O’Hare Airport, one of the nation’s busiest, the FAA said heavy traffic was causing delays of up to 30 minutes and rising. Airlines worried that things could get worse if winds picked up.

In the city’s Loop business district, high winds peeled a wooden sign off scaffolding at Willis Tower. The sign slammed into two vehicles and smashed a window, hurting a cab driver, who was taken to a hospital with an arm injury, police said.

The northern reaches of Wisconsin saw 7 to 10 inches (18 to 25 centimeters) of snow, with more coming down. The Milwaukee airport reported wind and rain, but there was no snow within a hundred miles of the city.

On Tuesday, weather-related damage and delays were widespread.

About 10 inches (25 centimeters) of snow mixed with winds that limited visibility and canceled about 30% of the 1,600 average daily flights at Denver’s main airport.

Southwest Airlines canceled about 200 flights. Spokesman Brad Hawkins said it would take a couple of days to rebook stranded passengers on other flights because there are few empty seats during the pre-Thanksgiving travel crush.

About 1,100 people spent the night at the airport, spokeswoman Alex Renteria said.

Airport workers handed out blankets, diapers, baby formula, toothbrushes and toothpaste to passengers who camped out on floors and in chairs.

One person was killed near the ski town of Vail when a tractor-trailer jackknifed and was hit by two other trucks on Interstate 70.

Before it’s over, the system’s effects could extend all the way to New England, where a chance of snow was possible over the weekend, the weather service said.

In New York, the windy forecast could mean disappointment for fans of the larger-than-life balloons flown at Macy’s Thanksgiving Day Parade.

Organizers prepared for the possibility of grounding the iconic balloon characters because of expected 40 to 50 mph (64 to 81 kph) gusts. Rules adopted after several people were injured by a balloon years ago require the balloons to be flown lower or not at all if sustained winds exceed 23 mph (37 kph) and gusts exceed 34 mph (54 kph). The decision will be made on parade day.

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Slevin reported from Denver. Koenig reported from Dallas. Associated Press writers Thomas Peipert in Denver; Bob Moen in Cheyenne, Wyoming; Olga R. Rodriguez in San Francisco; Gillian Flaccus in Portland, Oregon; Scott Sonner in Reno, Nevada, and Paul Davenport in Phoenix contributed to this report.

Traffic moves north along the Interstate 5 near the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019, near Gorman, Calif.. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
Snow falls along the Interstate 5 freeway at the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019, near Gorman, Calif.. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
A plow runs along the Interstate 5 freeway at the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019, near Gorman, Calif.. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
A dramatic sky opens up between snow squalls along the Interstate 5 freeway near Gorman, Calif., Wednesday, Nov. 27, 2019. Plows were running and CHP was escorting traffic in an attempt to keep the freeway open as long as possible. (David Crane/The Orange County Register via AP)
CHP guides traffic along the Interstate 5 freeway at the Tejon Pass, Calif., as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
Snow falls along the Interstate 5 freeway at the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
Tim Kalik shovels snow onto his daughter, Lucy, 9, in Stillwater, Minn. on Wednesday morning, Nov. 27, 2019. Lucy has a snow day from school today and is waiting for her friends to go sledding. Tim said he drove into St. Paul to his workplace but they let employees go home around 8:30 due to the weather. (Jean Pieri/Pioneer Press via AP)
A wind gust blows snow in the face of Savannah Hennessey, 9, as she cleans off her grandparents' car with her mittens after a snow day released her from school in St. Paul, Minn. Wednesday, Nov. 27, 2019. (Scott Takushi/Pioneer Press via AP)
A plow truck makes its way up the hill in front of the Cathedral of St. Paul, with the Capitol building in the backdrop on Wednesday, Nov. 27, 2019, in St. Paul, Minn. (Leila Navidi/Star Tribune via AP)
Large waves crash around the North Breakwater Lighthouse in Duluth, Minn., as snow falls on Wednesday, Nov. 27, 2019. (Alex Kormann/Star Tribune via AP)
Patrick Costanzo brushes snow off a friend's car on Wednesday, Nov. 27, 2019, in St. Paul, Minn. (Leila Navidi/Star Tribune via AP)
This Tuesday, Nov. 27, 2019 photo provided by the Mammoth Mountain Ski Area shows heavy snow fall at Mammoth Mountain Sj\koi Area in Mammoth Mountain, Calif. Blizzard conditions have closed Interstate 5 south of Ashland, Oregon, all the way to the California state line. The Siskiyou Summit at the border on I-5, typically one of the more perilous sections of freeway along the West Coast corridor in wintery weather, had seen 6 inches of new snow with 10 inches packed on the roadside. (Peter Morning/Mammoth Mountain Ski Area via AP)
This Tuesday, Nov. 27, 2019 photo provided by the Mammoth Mountain Ski Area shows heavy snow fall at Mammoth Mountain Ski Area in Mammoth Mountain, Calif. Blizzard conditions have closed Interstate 5 south of Ashland, Oregon, all the way to the California state line. The Siskiyou Summit at the border on I-5, typically one of the more perilous sections of freeway along the West Coast corridor in wintery weather, had seen 6 inches of new snow with 10 inches packed on the roadside. (Peter Morning/Mammoth Mountain Ski Area via AP)
This Tuesday, Nov. 27, 2019 photo provided by the Mammoth Mountain Ski Area shows a Caterpillar snow plow clearing a road at Mammoth Mountain Ski Area resort in Mammoth Mountain, Calif. Blizzard conditions have closed Interstate 5 south of Ashland, Oregon, all the way to the California state line. The Siskiyou Summit at the border on I-5, typically one of the more perilous sections of freeway along the West Coast corridor in wintery weather, had seen 6 inches of new snow with 10 inches packed on the roadside. (Peter Morning/Mammoth Mountain Ski Area via AP)
A California Highway Patrol unit follows a tow truck next to the median as other vehicles are lined up while stopped on northbound Interstate 5 waiting for the freeway to reopen just near Redding, Calif., Wednesday, Nov. 27, 2019. (Mike Chapman/The Record Searchlight via AP)
A seasonal business offers chain-up help as motorists put snow chains on their tires Wednesday Nov. 27, 2019 before driving over snowy Santiam Pass, Ore. (AP Photo/Andrew Selsky)
This Tuesday, Nov. 27, 2019 photo provided by the Mammoth Mountain Ski Area shows parked SUVs covered in snow at Mammoth Mountain in Mammoth Mountain, Calif. Blizzard conditions have closed Interstate 5 south of Ashland, Oregon, all the way to the California state line. The Siskiyou Summit at the border on I-5, typically one of the more perilous sections of freeway along the West Coast corridor in wintery weather, had seen 6 inches of new snow with 10 inches packed on the roadside. (Peter Morning/Mammoth Mountain Ski Area via AP)
This photo provided by Caltrans shows cars and trucks in stopped traffic on Interstate 5 near Dunsmuir, Calif., Wednesday, Nov. 27, 2019. Thanksgiving travel has been snarled in some places by two powerful storms. A winter storm blamed for one death and hundreds of canceled flights in the West moved into the Midwest on Wednesday and dropped close to a foot of snow in parts of Minnesota and Wisconsin. (Caltrans via AP)
In this photo provided by Caltrans, are cars and trucks in stopped traffic on Interstate 5 near Dunsmuir, Calif., Wednesday, Nov. 27, 2019. Thanksgiving travel has been snarled in some places by two powerful storms. A winter storm blamed for one death and hundreds of canceled flights in the West moved into the Midwest on Wednesday and dropped close to a foot of snow in parts of Minnesota and Wisconsin. (Caltrans via AP)
In this photo taken Tuesday, Nov. 26, 2019, provided by Caltrans, are cars and trucks in stopped traffic on Interstate 5 near Dunsmuir, Calif. A
Traffic moves north along the Interstate 5 near the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019, near Gorman, Calif.. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)
Snow falls along the Interstate 5 freeway at the Tejon Pass as travelers try to get in and out of Southern California for the Thanksgiving holiday, Wednesday, Nov. 27, 2019, near Gorman, Calif.. Plows were running and CHP was guiding traffic in an attempt to keep the freeway open as long as possible.(David Crane/The Orange County Register via AP)