This article is more than 9 months old

This article is more than 9 months old

Two massive weather systems moving across the US – one over the upper midwest and a second “bomb cyclone” moving to the Rocky Mountains from the Oregon coast – are expected to upend travel ahead of Thanksgiving, one of the busiest holiday travel weeks of the year in the US.

Windy conditions brought by one of the storms could also ground the famous balloons at the Macy’s Thanksgiving Day parade in New York on Thursday.

Millions set for Thanksgiving disruption as storms sweep across US Read more

“It’s a real bummer,” Ally Lytle, a 20-year-old student at the University of Wyoming in Laramie, who will be unable to make 400-mile (645km) road trip home to Jackson Hole after the storm swept through the area on Tuesday, told Reuters.

Facebook Twitter Pinterest A traveler makes his way to a shuttle stop after a snowstorm at Denver international airport. Photograph: Bob Strong/Reuters

The northern Rocky Mountains and Sierra Nevada should expect to “get hammered with blizzard conditions”, and 1-3ft of snow in the coming days, causing “severe travel disruptions”, the National Weather Service reported.

In Oregon, the storm has already brought wind gusts of more than 106mph, with huge 34ft waves forming along the west coast. Some drivers were stranded for 17 hours or more in their cars on Interstate 5 near the Oregon-California border.

Heavy rains in southern California have doused this week’s Cave fire, but brought new threats of landslides and flooding. Residents in Santa Barbara who were spared fire were told to prepare to evacuate in case the deluge unleashes dangerous debris flows from the freshly burned mountains nearby.

In the upper midwest, winter storm warnings are in effect for much of Nebraska, South Dakota, Iowa, Minnesota, Wisconsin and the northern part of Michigan. The storm is expected to move east toward the Great Lakes.

NWS Twin Cities (@NWSTwinCities) Heavy snow coming down at NWS Twin Cities #mnwx #wiwx https://t.co/f6sFTvdX5I

Already, nearly 100 domestic US flights were canceled on Wednesday morning and more than 300 delayed, with the brunt of the misery around Minneapolis-St Paul, Minnesota, according to FlightAware. About 4.5 million Americans are expected to take a plane this holiday week.

In the midwest, wind gusts of up to 50mph were expected as far south as Arkansas and east to the Ohio Valley. This could cause wind gusts of up to 40mph in the New York City area, potentially grounding the giant balloons at the Macy’s parade.

At the same time, this Thanksgiving is expected to be the second busiest travel season since 2000, when the American Automobile Association (AAA) started tracking. More than 55 million people are expected to travel more than 50 miles by train, plane and automobile to get to their holiday destinations.

Facebook Twitter Pinterest Drivers make their way along snowy roads in Denver. Photograph: Joe Mahoney/Getty Images

“Strong economic fundamentals are motivating Americans to venture out this holiday in near-record numbers,” said Paula Twidale, the vice-president of AAA Travel. However, in conjunction with the weather, millions of travelers also means delays.

“With record levels of travelers, and persistent population growth in the country’s major metropolitan areas, drivers must prepare for major delays,” said Trevor Reed, transportation analyst at Inrix. “Although travel times will peak on Wednesday afternoon nationally, travelers should expect much heavier than normal congestion throughout the week.”

While millions will be affected, not all of the country is experiencing treacherous weather.

“Dry and mild conditions are expected to continue for Florida,” the National Weather Service said. The local weather service described the conditions as “mostly sunny and pleasant”.