• Travelers can generally expect increased traffic over Thanksgiving, but there are factors this year that could add to the congestion.
• INRIX found that the best time to take off is after 9 p.m. on Wednesday and before 11 a.m. on Thursday.
• Below are some of the worst congestion times in America’s traffic lanes the day before Thanksgiving.

AAA predicts that nearly 4 million more people will take to the roads for Thanksgiving compared to last year, meaning travelers must be prepared for increased traffic.

Experts say the long holiday weekend, rising vaccination rates and opening of U.S. borders are all pushing more people to drive this year. A November AAA report predicts auto travel volumes will fall to less than 3% of pre-pandemic levels, with 48.3 million people traveling by car for Thanksgiving.

“There are some really big driving vacations.… Thanksgiving is one of them,” said Bob Pishue, analyst for transportation analysis firm INRIX. “(Traffic) won’t be as bad as it was in 2019. But the roads are definitely more congested than they were last year.”

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INRIX advice to travelers: go early

INRIX found that traffic delays nationwide are expected to be about 40% higher than normal for Thanksgiving.

But there are ways to combat traffic congestion. Pishue said morning departures tend to be ideal, especially now that there are fewer people heading to work or school during the pandemic.

INRIX has found that the best time to take off is after 9 p.m. on Wednesday, before 11 a.m. on Thursday and Friday, and before noon on Saturday and Sunday.

“Leaving in the morning is definitely the best bet,” he said. “Even on a normal day, the midday and afternoon traffic is quite heavy, and in many places it is just as bad now as it was before COVID.”

Why is traffic getting worse?

Travelers can generally expect increased traffic during major holidays like Thanksgiving, but there are factors this year that could add to the congestion.

A potentially disruptive storm could hit the central and southern United States early next week, potentially bringing heavy snow, rain and winds.

Car accidents are another concern this time of year. The National Highway Traffic Safety Administration warns that drivers have made “risky decisions” since the start of the pandemic, including driving under the influence or without seat belts.

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The agency estimates that 20,160 people died in motor vehicle crashes during the first half of the year, up 18% from 2020 and the highest number of fatalities expected in that period since 2006.

The NHTSA also saw a slight increase in the number of impaired drivers while on vacation. From 2015 to 2019, nearly 800 people died in crashes involving a drunk driver over Thanksgiving weekend.

“If we thought it was a problem before COVID, it’s definitely a problem now,” Pishue said. “We hope to see fewer deaths, traffic accidents and crashes, but with the way things went during COVID, that’s definitely a concern.”

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Which cities have the worst Thanksgiving traffic?

Not all traffic is created equal. Here are some of the worst congestion times in America’s traffic lanes Wednesday, the day before Thanksgiving.

► Atlanta: Interstate 85 South from Clairmont Road to Martin Luther King Jr. Drive should be 340% above normal between 1:30 p.m. and 3:30 p.m.

► Boston: Interstate 93 North from Quincy Market, MA Route 28 is expected to be 240% above normal between 1 p.m. and 3 p.m.

► Chicago: Interstate 290 West from Morgan Street to Wolfe Road is expected to be 329% above normal from 2:45 p.m. to 4:45 p.m.

► Detroit: Interstate 96 West from 6 Mile Road to Walled Lake is expected to be 211% above normal from 2 p.m. to 4 p.m.

► Houston: Interstate 10 West from Sjolander Road to Texas State Highway 330 is expected to be 344% above normal from 3:15 p.m. to 5:15 p.m.

► Los Angeles: Interstate 5 South from Colorado Street to Florence Avenue is expected to be 385% above normal between 3:45 p.m. and 5:45 p.m.

► new York: Interstate 495 East from Borden Avenue to Little Neck Parkway is expected to be 482% above normal from 2:30 p.m. to 4:30 p.m.

► San Francisco: Interstate 80 East from Interstate 580 to San Pablo Dam Road is expected to be 278% above normal from 4 p.m. to 6 p.m.

► Seattle: Interstate 5 South from Washington State Route 18 to Washington State Route 7 is expected to be 257% above normal from 4 p.m. to 6 p.m.

► Washington DC: Interstate 95 South from Interstate 395 to Virginia State Route 123 is expected to be 230% above normal from 2 p.m. to 4 p.m.

Follow USA TODAY reporter Bailey Schulz on Twitter: @bailey_schulz.