A record level of travelers during this year’s Thanksgiving holiday period is expected to create much heavier congestion on the country’s roads.

More than 55 million travelers plan to start the holiday season with a trip of 50 miles or more away from home, according to the American Automobile Association (AAA), marking the second-highest travel volume since it began tracking in 2000. The figure is an additional 1.6 million more people than last year, trailing only the record set in 2005.

The vast majority of holiday travelers will drive to their destinations and INRIX, the global transportation analytics company, expects the afternoon of Wednesday, November 27 to be the worst travel period nationally, with trips taking as much at four times longer than normal in major metros.

“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.”

The AAA says strong economic fundamentals has led to the expected rise in travelers this year.