Some 54.3 million Americans will travel 50 miles or more away from home this Thanksgiving, a 4.8 percent increase over last year, vastly increasing traffic on roadways in the skies, according to AAA projections.

The 2018 holiday weekend will see the highest Thanksgiving travel volume in more than a dozen years (since 2005), with 2.5 million more people taking to the nation’s roads, skies, rails and waterways compared with last year. For the 48.5 million Americans planning a Thanksgiving road trip, INRIX, a global mobility analytics company, predicts travel times in the most congested cities in the U.S. could be as much as four times longer than a normal trip due to the high volume of traffic.

“Consumers have a lot to be thankful for this holiday season: higher wages, more disposable income and rising levels of household wealth,” Bill Sutherland, AAA Travel senior vice president, said in a prepared statement. “This is translating into more travelers kicking off the holiday season with a Thanksgiving getaway, building on a positive year for the travel industry.”

The Thanksgiving holiday period is defined as Wednesday, Nov. 21 to Sunday, Nov. 25.

Here is a look at the 2018 Thanksgiving Holiday Travel Forecast by the numbers:

  • Automobiles: The vast majority of travelers – 48.5 million – will hit the road this Thanksgiving, nearly 5 percent more than last year, putting more traffic on the road.
  • Planes: The largest growth in holiday travel is by air, at 5.4 percent, with 4.27 million travelers.
  • Trains, Buses and Cruise Ships: Travel across these sectors will increase by 1.4 percent, with a total 1.48 million passengers adding to the traffic.
  • Drivers Beware: Thanksgiving’s Terrible Traffic

Based on historical and recent travel trends, INRIX, in collaboration with AAA, predicts drivers will experience the greatest amount of traffic congestion Thanksgiving week during the early evening commute period, with travel times starting to increase on Monday. Drivers in San Francisco, New York City and Boston will see the largest delays – nearly quadruple normal drive times.

“Thanksgiving is one of the busiest holidays for road trips, and this year will be no different,” says Trevor Reed, transportation analyst at INRIX. “Knowing when and where congestion will build can help drivers avoid the stress of sitting in traffic. Our advice to drivers is to avoid commuting times in major cities altogether or plan alternative routes.”

In most cases, the best days to travel will be on Thanksgiving Day, Friday or Saturday. Drivers should expect increased travel times on Sunday as most holiday travelers will be making their way home after the long weekend.