The Washington Post’s Robert “Dr. Gridlock” Thomson speaks with AAA MidAtlantic’s Lon Anderson about how Americans are travelling this holiday season and advice for a quick and safe trip. (The Washington Post)

More than 40 percent of the people in the Washington region may leave Santa a forwarding address because they plan to skedaddle from town over the holidays, an AAA survey reported.

The annual AAA travel survey ranks with fruitcake as a holiday staple, and it seems reasonable to assume that if 41.5 percent of people go someplace else, then a whole lot of people from someplace else are likely to come here to take their place for a few days.

Nobody knows that for sure — the survey doesn’t provide that information — but the one thing that people here can count on is that traffic will be a mess. It always is, and about 90 percent of the 2.3 million local folks who plan to say “arrivederci” for a few days plan to drive.

“During Christmas and New Year’s we will experience the highest travel volume this decade, especially by the roadways, the railways, and the waterways,” said AAA spokesman John B. Townsend II. “The one exception is the airways, and this year, even that is making a comeback.”

If that 2.3 million number seems high for a region with 5.8 million people, remember that it’s over a 10-day period and people only have to go a minimum of 50 miles to qualify as a holiday traveler. That said, however, AAA reports that those who are departing will travel an average of 765 miles round trip.

The total number of people who say they plan to travel is up 2.3 percent from last year, perhaps inspired by a 7.4 percent drop in gas prices last month, AAA said. The increase over last year’s travel already was seen during another peak travel time, Thanksgiving weekend.

Almost 6 percent of people with travel plans say they will fly somewhere, an increase over the number of people who flew last year.

“Area households are feeling more confident, highlighting a willingness to spend more ahead of the economic recovery, including longer trips which favor travel by air,” Townsend said.

Almost 100,000 local people say they will travel by rail or bus.

The mass movement from the Washington region is part of a national travel picture that will include 93.3 million people going somewhere more than 50 miles from home. That’s an increase of almost 2 percent over last year.

Air travel will see a larger increase, growing by 4.5 percent over 2010, as 5.6 million passengers take to the skies.

AAA defines the year-end holiday travel period from Dec. 22 to Jan. 1.