As more people try to get an early jump on the holiday, Tuesday before Thanksgiving is becoming the new Wednesday before Thanksgiving.

Tuesday isn't expected to be quite as busy as the nation's biggest travel day of the year, but if recent trends continue, it won't be far behind. At Maryland toll plazas, it's already soared past the Sunday after the holiday as the year's second busiest day.

At airports, train stations and toll facilities, officials are expecting a surge in the number of travelers as Thanksgiving continues its inexorable transition from a holiday to a holi-week.

At the same time the highways are becoming busier, downtown and other centers of office work show a distinct slowdown. The normal traffic jams on roads leading downtown decongest. Parking spaces become easier to find.

Kirby Fowler, president of the Downtown Partnership, becomes part of the trend each November when he heads up Interstate 95 to visit family.

"There is no way I'll drive on the Wednesday before Thanksgiving," he said. "Most recently we've been going up Tuesday afternoon getting a jump on things."

The Maryland Transportation Authority, which keeps meticulous statistics of the number of drivers passing through its toll plazas, reports that Tuesday departures are becoming increasingly popular along the Eastern Seaboard.

The numbers suggest that traffic on Monday will show a barely perceptible uptick from the typical November weekday. At three of the four toll facilities closest to Baltimore — the Bay Bridge, the Harbor Tunnel and the John F. Kennedy Memorial Highway — 500 to 1,000 more vehicles passed through the plazas on that day last year than on a typical November Monday.

It's Tuesday when the real surge begins.

Last year, 148,475 vehicles passed through Maryland's busiest toll facility, the Fort McHenry Tunnel, on Thanksgiving Tuesday. That's roughly 21,000 more than on the average November Tuesday and only 9,000 behind Thanksgiving Wednesday. The authority's other facilities show similar patters.

A spokeswoman for the authority, said shifting travel to Tuesday seems to be a trend.

At the seven toll facilities that were open last year, spokeswoman Teri Moss said, Wednesday led with about 426,000 travelers, while Tuesday was only slightly less busy at 383,000. Sunday came in a distant third at 325,0000.

Travel patterns are difficult to compare from year to year because of such variables as weather, economic conditions and even terrorist incidents. But a comparison of the figures from 2001 and 2010 show changes over the decade.

At the McHenry Tunnel, for example, Wednesday travel slipped from 160,672 in 2001 to 157,910 in 2010. But on Tuesday, tunnel travel grew from 140,666 to 148,475. The JFK Highway — I-95 northeast of Baltimore — showed a similar decline on Wednesday and growth on Tuesday.

At the Bay Bridge and Harbor Tunnel, both days showed increases, but the bump on Tuesday was greater.

Fowler said the trend is not just a Baltimore phenomenon.

"If you're traveling anywhere between D.C. and Boston, you need to get a jump on it," he said.

The toll authority official who oversees the JFK Highway said Thanksgiving Tuesday used to be just another day. But in the last few years, deputy administrator Sheila Williams said, the agency has beefed up staffing at its cash tollbooths to handle the increasing volume.

"It won't start before 11 in the morning," she said. "Eleven or 12 o'clock is when we first see it."