WASHINGTON — This year’s Thanksgiving road trip rush on area highways was slowest the Tuesday evening before the holiday.

Data evaluated by the National Capital Region Transportation Planning Board was culled from anonymous traveler cellphones and navigation systems.

“A lot of time people fear what comes on Wednesday,” but Tuesday was worse, said transportation planner Ben Hampton. “We saw the average regional speed of traffic on freeways in the region drop to 26 miles per hour … around 6 p.m. on Tuesday.”

The information came from travel on highways and main artery roads roughly north to Frederick, Maryland; south toward Fredericksburg, Virginia; west along Interstate 66; and to the east toward Annapolis, Maryland.

On the Wednesday before Thanksgiving, area traffic flowed faster than on Tuesday, but backups began earlier — around lunchtime — with the slowest conditions occurring between about 3 p.m. and 4 p.m.

Looking at three years of data reveals inconsistent traveling conditions the day before Thanksgiving.

“Every year the speed profile for the day changed,” Hampton said.

Hampton believes individual crashes might contribute to the randomness of data for traveling on Wednesdays.

If you’re already thinking about plans for next year — Thanksgiving traffic moves really well in the metro area on Thursday, Friday and Saturday, the analysis found.