WASHINGTON, DC — Ladies and gentlemen, start your engines: It's time to join the hordes of travelers out on the road headed out of town for Thanksgiving. And you'd better leave soon, or you'll regret it, because the worst day of Thanksgiving travel in the D.C. region is fast approaching.

Unfortunately, if you're still at home you've missed the best day to leave, which was on Sunday. But that doesn't mean your Thanksgiving trip to Grandma's house — or wherever you're going — has to be a bad one, as long as you keep in mind a few tips based on data from Google.

The absolute worst day for traffic is the day before Thanksgiving. And if you want to hit the worst traffic imaginable, leave at 3 p.m. on Wednesday.

In fact, leaving at 3 p.m. on any day this upcoming week is a bad idea. That's when most everyone will be looking to get out of work early and hit the roads.

The best way to make your trip smooth is to leave as early this week as possible, and as early in the day as possible. Plan a 6 a.m. or 7 a.m. departure regardless of which day you choose for the least amount of traffic.

What about the return trip? As much as you may want to sleep in after the big Thanksgiving feast, the best time to head back home is bright and early on Friday at around 6 a.m. Google data indicates that 4 p.m. is when traffic will be at its worst on that day.

The absolute worst day to depart is the Saturday after Thanksgiving, particularly at around 4 p.m. If you have to leave on Saturday, head out at 6 a.m.

And don't forget, be safe when you go out on these long trips: wear your seatbelt, observe posted speed limits, don't drive aggressively, be aware of your surroundings and never drink and drive.

Image via Wikimedia user Jumpy