6:50 p.m. update: President Trump has arrived at Mercedes-Benz Stadium, Channel 2 Action News reports. Atlanta traffic is returning to normal.

6:30 p.m. update: President Trump's motorcade is already inside the Perimeter, and I-75 is reopening as it passes, Channel 2 Action News reports.

6:05 p.m. update: President Donald Trump has touched down at Dobbins Air Reserve Base in Marietta. That means traffic is about to get complicated. Channel 2 Action News reports that I-75 has been closed from Marietta to downtown to accommodate the president's motorcade.

5:24 p.m. update: Traffic remains light for rush hour on metro Atlanta highways. But it's not likely to last.

The gates of Mercedes-Benz Stadium are now open, and tens of thousands of fans will descend on downtown over the next few hours.

What’s more, President Trump is preparing to depart Nashville for Atlanta. He’ll land at Dobbins Air Reserve Base in Marietta. Then the presidential motorcade will make its way to the stadium.

For security reasons, the Georgia State Patrol has not released specifics of when and where roads will be closed for the motorcade.

Though it’s a light rush hour, two accidents have shut lanes on I-20 east of the city. The HOV lane and two left westbound lanes are blocked at Candler Road in DeKalb County. Two right westbound lanes are blocked at West Avenue in Rockdale County.

Original post: Metro Atlanta avoided a winter-weather traffic mess Monday morning. But the day's biggest traffic headaches are still to come.

Tens of thousands of fans will pour in to downtown this afternoon and evening to watch Georgia and Alabama compete for the college football national championship. And President Donald Trump's motorcade likely will lead to a series of rolling road closures at rush hour.

Georgia Department of Transportation spokeswoman Natalie Dale said the game will generate higher-than-usual traffic downtown. Most fans for both teams are within driving distance, and Dale said many people will show up just to be part of the championship atmosphere, even if they don’t tickets.

“This is more than a football game,” she said. “I would venture to say you don’t have a lot of people going down to Mercedes-Benz Stadium just to hang out if they’re not going to the Falcons game. This is totally different.”

One thing that will help: Many schools and government offices are closed today. But GDOT expects vehicle and pedestrian traffic to be heavy. The agency will monitor traffic and adjust signals to keep it flowing as smoothly as possible, Dale said.

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The AJC's David Wickert keeps you updated on the latest in what's happening with transportation in metro Atlanta and Georgia. You'll find more on myAJC.com, including these stories:

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