(CNN) -- Call it a nation on the move, part two.
Barely a month after zipping across the country and back for Thanksgiving, millions of Americans are now making the annual trek for Christmas and New Year's.
If you're at an airport, you know: 'tis the season for travelers bearing presents and wearing Santa hats.
All eyes are on the weather, which could turn a simple journey into a nightmare before Christmas.
Take the hundreds of travelers who had to spend the night at Atlanta's Hartsfield-Jackson International Airport when severe storms swept through the city late Thursday and forced the airport to shut down for about three hours. The ground stop affected 5,200 flights, CNN's Holly Firfer reported.
"Always during the holidays you have a glut of people trying to get from point A to point B around the country, and very seldom does the weather cooperate perfectly," CNN meteorologist Reynolds Wolf said.
Winter storm warnings were in effect in parts of New Mexico, and strong winds could create whiteout conditions for drivers in the region, Wolf said. Meanwhile, a storm system could cause some travel problems in the Northeast.
Still, there were relatively few other weather trouble spots Friday morning, and most flights around the country were running on time.
The AAA projects almost 92 million people will travel 50 miles or more from home during the year-end holiday travel season, a 1.4% increase over last year.
The expected holiday travel volume represents 30% of the U.S. population.
"AAA is happy to learn so many Americans plan to travel this holiday season, contributing to the second-highest year-end holiday travel volume in the past decade," said Brent Hubele, vice president of AAA Travel.
The group defines the year-end holiday travel season as Friday through January 2.
The busiest days for fliers were expected to be between Wednesday and Friday, Monday through December 30 and then January 2 and 3 as travelers fly home, according to Airlines for America, the industry trade organization for the leading U.S. airlines.
Flying with food or gifts? Check out the Transportation Security Administration's guide to what you can and cannot bring through an airport security checkpoint. The agency reminds travelers not to wrap gifts they are carrying on planes because security officers may have to unwrap them if they need to take a closer look.
Fruitcakes are OK to bring along, but snow globes are not.
"Call us what you will (Grinch, Scrooge, Heat Miser), but ... they are sealed containers full of liquid that would have to be opened to test. We're not in the business of busting snow globes, so we suggest you place them in your checked baggage or mail them ahead of time," the TSA says on its blog.
The agency also offers tips on how to get through the security line faster, including packing coats and jackets in checked bags whenever possible and putting your shoes directly on the conveyor belt instead of a bin when they go through the X-ray machine.
If you're driving rather than flying and planning to go through an area that's expecting wintry weather, AAA recommends that you keep at least half a tank of gas in your car at all times and pack a cell phone, plus blankets, gloves, hats, food, water and any needed medication in case you're stranded.
Stay safe out there, and happy travels.