As holiday travel rush ramps up at Tri-State Area airports, experts warn to expect the unexpected

If you're flying out for the holidays, this is the time when airports flip the switch from busy to brutal. 

Millions of travelers will be moving through Newark Liberty International Airport over the course of just a few days.

Saturday evening was the start of the holiday travel rush. Airlines are bracing for some of the heaviest travel days of the season, especially in the days right before Christmas, with planes expected to be full and very little wiggle room if something goes wrong.

Experts say the real takeaway this year is that there could be fewer backup flights, so when something slips, it tends to slide fast.

"This is a really busy season, and it's not your normal Tuesday travel, you know, in September," said Jordan Bykowsky, with United Airlines. "Expect the unexpected. With us here, I would say the only thing we're just thinking about is weather. But that's something we deal with honestly every day throughout the year, so it's not anything that we can't handle."

Other airlines like American and Delta say they're staffed up, in some cases using bigger planes where possible, and leaning hard on their apps to keep travelers informed.

AAA projects more than 8 million people will fly domestically over the course of the next few days, up 2.3%  from last year. They also say Saturday and Sunday are considered to be the busiest days to fly.

Experts say watch the weather nationwide, not just locally. When booking, give yourself time between connections, and don't assume a flight that's on-time now will stay that way.