If you’re planning on any air travel this summer, brace yourself for crowds. And if you’ll be traveling from New York City, the outlook just got worse: Some big airlines are cutting flights in and out of the Big Apple this summer.

JetBlue just announced that it will cut up to 10% of flights to and from the region. United and Delta plan to take similar steps, and other airlines could soon follow.

Why would major airlines cut flights in one of the busiest hubs in the country during what’s sure to be a very busy travel season? Because federal regulators asked them to. It’s all due to a shortage of air traffic controllers.

There are so many planes flying in and out of LaGuardia, JFK and Newark airports that landing slots are precious. In order to hold onto them, some airlines schedule more flights than they necessarily need.

The Federal Aviation Administration asked airlines to drop some of those flights, per Matthew Lehner, an assistant administrator at the FAA.

“What we said is that we need to have a bigger buffer,” he said. “And in New York, there’s a lot of international traffic that is coming back this summer that we didn’t have last summer.”

The bottom line? “There are just too many aircraft for the current FAA staffing levels, especially here in New York,” said Jason Rabinowitz, an aviation industry blogger.

Air traffic controllers have been in short supply for years, and the pandemic made the problem worse. While staffing has recovered a bit across the country, New York has just over half of the air traffic controllers it needs, according to the FAA.

And training new ones will take years, Rabinowitz said. “Really, it’s just how many people can they attract to this high-stress job as quickly as possible and get them trained up as quickly as possible,” he said. “And unfortunately, it seems like they haven’t been able to go as fast as anyone would have liked.”

The FAA says cutting flights in New York is a short-term fix and will make for a “smoother and safer summer.”

Still, the staff shortage could lead to more chaotic scenes at airports — especially if there’s bad weather, according to David Slotnick at The Points Guy.

“You could be delayed for hours, you might be delayed till the next day, whereas before, it was at least a little bit more predictable to know how the airlines were going to recover from everything,” he said.

So, maybe pack some extra snacks if you’re flying this summer. Oh, and if you’re looking for a job, the FAA is hiring.