Wildfire smoke snarls East Coast flights for a second day

The Federal Aviation Administration on Thursday began slowing flights in the New York City area for a second day, as Canadian wildfire smoke continues to impact visibility on the ground.

As of 10 a.m. Thursday, the FAA delayed all inbound flights to Newark Liberty International Airport and paused incoming flights from the Northeast, Ohio and mid-Atlantic to LaGuardia Airport and Philadelphia International Airport.

So far the amount of delayed flights is relatively small — 57 at Newark and 73 at LaGuardia as of Thursday afternoon — but those numbers could climb.

"If there's good news, it's that this has led to relatively few cancellations," DOT Secretary Pete Buttigieg said on MSNBC. "We have been able to keep the system going through ground delay programs, but certainly, if you're planning a trip today or in the next few days, you want to keep a close tab on the airline information...because it's likely if you're going through these affected airports that those delays are going to affect you."

The FAA also cautioned that other East Coast airports could face delays on Thursday.

"The FAA will likely need to take steps to manage the flow of traffic safely into New York City, DC, Philadelphia and Charlotte due to reduced visibility from wildfire smoke," the agency said in a statement.

FAA spokesperson Kevin Morris explained that wildfire smoke causes more delays than fog or rain because the air is filled with solid material instead of liquid, which makes navigational equipment on planes and on the ground less effective. Because of that, the FAA is requiring greater distances between arriving and departing flights along with limiting certain types of aircraft that can land, which leads to delays.

"When aircraft need to land during periods of poor visibility, these systems work well through water droplets but can be less effective through solid particles such as smoke and ash," Morris said.

The smoke is the latest curve ball for the summer travel season, as airlines and the FAA brace for record travel levels from June through August.

Flight delays at Newark were averaging about 35 minutes while flight delays at LaGuardia are close to an hour, the FAA said.