A whole bunch of flights within the New York space have been delayed as smoke from a wildfire in Canada obscured visibility

Smoke from Canada’s wildfires blanketed New York City on Wednesday, June 7, 2023.

Leslie Josephs/CNBC

Smoke from wildfires in Canada delayed hundreds of flights at New York-area and Philadelphia airports on Wednesday as haze blanketed the region and obscured visibility.

The FAA had previously suspended flights to New York’s LaGuardia Airport for a short time.

“The agency will adjust traffic volumes to accommodate rapidly changing conditions,” the FAA said.

Smoke moving south from wildfires in Canada blanketed the New York City area Tuesday through Wednesday, affecting air quality and forcing residents indoors. As of Wednesday midday, the city ranked fourth in the world for the worst air quality, with an IQAir World Air Quality Index of 158, a level considered unhealthy for all residents.

Around 9:20 p.m. ET, more than 4,800 U.S. flights were delayed, according to flight tracking site FlightAware.

According to FlightAware, LaGuardia Airport had 230 departures, 40% of the day’s schedule, and 264 arrivals, or 46%, delayed. Nearly a third of flights into Newark Liberty International Airport were delayed, meaning 204 flights and another 186 departures were delayed.

Flights to LaGuardia were delayed an average of about two hours in the afternoon, and flights to Newark were delayed an average of 82 minutes, the FAA said. New York’s John F. Kennedy International Airport also reported both arrival and departure delays.

Almost 670 United Airlines Flights were delayed 24% of the timetable. Newark is one of the airline’s main hubs.

United said in a statement that they are “closely monitoring the situation, keeping an eye on the safety of our employees who work outside and adjusting our schedule where necessary.”

A speaker for Delta Airlines told CNBC that the airline has protective equipment in place for staff.

“And those working on the tarmac will be taken to the break rooms between aircraft rotations,” the spokesman said. “We are also monitoring the forecasts for rain in New York in the coming days, which should improve air quality.”

A American Airlines A spokesman said the company is making sure ramp workers have access to vehicles between flights, as well as other supplies such as water and masks.

— CNBC’s Emma Newburger contributed to this report.