(NEW YORK) — Hazy and dangerous fumes from ongoing Canadian wildfires have engulfed the skies over most of the Northeast coast, prompting serious air quality alerts.

Thirteen states have issued those alerts as the thick fumes block the sky and send people indoors.

Canadian officials said firefighters are scrambling to put out the blazes in Quebec, where more than 160 forest fires are currently active.

Here’s how the news is developing. All times Eastern:

Jun 07, 1:06 PM EDT
FAA slows NYC air traffic due to low visibility

Due to low visibility, the Federal Aviation Administration has slowed flight traffic in and out of New Jersey’s Newark Liberty International Airport and New York City’s LaGuardia Airport.

A ground stop is in effect at LaGuardia, meaning some flights are being held at their origin airport to ease congestion.

The average delay at Newark is about 84 minutes.

-ABC News’ Sam Sweeney

Jun 07, 11:32 AM EDT
Worst air quality yet may be headed to NYC

The worst air in the U.S. Wednesday morning is in upstate New York from Syracuse to Binghamton, where the air quality has reached the worst level — “hazardous.”

That air will move toward New York City and Philadelphia on Wednesday afternoon and evening.

Tuesday brought the worst air quality to New York City since the 1960s, officials said, with New York City Mayor Eric Adams calling it an “unprecedented event.”

The mayor urged New Yorkers to avoid going outside if they can.

Adams warned Wednesday, “Air quality conditions are anticipated to temporarily improve later tonight through tomorrow morning, but they are expected to deteriorate further tomorrow afternoon and evening.”

-ABC News’ Max Golembo

Jun 07, 10:19 AM EDT
Poor air quality will last into weekend for Toronto

In Toronto, the poor air quality will last into the weekend, officials warned Wednesday.

“Air quality and visibility due to wildfire smoke can fluctuate over short distances and can vary considerably from hour to hour,” officials said in a “Special Air Quality Statement.” “Wildfire smoke can be harmful to everyone’s health even at low concentrations. Continue to take actions to protect your health and reduce exposure to smoke.”

Jun 07, 9:32 AM EDT
NYC, DC public schools cancel all outdoor activities

Washington, D.C., public schools have canceled all outdoor activities, including athletic games, for Wednesday due to the poor air quality.

A “Code RED Air Quality Alert” has been issued for the nation’s capital.

New York City public schools also canceled outdoor activities.

“We urge everyone to reduce prolonged or heavy exertion outdoors,” NYC Public Schools tweeted.

Jun 07, 8:22 AM EDT
Long Island school district keeping students inside

In Port Washington, New York, on Long Island, the superintendent announced Wednesday that all students will stay inside during physical education and recess.

“This decision is aimed at minimizing exposure to the poor air quality and ensuring a safe learning environment for everyone,” the superintendent said.

Jun 07, 6:37 AM EDT
Air quality alerts issued for 13 states

Most of New England and much of the East Coast were under air quality alerts on Wednesday, with smoke from Canadian wildfires expected to reach as far south as South Carolina.

A new dose of very thick smoke was expected to drift into New York City and Philadelphia by Wednesday afternoon, lasting into the evening.

That smoke is then expected to move south into Washington, D.C., on Wednesday night and into Thursday morning.

Conditions around New York City and in the I-95 corridor could improve Thursday evening, but get worse in western New York, Pennsylvania and West Virginia, as the winds shift.

Jun 07, 12:49 AM EDT
NYC mayor says air quality expected to ‘deteriorate further’ Wednesday

The air quality in New York City worsened Tuesday evening and is expected to “deteriorate further” Wednesday afternoon and evening, New York City Mayor Eric Adams said in a statement.

“At this point, the New York State Department of Environmental Conservation has issued an Air Quality Health Advisory for all five boroughs. While conditions are anticipated to temporarily improve later tonight through tomorrow morning, they are expected to deteriorate further tomorrow afternoon and evening,” Adams said.

“Currently, we are taking precautions out of an abundance of caution to protect New Yorkers’ health until we are able to get a better sense of future air quality reports,” he said.

Adams said students should still go to school on Wednesday, but New York City public schools won’t have outdoor activities.

“These recommendations may change based on updated air quality conditions that come in, but, in the meantime, we recommend all New Yorkers to take the precautions they see fit to protect their health,” he added.

Jun 06, 10:09 PM EDT
Smoke from wildfires visible over Yankee Stadium

Smoke from wildfires from Canada was visible on Tuesday night over Yankee Stadium in The Bronx, as the Yankees played the White Sox, video obtained by ABC News shows.

Wildfires burning in Canada are continuing to create poor air quality conditions in parts of the U.S., with smoke clearly visible during Tuesday night’s Yankees-White Sox game in The Bronx. https://t.co/yhKArhnaNt pic.twitter.com/Np8mJyVKCa

— ABC News (@ABC) June 7, 2023

Jun 06, 10:01 PM EDT
New York City currently has the worst air quality in the world, data shows

New York City currently has the worst air quality than any other city on Earth, as smoke stemming from wildfires in Canada makes its way across the Northeast, according to the latest data from Swiss technology company IQAir.

The air quality index in NYC is at 196 as of Tuesday evening, followed by Doha, Qatar, and Delhi, India.

The next U.S. city on the list is Detroit, which currently places eighth, according to IQAir. Toronto, Canada, sat in ninth place as of Tuesday night.

Jun 06, 11:00 PM EDT
Who is at most risk from unhealthy air

The U.S. Environmental Protection Agency has specific guidance for vulnerable groups if the air quality in their area is deemed “unhealthy.”

While the agency warns that all people will experience adverse side effects from exposure to the unhealthy air, it said those with heart or lung disease, pregnant people, children and the elderly are most sensitive.

Those groups should consider moving all of their activities indoors until the air quality alert is lifted, the EPA said.

Jun 06, 11:02 PM EDT
Northeast covered in haze as forecasters warn of more smoke to come

Millions of people in New York City and other locations in the Northeast scrambled to keep themselves free of the smoky air throughout the day and evening Tuesday.

The city’s skyline was barely visible for most parts of the day, and the smell of the smoke was strong as commuters hit the evening rush.

Large cities with the lowest air quality include New York City; Albany, New York and Cincinnati, a map by Airnow, a website that publishes air quality data, shows.

Another large and dense plume of smoke will be moving down across parts of the Northeast on Wednesday, according to forecasters.

That batch of very dense smoke will push down across the Northeast throughout the day on Wednesday, giving some relief to New England and the Midwest.

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