Wildfire smoke and air quality updates: Northeast flights disrupted

Air quality alerts have been issued for states across the Northeast.

Hazy and dangerous fumes from ongoing wildfires in Canada have engulfed the skies over much of the East Coast, prompting serious air quality alerts in over a dozen states.

Canadian officials said firefighters are scrambling to put out the blazes. So far this wildfire season, Canada has seen more than 8.7 million acres burned -- an area larger than the state of Vermont.


Latest forecast

The large plume of hazardous wildfire smoke that moved through New York City on Wednesday drifted into the Mid-Atlantic Thursday, bringing dangerous air conditions to Philadelphia, Baltimore, and Washington, D.C.

By Thursday night, the thickest smoke will continue to spread over the Mid-Atlantic. AQI values may reach 400 in some areas. (Levels under 100 are generally considered safe.)

By Friday morning, the hazardous haze will be covering Pittsburgh and the Chesapeake Bay.

The smoke may thin out during the day on Friday with cities like New York City seeing clearer conditions by Friday evening.

Major relief will move in by Monday when a cold front sweeps across the East, washing away much of the smoke in the air.

-ABC News' Daniel Amarante


NYC extends Air Quality Health Advisory until Friday night

New York City's Air Quality Health Advisory has been extended to Friday night.

While the AQI in New York City has been dropping significantly throughout the day, as of Thursday afternoon it registered at 178, which is still considered unhealthy.

Totals were over 400 in New York City on Wednesday. Levels under 100 are generally considered safe.


NYC schools will be remote on Friday

Learning will be remote on Friday for New York City public schools.



What you need to know about the dangers of inhaling wildfire smoke

Air quality is measured by the Environmental Protection Agency’s air quality index (AQI), which ranges from 0 to 500. A higher level indicates a greater level of pollution and health concern.

Levels under 100 are generally considered safe.

Totals were over 400 in New York City on Wednesday.

Click here for more information.


How to stay safe from wildfire smoke

The most effective way to protect yourself during wildfire emergencies is to stay indoors or limit time outdoors when there is smoke in the air, according to the Centers for Disease Control and Prevention. This is especially important for those with heart or lung conditions who are at higher risk for adverse health effects.

If you can, try to avoid exercising outdoors until the air quality improves, especially those with underlying lung disease.

"People with asthma and people who already have lung disease or underlying lung problems, it can exacerbate that, it can irritate that. And if the air quality is bad enough, it can even cause some symptoms of feeling unwell and respiratory symptoms in people who are healthy," said Dr. Stephanie Widmer, a member of ABC News' Medical Unit.

Pregnant people should also try to avoid spending time outdoors, especially those who are further along, Widmer said.

You should wear a mask that covers your nose and mouth, fits tightly to your face and can filter out smoke or ash particles before you breathe them in, according to the CDC. N95 or P100 masks can help protect your lungs from smoke or ash.

Click here for more tips on how to stay safe.

-ABC News' Nadine El-Bawab and Youri Benadjaoud