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.
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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.
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.
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.
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 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.
-ABC News' Julia Jacobo, Max Golembo and Daniel Peck
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