Smoke from wildfires still raging in Canada is degrading air quality across the northern US, turning skies a murky orange hue and forcing sensitive groups indoors. In New York, the smoke could be seen in the upper atmosphere from satellites. Poor air quality also plagued the city of Chicago, and residents were told to reduce time spent outdoors. Forecasters said there’s a chance an alert there would be extended into Friday, as temperatures across much of the eastern US continue to spike ahead of a rainy weekend.

Wildfire smoke is made up of chemicals, carbon monoxide and particulate matter. The particle pollution can affect the eyes, throat, lungs, and heart. Sometimes, it can even lead to premature death. “It’s probably a good idea to limit time outside,” Kevin Doom, a meteorologist with the National Weather Service, said, according to The Chicago Sun-Times. “Doing a lot of heavy breathing is probably not ideal on a day like today.”

Canada's deadly fires have resulted in the deaths of two people and forced tens of thousands of people to flee. Officials in Mantiboa and Saskatchewan have declared a state of emergency. Manitoba skies have turned a ruby red color. “I've never seen anything like it,” Saskatchewan Premier Scott Moe said, according to CBC News.

Smoke fills the air over Chicago this week. The city is home to more than 2.6 million residents (Getty)

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Julia Musto

U.S. Science and Climate Correspondent | ‪@juliaelenamusto.bsky.social‬

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