Millions of people in North America are under air quality advisories as wildfires burning across Canada have prompted evacuations, disrupted air travel and caused apocalyptic, smoke-filled skies even thousands of kilometres from the blazes.

The National Weather Service in the United States extended air quality alerts on Thursday for the East Coast from New England to South Carolina, as well as parts of the Midwest including Ohio, Indiana and Michigan.

Health officials in more than a dozen US states have also warned residents that spending time outdoors could cause respiratory issues due to the high levels of fine particulates in the atmosphere.

Canada is experiencing its worst-ever start to wildfire season on record, experts have said, with blazes reported in nearly all the country’s provinces and territories since May.

More than 400 Canadian wildfires are still burning, particularly in the eastern province of Quebec, where approximately 150 fires were reported as of Thursday morning and some 13,500 people have been forced to evacuate.

However, Quebec Premier Francois Legault said during an afternoon news conference that the situation was “stable” and no deaths or serious injuries had been reported so far.

He added, though, that it would take several more days before evacuees could go home.

“It’s still exceptional given the intensity of the fires [that], to date, no loss of life, no serious injuries. That’s what’s most important, so continue to be careful,” Legault told reporters in Quebec City.

Unhealthy air quality

The wildfires have brought orange-tinged skies to major Canadian and US metropolises, including New York City, where the iconic skyline was obscured earlier this week due to thick smoke and smog.

Briefly on Thursday, New York City’s air once again ranked more polluted than any major city in the world, reaching an overall reading of 178 on the Air Quality Index (AQI).

The AQI measures five major pollutants, including particulate matter produced by fires, and readings over 100 are classified as “unhealthy” while those exceeding 300 are “hazardous”.

On Thursday morning, several readings were over the 300-mark in the Washington, DC, area as well, prompting local health authorities to declare a “Code Purple” to warn residents of “very unhealthy air conditions” linked to the wildfires.

“Smoke from Canadian wildfires is causing unhealthy air quality in the Washington, DC area and the northeast US. This problem is likely to continue or worsen through Friday,” Mayor Muriel Bowser tweeted.

Al Jazeera’s Alan Fisher, reporting from Washington, DC, on Thursday afternoon, said “a milky haze” was still hanging over Capitol Hill.

“It’s going to be a couple of days before this starts to clear. At the moment, it’s stretching thousands of kilometres from Canada all the way down to South Carolina,” Fisher said.

Events cancelled

The haze and low visibility prompted aviation officials to halt incoming flights to major airports in New York and Philadelphia from the northeast and mid-Atlantic regions, as well as Ohio, for a second day on Thursday. All flights bound for the airport in Newark, New Jersey, also were delayed.

In Washington, DC, the White House pushed back its Pride Month event due to the smoke, and the Washington Nationals baseball team postponed its afternoon game, becoming the latest sporting event affected by the fires.

Smoky conditions are likely to persist until Sunday when a new storm system shifts the direction of prevailing winds, National Weather Service meteorologist Peter Mullinax said. It will also bring a chance of rainfall for parts of the US nearing drought conditions.

“We’re finally going to start to see more relief by the time we hit the early part of next week when we start to see those southerly winds come in and push that smoke more farther north and out into the Atlantic,” Mullinax said.

In the meantime, US President Joe Biden said his administration was ready to provide additional support to help Canada respond to the blazes.

The White House said in a statement that more than 600 firefighters and other personnel have been deployed to help their Canadian counterparts battle the flames, while further assistance was on the way.

“Yesterday I spoke with Prime Minister [Justin] Trudeau and offered any additional help Canada needs to rapidly accelerate the effort to put out these fires, particularly those in Quebec, where the fires are having the most direct impacts on American communities,” Biden said. (Al Jazeera)

•PHOTO: A man wears a protective face mask walking through Times Square in New York City as officials warn of poor air quality linked to wildfires in Canada on June 8, 2023 [Shannon Stapleton/Reuters]

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