An air quality warning was lifted for Toronto following a day of thick smoke caused by northern Ontario wildfires, but conditions were still improving as of Tuesday.
The national weather agency says smoke was expected to cause poor air quality and reduced visibility, which could persist through the day and possibly into Tuesday for some areas.
At noon on Monday, Toronto’s air quality index of 174 was second-worst in the world behind only Baghdad, according to IQAir. Environment Canada listed Toronto’s air quality health index at 10+, indicating “very high risk.”
It has since improved, but as of 5 a.m. on Tuesday, Toronto’s air quality was the eighth-worst in the world, per IQAir. Environment Canada now has it listed as a 5 on its scale (moderate risk).
Environment Canada continues to urge residents—particularly vulnerable groups—to take extra precautions.
Those most at risk from wildfire smoke include people aged 65 and older, pregnant individuals, infants and young children, those with existing illnesses or chronic health conditions, and people who work outdoors. Officials recommend that these groups avoid strenuous outdoor activities and seek medical attention if they experience symptoms such as coughing, difficulty breathing, or chest discomfort.
“You may experience mild and common symptoms such as eye, nose and throat irritation, headaches or a mild cough,” Environment Canada said. “More serious but less common symptoms include wheezing, chest pains or severe cough. If you think you are having a medical emergency, seek immediate medical assistance.”
Much of Central Canada, Manitoba and Saskatchewan were placed under special air quality statements or warnings on Monday due to smoke from wildfires on the Prairies and northern Ontario.
For Randy Mitchell and his co-workers at a downtown Toronto construction site, staying out of the smoky air was a challenge on Monday.
Even though the crew working on a new subway line was encouraged to take breaks indoors, Mitchell said someone still had to be on each corner of the site at all times.
“It’s very humid, very humid right now,” he said. “The breathing quality is just … it’s horrendous.”
A heat warning remains in place for Toronto after being issued over the weekend. Residents can find relief from the heat and humidity at more than 500 cool spaces across the city, including libraries, community centres, and air-conditioned civic buildings.
Brace for hazy 48 hours
Ongoing wildfires in Saskatchewan, Manitoba, and northwestern Ontario continue to produce massive plumes of smoke that are actively filling the atmosphere. Since Jan. 1, 2025, more than 3,000 wildfires have burned over 5 million hectares across the country.
Today’s daytime high in Toronto reached 31 C on Monday, with the humidex values in the upper 40s.
The City has extended pool hours until 11:45 p.m. at Alex Duff, Fairbank, Halbert (until 9 p.m.), McGregor, Monarch, Smithfield, and Sunnyside due to the extended heat warning.
A scorcher is forecast for Tuesday with sunny skies and a daytime high of 32 C. The humidex is likely to reach 37 in Toronto on Tuesday, Environment Canada says.
Daytime temperatures could drop slightly by mid-week or Thursday, when cloudier conditions and the potential for rain move in. There is a 60 per cent chance of showers for Toronto on Thursday, with a daytime high of 29 C.
Toronto residents could get a break from the extreme heat by the end of the week, when daytime temperatures could drop to a high of 25 C.
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