Weather

Toronto’s air quality ranked 3rd worst in the world as air quality warning issued for city

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Environment Canada is warning of poor air quality and reduced visibility in Toronto today due to wildfire smoke that has drifted into the region.

An air quality warning, yellow alert, has been issued for the city on Wednesday as smoke from forest fires in northwestern Ontario drifts south.

“Poor air quality may persist into Thursday for some areas,” the national weather agency said in its alert.

“As smoke levels increase, health risks increase. Limit time outdoors. Consider reducing or rescheduling outdoor sports, activities and events.”

As of about 6 a.m. on Wednesday, Toronto’s air quality was ranked 3rd worst in the world, according to IQAir, which tracks global air quality data.

“We have a very smoky start to the day. I know it may look like fog but we are contending with wildfire smoke,” CP24 Weather Specialist Jess Smith said on Wednesday morning.

“It doesn’t get better throughout the day today, unfortunately.”

Environment Canada said smoke may cause mild symptoms, such as eye, nose, and throat irritation, headaches or a mild cough.

“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,” Environment Canada said in its advisory.

Ontario weather alerts Environment Canada weather alerts across Ontario Wednesday morning, July 15, 2026.

Those at greater risk of health issues related to poor air quality include people over the age of 65, pregnant people, infants and young children, and people with existing illness or chronic health conditions.

“When indoors, keep windows and doors closed as much as possible,” the advisory read.

“When there is an extreme heat event occurring with poor air quality, prioritize keeping cool.”

Heat warning still in effect

A heat alert remains in effect for Toronto today with the mercury rising to 33 C today, feeling closer to 36 with humidity.

“We are still under that heat dome that stretches from southern portions of Saskatchewan through Manitoba, almost the entire province of Ontario, and into Quebec as well,” Smith said.

Environment Canada notes that the heat and humidity are exacerbating issues with air quality.

“Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category,” the national weather agency said.

“Watch for the early signs of heat exhaustion in yourself and others. Signs may include headache, nausea, dizziness, thirst, dark urine and intense fatigue. Stop your activity and drink water.”