More than 100 active wildfires in northern Ontario have sent thick smoke drifting across Toronto and into the north-east United States, including New York City. The smoke blanketed the skyline of Canada's largest city, turning the sky a sickly yellow.
On Wednesday, Toronto recorded some of the worst air quality of all major cities worldwide. Air quality monitors ranked the city as having the worst air quality on earth, surpassing New Delhi, India, and Kinshasa, DR Congo.
Environment Canada issued health warnings as authorities urged residents to stay indoors to avoid the smoke and extreme heat. The smoke-shrouded skies have already caused allergic reactions for many people.
The National Weather Service stated that the smoke from these wildfires could linger into the end of the week.