Canadian wildfires in Ontario have triggered mass evacuations and sent hazardous smoke across parts of the US and Canada, causing unhealthy air quality, health warnings, and precautionary measures in cities including New York, Chicago, Detroit, Minneapolis, and Toronto.
A Canada Goose stands on the shoreline of the Toronto Islands, on Lake Ontario, as the downtown skyline is covered by wildfire smoke in Toronto, Ontario, Canada, Jul 15, 2026. (Photo: REUTERS/Kyaw Soe Oo)
17 Jul 2026 12:39AM
MONTREAL: Out-of-control wildfires were raging Thursday (Jul 16) in the Canadian province of Ontario, prompting evacuations and sending dangerous smoke billowing into the United States where millions of people were exposed to the unhealthy air.US states near the Canadian border including Minnesota, Wisconsin, Michigan and Illinois were particularly choked, as forecasters predicted the Northeast including New York would also see air quality continue to deteriorate.On Thursday morning, tracker IQAir listed Detroit, Toronto, Minneapolis and Chicago as the most polluted cities in the world.A hazy cast hung over New York where forecasters expected the densest strip of smoke to cloud the region into the afternoon.A New York state air quality health advisory warned of fine particulate matter from the fires that would make the outdoors "unhealthy" for everyone across the New York metro area and Long Island, with even worse conditions in the central and western regions of the state.Authorities encouraged New Yorkers to spend as little time outside as possible.Mayor Zohran Mamdani warned that "the combination of dangerous heat and unhealthy air is a serious threat."Libraries and train stations were offering free masks, while hundreds of cooling centres were open across the city for those without access to air conditioning."This could become the most significant smoke event in New York City since 2023, and conditions will be closely monitored for any deterioration," the city's Department of Emergency Management said.That year, the city's skies turned an apocalyptic orange, and the air quality index reached a hazardous 465.
