Toronto air quality worst in world as Canadian wildfires spread smoke to US

Smoke from over 100 wildfires in Ontario, Canada, has caused Toronto's air quality to be ranked the worst in the world, turning skies yellow. The smoke is spreading into the US Midwest and Northeast, prompting health alerts for millions. Fueled by extreme heat and drought, the fires have forced evacuations of First Nations communities and disrupted events, raising concerns for the upcoming World Cup final in New Jersey.

Toronto air quality crisis

• ▪Toronto was also experiencing a heatwave, with temperatures reaching a record 37.3C (99F) on July 15, 2026
• ▪On July 15, 2026, air quality monitoring company IQAir ranked Toronto's air quality as the worst among major cities globally
• ▪Smoke from more than 100 wildfires in Ontario caused hazy, yellow skies over Toronto
• ▪Due to poor air quality, Toronto canceled outdoor events, including the FIFA Fan Festival for the World Cup semi-final
• ▪Environment Canada issued a "very high risk" Air Quality Health Index (AQHI) of 10+ for Toronto

Boundary Waters evacuation

• ▪In northeast Minnesota, officials closed the Boundary Waters Canoe Area Wilderness due to about 17 lightning-caused fires
• ▪The Canadian Air Force rescued two groups of youth campers from Minnesota who had crossed the border into a wildfire area in Canada
• ▪Rangers worked to evacuate an estimated 6,000 to 10,000 campers from the Boundary Waters Canoe Area Wilderness in Minnesota

Drought fueling wildfire spread

• ▪A Canadian National freight train near Armstrong, Ontario, was surrounded by flames, but the crew was safely rescued
• ▪As of July 15, 2026, there were 838 active wildfires burning across Canada, with 112 considered out of control
• ▪Research suggests that climate change, driven by burning fossil fuels, is making wildfires more frequent and intense
• ▪A heat dome over the central US is helping to drag the Canadian smoke south into the Midwest and Northeast
• ▪Severe drought, extreme heat, and dry conditions are fueling the wildfires in Canada
• ▪The Namaygoosisagagun First Nation community in northern Ontario was "devastated" by a fast-moving wildfire, forcing residents to evacuate

Smoke health risks

• ▪Wildfire smoke contains dangerous PM2.5 pollutants that can travel deep into the lungs or enter the bloodstream when inhaled

Safety guidance for residents

• ▪Experts suggest wearing an N95 mask when outside and using an air purifier or air conditioner indoors to improve air quality

US wildfire season scope

• ▪The 2026 Canadian wildfire season started more slowly than the record-setting 2023 season, when nearly 18 million hectares burned
• ▪The smoke is a concern for the World Cup final scheduled for Sunday in New Jersey, where over 80,000 people are expected to attend
• ▪Smoke from the Canadian wildfires prompted air quality alerts in multiple US states, including Minnesota, Wisconsin, Michigan, and New York
• ▪So far in 2026, Canadian wildfires have burned 1.9 million hectares (4.7 million acres)