Rampaging Wildfire Impacts Air Quality and Brings Devastation to Ontario

On Wednesday, July 15, 2026, thick smoke from hundreds of wildfires in northwestern Ontario drifted south. The smoke also spread into New York City and across the northeastern United States.

As Toronto residents woke up to an orange sky and a strong smell of smoke, air quality monitors showed “very high risk” levels, indicating the air was dangerous to breathe. Environment Canada, the Canadian federal weather agency, issued a health warning, urging people to stay indoors.

“So far this year, about 4.7 million acres of forest have burned,” across Canada. That is, “less than a quarter of the 22.2 million acres that burned in 2025,” which was the second-worst year on record. The worst year was 2023 with a comparable amount of destruction.

The fires are being fueled by a “heat dome,” a high-pressure system that traps hot air over a region. On Tuesday, temperatures in Toronto reached 99°F (37°C). The heat and dry conditions helped the fires grow and kept the smoke close to the ground. Meteorologist Brian Proctor from Environment Canada stated the smoke would “likely get worse before it got better over the following 36 hours.”

At one point on Wednesday, July 15, IQAir, a Swiss company that tracks air pollution, ranked Toronto as the most polluted major city in the world, making July 2026 one of the most polluted months of Toronto.

More than 100 fires were burning in the region, and several rural and Indigenous communities were forced to evacuate. One of them was Collins First Nation, a small community of about 40 residents. Members escaped by boat as flames destroyed homes, a school, and community buildings. Sol Mamakwa, an Indigenous member of Ontario’s parliament, said the fire had, “erased,” the community. (The New York Times) The Ontario government requested federal assistance, and Prime Minister Mark Carney pledged support.

The fires also threatened trains that were carrying flammable cargo. The Ontario Provincial Police said three trains were held in safer locations to keep them away from the flames. A video from inside a train cab showed engineers watching flames rush through trees near the tracks. The crew was safely evacuated, and rail operations in the area were suspended.

Air quality officials warned that hazy, smoky conditions were expected to continue through the end of the week across Ontario and the northeastern United States.

Works Cited:

Canadian Interagency Forest Fire Center. “National Fire Situation Report.” CIFFC, 15 July 2026. https://ciffc.net/situation/2026-07-15.

Environment Canada. “Air Quality Health Index.” Government of Canada, 15 July 2026. https://www.iqair.com/ca/air-quality/canada/ontario/toronto.

Isai, Vjosa. “Wildfires Rage in Ontario as Smoke Affects Toronto’s Air Quality.” The New York Times, 15 July 2026. https://www.nytimes.com/2026/07/15/world/canada/wildfire-smoke-toronto-ontario-northeast.html.

Cecco, Leyland. “Wildfires in Ontario make Toronto air quality worst in world.” The Guardian, 15 July 2026. https://www.theguardian.com/world/2026/jul/15/wildfires-in-ontario-make-toronto-canada-air-quality-worst-in-world.