Impact of Canadian Wildfires
On Wednesday, smoke from wildfires raging in Canada drifted into the northeastern United States, causing hazy and yellow skies in cities such as New York and Boston. This situation has led to air quality alerts being issued across multiple states. Officials have cautioned that the smoke may spread further throughout the week, exacerbating health risks, especially as the region is also experiencing a severe heatwave. According to AccuWeather, this smoke event mirrors the significant wildfire incident in Canada from 2023, when smoke from Quebec enveloped much of the northeastern US for several days.
Details on Canada Wildfires
Details on Canada Wildfires
More than
800 wildfires are currently active across Canada, with many out of control in western Ontario. Reports indicate that over 100 wildfires in northern Ontario have turned Toronto's skies yellow, resulting in the city having the worst air quality globally on Wednesday, as per IQAir.
Dramatic footage from near Armstrong, Ontario, depicted a train crew surrounded by flames, but Canadian National confirmed that the crew was safely evacuated. Toronto is also facing an intense heatwave, with temperatures in the downtown area reaching 37.3°C and runway temperatures at the main international airport soaring to 55°C.
Air Quality Alerts in the US
Air Quality Alert in The US
The smoke has spread across the Great Lakes and Northeast, prompting air quality alerts from Wisconsin and Michigan to New York and Massachusetts.
NOW: Smoke is blanketing New York City as pollution from Canadian Wildfires spreads over the Northeast.Notify NYC issued an Observed Air Quality Health Advisory on July 15, 2026 at 01:02 PM:"The Air Quality Index in all or part of New York City has reached Level Red (AQI… pic.twitter.com/zA3LZowV6l
— Oliya Scootercaster 🛴 (@ScooterCasterNY) July 15, 2026
In New York City, the state Department of Environmental Conservation and Department of Health issued an Air Quality Health Advisory for New York City and Long Island until at least 9 PM Wednesday. Officials have warned of potential worsening air quality, although the timing and extent of ground-level smoke impacts remain uncertain. The National Weather Service has also indicated that nearly 100 million people across the US are under "major" or "extreme" heat warnings as the smoke coincides with an ongoing heatwave. New York City is expected to reach 99°F, with health officials advising residents to remain indoors in cool, air-conditioned environments. Boston recorded an Air Quality Index (AQI) of 147 on Wednesday morning, categorizing it as "unhealthy," with little improvement anticipated into Thursday, according to AccuWeather. Forecasts suggest that dense smoke will further expand on Thursday, affecting much of the Great Lakes and New England, including Detroit, Cleveland, New York, and Philadelphia, while hazy conditions will spread across much of the northern United States. Toronto's AQI reached 220, classified as "very unhealthy." Health officials have cautioned that sensitive groups may experience immediate health effects, while healthy individuals could face breathing difficulties and throat irritation. Authorities have advised limiting outdoor activities, particularly for sensitive groups, as smoke exposure can lead to respiratory issues, throat irritation, and itchy eyes. Residents are also encouraged to keep pets indoors to minimize their exposure to poor air quality.