Canadian wildfire smoke chokes US air, triggering alerts in over 20 states

Wildfire smoke billowing from Canada has blanketed large swaths of the United States, triggering air quality alerts in over 20 states and exposing millions to unhealthy and even hazardous air conditions. The smoke originates from more than 180 active wildfires burning in southern-central Canada and parts of Minnesota.

On Wednesday, the smoke briefly made Toronto's air quality among the worst globally. By Thursday morning, the haze had spread significantly across the U.S. Northeast and Midwest. NASA reported that prevailing winds carried smoke from Ontario fires southeastward, tinting skies gray, yellow, and the sun orange in affected areas.

Air quality alerts have been issued across numerous states, including New York, Pennsylvania, Ohio, Michigan, and Wisconsin. In several parts of these states, air quality is rated "unhealthy," "very unhealthy," or "hazardous." Officials are urging residents to reduce outdoor activity and stay indoors, particularly vulnerable populations.

Detroit, Michigan, was listed as having the worst air quality in the world on Thursday morning, according to IQAir's global rankings, followed closely by Toronto, Minneapolis, and Chicago. The National Weather Service warned of reduced visibility due to dense smoke, especially in the afternoon and evening.

New York City officials extended the city's heat emergency plan, incorporating cooling centers due to the combined threat of high temperatures and poor air quality. Mayor Zohran Mamdani advised residents to remain in air-conditioned spaces and stay hydrated. Governor Kathy Hochul announced the distribution of over 100,000 N95-style masks to counties in need and at major transit hubs.

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It’s dangerously hot and smoke from Canadian wildfires has worsened our air quality, which means New Yorkers need to be extra vigilant to stay safe