Air alerts in 17 states from Canadian wildfire smoke

Air quality alerts remained in effect across at least 17 U.S. states on Thursday, July 16, 2026, as dense smoke from hundreds of Canadian wildfires blanketed the Midwest and Northeast, creating hazardous conditions from Minnesota to Virginia. Major cities including Detroit, Minneapolis, Chicago, and New York City recorded some of the worst air pollution levels in the world, prompting urgent health warnings for millions of residents.

The smoke, originating from over 800 active wildfires in Canada, was carried south by atmospheric conditions, with over 100 fires burning out of control. Federal monitoring showed air quality indices reaching "unhealthy" to "hazardous" levels across the affected region. Detroit recorded an extreme AQI near 600, placing it in the most severe "hazardous" category and ranking it as the major city with the poorest air quality globally on Thursday. Minneapolis and Toronto also ranked among the world's most polluted cities.

In New York City, the Air Quality Index reached the "unhealthy" Level Red, with conditions forecast to potentially worsen to "very unhealthy" later in the day. Officials noted that the city's pollution levels briefly surpassed those of...