Smoke from wildfires in Canada, along with fires burning in northern Minnesota, is spreading across much of the U.S. Midwest, Great Lakes, and Northeast, worsening air quality and reducing visibility. Multiple outlets report that haze is darkening skies in cities including Chicago and Detroit and is affecting commuter conditions along routes from the Great Lakes toward parts of the East Coast. U.S. air quality agencies issue alerts as conditions deteriorate to levels described as unhealthy to hazardous, with some reports citing AirNow readings reaching “hazardous.” Authorities in affected areas advise residents to limit time outdoors and reduce physical activity to lower exposure risk, particularly for people with respiratory or cardiovascular problems. One report notes that the scale of the impact reaches roughly 109 million people, while other coverage describes the alerts as spanning more than a dozen states, including parts of the Upper Midwest and Mid-Atlantic. Several outlets also note the presence of dozens of fires primarily in Ontario, and mention more than 180 active fires reported in Ontario as of Thursday. The smoke’s movement continues to depend on weather, with reporting focused on how long conditions may persist as it disperses.