Chicago records second-worst air quality in the world as Canadian wildfire smoke returns to the Midwest and Northeast.

Chicago recorded an Air Quality Index of 128 on Sunday evening, ranking as the second-worst air quality among major cities worldwide. The Environmental Protection Agency reported that the smoke, primarily driven by active wildfires in Ontario, Canada, and northeastern Minnesota, created unhealthy conditions for sensitive groups including children and the elderly. The region has faced a volatile week of air quality. While Chicago recently saw record-breaking pollution levels that forced the closure of beaches and outdoor pools, a brief reprieve was interrupted by the return of dense smoke. Experts attribute the persistent haze to a heat dome trapping pollutants near the ground and a jet stream dip carrying smoke southeastward. While some areas like New York and Washington, D.C., saw improvements following weekend storms, the Midwest and Northeast continue to face alerts. Forecasters suggest that while some rain may provide temporary relief, significant air quality improvements may not occur until the colder weather season arrives. Residents are advised to wear N95 masks and keep windows sealed to mitigate the health impacts of the lingering smoke.

Sources