Chicago air quality worst in the world today Crain's Chicago Business

Other Midwestern cities are experiencing heightened levels of air pollution today. Minneapolis ranks second on the WAQI list and Detroit comes in 10th — both unusually high.

Earlier this month, Chicago saw moderate levels of air quality and the Northeastern region of the U.S. was hit hard by another round of wildfire smoke.

Canada has been seeing its worst wildfire season in recent history with over 7 million hectares, or more than 17,000 acres, of land burned so far.

“As these unsafe conditions continue, the city will continue to provide updates and take swift action to ensure that vulnerable individuals have the resources they need to protect themselves and their families," Chicago Mayor Brandon Johnson said in a written statement. 

"This summer, cities across North America have seen unhealthy levels of air quality as a result of wildfire smoke, impacting over 20 million people from New York City, Washington DC, Montreal, and today here in Chicago. As we work to respond to the immediate health concerns in our communities, this concerning episode demonstrates and underscores the harmful impact that the climate crisis is having on our residents, as well as people all over the world," he continued. "We must take drastic action to mitigate these threats."

The Chicago Cubs, meanwhile, plan to open their gates at Wrigley Field tonight for a game against the Philadelphia Phillies despite the high level of air pollution.