Smoke from Canadian wildfires affects air quality, skies in Northeast U.S.

Waterloo Region’s air quality among world’s worst

Toronto air quality ranked worst in the world as wildfire smoke settles in

Chicago battling high heat, poor air quality

Chicago battling high heat, poor air quality

Toronto is choking: Wildfire smoke has created the world's worst air quality

Toronto air quality ranked the worst among major cities globally

Toronto Has the Worst Air Quality in the World | Your Morning

Chicago weather: High temperatures, Air Quality Alert in effect for area

Toxic wildfire smoke threatens millions

State of emergency declared in West Virginia amid warehouse fire

Southern Ontario air quality forecast: Here's how long the smoke could last

View of downtown Toronto as wildfire smoke blankets city

Canadian wildfire smoke returns to Michigan, prompting statewide air quality alert