More Canadian wildfire smoke shrouds US midwest, mid-Atlantic and north-east

109 million people face another day of poor air quality as smoke from blazes in Ontario drifts over the US

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Tens of millions of Americans face another day of smoky skies, irritated eyes and bad air quality, as Canadian wildfire smoke spread again over huge swathes of the US, affecting around 109 million people across the midwest, mid-Atlantic and north-east.

The pungent wildfire blanketed cities such as https://www.theguardian.com/us-news/chicago">Chicago and https://www.theguardian.com/us-news/detroit">Detroit, where residents on Friday were warned to stay indoors and reduce activity levels after the air quality index reached a “hazardous” 361, according to the government website https://www.airnow.gov/?city=Detroit&state=MI&country=USA">AirNow.