Heatwave in south and wildfire smoke in north buffet US from both sides

More than 80m Americans under air quality alerts while temperatures hit triple digits in south and south-west

Huge swaths of the United States continue to face extreme weather as temperatures persist into the triple digits in the south and south-west while smoke pollution is blighting the midwest.

Chicago and Detroit both had the most unhealthy air in the world for several hours on Tuesday evening, CNN reported, as smoke drifts from record Canadian wildfires. More than 80 million people, largely from the midwest to the east coast, are under air quality alerts.