Denver hit with worst air quality in the world as western wildfires continue to blaze

Denver recorded the worst air quality in the world on Saturday, as it was besieged with smoke from the Californian wildfires.

Residents were warned to wear a mask outdoors, avoid exercise, close windows and turn on air purifiers after the Colorado city recorded an air quality reading of 167 on Saturday, according to global pollution monitoring site IQAir.

Views of the Rocky Mountains were obscured by the thick dark clouds, the afternoon sun turned red, and the iPhone weather app informed Denver residents the weather on Saturday was “smoke”.