Canadian wildfire smoke is prompting air quality warnings in the western U.S.
![A smoky haze shrouds the high-rise buildings in downtown Denver on Saturday, May 20.](https://media.npr.org/assets/img/2023/05/21/ap23140749950199_wide-a7367eea5c24e391393978ebcf57aaa0ea9f3506.jpg?s=600)
Thick plumes of smoke from blazes in the Canadian province of Alberta crossed into nearby states including Montana, Colorado, Idaho and Utah.
(Image credit: David Zalubowski/AP)
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