Smoke from wildfires in Canada is creating overcast skies and unhealthy air quality in parts of Minnesota, raising health concerns.

Wildfire smoke from Canada has made for bad air quality over parts of the Upper Midwest. Most of Minnesota had “unhealthy” air quality Saturday.

A fire near the Grand Canyon National Park in Arizona has grown more than 20 times in size in 24 hours as an intensifying wildfire season sees the return of Canadian wildfire smoke into the U.S.