Smoke from wildfires blazing across Canada is once again wafting over huge portions of the Midwest and worsening air quality, with conditions particularly bad on August 1 in Minnesota, Iowa and Illinois.

In central Utah, the Monroe Canyon Fire has burned 48,000 acres and is 7% contained as evacuation orders have been put in place. A total of 23 million Americans across six states are under heat advisories on Friday as heat indices between 105 to 110 are expected from Louisiana to South Carolina.