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.

Notably, there are also fire weather concerns for parts of Hawaii, specifically the leeward portions of all Hawaiian Islands and interior sections of the Big Island as dry weather, as well as wind gusts between 35 and 50 mph, will persist through the weekend with conditions improving by late Sunday for the Hawaiian Islands.

The Iowa Department of Natural Resources reported Friday that air quality in Iowa will be at levels “unhealthy for sensitive groups” through Saturday, due to smoke from wildfires in Canada. The National Ambient Air Quality Standards advise that fine particulate matter should not exceed averages of 35 micrograms per cubic meter in a 24-hour period.