Blazes across several Canadian provinces and territories pose health risks to Canadians and their southern neighbours.
Smoke from wildfires burning in Canada has triggered air quality alerts over the border in the United States.
Several blazes continued to rage across Canada on Saturday, sending smoke wafting over several states in the US Midwest and bringing warnings of unhealthy air for at least the third day.
Air quality alerts were in effect in the US states of Iowa, Minnesota, Wisconsin and Michigan, as well as eastern Nebraska and parts of Indiana and Illinois.
Conditions were especially dire in Minneapolis, Minnesota, with the Switzerland-based air quality monitoring database IQAir reporting that the US city had some of the worst air pollution in the world since Friday.
The Air Quality Index (AQI), a system used to communicate how much pollution is in the air, is expected to reach the red or unhealthy category in a large swath of Minnesota, and will likely remain so through Saturday.
“We’ve sort of been dealing with this, day in and day out, where you walk outside and you can taste the smoke, you can smell it,” said Joe Strus, a meteorologist with the National Weather Service in the Minneapolis–Saint Paul area.
Forecasters warned that smoky skies would remain across the Midwest for much of Saturday, but could start to dissipate before spreading as far south as Tennessee and Missouri.
The poor air quality poses particular risks for people with lung and heart conditions, as well as children, the elderly and pregnant women.
This is not the first time that Canadian wildfires have prompted air quality alerts in the US and further afield. In 2023, a record early wildfire season sent smoke across the Atlantic into northern Europe.
On Saturday, the Canadian Interagency Forest Fire Centre reported “out-of-control” blazes in the provinces of British Columbia, Alberta, Saskatchewan, Manitoba and Ontario, as well as in Yukon and the Northwest Territories.
The centre said that 717 fires were active across the country.
Environment Canada also said “extremely high” levels of air pollution were present in Saskatchewan, Manitoba, Ontario and the Northwest Territories, according to a report by The Canadian Press news agency.
Areas in British Columbia, Alberta and Quebec were also under air-quality watch, though risks to health were reportedly lower.
Environment Canada said reduced visibility and poor air quality would persist into Sunday.