State forecasters say outdoor air will be unhealthy for vulnerable people again this weekend, with a new wave of Canadian wildfire smoke pushing south into Minnesota.
More Canadian smoke will arrive in Minnesota Friday and Saturday, could linger Sunday
The Minnesota Pollution Control Agency said it's likely they will extend a roughly 36-hour warning for wildfire smoke.
July 13, 2023 at 7:23PM
A forecast from the Minnesota Pollution Control Agency said that the entire state should expect air quality index readings in the orange category starting at 8 a.m. Friday through 3 p.m. Saturday. This category, from 101 to 150 AQI, means the pollution in the air is harmful for young children, the elderly, and anyone with breathing difficulties, like those with asthma or COPD.
Nick Witcraft, an air quality meteorologist with the agency, said he expects the warning will be extended for part of the state into Sunday, but it's too soon to know exactly where the smoke will linger.
MPCA forecasts in 24-hour averages, meaning that the level of pollution can swing higher or lower from hour to hour during a smoke incursion. Witcraft said it was "certainly a possibility" that AQI could reach the red category in some areas, meaning the air is unhealthy for everyone.
The primary pollutant from wildfire smoke is fine particles, abbreviated as PM 2.5, which can burrow deep into the lungs and cause damage. Health authorities say people should limit outdoor activity to reduce exposure to the pollution and run indoor air conditioning to recirculate. Only tight-fitting N95 respirators are effective in filtering smoke particles.
Fires continue to burn across Canada, despite a wave of rains in the past week that dropped as much as a month's worth of precipitation and unleashed flooding on parts of southern Quebec, the CBC reported. Since May, more than 36,000 square miles of the country have burned, according to the Canadian Interagency Forest Fire Centre — an area that would cover two-fifths of Minnesota.
The latest smoke expected to reach Minnesota is wafting from British Columbia and Alberta, MPCA forecasts said. Canada's largest priority fire — the Donnie Creek fire — is burning out of control in northern British Columbia, covering some 2,250 square miles, according to the BC Wildfire Service.
“This was certainly not an outcome that we were hoping would materialize, and we know that today’s path forward does not provide a perfect solution,” interim OCM director Charlene Briner said Wednesday.
