Air quality levels in parts of the northern United States are being negatively impacted by wildfires that have forced more than 25,000 people to evacuate across Canada as of Tuesday.
There were currently 209 active fires — 106 of which are out of control — throughout Canada as of Tuesday morning, according to the Canadian Interagency Forest Fire Centre.
In some parts of the U.S., air quality has already reached unhealthy levels, particularly in North Dakota, South Dakota, Montana and Minnesota. Separately, there was a fire on the U.S. border along the state lines of Idaho that burned about 250 acres on Sunday, which caused some evacuations, according to the Idaho Department of Lands. The fire was 100% contained and controlled as of Monday evening.
“We should expect at least a couple more rounds of Canadian smoke to come through the U.S. over the next week,” Bryan Jackson, a meteorologist with the National Weather Service, told the Associated Press on Sunday.
Here’s what we know about how the Canadian wildfires will affect the states this week.
Which U.S. states are being impacted by the Canadian wildfires?
The entire state of Minnesota is under an air quality alert until Wednesday, the Minnesota Pollution Control Agency (MPCA) reported on Monday. The northwest part of Minnesota is expected to experience the maroon air quality (AQI) index category, which is the highest level and considered hazardous for everyone.
The Air Quality Index (AQI) is a color-coded numerical scale that helps people understand the health risks and exposures to airborne pollutants at any given time. (You can find your local AQI forecast by entering your ZIP code here.)
“The air will seem hazy or smoky and you won’t be able to see long distances,” the MPCA said about this AQI level. “The air will smell strongly of smoke.”
The MPCA recommends that anyone in northwest and central Minnesota stay indoors while the air quality alert is in effect.
Other areas experiencing unhealthy air quality levels as of Tuesday morning, according to the Environmental Protection Agency’s AirNow tracker, include:
Southeastern South Dakota
Areas experiencing moderate air quality levels as of Tuesday morning, according to the EPA, are:
Other parts of South Dakota
What’s the forecast for the days ahead?
Strong upper-level winds will continue pushing wildfire smoke into the U.S. throughout the week, Weather.com reported on Tuesday. Other states, including Michigan, Ohio, Pennsylvania and West Virginia, may see smoke from the fires, although the thickness will vary compared to states like Minnesota and the Dakotas, according to CBS News.
The smoke will continue to move southeast across the U.S., affecting air quality over most of the East Coast by the end of Tuesday, according to the EPA’s air quality forecast.
What happens when you inhale wildfire smoke?
Wildfire smoke is mostly made up of microscopic particulate matter with elements like acids, chemicals, metals, soil and dust from whatever the fire is burning, according to the Environmental Protection Agency.
When inhaled, these elements can go deep inside a person’s lungs and bloodstream, and research has proven that inhaling wildfire smoke is more dangerous to humans than pollution from other sources.
Small particles of the smoke could stay in the air and continue moving throughout the area even weeks after the fires are extinguished.
The Centers for Disease Control and Prevention reports that wildfire smoke can affect people immediately, causing physical reactions like wheezing, asthma attacks and chest pain.
U.S. offers support to help Canada handle wildfires
Over the weekend, the U.S. Department of Agriculture’s Forest Service deployed an air tanker up north and said it would be sending 150 firefighters and more equipment to help Canada fight the wildfires that have already killed at least two people and forced tens of thousands to evacuate as of Tuesday.
“We are here to help our neighbors during their time of need, and our Forest Service Wildland Firefighters are the best in the business,” Secretary of Agriculture Brooke Rollins said in a press release Saturday. “I am thankful for the men and women who are bravely stepping up to serve. We pray for their success as they fight fires and save lives.”
Canada had its worst wildfire season on record in June 2023, when more than 45 million acres burned. The previous record was set in 1995, when 17.5 million acres burned. Tens of thousands of Canadians were displaced for months in 2023 as historically poor air quality drifted south into the U.S., where the smoke from the Canadian wildfires engulfed the East Coast in an orange, low-visibility haze.
