Choking smoke billowing from deadly wildfires in Canada is heading toward the U.S. this weekend.
Forecasters in multiple states warned residents to expect degraded air quality and reduced visibility.
“Smoke from wildfires in Canada is expected to overspread portions of central Illinois during today. This may result in reduced visibility at times and contribute to health concerns for people that are unusually sensitive to air pollution,” the National Weather Service in Lincoln said in a post on social media.
Just under three hours away, the city of Chicago — which was recently hit with a historic dust storm — is also expected to see impacts, as well as more storms.
Wisconsin, Michigan, Kentucky, Minnesota, Wyoming, and Iowa offices also told residents to prepare for hazy skies and the smell of smoke.
"Most of the time, the smoke will be high-flying and dim the sun, leading to vivid sunrises and sunsets and causing a hazy appearance to the sky overhead," AccuWeather Meteorologist Brandon Buckingham said in a statement.
The advisories come just under two years since smoke from Canada’s worst fire season on record turned New York City an eerie burnt orange.
This year, the smoke is being guided by steering winds that are blowing it to the southeast.
Wildfires produce a mix of pollutants and particle pollution, which is also referred to as particulate matter. PM 2.5, which is considered to be a carcinogen, is the air pollutant of greatest concern to public health from wildfire smoke. It can travel deep into the lungs and enter the bloodstream.
The health effects of this pollution can range from eye and throat irritation to heart failure and premature death. It may impact the body’s ability to remove viruses or bacteria from the lungs. Even short-term exposures are linked to an increased risk of exacerbation of pre-existing respiratory and cardiovascular disease.
Furthermore, recent research has found that PM.25 can have health effects for up to three months after exposure.
“Even brief exposures from smaller fires that last only a few days can lead to long-lasting health effects,” said Dr. Yaguang Wei, an assistant professor of environmental medicine at Mount Sinai’s Icahn School of Medicine.
The recent threat comes as massive blazes burning across Canada have killed two people and forced the evacuations of thousands. On Thursday, the province of Manitoba declared a state of emergency. There are 175 active wildfires and 12 that cropped up on Friday. Since the year’s start, more than 700,000 acres have gone up in flames. The pre-summer fires come following the second-worst fire season of the century.
The 2025 fires have also been fueled by climate change-driven heat. In Manitoba, temperatures have exceeded the average by as much as 22 to 24.3 degrees, according to nonprofit Climate Central.
As heat builds in from the western U.S. next week, AccuWeather said that the hot air and any lingering smoke may also lead to ozone issues over a broad area of the north-central region.
"Most of these areas in the Midwest will have days where there is little or no rain around and the sun is out over the weekend. So the smoke will be more noticeable," AccuWeather Senior Meteorologist Adam Douty said. "The smoke may reach into the Northeast as well, but with extensive clouds and showers this weekend, the smoky haze may be mixed in and not so obvious."
