As a child growing up in New York City in the 1990s, I remember trudging through nearly a foot of snow to get to public school, which almost never closed. Each time, city crews ensured that the roads and sidewalks were salted in advance. A fleet of snowplows quickly cleared streets so that buses could run. The preparations were not only at the city level; for their part, parents and caregivers bundled up their children in gloves, hats, winter coats and mittens to brave the cold. Community groups held winter coat drives for those who could not afford them.
Thirty years later, my childhood self could not have predicted that U.S. cities in the Northeast and Midwest would be facing a very different variety of recurring extreme weather event: wildfire smoke transported from Canada — a threat that has hit Chicago particularly hard in recent years and won’t be disappearing anytime soon.
Amid the myriad weather predictions worldwide related to 2026-2027 super El Nino conditions, the Canadian government has released a report predicting an uptick in wildfires across multiple regions in spring and summer 2027.
Looking back at the last several summers, it’s hard to identify one where Chicago was not affected by transported wildfire smoke. In June 2023, Chicago’s air quality was at the bottom of the list of cities worldwide.
And while the smoke filled the air across the city, its dangers impacted some communities more than others.
In a newly published study, our team of investigators at the Duke Global Health Institute and the University of Illinois Chicago Center for Extreme Conditions and Health Excellence examined patterns of exposure across the city during the June 2023 wildfire smoke event. While we found that no neighborhood was untouched by elevated levels of particulate matter, neighborhoods with worse baseline air quality, lower socioeconomic status and higher proportions of non-Hispanic Black and Hispanic populations took a longer time to recover in the days after the event, further amplifying existing air quality exposure disparities.
Poor air quality is linked to many adverse health outcomes, including respiratory disease, cardiometabolic disease and cancer. The exposure risks are even larger for vulnerable populations, including older adults, children and those with preexisting conditions such as asthma or diabetes. A 2026 study in Science Advances found that wildfire smoke particles accounted for more than 24,000 annual deaths in the U.S. between 2006 and 2020.
In July, the city of Chicago once again ranked among the worst in air quality in the world, with a composite daily Air Quality Index for fine particulate matter of 400. For a U.S. city to reach an Air Quality Index above 300 — classified as “hazardous” — is historically highly unusual.
Given that wildfire smoke is not going away, this is a public health problem that even regions of the U.S. historically unaffected by wildfires must be prepared for, especially during the summer months when heat plays a role in the equation. Early warning systems are needed to reduce exposure to vulnerable populations. Just as Northeastern and Midwestern municipalities provide alerts and cleared roadways in a snowstorm in the winter months, it should be regular practice to share air quality alerts and provide access to mitigation tools during a wildfire event in the summer.
Such strategies might include, but are not limited to, indoor air sensors, N95 and KN95 masks and portable air cleaners with a HEPA air filter. For older housing without central air conditioning, at-risk individuals should have affordable access to fans and air conditioners so that they do not have to choose between thermal comfort and breathing smoke through an open window.
Looking back on this summer’s transported wildfire smoke events and the pattern over the last several summers, some have suggested that Canada should do more to prevent and address wildfires so that their impact does not reach the U.S. This would not change the reality that extreme weather events are increasing in frequency and severity. Today, firefighters continue to battle against fires in Yosemite, with only 40% contained so far. Regardless of the source of the smoke, we must take responsibility for extreme weather events which affect the health of the most at-risk populations here in the U.S.
As wildfire smoke events become the norm even for areas geographically distant from the source, U.S. cities need to prepare with the same practiced vigilance they apply to snowstorms, and the time to prepare is now — not after the smoke and its attendant damage have arrived.
Melissa Fiffer is a senior research scientist at the University of Illinois Chicago’s Children’s Environmental Health Initiative, adjunct assistant professor at UIC’s School of Public Health and co-director of the UIC Center for Extreme Conditions and Health Excellence Data Core. She is also a University of Illinois Public Voices fellow with The OpEd Project.