Three US cities rank in the top 5 for worst air quality in the world as of Thursday morning. Canadian wildfire smoke will continue to be a problem through at least Saturday across the northern U.S.
America is dominating for the worst air quality in the world as Canadian wildfire smoke moves into the upper tier of the country, causing smoky, hazy skies for millions.
A recent wildfire outbreak across western Ontario, Canada, and Minnesota is sending thick plumes of smoke toward the Great Lakes and Northeast through Thursday.
According to the Canadian Interagency Forest Fire Centre, 69 fires are burning out of control in Ontario, mostly in the western part of the province, north of Minnesota.
(FOX Weather)
As of Thursday morning, three cities in the U.S. ranked in the top five worst air quality in the world because of wildfire smoke, according to IQ Air.
(FOX Weather)
1. Detroit, Michigan
Detroit ranked in first place across the whole world, according to IQ Air.
As of 10 a.m. central on Thursday, Detroit reportedly had an air quality of 724, more than double the qualifying ranking for hazardous air.
THESE MAJOR US CITIES ARE EXPECTED TO SEE THE WORST OF THE CANADIAN WILDFIRE SMOKE
Hazardous air quality ranks 301 or higher, and has the potential to cause a health emergency and impact everyone, not just those sensitive.
Air quality at Isle Royale National Park in Michigan on Thursday morning.
(FOX Weather)
The Michigan Department of Environment, Great Lakes and Energy extended an air quality alert for the entire state into Friday, warning of air quality ranging from very unhealthy to hazardous.
2. Minneapolis, Minnesota
Minneapolis took second place on the list.
An air quality index of 289 was reported by IQ Air, as of 11 a.m. central time.
WATCH: DRAMATIC VIDEO SHOWS FREIGHT TRAIN, CREW CAUGHT IN CANADIAN WILDFIRES
“Very unhealthy” air quality is anything from 201 to 300, the second-highest reported index.
MINNEAPOLIS, MINNESOTA – JULY 15: A general view of downtown as dense smoke effects visibility on July 15, 2026 in Minneapolis, Minnesota.
(Stephen Maturen / Getty Images)
When a very unhealthy air quality is reported, outdoor activities should be limited.
The Minnesota Pollution Control Agency issued an air quality alert through 11 a.m. CT on Friday, warning that air quality is likely to reach hazardous levels.
3. Chicago, Illinois
Chicago ranks third place, also with a very unhealthy air quality of 250, according to IQ Air.
US LIKELY FACES INCREASING WILDFIRE RISKS AS AMERICANS BUILD IN FIRE-PRONE AREAS, STUDY FINDS
The Illinois Environmental Protection Agency issued a Red Forecast Air Pollution Action Day for Thursday, warning people to limit time outside.
CHICAGO, ILLINOIS – JULY 16: An aerial shows smoke from Canadian wildfires blanketing the city on July 16, 2026 in Chicago, Illinois.
(Scott Olson / Getty Images)
Air quality could reach a hazardous level as the day goes on. Toronto, Canada, ranked fourth place.
Conditions are likely to improve on Friday for many in the U.S., as the smoke pushes south and east.
Wildfire smoke is expected to linger across much of the region through Saturday before another cold front clears the smoke from the eastern U.S.
