A sailboat passes Montrose Point in front of a hazy Willis Tower on July 26, 2023.
Visitors to Navy Pier photograph wildfire haze obscuring the Chicago skyline on June 27, 2023.
A water taxi travels offshore in Lake Michigan while wildfire haze obscures the Chicago skyline Tuesday, June 27, 2023. (Brian Cassella/Chicago Tribune)
A plane takes off from Chicago Midway International Airport as haze from Canadian wildfires continues to hang over the city on June 28, 2023.
The sun, muted from Canadian wildfire smoke, sets behind a water tower on Chicago’s North Side, June 30, 2023.
The sun rises as smoke from Canadian wildfires passes through the area on June 28, 2023 in Chicago.
A bicyclist with a face mask is reflected in a car mirror, as cyclists ride down Milwaukee Avenue during a second straight day of hazy and poor air quality conditions in Chicago, June 28, 2023.
Wildfire smoke clouds the Chicago skyline along Halsted Street near Chicago as poor air quality continues on June 28, 2023.
Bicyclists and walkers use The 606 Trail near Damen Avenue during the second day poor air quality conditions in Chicago, June 28, 2023.
A Southwest Airlines jet takes off from Chicago Midway Airport as haze from Canadian wildfires continues to hang over Chicago on June 28, 2023.
The sun rises as smoke from Canadian wildfires hangs over Chicago on June 28, 2023.
Smoke from Canada wildfires creates a haze in the sky as Chicago Cubs shortstop Dansby Swanson (7) and first baseman Cody Bellinger (24) head out to the field in the ninth inning of a game against the Philadelphia Phillies at Wrigley Field on June 27, 2023.
Lifeguard Geysi Flores wears a mask at 31st Street Beach in Chicago on June 27, 2023. She said she was wearing it because of the poor air quality from the Canadian wildfires.
Riley Boyle, 19, and Andrew Newcomer, right, 19, both of Kokomo, Indiana, wear face masks in an effort to protect themselves from smokey air due to wildfires in Canada during a game between the Chicago Cubs and the Philadelphia Phillies at Wrigley Field on June 27, 2023.
People walk through Lurie Garden, in Chicago’s Millennium Park, as haze from Canadian wildfires hangs over the city on June 27, 2023.
From left, Aly Bothman, Miranda Mireles, Max Loy, and Liam Mireles wear masks at Promontory Point while smoke from Canadian wildfires passes through the area on June 27, 2023. According to the monitoring site IQAir, Chicago had the worst air quality out of 95 cities worldwide Tuesday.
Vehicles move northbound along DuSable Lake Shore Drive as smoke from Canadian wildfires hangs over Chicago on June 27, 2023.
Wildfire haze obscures the Chicago skyline while people ride the Centennial Wheel at Navy Pier, June 27, 2023.
The Chicago skyline is blanketed in haze from Canadian wildfires seen from Solidarity Drive on June 27, 2023, as weather officials issued an air quality alert.
A plane passes over Navy Pier in the hazy sky, June 27, 2023.
Liam Mireles catches a football as Miranda Mireles, center, talks with Aly Bothman as the group wear masks because of the wildfire smoke at Chicago’s Promontory Point, June 27, 2023.
Illinois College football player William Campbell, 23, practices his drills during the air quality alert at 31st Street Beach, June 27, 2023.
A water taxi travels offshore in Lake Michigan while wildfire haze obscures the Chicago skyline, June 27, 2023.
Wildfire haze blankets the Chicago skyline while people visit Navy Pier on June 27, 2023.
Wildfire haze obscures the Chicago skyline while people ride the Centennial Wheel Ferris wheel at Navy Pier, June 27, 2023.
A person wears a mask at Navy Pier while wildfire haze obscures the Chicago skyline June 27, 2023.
A red flag flies at hazy 31st Street Beach on June 27, 2023.
Canadian wildfires haze covers Chicago, seen from Roosevelt Road on June 27, 2023.
Cars on a hazy Austin Boulevard along the Chicago and Oak Park border on June 27, 2023.
Haze blankets Chicago seen from the Museum Campus, June 27, 2023.
A hazy, cloudy partial Chicago skyline is seen from Lake Michigan near Navy Pier, June 15, 2023.
A hazy Chicago skyline looms behind the family of Yarzita Perez as they help her pose for quinceañera photos on June 6, 2023. Recent vibrant sunsets and a hazy skyline in the city can be traced to a combination of factors.
A person walks near North Avenue Beach as clouds and haze obstruct the city skyline onJune 15, 2023, in Chicago.
A hazy partial skyline is visible from the Bucktown neighborhood of Chicago on June 6, 2023. Chicago just had its driest May in decades.
The Chicago skyline, seen from Whiting Lakefront Park in Indiana, is shrouded in haze on June 6, 2023.
A group of youths watch the sunset behind the skyline, as seen from Solidarity Drive, May 17, 2023, in Chicago. Smoke from Canadian wildfires has dimmed the brightness of the sun this week.
A jet departing O’Hare International Airport ascends past a view of the sun on May 16, 2023. Recent vibrant, reddish sunsets and a hazy skyline in Chicago can be traced to a combination of particulate matter and smoke from Canadian wildfires and pollutants that create ground-level ozone.
The sun sets behind the 600 block of Chicago’s South Michigan Avenue, as seen from East Solidarity Drive on May 17, 2023. A combination of factors, including smoke from Canadian wildfires, was creating poorer air quality in Chicago.
The sun sets behind the Chicago skyline, as seen from East Solidarity Drive on May 17, 2023. Smoke from Canadian wildfires dimmed the brightness of the sun.
