Photos: Smoky haze hovers over American cities
Smoke from Canadian wildfires has lowered curtains of haze on broad swaths of Canada and the United States, pushing into southern Illinois, Indiana and Ohio, and moving into parts of West Virginia.

Haze obscures the Chicago skyline Tuesday, June 27, 2023. It's not fog that's blanketing the skies across the Chicago area Tuesday - it's haze from Canadian wildfires, which, along with higher ozone levels is continuing to create low visibility conditions and lead to Air Quality Alerts throughout the area. (AP Photo/Teresa Crawford)

A haze is seen from Canadian wildfires Tuesday, June 27, 2023, in Whitefish Bay, Wis. The haze from Canadian wildfires, which, along with higher ozone levels is continuing to create low visibility conditions and lead to air quality alerts throughout the area. (AP Photo/Morry Gash)

A person walks along the shore of Lake Michigan as the downtown skyline is blanketed in haze from Canadian wildfires Tuesday, June 27, 2023, in Chicago. (AP Photo/Kiichiro Sato)

A person rides a bicycle along the shore of Lake Michigan as the downtown skyline is blanketed in haze from Canadian wildfires Tuesday, June 27, 2023, in Chicago. (AP Photo/Kiichiro Sato)

A person walks along the shore of Lake Michigan as the downtown skyline is blanketed in haze from Canadian wildfires Tuesday, June 27, 2023, in Chicago. (AP Photo/Kiichiro Sato)

A haze is seen over the Milwaukee Art Museum Tuesday, June 27, 2023, in Milwaukee. The haze from Canadian wildfires, which, along with higher ozone levels is continuing to create low visibility conditions and lead to Air Quality Alerts throughout the area. (AP Photo/Morry Gash)

The Marriott Marquis, left, and the Hyatt Regency McCormick Place, center, stand above The McCormick Place Convention Center in a veil of haze from Canadian wildfires obscuring the majestic Chicago skyline, as seen from the city's Bronzeville neighborhood Tuesday, June 27, 2023, in Chicago. (AP Photo/Charles Rex Arbogast)

Smoke from wildfires in Canada blankets Grand Rapids, Mich., on Tuesday, June 27, 2023. The smoke is reducing visibility and air quality. (Neil Blake/MLive.com/The Grand Rapids Press via AP)

The flags of Chicago Cubs' Hall of Fame players Ernie Banks (14) Ron Santo (10) and Ferguson Jenkins fly off the Wrigley Field left field foul pole as a veil of haze from Canadian wildfires shroud high rise buildings along Lake Michigan before a baseball game between the Cubs and the Philadelphia Phillies Tuesday, June 27, 2023, in Chicago. (AP Photo/Charles Rex Arbogast)

The sun sets, seen through drifting smoke from the Canadian wildfires, before a baseball game between the Chicago Cubs and the Philadelphia Phillies at Wrigley Field on Tuesday, June 27, 2023, in Chicago. (AP Photo/Charles Rex Arbogast)

A setting sun, tinged orange by airborne ash from wildfires in Canada, draws the interest of cyclists in Oconomowoc, Wis., Tuesday, June 27, 2023. (John Hart/Wisconsin State Journal via AP)

A haze is seen as the sun sets over the Holy Hill Basilica and National Shrine of Mary Tuesday, June 27, 2023, in Hubertus, Wis. The haze from Canadian wildfires, along with higher ozone levels, is continuing to create low visibility conditions and lead to Air Quality Alerts throughout the area. (AP Photo/Morry Gash)

Haze from Canadian wildfires blankets the downtown Pittsburgh skyline as seen from Elliott, Pa., Wednesday, June 28, 2023. (Benjamin B. Braun/Pittsburgh Post-Gazette via AP)

Haze from Canadian wildfires blankets the downtown Pittsburgh skyline as seen from West End Overlook in Elliott, Pa., Wednesday, June 28, 2023. (Benjamin B. Braun/Pittsburgh Post-Gazette via AP)

Haze from Canadian wildfires blankets the downtown Pittsburgh skyline as seen from West End Overlook in Elliott, Pa., Wednesday, June 28, 2023. (Benjamin B. Braun/Pittsburgh Post-Gazette via AP)

A person sits near the Ohio River as smoke from wildfires is visible over downtown Cincinnati, Wednesday, June 28, 2023. (AP Photo/Joshua A. Bickel)

The Minneapolis skyline, as viewed from the Mississippi River, is enveloped in wildfire smoke during an air quality alert on Wednesday, June 28, 2023, in Minneapolis. (Kerem Yücel/Minnesota Public Radio via AP)

Freighters pass along the Detroit River with Windsor, Ontario in the background as smoke fills the sky reducing visibility Wednesday, June 28, 2023, as seen from Detroit. The Detroit area has some of the worst air quality in the United States as smoke from Canada's wildfires spreads southward. (AP Photo/Paul Sancya)

Smoke from the Canadian wildfires obscures the St. Louis skyline as Keith Major runs sprints on the track at St. Louis University, Wednesday, June 28, 2023. Major, a police officer in the city of St. Louis, is training for the World Police and Fire Games that is being held in Winnipeg, He said he was concerned about the air quality and compared training in the smoky air to training at high altitudes. (David Carson/St. Louis Post-Dispatch via AP)

FILE - A man tosses a fishing net into the Ohio River as smoke from wildfires is visible over downtown Cincinnati, June 28, 2023. Forecasters say there won’t be large breaks for much of America anytime soon from eye-watering dangerous smoke from fire-struck Canada. (AP Photo/Joshua A. Bickel, File)

Haze obscures buildings in the Rogers Park neighborhood of Chicago Wednesday, June 28, 2023. It's not fog that's blanketing the skies across the Chicago area this week — it's haze from Canadian wildfires, which, along with higher ozone levels is continuing to create low visibility conditions and lead to Air Quality Alerts throughout the area. (AP Photo/Erin Hooley)

Haze can be seen along the shoreline of Lake Michigan Wednesday, June 28, 2023 in Chicago. It's not fog that's blanketing the skies across the Chicago area this week — it's haze from Canadian wildfires, which, along with higher ozone levels is continuing to create low visibility conditions and lead to Air Quality Alerts throughout the area. (AP Photo/Erin Hooley)