SmogRank / Episodes / United States
North-eastern United States, July 2026
For 1 day, on 1 July 2026, 24 cities in the United States had PM2.5 at least twice their usual for the time of year. The worst reading was Westerville, Ohio, United States: 31.8 µg/m³ on 1 July, about 3.1× its usual 10.3.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 24 in 1 country
Days 1 1 July 2026
Worst day 1 July 24 cities counted
Furthest above usual 3.6× Mason
Day by day
Play 1 July 24 cities at twice their usual or more
Fort Wayne Muncie Anderson Toledo Kokomo Elkhart Fishers Ann Arbor White Oak Kalamazoo Ypsilanti Dublin South Bend Fort Thomas Indianapolis Taylor Gahanna Lincoln Park Dearborn Columbus Southfield Detroit Windsor Royal Oak Lafayette Eastpointe Flint Michigan City Holland Bloomington Portage Gary Chatham East Chicago Hammond Calumet City Port Huron Dolton Sarnia Terre Haute Akron Ashland Blue Island Chicago Shaker Heights Evergreen Park Oak Lawn Evanston Bridgeview Skokie Elmwood Park Brookfield Niles Jasper Franklin Park Park Ridge Des Plaines Painesville Joliet Zion Naperville Champaign Aurora South Milwaukee Elgin Cary Warren St. Thomas Youngstown London Steubenville Weirton Brookfield Weirton Heights Waukesha Hermitage Bloomington Decatur Oconomowoc Upper Saint Clair Rockford Pittsburgh Erie Wilkinsburg West Mifflin McKeesport Brantford Peoria Springfield Madison Middleton Hamilton Waterdown Redford Grand Rapids Cleveland Wyoming Canton Columbus Oregon Portsmouth Norwood Middletown Jenison Lansing Milwaukee Northbrook Springfield Perrysburg Cincinnati Dayton Lebanon Westerville Medina Lima Cleveland Heights Mason 28 Jun 29 30 1 Jul 2 3 4 Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.
How it spread
Westerville Westerville, 28 June: 6.3 µg/m³ Westerville, 29 June: 10.9 µg/m³ Westerville, 30 June: 20.2 µg/m³ Westerville, 1 July: 31.8 µg/m³, 3.1× its usual 10.3 Westerville, 2 July: 25.1 µg/m³ Westerville, 3 July: 19.2 µg/m³ Westerville, 4 July: 17.0 µg/m³ Lima Lima, 28 June: 12.4 µg/m³ Lima, 29 June: 15.2 µg/m³ Lima, 30 June: 23.5 µg/m³ Lima, 1 July: 30.9 µg/m³, 3.2× its usual 9.7 Lima, 2 July: 20.6 µg/m³ Lima, 3 July: 17.0 µg/m³ Lima, 4 July: 13.4 µg/m³ Mason Mason, 28 June: 3.6 µg/m³ Mason, 29 June: 13.5 µg/m³ Mason, 30 June: 18.6 µg/m³ Mason, 1 July: 30.5 µg/m³, 3.6× its usual 8.4 Mason, 2 July: 21.0 µg/m³ Mason, 3 July: 16.0 µg/m³ Mason, 4 July: 8.7 µg/m³ Middletown Middletown, 28 June: 7.6 µg/m³ Middletown, 29 June: 17.0 µg/m³ Middletown, 30 June: 22.9 µg/m³ Middletown, 1 July: 30.4 µg/m³, 2.7× its usual 11.3 Middletown, 2 July: 23.4 µg/m³ Middletown, 3 July: 21.9 µg/m³ Middletown, 4 July: 21.0 µg/m³ Cincinnati Cincinnati, 28 June: 6.8 µg/m³ Cincinnati, 29 June: 15.0 µg/m³ Cincinnati, 30 June: 20.9 µg/m³ Cincinnati, 1 July: 30.3 µg/m³, 2.9× its usual 10.6 Cincinnati, 2 July: 20.9 µg/m³ Cincinnati, 3 July: 16.9 µg/m³ Cincinnati, 4 July: 14.2 µg/m³ Wyoming Wyoming, 28 June: 11.4 µg/m³ Wyoming, 29 June: 13.7 µg/m³ Wyoming, 30 June: 21.7 µg/m³ Wyoming, 1 July: 30.3 µg/m³, 2.5× its usual 12.0 Wyoming, 2 July: 15.6 µg/m³ Wyoming, 3 July: 12.3 µg/m³ Wyoming, 4 July: no reading Norwood Norwood, 28 June: 7.0 µg/m³ Norwood, 29 June: 16.6 µg/m³ Norwood, 30 June: 21.7 µg/m³ Norwood, 1 July: 29.5 µg/m³, 2.7× its usual 11.0 Norwood, 2 July: 22.4 µg/m³ Norwood, 3 July: 19.9 µg/m³ Norwood, 4 July: 13.7 µg/m³ Dayton Dayton, 28 June: 4.8 µg/m³ Dayton, 29 June: 13.9 µg/m³ Dayton, 30 June: 20.6 µg/m³ Dayton, 1 July: 29.3 µg/m³, 3.0× its usual 9.8 Dayton, 2 July: 20.5 µg/m³ Dayton, 3 July: 14.7 µg/m³ Dayton, 4 July: 16.0 µg/m³ Perrysburg Perrysburg, 28 June: 10.4 µg/m³ Perrysburg, 29 June: 11.5 µg/m³ Perrysburg, 30 June: 21.3 µg/m³ Perrysburg, 1 July: 28.6 µg/m³, 2.9× its usual 9.9 Perrysburg, 2 July: 20.8 µg/m³ Perrysburg, 3 July: 14.2 µg/m³ Perrysburg, 4 July: 12.7 µg/m³ Springfield Springfield, 28 June: 5.7 µg/m³ Springfield, 29 June: 13.0 µg/m³ Springfield, 30 June: 18.6 µg/m³ Springfield, 1 July: 28.0 µg/m³, 2.9× its usual 9.8 Springfield, 2 July: 20.2 µg/m³ Springfield, 3 July: 15.1 µg/m³ Springfield, 4 July: 20.0 µg/m³ Oregon Oregon, 28 June: 7.1 µg/m³ Oregon, 29 June: 9.4 µg/m³ Oregon, 30 June: 21.1 µg/m³ Oregon, 1 July: 27.6 µg/m³, 2.6× its usual 10.6 Oregon, 2 July: 21.6 µg/m³ Oregon, 3 July: 14.6 µg/m³ Oregon, 4 July: 9.6 µg/m³ Medina Medina, 28 June: 9.6 µg/m³ Medina, 29 June: 7.7 µg/m³ Medina, 30 June: 14.5 µg/m³ Medina, 1 July: 26.9 µg/m³, 3.2× its usual 8.3 Medina, 2 July: 19.3 µg/m³ Medina, 3 July: 12.1 µg/m³ Medina, 4 July: 9.3 µg/m³ Cleveland Cleveland, 28 June: 9.3 µg/m³ Cleveland, 29 June: 11.3 µg/m³ Cleveland, 30 June: 15.9 µg/m³ Cleveland, 1 July: 26.7 µg/m³, 2.5× its usual 10.6 Cleveland, 2 July: 19.5 µg/m³ Cleveland, 3 July: 13.1 µg/m³ Cleveland, 4 July: 13.4 µg/m³ Northbrook Northbrook, 28 June: 9.3 µg/m³ Northbrook, 29 June: 13.5 µg/m³ Northbrook, 30 June: 24.5 µg/m³ Northbrook, 1 July: 26.4 µg/m³, 2.9× its usual 9.0 Northbrook, 2 July: 11.6 µg/m³ Northbrook, 3 July: 7.9 µg/m³ Northbrook, 4 July: 9.0 µg/m³ Columbus Columbus, 28 June: 4.5 µg/m³ Columbus, 29 June: 8.6 µg/m³ Columbus, 30 June: 14.9 µg/m³ Columbus, 1 July: 26.4 µg/m³, 2.6× its usual 10.1 Columbus, 2 July: 22.0 µg/m³ Columbus, 3 July: 15.5 µg/m³ Columbus, 4 July: 12.9 µg/m³ Canton Canton, 28 June: 9.5 µg/m³ Canton, 29 June: 8.2 µg/m³ Canton, 30 June: 15.7 µg/m³ Canton, 1 July: 26.4 µg/m³, 2.6× its usual 10.3 Canton, 2 July: 22.3 µg/m³ Canton, 3 July: 14.5 µg/m³ Canton, 4 July: 12.1 µg/m³ Redford Redford, 28 June: 6.6 µg/m³ Redford, 29 June: 8.0 µg/m³ Redford, 30 June: 15.1 µg/m³ Redford, 1 July: 25.9 µg/m³, 2.4× its usual 10.9 Redford, 2 July: 13.8 µg/m³ Redford, 3 July: 5.7 µg/m³ Redford, 4 July: 26.4 µg/m³ Cleveland Heights Cleveland Heights, 28 June: 7.6 µg/m³ Cleveland Heights, 29 June: 8.8 µg/m³ Cleveland Heights, 30 June: 14.5 µg/m³ Cleveland Heights, 1 July: 25.5 µg/m³, 3.4× its usual 7.5 Cleveland Heights, 2 July: 17.9 µg/m³ Cleveland Heights, 3 July: 13.6 µg/m³ Cleveland Heights, 4 July: 19.1 µg/m³ Lebanon Lebanon, 28 June: 2.9 µg/m³ Lebanon, 29 June: 11.1 µg/m³ Lebanon, 30 June: 16.8 µg/m³ Lebanon, 1 July: 25.5 µg/m³, 3.1× its usual 8.1 Lebanon, 2 July: 17.8 µg/m³ Lebanon, 3 July: 15.7 µg/m³ Lebanon, 4 July: 14.4 µg/m³ Milwaukee Milwaukee, 28 June: 9.2 µg/m³ Milwaukee, 29 June: 10.4 µg/m³ Milwaukee, 30 June: 19.1 µg/m³ Milwaukee, 1 July: 25.3 µg/m³, 2.9× its usual 8.8 Milwaukee, 2 July: 6.6 µg/m³ Milwaukee, 3 July: 6.9 µg/m³ Milwaukee, 4 July: 11.7 µg/m³ Lansing Lansing, 28 June: 8.3 µg/m³ Lansing, 29 June: 8.8 µg/m³ Lansing, 30 June: 16.8 µg/m³ Lansing, 1 July: 25.2 µg/m³, 2.8× its usual 8.9 Lansing, 2 July: 14.0 µg/m³ Lansing, 3 July: 7.2 µg/m³ Lansing, 4 July: 9.1 µg/m³ Portsmouth Portsmouth, 28 June: 6.9 µg/m³ Portsmouth, 29 June: 10.5 µg/m³ Portsmouth, 30 June: 16.9 µg/m³ Portsmouth, 1 July: 25.2 µg/m³, 2.7× its usual 9.2 Portsmouth, 2 July: 23.9 µg/m³ Portsmouth, 3 July: 20.6 µg/m³ Portsmouth, 4 July: 16.8 µg/m³ Grand Rapids Grand Rapids, 28 June: 7.2 µg/m³ Grand Rapids, 29 June: 9.7 µg/m³ Grand Rapids, 30 June: 18.4 µg/m³ Grand Rapids, 1 July: 25.1 µg/m³, 2.5× its usual 9.9 Grand Rapids, 2 July: 10.1 µg/m³ Grand Rapids, 3 July: 7.3 µg/m³ Grand Rapids, 4 July: 12.0 µg/m³ Jenison Jenison, 28 June: 6.8 µg/m³ Jenison, 29 June: 9.8 µg/m³ Jenison, 30 June: 18.3 µg/m³ Jenison, 1 July: 25.0 µg/m³, 2.8× its usual 8.8 Jenison, 2 July: 10.4 µg/m³ Jenison, 3 July: 6.9 µg/m³ Jenison, 4 July: 12.7 µg/m³ 28 Jun 29 30 1 Jul 2 3 4 Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more. Good 0–50
Moderate 51–100
Sensitive groups 101–150
Unhealthy 151–200
Very unhealthy 201–300
Hazardous 301+
Every city it reached
City Days Highest Usual Above usual
Mason Ohio, United States 1 1 July 8.4 3.6× Cleveland Heights Ohio, United States 1 1 July 7.5 3.4× Lima Ohio, United States 1 1 July 9.7 3.2× Medina Ohio, United States 1 1 July 8.3 3.2× Westerville Ohio, United States 1 1 July 10.3 3.1× Lebanon Ohio, United States 1 1 July 8.1 3.1× Dayton Ohio, United States 1 1 July 9.8 3.0× Cincinnati Ohio, United States 1 1 July 10.6 2.9× Perrysburg Ohio, United States 1 1 July 9.9 2.9× Springfield Ohio, United States 1 1 July 9.8 2.9× Northbrook Illinois, United States 1 1 July 9.0 2.9× Milwaukee Wisconsin, United States 1 1 July 8.8 2.9× Lansing Michigan, United States 1 1 July 8.9 2.8× Jenison Michigan, United States 1 1 July 8.8 2.8× Middletown Ohio, United States 1 1 July 11.3 2.7× Norwood Ohio, United States 1 1 July 11.0 2.7× Portsmouth Ohio, United States 1 1 July 9.2 2.7× Oregon Ohio, United States 1 1 July 10.6 2.6× Columbus Ohio, United States 1 1 July 10.1 2.6× Canton Ohio, United States 1 1 July 10.3 2.6× Wyoming Michigan, United States 1 1 July 12.0 2.5× Cleveland Ohio, United States 1 1 July 10.6 2.5× Grand Rapids Michigan, United States 1 1 July 9.9 2.5× Redford Michigan, United States 1 1 July 10.9 2.4×
Daily means in µg/m³, over the days each city counted in this episode. Highest: its highest of those days. Usual: the city's median for the time of year of that day (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that, with a usual under 5 µg/m³ taken as 5.
Against other episodes in the United States
Number 42 of 130 episodes in the United States since our records began, by cities reached.
Eastern United States and Canada, 25 June to 2 July 2023 280 North-eastern United States and Canada, July 2026 264 Eastern United States and Canada, May and June 2023 261 North-eastern United States and Canada, 30 July to 9 August 2025 241 Eastern United States and Canada, July 2023 240 North-eastern United States and Canada, 3 to 9 June 2025 196 Eastern United States and Canada, 14 to 19 June 2023 161 North-eastern United States and Canada, 12 to 16 July 2025 119 North-western United States and Canada, August 2023 110 North-eastern United States and Canada, 10 to 14 June 2025 104 North-western United States and Canada, 4 to 11 August 2026 99 North-eastern United States and Canada, 14 to 19 February 2026 96 North-eastern United States, July 2026 24 Bars: cities reached; colour: the level of the episode's highest daily reading. All 130 .
Use this page SmogRank, North-eastern United States, July 2026: 24 cities with PM2.5 at twice their usual or more, 1 July 2026, smogrank.com/episodes/2026-07-north-eastern-united-states (accessed 4 October 2026).
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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms .
An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes . Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.
