SmogRank / Episodes / United States
North-eastern United States and Canada, July 2024
For 2 days, from 4 to 5 July 2024, 20 cities in the United States and Canada had PM2.5 at least twice their usual for the time of year. The worst reading was Redford, Michigan, United States: 109.0 µg/m³ on 5 July, about 10× its usual 10.5.
Likely Independence Day fireworks It came on 4 and 5 July, when fireworks smoke fills the air over many US cities at once.
Cities reached 20 in 2 countries
Days 2 4 to 5 July 2024
Worst day 5 July 16 cities counted
Furthest above usual 11× Eastpointe
Day by day
Play 5 July 16 cities at twice their usual or more
Fort Wayne Elkhart Kokomo Muncie Anderson Lima Michigan City Fishers Holland Jenison Lansing Grand Rapids Lafayette Ypsilanti Dayton East Chicago Calumet City Middletown Springfield Columbus Chicago Lebanon Mason White Oak Oak Lawn Norwood Cincinnati Brookfield Bloomington Fort Thomas Des Plaines Dublin Zion Joliet Bay City Naperville Westerville Columbus Gahanna South Milwaukee Cary Milwaukee Champaign Waukesha Port Huron Chatham Sarnia Medina Bloomington Cleveland Rockford Cleveland Heights Decatur Shaker Heights Akron Canton Painesville Peoria Madison St. Thomas London Springfield Warren Youngstown Clinton Wheeling Steubenville Weirton Hermitage Weirton Heights Moline Davenport Kitchener Erie Brantford Pittsburgh Guelph Oregon Perrysburg Wyoming Indianapolis Hammond Windsor Gary South Bend Franklin Park Portage Detroit Kalamazoo Taylor Toledo Lincoln Park Northbrook Dearborn Flint Redford Eastpointe 1 Jul 2 3 4 5 6 7 8 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
Franklin Park Franklin Park, 1 July: 3.5 µg/m³ Franklin Park, 2 July: 5.0 µg/m³ Franklin Park, 3 July: 4.5 µg/m³ Franklin Park, 4 July: 30.4 µg/m³, 2.7× its usual 11.4 Franklin Park, 5 July: 15.1 µg/m³ Franklin Park, 6 July: 7.9 µg/m³ Franklin Park, 7 July: 12.7 µg/m³ Franklin Park, 8 July: 9.6 µg/m³ Dearborn Dearborn, 1 July: 4.6 µg/m³ Dearborn, 2 July: 4.8 µg/m³ Dearborn, 3 July: 8.5 µg/m³ Dearborn, 4 July: 28.9 µg/m³, 2.7× its usual 10.7 Dearborn, 5 July: 39.7 µg/m³, 3.7× its usual 10.7 Dearborn, 6 July: 5.8 µg/m³ Dearborn, 7 July: 7.9 µg/m³ Dearborn, 8 July: 10.5 µg/m³ Portage Portage, 1 July: 6.4 µg/m³ Portage, 2 July: 5.3 µg/m³ Portage, 3 July: 7.6 µg/m³ Portage, 4 July: 27.3 µg/m³, 2.8× its usual 9.9 Portage, 5 July: 15.7 µg/m³ Portage, 6 July: 8.7 µg/m³ Portage, 7 July: 12.7 µg/m³ Portage, 8 July: 9.8 µg/m³ Hammond Hammond, 1 July: 5.7 µg/m³ Hammond, 2 July: 4.1 µg/m³ Hammond, 3 July: 5.6 µg/m³ Hammond, 4 July: 26.1 µg/m³, 2.5× its usual 10.4 Hammond, 5 July: 10.7 µg/m³ Hammond, 6 July: 10.4 µg/m³ Hammond, 7 July: 12.3 µg/m³ Hammond, 8 July: 10.0 µg/m³ Eastpointe Eastpointe, 1 July: no reading Eastpointe, 2 July: no reading Eastpointe, 3 July: no reading Eastpointe, 4 July: 25.8 µg/m³, 3.6× its usual 7.1 Eastpointe, 5 July: 78.3 µg/m³, 11× its usual 7.1 Eastpointe, 6 July: 5.1 µg/m³ Eastpointe, 7 July: 6.6 µg/m³ Eastpointe, 8 July: 7.5 µg/m³ Gary Gary, 1 July: 5.8 µg/m³ Gary, 2 July: 6.9 µg/m³ Gary, 3 July: 9.2 µg/m³ Gary, 4 July: 25.8 µg/m³, 2.6× its usual 9.8 Gary, 5 July: 21.7 µg/m³ Gary, 6 July: 9.9 µg/m³ Gary, 7 July: 12.3 µg/m³ Gary, 8 July: 11.6 µg/m³ Lincoln Park Lincoln Park, 1 July: no reading Lincoln Park, 2 July: no reading Lincoln Park, 3 July: no reading Lincoln Park, 4 July: 25.5 µg/m³, 2.7× its usual 9.5 Lincoln Park, 5 July: 28.8 µg/m³, 3.0× its usual 9.5 Lincoln Park, 6 July: 2.7 µg/m³ Lincoln Park, 7 July: 8.2 µg/m³ Lincoln Park, 8 July: 8.2 µg/m³ Redford Redford, 1 July: 5.4 µg/m³ Redford, 2 July: 8.4 µg/m³ Redford, 3 July: 9.9 µg/m³ Redford, 4 July: 13.0 µg/m³ Redford, 5 July: 109.0 µg/m³, 10× its usual 10.5 Redford, 6 July: 7.6 µg/m³ Redford, 7 July: no reading Redford, 8 July: no reading Flint Flint, 1 July: 6.3 µg/m³ Flint, 2 July: 7.3 µg/m³ Flint, 3 July: 7.1 µg/m³ Flint, 4 July: 7.5 µg/m³ Flint, 5 July: 45.4 µg/m³, 5.7× its usual 7.9 Flint, 6 July: 7.8 µg/m³ Flint, 7 July: 8.8 µg/m³ Flint, 8 July: 9.4 µg/m³ Kalamazoo Kalamazoo, 1 July: 3.3 µg/m³ Kalamazoo, 2 July: 4.9 µg/m³ Kalamazoo, 3 July: 6.0 µg/m³ Kalamazoo, 4 July: 19.3 µg/m³ Kalamazoo, 5 July: 30.8 µg/m³, 2.8× its usual 10.9 Kalamazoo, 6 July: 8.6 µg/m³ Kalamazoo, 7 July: 14.5 µg/m³ Kalamazoo, 8 July: 12.5 µg/m³ Northbrook Northbrook, 1 July: 2.4 µg/m³ Northbrook, 2 July: 4.8 µg/m³ Northbrook, 3 July: 4.3 µg/m³ Northbrook, 4 July: 16.9 µg/m³ Northbrook, 5 July: 29.0 µg/m³, 3.2× its usual 9.2 Northbrook, 6 July: 7.9 µg/m³ Northbrook, 7 July: 11.2 µg/m³ Northbrook, 8 July: 10.2 µg/m³ Toledo Toledo, 1 July: no reading Toledo, 2 July: no reading Toledo, 3 July: 9.4 µg/m³ Toledo, 4 July: 13.1 µg/m³ Toledo, 5 July: 28.7 µg/m³, 2.9× its usual 9.8 Toledo, 6 July: 6.3 µg/m³ Toledo, 7 July: 11.0 µg/m³ Toledo, 8 July: 12.6 µg/m³ Detroit Detroit, 1 July: 3.8 µg/m³ Detroit, 2 July: 5.0 µg/m³ Detroit, 3 July: 7.6 µg/m³ Detroit, 4 July: 16.0 µg/m³ Detroit, 5 July: 28.7 µg/m³, 2.8× its usual 10.4 Detroit, 6 July: 6.0 µg/m³ Detroit, 7 July: 8.2 µg/m³ Detroit, 8 July: 9.9 µg/m³ Wyoming Wyoming, 1 July: 6.1 µg/m³ Wyoming, 2 July: 8.7 µg/m³ Wyoming, 3 July: 8.9 µg/m³ Wyoming, 4 July: 14.2 µg/m³ Wyoming, 5 July: 28.2 µg/m³, 2.3× its usual 12.3 Wyoming, 6 July: 11.4 µg/m³ Wyoming, 7 July: 12.7 µg/m³ Wyoming, 8 July: 12.4 µg/m³ Indianapolis Indianapolis, 1 July: 3.9 µg/m³ Indianapolis, 2 July: 6.5 µg/m³ Indianapolis, 3 July: 8.6 µg/m³ Indianapolis, 4 July: 16.3 µg/m³ Indianapolis, 5 July: 27.1 µg/m³, 2.4× its usual 11.1 Indianapolis, 6 July: 6.7 µg/m³ Indianapolis, 7 July: 21.7 µg/m³ Indianapolis, 8 July: 13.0 µg/m³ Windsor Windsor, 1 July: 4.2 µg/m³ Windsor, 2 July: 4.8 µg/m³ Windsor, 3 July: 7.5 µg/m³ Windsor, 4 July: 9.3 µg/m³ Windsor, 5 July: 26.2 µg/m³, 2.5× its usual 10.3 Windsor, 6 July: 6.2 µg/m³ Windsor, 7 July: 9.2 µg/m³ Windsor, 8 July: 9.1 µg/m³ Taylor Taylor, 1 July: 3.5 µg/m³ Taylor, 2 July: 3.9 µg/m³ Taylor, 3 July: 5.6 µg/m³ Taylor, 4 July: 14.7 µg/m³ Taylor, 5 July: 26.1 µg/m³, 2.9× its usual 9.0 Taylor, 6 July: 5.6 µg/m³ Taylor, 7 July: 7.3 µg/m³ Taylor, 8 July: 7.3 µg/m³ South Bend South Bend, 1 July: 3.2 µg/m³ South Bend, 2 July: 3.7 µg/m³ South Bend, 3 July: 8.1 µg/m³ South Bend, 4 July: 18.9 µg/m³ South Bend, 5 July: 26.1 µg/m³, 2.7× its usual 9.7 South Bend, 6 July: 7.3 µg/m³ South Bend, 7 July: 14.5 µg/m³ South Bend, 8 July: 11.9 µg/m³ Perrysburg Perrysburg, 1 July: 3.8 µg/m³ Perrysburg, 2 July: 5.0 µg/m³ Perrysburg, 3 July: 9.0 µg/m³ Perrysburg, 4 July: 11.5 µg/m³ Perrysburg, 5 July: 25.8 µg/m³, 2.3× its usual 11.1 Perrysburg, 6 July: 6.5 µg/m³ Perrysburg, 7 July: 11.2 µg/m³ Perrysburg, 8 July: 11.0 µg/m³ Oregon Oregon, 1 July: 4.4 µg/m³ Oregon, 2 July: 7.5 µg/m³ Oregon, 3 July: 13.9 µg/m³ Oregon, 4 July: 10.2 µg/m³ Oregon, 5 July: 25.1 µg/m³, 2.3× its usual 11.0 Oregon, 6 July: 10.2 µg/m³ Oregon, 7 July: 15.3 µg/m³ Oregon, 8 July: 17.5 µg/m³ 1 Jul 2 3 4 5 6 7 8 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
Eastpointe Michigan, United States 2 5 July 7.1 11× Redford Michigan, United States 1 5 July 10.5 10× Flint Michigan, United States 1 5 July 7.9 5.7× Dearborn Michigan, United States 2 5 July 10.7 3.7× Northbrook Illinois, United States 1 5 July 9.2 3.2× Lincoln Park Michigan, United States 2 5 July 9.5 3.0× Toledo Ohio, United States 1 5 July 9.8 2.9× Taylor Michigan, United States 1 5 July 9.0 2.9× Kalamazoo Michigan, United States 1 5 July 10.9 2.8× Detroit Michigan, United States 1 5 July 10.4 2.8× Portage Indiana, United States 1 4 July 9.9 2.8× Franklin Park Illinois, United States 1 4 July 11.4 2.7× South Bend Indiana, United States 1 5 July 9.7 2.7× Gary Indiana, United States 1 4 July 9.8 2.6× Windsor Ontario, Canada 1 5 July 10.3 2.5× Hammond Indiana, United States 1 4 July 10.4 2.5× Indianapolis Indiana, United States 1 5 July 11.1 2.4× Wyoming Michigan, United States 1 5 July 12.3 2.3× Perrysburg Ohio, United States 1 5 July 11.1 2.3× Oregon Ohio, United States 1 5 July 11.0 2.3×
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 and Canada
Number 53 of 141 episodes in the United States and Canada 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 and Canada, July 2024 20 Bars: cities reached; colour: the level of the episode's highest daily reading. All 141 .
Use this page SmogRank, North-eastern United States and Canada, July 2024: 20 cities with PM2.5 at twice their usual or more, 4 to 5 July 2024, smogrank.com/episodes/2024-07-north-eastern-united-states-and-canada (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.
