Worst air pollution Hamilton, today and tomorrow
Today (16 July): Air quality in Hamilton is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 11:00 AM (O3: 33.2/100).
Tomorrow (17 July 2026): Air quality in Hamilton is fair. All pollutants stay as today. Pollution peaks around 8:00 AM (O3: 27.6/100). Airmine updates local air quality forecasts four times daily.
For long term forecasts and maps, see the Airmine app
Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
Use our Strava plugin to check your own exposure.
Hamilton's air quality reflects its steel-industry legacy on Lake Ontario's harbour, with ArcelorMittal and Stelco operations contributing industrial PM2.5 and SO2 alongside vehicle traffic on the QEW, among Ontario's most industrially affected cities.
Today - 16 July | Pollution peaks at 11:00
AQI:
Fair
33.2/100
PM2.5 (fine particles):
Good
7.8/100
PM10 (coarse particles):
Good
4.5/100
NO2 (nitrogen dioxide):
Good
14.6/100
O3 (ozone):
Fair
33.2/100
SO2 (sulfur dioxide):
Good
0.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.8/100
PM1 (ultrafine particles):
Good
5.4/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 08:00
AQI:
Fair
27.6/100
PM2.5 (fine particles):
Good
5.0/100
PM10 (coarse particles):
Good
2.0/100
NO2 (nitrogen dioxide):
Good
10.4/100
O3 (ozone):
Fair
27.6/100
SO2 (sulfur dioxide):
Good
0.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.9/100
PM1 (ultrafine particles):
Good
3.6/100
Pollen forecast in Hamilton
View pollen forecastAir quality forecasts for neighbourhoods and landmarks in Hamilton
Sports venues in Hamilton
Frequently Asked Questions
Is air quality bad in Hamilton right now?
On 16 July 2026, overall air quality in Hamilton is fair. AQI is the main air quality indicator at 33.2/100. Pollution peaks around 11:00 AM (O3: 33.2/100).
Will air quality be worse tomorrow in Hamilton?
On 17 July 2026, air quality conditions in Hamilton will be similar to today, with AQI forecast at fair at 27.6/100. Pollution peaks around 8:00 AM (O3: 27.6/100).
When is air pollution at its worst in Hamilton?
Hamilton's air quality follows a seasonal rhythm tied to its steel mills along the harbourfront and the Niagara Escarpment above the city. Air quality here tends to dip in summer, when heat and industrial output combine, and again briefly in winter when cold, calm air traps emissions near ground level. Residents closer to the industrial waterfront tend to notice the seasonal swing more sharply than those higher up the escarpment.
Are air quality levels in Hamilton based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
Check air quality in other popular cities:
Data provided by Airmine — Last update: 16 July 2026 at 10:33 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
For long term forecasts and maps, see the Airmine app