Worst air pollution Sarnia, today and tomorrow
Today (16 July): Air quality in Sarnia is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 12:00 PM (O3: 35.4/100).
Tomorrow (17 July 2026): Air quality in Sarnia is fair. All pollutants stay as today. Pollution peaks around 10:00 AM (O3: 33.6/100). 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
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Sarnia's air quality reflects its position in Ontario's Chemical Valley, with the petrochemical industrial cluster along the St. Clair River generating some of the province's highest industrial VOC and SO2 concentrations.
Today - 16 July | Pollution peaks at 12:00
AQI:
Fair
35.4/100
PM2.5 (fine particles):
Good
7.4/100
PM10 (coarse particles):
Good
6.3/100
NO2 (nitrogen dioxide):
Good
1.0/100
O3 (ozone):
Fair
35.4/100
SO2 (sulfur dioxide):
Good
0.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
5.6/100
PM1 (ultrafine particles):
Good
3.3/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 10:00
AQI:
Fair
33.6/100
PM2.5 (fine particles):
Good
6.6/100
PM10 (coarse particles):
Good
5.2/100
NO2 (nitrogen dioxide):
Good
0.7/100
O3 (ozone):
Fair
33.6/100
SO2 (sulfur dioxide):
Good
0.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.3/100
PM1 (ultrafine particles):
Good
3.8/100
Pollen forecast in Sarnia
View pollen forecastFrequently Asked Questions
Is air quality bad in Sarnia right now?
On 16 July 2026, overall air quality in Sarnia is fair. AQI is the main air quality indicator at 35.4/100. Pollution peaks around 12:00 PM (O3: 35.4/100).
Will air quality be worse tomorrow in Sarnia?
On 17 July 2026, air quality conditions in Sarnia will be similar to today, with AQI forecast at fair at 33.6/100. Pollution peaks around 10:00 AM (O3: 33.6/100).
When is air pollution at its worst in Sarnia?
The air over Sarnia varies through the year, influenced by the petrochemical refineries of "Chemical Valley" along the St. Clair River. 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. Wind direction along the river has a strong influence on which neighbourhoods feel the effects most on any given day.
Are air quality levels in Sarnia 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.
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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