Worst air pollution Thunder Bay, today and tomorrow
Today (16 July): Air quality in Thunder Bay is fair. NO2 is fair; AQI and O3 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 8:00 AM (O3: 50.9/100).
Tomorrow (17 July 2026): Air quality in Thunder Bay is fair. AQI worsens to fair; O3 increases to fair; all other pollutants stay as today. Pollution peaks around 9:00 AM (O3: 39.8/100). 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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Thunder Bay's air quality benefits from its remote Lake Superior shoreline position, with lake breezes providing reliable ventilation. Legacy pulp and paper industry and vehicle traffic contribute modest local sources.
Today - 16 July | Pollution peaks at 08:00
AQI:
Medium
50.9/100
PM2.5 (fine particles):
Good
11.4/100
PM10 (coarse particles):
Good
3.7/100
NO2 (nitrogen dioxide):
Fair
29.9/100
O3 (ozone):
Medium
50.9/100
SO2 (sulfur dioxide):
Good
3.3/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
7.0/100
PM1 (ultrafine particles):
Good
13.7/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 09:00
AQI:
Fair
39.8/100
PM2.5 (fine particles):
Good
8.9/100
PM10 (coarse particles):
Good
2.9/100
NO2 (nitrogen dioxide):
Fair
27.0/100
O3 (ozone):
Fair
39.8/100
SO2 (sulfur dioxide):
Good
3.4/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.3/100
PM1 (ultrafine particles):
Good
10.1/100
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Frequently Asked Questions
Is air quality bad in Thunder Bay right now?
On 16 July 2026, overall air quality in Thunder Bay is fair. NO2 is the main pollutant at 29.9/100. Pollution peaks around 8:00 AM (O3: 50.9/100).
Will air quality be worse tomorrow in Thunder Bay?
On 17 July 2026, air quality conditions in Thunder Bay will be similar to today, with AQI forecast at fair at 39.8/100. Pollution peaks around 9:00 AM (O3: 39.8/100).
When is air pollution at its worst in Thunder Bay?
The air over Thunder Bay varies through the year, influenced by its pulp-and-paper mills and position on the shore of Lake Superior. For much of the year the air is clean and forest-fresh, but summer and early autumn carry real risk of smoke episodes when wildfires burn nearby or further north. Local monitoring stations often see their highest readings of the year during major regional fire events.
Are air quality levels in Thunder Bay 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