Worst air pollution Ottawa, today and tomorrow

Today (9 August): Air quality in Ottawa is fair. AQI, NO2, and O3 are fair; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 9:00 AM (O3: 37.5/100).
Tomorrow (10 August 2026): Air quality in Ottawa is fair. All pollutants stay as today. Pollution peaks around 11:00 AM (O3: 35.9/100). Airmine updates local air quality forecasts four times daily.

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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team

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Ottawa's air quality benefits from its position away from heavy industry, with vehicle traffic on the 417 the primary local source. The Ottawa River valley provides reasonable ventilation, while winter wood burning adds seasonal PM2.5.

Today - 9 August | Pollution peaks at 09:00

AQI:

Fair

37.5/100

PM2.5 (fine particles):

Good

9.4/100

PM10 (coarse particles):

Good

6.1/100

NO2 (nitrogen dioxide):

Fair

23.1/100

O3 (ozone):

Fair

37.5/100

SO2 (sulfur dioxide):

Good

1.7/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

9.7/100

PM1 (ultrafine particles):

Good

6.6/100

Levels show the poorest local air quality during the day

Tomorrow - 10 August | Pollution peaks at 11:00

AQI:

Fair

35.9/100

PM2.5 (fine particles):

Good

12.1/100

PM10 (coarse particles):

Good

7.7/100

NO2 (nitrogen dioxide):

Fair

28.3/100

O3 (ozone):

Fair

35.9/100

SO2 (sulfur dioxide):

Good

1.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

6.8/100

PM1 (ultrafine particles):

Good

9.3/100

Pollen forecast in Ottawa

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Air quality forecasts for neighbourhoods and landmarks in Ottawa

Sports venues in Ottawa

Frequently Asked Questions

Is air quality bad in Ottawa right now?

On 9 August 2026, overall air quality in Ottawa is fair. AQI is the main air quality indicator at 37.5/100. Pollution peaks around 9:00 AM (O3: 37.5/100).

Will air quality be worse tomorrow in Ottawa?

On 10 August 2026, air quality conditions in Ottawa will be similar to today, with AQI forecast at fair at 35.9/100. Pollution peaks around 11:00 AM (O3: 35.9/100).

When is air pollution at its worst in Ottawa?

The air over Ottawa varies through the year, influenced by its mix of government offices, the Rideau Canal corridor and surrounding forest. The warmest months typically see the poorest air quality, with heat and heavy traffic driving up smog levels on windless days, whereas fall and winter tend to bring cleaner, more variable conditions. The surrounding Greenbelt helps buffer some neighbourhoods, though downtown corridors still see the sharpest seasonal shifts.

Are air quality levels in Ottawa 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.

Why doesn’t the forecast always reflect wildfire impacts?

Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.

During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.

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Data provided by Airmine — Last update: 9 August 2026 at 20:27 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.

Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.

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