Worst air pollution Casa Loma - Toronto, today and tomorrow

Today (16 July): Air quality in Casa Loma is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 10:00 AM (O3: 32.0/100).
Tomorrow (17 July 2026): Air quality in Casa Loma is fair. All pollutants stay as today. Pollution peaks around 8:00 AM (O3: 29.1/100). 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.

Casa Loma's air quality benefits from its elevated hillside position above midtown Toronto, with the castle's gardens providing some green buffering from surrounding residential street traffic.

Today - 16 July | Pollution peaks at 10:00

AQI:

Fair

32.0/100

PM2.5 (fine particles):

Good

6.4/100

PM10 (coarse particles):

Good

4.1/100

NO2 (nitrogen dioxide):

Good

1.8/100

O3 (ozone):

Fair

32.0/100

SO2 (sulfur dioxide):

Good

0.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

4.3/100

PM1 (ultrafine particles):

Good

4.4/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 08:00

AQI:

Fair

29.1/100

PM2.5 (fine particles):

Good

4.9/100

PM10 (coarse particles):

Good

2.0/100

NO2 (nitrogen dioxide):

Good

1.9/100

O3 (ozone):

Fair

29.1/100

SO2 (sulfur dioxide):

Good

0.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

3.0/100

PM1 (ultrafine particles):

Good

3.5/100

Other Landmarks in Toronto

Sports venues in Toronto

Frequently Asked Questions

Is air quality bad in Casa Loma right now?

On 16 July 2026, overall air quality in Casa Loma is fair. AQI is the main air quality indicator at 32.0/100. Pollution peaks around 10:00 AM (O3: 32.0/100).

Will air quality be worse tomorrow in Casa Loma?

On 17 July 2026, air quality conditions in Casa Loma will be similar to today, with AQI forecast at fair at 29.1/100. Pollution peaks around 8:00 AM (O3: 29.1/100).

When is air pollution at its worst in Casa Loma?

Seasonal air quality in Casa Loma is closely linked to its hilltop setting above midtown Toronto's tree-lined streets. 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. Because the area sits downwind of denser Toronto traffic, conditions can still worsen on hot, windless afternoons.

Are air quality levels in Casa Loma 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