Worst air pollution Chiyoda-ku, today and tomorrow

Today (10 August): Air quality in Chiyoda-ku is fair. NO2 is fair; AQI and O3 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 1:00 PM (O3: 43.9/100).
Tomorrow (11 August 2026): Air quality in Chiyoda-ku is fair. AQI worsens to fair; NO2 decreases to good; O3 increases to fair; all other pollutants stay as today. Pollution peaks around 3:00 PM (O3: 38.4/100). Airmine updates local air quality forecasts four times daily.

Get the full experience in the Airmine app.

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

Follow your pollen exposure and performance with the free Airmine–Strava integration. See your pollen and air quality exposure for every Strava activity.

Chiyoda-ku's air quality reflects Tokyo's central government and imperial palace district, with vehicle traffic on surrounding expressways and the extraordinary concentration of national government ministries, Diet Building, and corporate headquarters generating sustained NO₂. The Imperial Palace park provides limited green space ventilation, while the broader Tokyo metropolitan regional background elevates all readings and summer photochemical ozone is the primary warm-season concern throughout the year.

Today - 10 August | Pollution peaks at 13:00

AQI:

Medium

43.9/100

PM2.5 (fine particles):

Good

12.8/100

PM10 (coarse particles):

Good

4.0/100

NO2 (nitrogen dioxide):

Fair

21.5/100

O3 (ozone):

Medium

43.9/100

SO2 (sulfur dioxide):

Good

15.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

8.8/100

PM1 (ultrafine particles):

Good

13.9/100

Levels show the poorest local air quality during the day

Tomorrow - 11 August | Pollution peaks at 15:00

AQI:

Fair

38.4/100

PM2.5 (fine particles):

Good

10.2/100

PM10 (coarse particles):

Good

2.8/100

NO2 (nitrogen dioxide):

Good

16.7/100

O3 (ozone):

Fair

38.4/100

SO2 (sulfur dioxide):

Good

11.5/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

7.8/100

PM1 (ultrafine particles):

Good

14.5/100

Frequently Asked Questions

Is air quality bad in Chiyoda-ku right now?

On 10 August 2026, overall air quality in Chiyoda-ku is fair. NO2 is the main pollutant at 21.5/100. Pollution peaks around 1:00 PM (O3: 43.9/100).

Will air quality be worse tomorrow in Chiyoda-ku?

On 11 August 2026, air quality conditions in Chiyoda-ku will be similar to today, with AQI forecast at fair at 38.4/100. Pollution peaks around 3:00 PM (O3: 38.4/100).

When is air pollution at its worst in Chiyoda-ku?

The biggest local contributors to pollution in Chiyoda-ku are traffic emissions along with heavy industry such as steel, cement, or petrochemical processing, particularly once warm, sunny weather takes hold. Strong sunlight reacting with local emissions drives up ground-level ozone. Cooler temperatures for the rest of the year keep this in check.

Are air quality levels in Chiyoda-ku 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.

Check air quality in other popular cities:

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.

Get the full experience in the Airmine app.