Worst air pollution Iida, today and tomorrow

Today (16 July): Air quality in Iida is fair. PM2.5 and PM1 are fair; AQI, NO2, and O3 are medium; PM10, SO2, CO, and HCHO are good. Pollution peaks around 2:00 PM (O3: 45.1/100).
Tomorrow (17 July 2026): Air quality in Iida is fair. PM2.5 decreases to good; all other pollutants stay as today. Pollution peaks around 10:00 AM (O3: 54.8/100). 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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Iida's air quality reflects the Nagano Prefecture Ina Valley's partial enclosure between the Southern and Central Japanese Alps at 523 metres, with vehicle traffic on surrounding roads and the Fujitsu electronics, apple farming, and food processing corridor contributing local sources. The surrounding Honshu Alps create dramatic topographic enclosure, while winter valley inversions create seasonal challenges and summer conditions are generally excellent with clean alpine airflows throughout the warmer months.

Today - 16 July | Pollution peaks at 14:00

AQI:

Medium

45.1/100

PM2.5 (fine particles):

Fair

34.4/100

PM10 (coarse particles):

Good

10.0/100

NO2 (nitrogen dioxide):

Medium

41.8/100

O3 (ozone):

Medium

45.1/100

SO2 (sulfur dioxide):

Good

13.5/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

15.7/100

PM1 (ultrafine particles):

Fair

40.0/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 10:00

AQI:

Medium

54.8/100

PM2.5 (fine particles):

Good

16.3/100

PM10 (coarse particles):

Good

4.5/100

NO2 (nitrogen dioxide):

Medium

42.6/100

O3 (ozone):

Medium

54.8/100

SO2 (sulfur dioxide):

Good

6.6/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

19.9/100

PM1 (ultrafine particles):

Fair

21.9/100

Frequently Asked Questions

Is air quality bad in Iida right now?

On 16 July 2026, overall air quality in Iida is fair. PM1 is the main pollutant at 40.0/100. Pollution peaks around 2:00 PM (O3: 45.1/100).

Will air quality be worse tomorrow in Iida?

On 17 July 2026, air quality conditions in Iida will be similar to today, with PM1 forecast at fair at 21.9/100. Pollution peaks around 10:00 AM (O3: 54.8/100).

When is air pollution at its worst in Iida?

The biggest local contributors to pollution in Iida are traffic emissions, light manufacturing, together with agricultural activity, particularly once the surrounding valley traps air close to the ground. Topographic enclosure in the valley lets pollution accumulate rather than clear out. This is most pronounced in winter, when inversions are more frequent.

Are air quality levels in Iida 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