Worst air pollution Hannō, today and tomorrow
Today (16 July): Air quality in Hannō is poor. AQI and O3 are poor; PM2.5, NO2, and PM1 are fair; PM10, SO2, CO, and HCHO are good. Pollution peaks around 3:00 PM (O3: 77.7/100).
Tomorrow (17 July 2026): Air quality in Hannō is fair. AQI improves to medium; O3 decreases to medium; HCHO increases to fair; all other pollutants stay as today. Pollution peaks around 1:00 PM (O3: 50.3/100). 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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Hannō's air quality reflects the Saitama Prefecture Iruma River valley position at the Okutama highlands gateway, with vehicle traffic on surrounding roads and the manufacturing, residential, and mountain gateway character contributing local sources. The surrounding Chichibu highlands create topographic variation, while the broader Tokyo metropolitan regional background and summer photochemical ozone are the primary air quality concerns and Hanno generally maintains moderate to good Tokyo northwestern mountain gateway readings throughout most of the year.
Today - 16 July | Pollution peaks at 15:00
AQI:
Poor
77.7/100
PM2.5 (fine particles):
Fair
29.8/100
PM10 (coarse particles):
Good
8.8/100
NO2 (nitrogen dioxide):
Fair
23.1/100
O3 (ozone):
Poor
77.7/100
SO2 (sulfur dioxide):
Good
17.3/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
11.9/100
PM1 (ultrafine particles):
Fair
34.1/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 13:00
AQI:
Medium
50.3/100
PM2.5 (fine particles):
Fair
20.3/100
PM10 (coarse particles):
Good
5.5/100
NO2 (nitrogen dioxide):
Fair
25.6/100
O3 (ozone):
Medium
50.3/100
SO2 (sulfur dioxide):
Good
14.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Fair
20.5/100
PM1 (ultrafine particles):
Fair
26.0/100
Frequently Asked Questions
Is air quality bad in Hannō right now?
On 16 July 2026, overall air quality in Hannō is poor. AQI is the main air quality indicator at 77.7/100. Pollution peaks around 3:00 PM (O3: 77.7/100).
Will air quality be worse tomorrow in Hannō?
On 17 July 2026, air quality conditions in Hannō will be better than today, with PM1 forecast at fair at 26.0/100. Pollution peaks around 1:00 PM (O3: 50.3/100).
When is air pollution at its worst in Hannō?
Pollution in Hannō typically rises when vehicle traffic, steel, cement, and chemical production, as well as textile and manufacturing operations combine, especially once warm, sunny weather takes hold. Photochemical reactions in the heat push ozone levels higher. Cooler temperatures for the rest of the year keep this in check.
Are air quality levels in Hannō 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