Worst air pollution Onomichi, today and tomorrow
Today (16 July): Air quality in Onomichi is poor. AQI and O3 are poor; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 3:00 PM (O3: 63.8/100).
Tomorrow (17 July 2026): Air quality in Onomichi is very poor. AQI worsens to very poor; PM2.5 increases to fair; O3 increases to very poor; PM1 increases to fair; all other pollutants stay as today. Pollution peaks around 2:00 PM (O3: 100/100). 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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Onomichi's air quality reflects the Hiroshima Prefecture Seto Inland Sea coastal position on the Onomichi Suido channel, with vehicle traffic on surrounding roads and the shipbuilding, tourism, and services corridor contributing local sources. Consistent Seto Inland Sea maritime breezes provide coastal ventilation, while the hillside city's dramatic topographic character creates distinctive local wind patterns and Onomichi generally maintains moderate to good conditions for a historic Japanese Seto Inland Sea coastal city throughout most of the year.
Today - 16 July | Pollution peaks at 15:00
AQI:
Poor
63.8/100
PM2.5 (fine particles):
Good
11.2/100
PM10 (coarse particles):
Good
3.4/100
NO2 (nitrogen dioxide):
Good
8.6/100
O3 (ozone):
Poor
63.8/100
SO2 (sulfur dioxide):
Good
2.2/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
14.6/100
PM1 (ultrafine particles):
Good
13.9/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 14:00
AQI:
Very poor
100/100
PM2.5 (fine particles):
Fair
27.8/100
PM10 (coarse particles):
Good
8.6/100
NO2 (nitrogen dioxide):
Good
8.2/100
O3 (ozone):
Very poor
100/100
SO2 (sulfur dioxide):
Good
4.1/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
15.5/100
PM1 (ultrafine particles):
Fair
33.2/100
Frequently Asked Questions
Is air quality bad in Onomichi right now?
On 16 July 2026, overall air quality in Onomichi is poor. AQI is the main air quality indicator at 63.8/100. Pollution peaks around 3:00 PM (O3: 63.8/100).
Will air quality be worse tomorrow in Onomichi?
On 17 July 2026, air quality conditions in Onomichi will be worse than today, with AQI forecast at very poor at 100/100. Pollution peaks around 2:00 PM (O3: 100/100).
When is air pollution at its worst in Onomichi?
In Onomichi, traffic on the surrounding roads, shipbuilding and port operations, together with seasonal tourism traffic are the main local sources, with conditions worsening when maritime winds die down. Maritime airflow normally ventilates the area well, though calmer spells let levels rise. Areas further inland without this ventilation tend to fare worse.
Are air quality levels in Onomichi 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