Worst air pollution San Ramon, today and tomorrow
Today (15 July): Air quality in San Ramon is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 8:00 AM (O3: 39.4/100).
Tomorrow (16 July 2026): Air quality in San Ramon is medium. AQI improves to medium; O3 decreases to medium; all other pollutants stay as today. Pollution peaks around 10:00 AM (O3: 41.0/100). 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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San Ramon's air quality reflects the Diablo Valley's position in the San Francisco Bay Area's eastern corridor, with vehicle emissions from I-680 the primary local source. The San Ramon Valley's partial topographic enclosure between the Diablo Range and the Las Trampas hills creates periodic temperature inversion episodes, while summer wildfire smoke from surrounding East Bay hills is an increasingly frequent seasonal concern throughout the year.
Today - 15 July | Pollution peaks at 08:00
AQI:
Fair
39.4/100
PM2.5 (fine particles):
Good
11.4/100
PM10 (coarse particles):
Good
7.0/100
NO2 (nitrogen dioxide):
Good
0.1/100
O3 (ozone):
Fair
39.4/100
SO2 (sulfur dioxide):
Good
0.0/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.2/100
PM1 (ultrafine particles):
Good
6.3/100
Levels show the poorest local air quality during the day
Tomorrow - 16 July | Pollution peaks at 10:00
AQI:
Medium
41.0/100
PM2.5 (fine particles):
Good
15.8/100
PM10 (coarse particles):
Good
7.7/100
NO2 (nitrogen dioxide):
Good
0.2/100
O3 (ozone):
Medium
41.0/100
SO2 (sulfur dioxide):
Good
0.0/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
1.9/100
PM1 (ultrafine particles):
Good
10.5/100
Pollen forecast in San Ramon
View pollen forecastFrequently Asked Questions
Is air quality bad in San Ramon right now?
On 15 July 2026, overall air quality in San Ramon is fair. AQI is the main air quality indicator at 39.4/100. Pollution peaks around 8:00 AM (O3: 39.4/100).
Will air quality be worse tomorrow in San Ramon?
On 16 July 2026, air quality conditions in San Ramon will be better than today, with AQI forecast at medium at 41.0/100. Pollution peaks around 10:00 AM (O3: 41.0/100).
When is air pollution at its worst in San Ramon?
Air quality in San Ramon shifts across the year: the cleanest air usually comes in winter, when storms periodically flush pollution out of the basin, but from August into October, wildfire smoke can add sharp particulate spikes on top of the usual summer ozone. Coastal breezes offer some relief compared to inland valley locations that see heavier smog buildup.
Are air quality levels in San Ramon 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