Worst air pollution South San Francisco, today and tomorrow
Today (15 July): Air quality in South San Francisco 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 South San Francisco 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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South San Francisco's air quality benefits from the San Francisco Bay Peninsula's consistent marine layer and Bay breezes providing reliable maritime ventilation across this major biopharmaceutical industry hub. Vehicle emissions from US-101 and the Genentech and surrounding biotechnology campus operations contribute local sources, while the bay's open geometry provides good ventilation and summer wildfire smoke from surrounding Bay Area 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
13.1/100
PM10 (coarse particles):
Good
8.1/100
NO2 (nitrogen dioxide):
Good
3.4/100
O3 (ozone):
Fair
39.4/100
SO2 (sulfur dioxide):
Good
1.5/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.2/100
PM1 (ultrafine particles):
Good
7.2/100
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
18.2/100
PM10 (coarse particles):
Good
8.9/100
NO2 (nitrogen dioxide):
Good
7.4/100
O3 (ozone):
Medium
41.0/100
SO2 (sulfur dioxide):
Good
1.5/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
1.9/100
PM1 (ultrafine particles):
Good
12.0/100
Pollen forecast in South San Francisco
View pollen forecastFrequently Asked Questions
Is air quality bad in South San Francisco right now?
On 15 July 2026, overall air quality in South San Francisco 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 South San Francisco?
On 16 July 2026, air quality conditions in South San Francisco 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 South San Francisco?
Seasonal changes shape air quality across South San Francisco. Typically, late winter and spring tend to have the cleanest conditions, once winter rains settle in, while summer and early autumn bring the highest risk, with heat-driven ozone and wildfire smoke both peaking from July through October. Wine country and inland valley locations tend to see more smoke buildup than the immediate coast.
Are air quality levels in South San Francisco 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