Worst air pollution California's Great America - San Jose, today and tomorrow

Today (15 July): Air quality in California's Great America is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 9:00 AM (O3: 45.8/100).
Tomorrow (16 July 2026): Air quality in California's Great America is fair. PM2.5 increases to fair; all other pollutants stay as today. Pollution peaks around 9:00 AM (O3: 44.7/100). 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 Jose's California's Great America air quality reflects the Santa Clara Valley's partial topographic enclosure in Silicon Valley, with concentrated visitor vehicle traffic on US-101 and the surrounding technology campus corridor contributing elevated NOₓ during peak summer periods. Bay Delta breezes provide afternoon ventilation, while the park's suburban character and the Silicon Valley's moderate background generally maintain reasonable conditions during non-peak periods throughout most of the year.

Today - 15 July | Pollution peaks at 09:00

AQI:

Medium

45.8/100

PM2.5 (fine particles):

Good

15.8/100

PM10 (coarse particles):

Good

9.9/100

NO2 (nitrogen dioxide):

Good

10.5/100

O3 (ozone):

Medium

45.8/100

SO2 (sulfur dioxide):

Good

3.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

2.6/100

PM1 (ultrafine particles):

Good

9.6/100

Levels show the poorest local air quality during the day

Tomorrow - 16 July | Pollution peaks at 09:00

AQI:

Medium

44.7/100

PM2.5 (fine particles):

Fair

20.5/100

PM10 (coarse particles):

Good

10.3/100

NO2 (nitrogen dioxide):

Good

17.3/100

O3 (ozone):

Medium

44.7/100

SO2 (sulfur dioxide):

Good

3.2/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

2.2/100

PM1 (ultrafine particles):

Good

13.1/100

Other Landmarks in San Jose

Sports venues in San Jose

Frequently Asked Questions

Is air quality bad in California's Great America right now?

On 15 July 2026, overall air quality in California's Great America is medium. AQI is the main air quality indicator at 45.8/100. Pollution peaks around 9:00 AM (O3: 45.8/100).

Will air quality be worse tomorrow in California's Great America?

On 16 July 2026, air quality conditions in California's Great America will be worse than today, with PM2.5 forecast at fair at 20.5/100. Pollution peaks around 9:00 AM (O3: 44.7/100).

When is air pollution at its worst in California's Great America?

California's Great America's air quality follows a clear seasonal pattern. Typically, late winter and spring tend to have the cleanest conditions, once winter rains settle in, while the long dry stretch from midsummer into autumn brings both ozone and wildfire smoke risk. Dry summer conditions with virtually no rain mean pollution and smoke can linger for extended stretches once they arrive.

Are air quality levels in California's Great America 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