Worst air pollution San Antonio, today and tomorrow

Today (16 July): Air quality in San Antonio is good. AQI, PM2.5, PM10, NO2, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 10:00 PM (O3: 12.1/100).
Tomorrow (17 July 2026): Air quality in San Antonio is good. All pollutants stay as today. Pollution peaks around 11:00 PM (O3: 16.9/100). 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 Antonio in Valparaíso reflects the Chilean central Pacific coastal position on the Maipo River delta, with vehicle traffic on surrounding roads and the major ENAP refinery, port operations, and industrial corridor generating elevated industrial SO₂ and VOCs. Consistent Pacific Humboldt Current maritime breezes provide ventilation, while the ENAP refinery's industrial scale represents San Antonio's most distinctive local air quality contribution and the outstanding Pacific coastal exposure generally manages readings on most wind days throughout the year.

Today - 16 July | Pollution peaks at 22:00

AQI:

Good

12.1/100

PM2.5 (fine particles):

Good

7.4/100

PM10 (coarse particles):

Good

3.4/100

NO2 (nitrogen dioxide):

Good

0.1/100

O3 (ozone):

Good

12.1/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

0.4/100

PM1 (ultrafine particles):

Good

1.4/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 23:00

AQI:

Good

16.9/100

PM2.5 (fine particles):

Good

8.0/100

PM10 (coarse particles):

Good

3.7/100

NO2 (nitrogen dioxide):

Good

0.1/100

O3 (ozone):

Good

16.9/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

0.3/100

PM1 (ultrafine particles):

Good

1.5/100

Frequently Asked Questions

Is air quality bad in San Antonio right now?

On 16 July 2026, overall air quality in San Antonio is good. AQI is the main air quality indicator at 12.1/100. Pollution peaks around 10:00 PM (O3: 12.1/100).

Will air quality be worse tomorrow in San Antonio?

On 17 July 2026, air quality conditions in San Antonio will be similar to today, with AQI forecast at good at 16.9/100. Pollution peaks around 11:00 PM (O3: 16.9/100).

When is air pollution at its worst in San Antonio?

In San Antonio, traffic on the surrounding roads, heavy industry such as steel, cement, or petrochemical processing, as well as harbour and shipping traffic are the main local sources, with conditions worsening when windblown dust events occur. These wind events can carry dust in from the surrounding arid landscape. Maritime airflow normally ventilates the area well, though calmer spells let levels rise.

Are air quality levels in San Antonio 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