Highest air pollution San Juan, today and tomorrow

Today (28 June): Air quality in San Juan is medium. AQI, PM2.5, and PM10 are medium; NO2, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 7:00 AM (PM10: 57.7/100).
Tomorrow (29 June 2026): Air quality in San Juan is medium. All pollutants stay as today. Pollution peaks around 8:00 AM (PM10: 53.5/100). 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

San Juan's air quality benefits from its exceptional Atlantic Ocean and San Juan Bay dual-coastal island position in Puerto Rico, with consistent northeast Atlantic and Caribbean trade winds providing outstanding maritime ventilation. Vehicle traffic on PR-18 and the surrounding metropolitan residential and commercial character contribute local sources, while the extraordinary Caribbean trade wind exposure generally maintains San Juan among the Caribbean's more reliably ventilated major metropolitan environments throughout most of the year.

Today - 28 June | Pollution peaks at 07:00

AQI:

Medium

57.7/100

PM2.5 (fine particles):

Medium

45.3/100

PM10 (coarse particles):

Medium

57.7/100

NO2 (nitrogen dioxide):

Good

0.1/100

O3 (ozone):

Good

15.9/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

1.8/100

PM1 (ultrafine particles):

Good

7.2/100

Levels show the poorest local air quality during the day

Tomorrow - 29 June | Pollution peaks at 08:00

AQI:

Medium

53.5/100

PM2.5 (fine particles):

Medium

43.1/100

PM10 (coarse particles):

Medium

53.5/100

NO2 (nitrogen dioxide):

Good

0.1/100

O3 (ozone):

Good

17.9/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

1.5/100

PM1 (ultrafine particles):

Good

6.6/100

Pollen forecast in San Juan

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Frequently Asked Questions

Is air quality bad in San Juan right now?

On 28 June 2026, overall air quality in San Juan is medium. AQI is the main air quality indicator at 57.7/100. Pollution peaks around 7:00 AM (PM10: 57.7/100).

Will air quality be worse tomorrow in San Juan?

On 29 June 2026, air quality conditions in San Juan will be similar to today, with AQI forecast at medium at 53.5/100. Pollution peaks around 8:00 AM (PM10: 53.5/100).

Are air quality levels in San Juan 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.

Check air quality in other popular cities:

Data provided by Airmine — Last update: 28 June 2026 at 18:37 CET (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

Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team