Highest air pollution Seixal, today and tomorrow

Today (29 June): Air quality in Seixal is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 1:00 PM (O3: 35.7/100).
Tomorrow (30 June 2026): Air quality in Seixal is fair. All pollutants stay as today. Pollution peaks around 1:00 PM (O3: 38.0/100). 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

Seixal's air quality reflects its position on the southern bank of the Tagus estuary opposite Lisbon, with the Seixal industrial zone's steel and chemical operations and heavy traffic on the A2 contributing elevated PM2.5 and SO₂. The Tagus estuary generally provides ventilation from Atlantic westerlies, while the Arrábida Natural Park to the south provides a clean-air backdrop, and the prevailing northwesterly winds over the estuary generally carry Lisbon's urban emissions southward toward the Seixal and Almada shoreline.

Today - 29 June | Pollution peaks at 13:00

AQI:

Fair

35.7/100

PM2.5 (fine particles):

Good

8.6/100

PM10 (coarse particles):

Good

3.5/100

NO2 (nitrogen dioxide):

Good

0.3/100

O3 (ozone):

Fair

35.7/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

3.1/100

PM1 (ultrafine particles):

Good

6.1/100

Levels show the poorest local air quality during the day

Tomorrow - 30 June | Pollution peaks at 13:00

AQI:

Fair

38.0/100

PM2.5 (fine particles):

Good

8.4/100

PM10 (coarse particles):

Good

3.5/100

NO2 (nitrogen dioxide):

Good

0.4/100

O3 (ozone):

Fair

38.0/100

SO2 (sulfur dioxide):

Good

0.1/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

5.9/100

PM1 (ultrafine particles):

Good

6.4/100

Pollen forecast in Seixal

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Frequently Asked Questions

Is air quality bad in Seixal right now?

On 29 June 2026, overall air quality in Seixal is fair. AQI is the main air quality indicator at 35.7/100. Pollution peaks around 1:00 PM (O3: 35.7/100).

Will air quality be worse tomorrow in Seixal?

On 30 June 2026, air quality conditions in Seixal will be similar to today, with AQI forecast at fair at 38.0/100. Pollution peaks around 1:00 PM (O3: 38.0/100).

Are air quality levels in Seixal 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.

Want to see air quality forecasts for other cities in Portugal?

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Data provided by Airmine — Last update: 29 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