Worst air pollution Barreiro, today and tomorrow

Today (21 July): Air quality in Barreiro is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 3:00 PM (O3: 40.0/100).
Tomorrow (22 July 2026): Air quality in Barreiro is fair. All pollutants stay as today. Pollution peaks around 5:00 PM (O3: 33.7/100). 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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Barreiro's air quality reflects its position on the southern Tagus estuary bank opposite Lisbon, with the former Quimiparque chemical industrial complex legacy and vehicle traffic on the A2 motorway generating elevated industrial and traffic emissions. The Tagus estuary provides Atlantic ventilation, while the industrial legacy of the former chemical operations and the prevailing northwesterly winds generally carry Lisbon's urban emissions southward toward the Barreiro-Seixal shoreline on most days.

Today - 21 July | Pollution peaks at 15:00

AQI:

Fair

40.0/100

PM2.5 (fine particles):

Good

8.8/100

PM10 (coarse particles):

Good

7.3/100

NO2 (nitrogen dioxide):

Good

0/100

O3 (ozone):

Fair

40.0/100

SO2 (sulfur dioxide):

Good

0/100

CO (carbon monoxide):

Good

0/100

HCHO (formaldehyde):

Good

6.6/100

PM1 (ultrafine particles):

Good

6.2/100

Levels show the poorest local air quality during the day

Tomorrow - 22 July | Pollution peaks at 17:00

AQI:

Fair

33.7/100

PM2.5 (fine particles):

Good

9.4/100

PM10 (coarse particles):

Good

7.1/100

NO2 (nitrogen dioxide):

Good

0/100

O3 (ozone):

Fair

33.7/100

SO2 (sulfur dioxide):

Good

0/100

CO (carbon monoxide):

Good

0/100

HCHO (formaldehyde):

Good

3.0/100

PM1 (ultrafine particles):

Good

5.8/100

Pollen forecast in Barreiro

View pollen forecast

Frequently Asked Questions

Is air quality bad in Barreiro right now?

On 21 July 2026, overall air quality in Barreiro is fair. AQI is the main air quality indicator at 40.0/100. Pollution peaks around 3:00 PM (O3: 40.0/100).

Will air quality be worse tomorrow in Barreiro?

On 22 July 2026, air quality conditions in Barreiro will be similar to today, with AQI forecast at fair at 33.7/100. Pollution peaks around 5:00 PM (O3: 33.7/100).

When is air pollution at its worst in Barreiro?

You're most likely to spot worse air in Barreiro when estuary corridor pine and eucalyptus pollen peaks, or due to the former Quimiparque chemical industrial complex legacy and vehicle traffic on the A2 motorway; conditions generally improve once the season shifts and rainfall or stronger winds return.

Are air quality levels in Barreiro 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.

Why doesn’t the forecast always reflect wildfire impacts?

Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.

During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.

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Data provided by Airmine — Last update: 21 July 2026 at 16:20 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