Highest air pollution Castelo Branco, today and tomorrow

Today (29 June): Air quality in Castelo Branco is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 PM (O3: 41.1/100).
Tomorrow (30 June 2026): Air quality in Castelo Branco is medium. All pollutants stay as today. Pollution peaks around 3:00 PM (O3: 43.6/100). 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

Castelo Branco's air quality benefits from its elevated Beira Baixa position at 379 metres near the Spanish border, with consistent Atlantic westerlies providing reliable ventilation across the flat Tagus interior plateau. Vehicle traffic on the A23 motorway and the surrounding agricultural and light manufacturing operations contribute the primary local sources, while the open Iberian plateau and Atlantic westerlies generally maintain Castelo Branco among Portugal's more moderate interior regional capital environments throughout the year.

Today - 29 June | Pollution peaks at 16:00

AQI:

Medium

41.1/100

PM2.5 (fine particles):

Good

9.4/100

PM10 (coarse particles):

Good

4.2/100

NO2 (nitrogen dioxide):

Good

15.4/100

O3 (ozone):

Medium

41.1/100

SO2 (sulfur dioxide):

Good

2.8/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

4.4/100

PM1 (ultrafine particles):

Good

7.1/100

Levels show the poorest local air quality during the day

Tomorrow - 30 June | Pollution peaks at 15:00

AQI:

Medium

43.6/100

PM2.5 (fine particles):

Good

11.8/100

PM10 (coarse particles):

Good

4.9/100

NO2 (nitrogen dioxide):

Good

18.0/100

O3 (ozone):

Medium

43.6/100

SO2 (sulfur dioxide):

Good

3.5/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

4.7/100

PM1 (ultrafine particles):

Good

8.6/100

Pollen forecast in Castelo Branco

View pollen forecast

Frequently Asked Questions

Is air quality bad in Castelo Branco right now?

On 29 June 2026, overall air quality in Castelo Branco is medium. AQI is the main air quality indicator at 41.1/100. Pollution peaks around 4:00 PM (O3: 41.1/100).

Will air quality be worse tomorrow in Castelo Branco?

On 30 June 2026, air quality conditions in Castelo Branco will be similar to today, with AQI forecast at medium at 43.6/100. Pollution peaks around 3:00 PM (O3: 43.6/100).

Are air quality levels in Castelo Branco 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