Highest air pollution Viana do Castelo, today and tomorrow
Today (29 June): Air quality in Viana do Castelo is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 PM (O3: 34.3/100).
Tomorrow (30 June 2026): Air quality in Viana do Castelo is fair. All pollutants stay as today. Pollution peaks around 6:00 PM (O3: 36.9/100). 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
Viana do Castelo's air quality benefits from its exceptional Atlantic and Lima river estuary position in the Minho region, with consistent Atlantic westerlies and the river estuary providing reliable maritime ventilation. Vehicle traffic on the A28 and surrounding industrial and port operations are the primary local sources, while the outstanding Atlantic coastal proximity and the Lima valley's ventilation corridor generally maintain Viana do Castelo among Portugal's cleaner northern urban environments.
Today - 29 June | Pollution peaks at 16:00
AQI:
Fair
34.3/100
PM2.5 (fine particles):
Good
4.5/100
PM10 (coarse particles):
Good
1.9/100
NO2 (nitrogen dioxide):
Good
5.2/100
O3 (ozone):
Fair
34.3/100
SO2 (sulfur dioxide):
Good
0.6/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
4.8/100
PM1 (ultrafine particles):
Good
3.5/100
Levels show the poorest local air quality during the day
Tomorrow - 30 June | Pollution peaks at 18:00
AQI:
Fair
36.9/100
PM2.5 (fine particles):
Good
3.0/100
PM10 (coarse particles):
Good
1.2/100
NO2 (nitrogen dioxide):
Good
5.2/100
O3 (ozone):
Fair
36.9/100
SO2 (sulfur dioxide):
Good
0.7/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
4.1/100
PM1 (ultrafine particles):
Good
1.9/100
Pollen forecast in Viana do Castelo
View pollen forecastFrequently Asked Questions
Is air quality bad in Viana do Castelo right now?
On 29 June 2026, overall air quality in Viana do Castelo is fair. AQI is the main air quality indicator at 34.3/100. Pollution peaks around 4:00 PM (O3: 34.3/100).
Will air quality be worse tomorrow in Viana do Castelo?
On 30 June 2026, air quality conditions in Viana do Castelo will be similar to today, with AQI forecast at fair at 36.9/100. Pollution peaks around 6:00 PM (O3: 36.9/100).
Are air quality levels in Viana do Castelo 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: 29 June 2026 at 18:39 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