Worst air pollution Santiago de Compostela, today and tomorrow

On 19 July 2026, overall air quality in Santiago de Compostela is medium. AQI is the main air quality indicator at 55.5/100. Pollution peaks around 7:00 PM (O3: 55.5/100).

On 20 July 2026, air quality conditions in Santiago de Compostela will be similar to today, with AQI forecast at medium at 56.2/100. Pollution peaks around 7:00 PM (O3: 56.2/100).

How does air quality change throughout the year in Santiago de Compostela? The winter months typically bring the weakest air quality of the year, as calm anticyclonic conditions trap vehicle and heating pollution near the surface. Spring is typically a transitional season, as milder, windier weather starts clearing out the pollutants that accumulate during winter's calm spells. Summer readings are shaped mainly by ozone, which builds under strong sun and heat, sometimes worsened by drifting wildfire smoke. Autumn generally marks the shift back toward calmer, cleaner conditions as temperatures drop and rainfall becomes more regular. The Atlantic north's frequent rain and strong onshore winds generally keep year-round levels lower than in the drier interior and south.

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.

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.