Worst air pollution Sants-Montjuïc - Barcelona, today and tomorrow

On 19 July 2026, overall air quality in Sants-Montjuïc is fair. PM2.5 is the main pollutant at 25.3/100. Pollution peaks around 3:00 PM (O3: 54.5/100).

On 20 July 2026, air quality conditions in Sants-Montjuïc will be similar to today, with PM2.5 forecast at fair at 20.2/100. Pollution peaks around 2:00 PM (O3: 58.6/100).

How do the seasons affect air quality in Sants-Montjuïc? Winter high-pressure systems tend to produce the year's worst episodes, as still air traps traffic fumes and heating smoke at ground level. Spring often marks a turning point, with increasing storminess and rainfall helping to clear accumulated exhaust and smoke from the air. The long, hot days of summer favour ozone build-up, which can spike on the stillest, sunniest afternoons. Air quality usually improves through autumn, as returning rains and cooling temperatures wash out summer's ozone and dust build-up. Being on the Mediterranean coast helps with dispersal most of the year, though summer tourism and North African dust episodes remain a factor.

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.