Worst air pollution San Fernando, today and tomorrow

On 9 August 2026, overall air quality in San Fernando is fair. AQI is the main air quality indicator at 38.9/100. Pollution peaks around 6:00 PM (O3: 38.9/100).

On 10 August 2026, air quality conditions in San Fernando will be similar to today, with PM2.5 forecast at fair at 23.5/100. Pollution peaks around 6:00 PM (O3: 40.4/100).

Does air quality in San Fernando vary by season? Winter high-pressure systems tend to produce the year's worst episodes, as still air traps traffic fumes and heating smoke at ground level. As spring progresses, wetter and windier conditions generally help flush out the traffic and heating pollution that built up over winter. Hot, dry summer conditions favour ozone formation, so afternoon readings can rise even when traffic and heating pollution are otherwise low. Autumn usually sees a steady return to cleaner conditions as the ozone-favouring heat of summer fades and rainfall picks up. This area's proximity to North Africa means Saharan dust episodes can arrive at almost any time of year, layering onto the seasonal pattern.

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.