Worst air pollution Alphen aan den Rijn, today and tomorrow

On 20 September 2026, overall air quality in Alphen aan den Rijn is fair. AQI is the main air quality indicator at 29.4/100. Pollution peaks around 5:00 PM (O3: 29.4/100).

On 21 September 2026, air quality conditions in Alphen aan den Rijn will be similar to today, with AQI forecast at fair at 24.8/100. Pollution peaks around 4:00 PM (O3: 24.8/100).

The main times to watch for Alphen aan den Rijn are the birch, oak, and alder pollen peak over the spring and early-summer period, and hot, still days when local traffic on the N11 and industry emissions build up; onshore winds across the delta typically keep pollutants from settling. Outside of these periods, conditions in Alphen aan den Rijn are typically close to the Dutch national average.

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.