Worst air pollution Siegen, today and tomorrow

On 21 July 2026, overall air quality in Siegen is fair. AQI is the main air quality indicator at 28.9/100. Pollution peaks around 6:00 PM (O3: 28.9/100).

On 22 July 2026, air quality conditions in Siegen will be similar to today, with AQI forecast at fair at 20.2/100. Pollution peaks around 5:00 PM (O3: 20.2/100).

Residents in Siegen are most likely to notice reduced air quality when hornbeam, birch, and spruce pollen peaks, or on calm, hot days when local sources build up; nearby road traffic adds a modest, steady local contribution. This region typically sees only a light ragweed presence in late summer. Early mornings after overnight rain usually offer the freshest air.

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.