Worst air pollution Castle Cary, today and tomorrow

On 20 September 2026, overall air quality in Castle Cary is fair. AQI is the main air quality indicator at 37.4/100. Pollution peaks around 10:00 PM (NO2: 37.4/100).

On 21 September 2026, air quality conditions in Castle Cary will be worse than today, with AQI forecast at moderate at 48.0/100. Pollution peaks around 8:00 PM (NO2: 48.0/100).

Seasons make a real difference to air quality in Castle Cary, more than most people realise. In summer, ozone can build up on sunny afternoons, though windier, warmer weather usually helps clear traffic-related pollution faster than in winter. Once the heating goes on and the air turns still, pollution from the A40 and nearby chimneys tends to build up rather than clear. The shoulder seasons generally bring the mildest readings of the year.

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.