Worst air pollution Castro Urdiales, today and tomorrow

On 16 July 2026, overall air quality in Castro Urdiales is fair. AQI is the main air quality indicator at 33.2/100. Pollution peaks around 5:00 PM (O3: 33.2/100).

On 17 July 2026, air quality conditions in Castro Urdiales will be similar to today, with AQI forecast at fair at 27.6/100. Pollution peaks around 2:00 PM (O3: 27.6/100).

When is air quality typically worst in Castro Urdiales? Cold, windless spells in December and January are usually when conditions dip most, as heating emissions and traffic fumes accumulate under a stable atmosphere. Conditions tend to ease in spring, as more active weather systems bring the wind and rain needed to disperse ground-level pollution. The heat of summer drives up ozone formation, and dry conditions occasionally bring smoke from regional wildfires into the mix. Autumn generally marks the shift back toward calmer, cleaner conditions as temperatures drop and rainfall becomes more regular. This region's wetter, windier Atlantic climate generally keeps annual air quality more consistent than in Spain's drier interior and south.

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.