Worst air pollution Caldas da Rainha, today and tomorrow
Today (20 September): Air quality in Caldas da Rainha is fair. AQI, PM2.5, NO2, and O3 are fair; PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 10:00 AM (NO2: 33.5/100).
Tomorrow (21 September 2026): Air quality in Caldas da Rainha is moderate. AQI worsens to moderate; NO2 increases to moderate; all other pollutants stay as today. Pollution peaks around 12:00 PM (NO2: 48.1/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Caldas da Rainha's air quality benefits from the Estremadura Atlantic coastal proximity in central Portugal, with consistent Atlantic westerlies providing reliable maritime ventilation. Vehicle traffic on the A8 motorway and surrounding ceramic, agriculture, and thermal spa operations contribute the primary local sources, while the Atlantic coastal proximity and the surrounding Torres Vedras-Óbidos hills generally maintain Caldas da Rainha among Portugal's more moderate central corridor urban environments throughout the year.
Today - 20 September | Pollution peaks at 10:00
AQI:
Fair
33.5/100
PM2.5 (fine particles):
Fair
30.3/100
PM10 (coarse particles):
Good
16.5/100
NO2 (nitrogen dioxide):
Fair
33.5/100
O3 (ozone):
Fair
31.8/100
SO2 (sulfur dioxide):
Good
1.6/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
3.2/100
PM1 (ultrafine particles):
Good
11.4/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 12:00
AQI:
Moderate
48.1/100
PM2.5 (fine particles):
Fair
27.4/100
PM10 (coarse particles):
Good
14.4/100
NO2 (nitrogen dioxide):
Moderate
48.1/100
O3 (ozone):
Fair
37.1/100
SO2 (sulfur dioxide):
Good
2.0/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
5.1/100
PM1 (ultrafine particles):
Good
10.6/100
Pollen forecast in Caldas da Rainha
View pollen forecastFrequently Asked Questions
Is air quality bad in Caldas da Rainha right now?
On 20 September 2026, overall air quality in Caldas da Rainha is fair. AQI is the main air quality indicator at 33.5/100. Pollution peaks around 10:00 AM (NO2: 33.5/100).
Will air quality be worse tomorrow in Caldas da Rainha?
On 21 September 2026, air quality conditions in Caldas da Rainha will be worse than today, with AQI forecast at moderate at 48.1/100. Pollution peaks around 12:00 PM (NO2: 48.1/100).
When is air pollution at its worst in Caldas da Rainha?
Residents in Caldas da Rainha are quickest to notice reduced air quality when pine and eucalyptus pollen peaks, or due to vehicle traffic on the A8 motorway and surrounding ceramic, agriculture, and thermal spa operations; for the rest of the year, natural airflow keeps background levels low.
Are air quality levels in Caldas da Rainha based on measurements or forecasts?
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.
Why doesn’t the forecast always reflect wildfire impacts?
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.
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Data provided by Airmine — Last update: 20 September 2026 at 20:27 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.
Some text on this page may be generated or summarised using artificial intelligence (AI). Wherever possible, AI-generated content is enriched with Airmine's proprietary data to improve its accuracy and relevance. However, AI-generated content may still contain errors, omissions, or inaccuracies.
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