Penafiel Air Quality Forecast - Today, Tomorrow
Air Quality Today
Today (11 October): Air quality in Penafiel is good. AQI, PM2.5, PM10, NO2, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 5:00 PM (O3: 13.8/100).
Air Quality Tomorrow
Tomorrow (12 October 2026): Air quality in Penafiel is fair. AQI worsens to fair; PM1 increases to fair; all other pollutants stay as today. Pollution peaks around 10:00 PM (PM1: 21.9/100).
Explore Forecasts
Pollen & Mold
Air Quality in Other Cities
Pollen in Other Cities
Get More in Our App
Local pollen and air quality forecasts, interactive pollen maps and route profiles
Features and forecast availability vary by region.
Air Quality
Today - 11 October
| Pollutant | Level | Value |
|---|---|---|
| AQI | Good | 13.8/100 |
| PM2.5 (fine particles) | Good | 4.2/100 |
| PM10 (coarse particles) | Good | 5.0/100 |
| NO2 (nitrogen dioxide) | Good | 7.0/100 |
| O3 (ozone) | Good | 13.8/100 |
| SO2 (sulfur dioxide) | Good | 0.7/100 |
| CO (carbon monoxide) | Good | 0.5/100 |
| HCHO (formaldehyde) | Good | 3.4/100 |
| PM1 (ultrafine particles) | Good | 12.3/100 |
Tomorrow - 12 October
| Pollutant | Level | Value |
|---|---|---|
| AQI | Fair | 21.9/100 |
| PM2.5 (fine particles) | Good | 7.9/100 |
| PM10 (coarse particles) | Good | 8.1/100 |
| NO2 (nitrogen dioxide) | Good | 9.8/100 |
| O3 (ozone) | Good | 14.1/100 |
| SO2 (sulfur dioxide) | Good | 0.7/100 |
| CO (carbon monoxide) | Good | 0.5/100 |
| HCHO (formaldehyde) | Good | 3.5/100 |
| PM1 (ultrafine particles) | Fair | 21.9/100 |
Local Environmental Conditions
The heart of Penafiel combines built-up streets with more open land, so local traffic matters, though emissions are less concentrated than in a city center. Its setting in a valley at around 240 m means cold air and pollution can get trapped close to the ground during calm spells. Traffic on the A4 motorway adds to local emissions.
Calm, cold weather in January, averaging 7°C, lets the valley fill with pollution from home heating and traffic overnight. In the warmer months, hot afternoons from July to August, averaging 23°C in the warmest month, are when ozone is most likely to build up. Wildfire smoke is most likely from July to August, sometimes turning the sky hazy for days.
Get pollen & AQ on Strava
Follow your environmental exposure and performance with the free Airmine-Strava integration. See your pollen and air quality exposure for every Strava activity.
Resource Hub
Frequently Asked Questions About Air Quality in Porto
Is air quality bad in Penafiel right now?
On 11 October 2026, overall air quality in Penafiel is good. AQI is the main air quality indicator at 13.8/100. Pollution peaks around 5:00 PM (O3: 13.8/100).
Will air quality be worse tomorrow in Penafiel?
On 12 October 2026, air quality conditions in Penafiel will be worse than today, with AQI forecast at fair at 21.9/100. Pollution peaks around 10:00 PM (PM1: 21.9/100).
When is air pollution at its worst in Penafiel?
Calm, cold weather in January, averaging 7°C, lets the valley fill with pollution from home heating and traffic overnight. In the warmer months, hot afternoons from July to August, averaging 23°C in the warmest month, are when ozone is most likely to build up. Wildfire smoke is most likely from July to August, sometimes turning the sky hazy for days.
Are air quality levels in Penafiel 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.
Understanding the Scale
The 0–100 air quality scores represent risk levels, not direct air pollutant concentrations. Higher scores indicate higher risk.
Air Quality
| Good | 0-20 | Low air quality risk. Air quality is expected to be good, with low levels of pollution. |
| Fair | 20-40 | Generally low air quality risk. Air quality is expected to be acceptable, with some pollution present. |
| Moderate | 40-60 | Moderate air quality risk. Air pollution is elevated and air quality may be less favorable. |
| Poor | 60-80 | High air quality risk. Air pollution is high and air quality is expected to be poor. |
| Very Poor | 80-100 | Very high air quality risk. Air pollution is very high and air quality is expected to be very poor. |