Worst air pollution Penafiel, today and tomorrow
Today (20 September): Air quality in Penafiel is fair. AQI and PM1 are fair; PM2.5, PM10, NO2, O3, SO2, CO, and HCHO are good. Pollution peaks around 8:00 AM (PM1: 24.7/100).
Tomorrow (21 September 2026): Air quality in Penafiel is good. AQI improves to good; PM1 decreases to good; all other pollutants stay as today. Pollution peaks around 3:00 PM (O3: 18.7/100). 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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Penafiel's air quality reflects the Sousa river valley in the Porto metropolitan area's northeastern corridor, with vehicle traffic on the A4 motorway and the surrounding granite quarrying, furniture, and agribusiness contributing local sources. Atlantic westerlies generally provide maritime ventilation, while the surrounding Douro valley hills create topographic variation and granite quarrying dust adds a distinctive local PM10 contribution to the Penafiel municipal air quality profile.
Today - 20 September | Pollution peaks at 08:00
AQI:
Fair
24.7/100
PM2.5 (fine particles):
Good
9.8/100
PM10 (coarse particles):
Good
11.1/100
NO2 (nitrogen dioxide):
Good
9.1/100
O3 (ozone):
Good
18.2/100
SO2 (sulfur dioxide):
Good
0.4/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
3.3/100
PM1 (ultrafine particles):
Fair
24.7/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 15:00
AQI:
Good
18.7/100
PM2.5 (fine particles):
Good
9.1/100
PM10 (coarse particles):
Good
10.8/100
NO2 (nitrogen dioxide):
Good
9.1/100
O3 (ozone):
Good
18.7/100
SO2 (sulfur dioxide):
Good
0.8/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
5.1/100
PM1 (ultrafine particles):
Good
17.7/100
Pollen forecast in Penafiel
View pollen forecastFrequently Asked Questions
Is air quality bad in Penafiel right now?
On 20 September 2026, overall air quality in Penafiel is fair. AQI is the main air quality indicator at 24.7/100. Pollution peaks around 8:00 AM (PM1: 24.7/100).
Will air quality be worse tomorrow in Penafiel?
On 21 September 2026, air quality conditions in Penafiel will be better than today, with AQI forecast at good at 18.7/100. Pollution peaks around 3:00 PM (O3: 18.7/100).
When is air pollution at its worst in Penafiel?
In Penafiel, reduced air quality is most noticeable when local tree and grass pollen peaks, and on days affected by vehicle traffic on the A4 motorway and the nearby granite quarrying, furniture, and agribusiness; the picture usually improves again once the season turns.
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.
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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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