Worst air pollution Monsanto, today and tomorrow
Today (20 September): Air quality in Monsanto is fair. AQI, PM2.5, O3, and PM1 are fair; PM10, NO2, SO2, CO, and HCHO are good. Pollution peaks around 10:00 AM (PM1: 23.1/100).
Tomorrow (21 September 2026): Air quality in Monsanto is fair. PM2.5 decreases to good; NO2 increases to fair; all other pollutants stay as today. Pollution peaks around 12:00 PM (NO2: 29.8/100). Airmine updates local air quality forecasts four times daily.
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Monsanto's setting on a granite hilltop in the Serra da Estrela foothills means minimal local traffic in the remote hill village drives most of the local variation in air quality across the year. The Castelo Branco terrain nearby can trap emissions under stable conditions, though stronger winds or rainfall usually bring noticeable improvement, and residents typically notice the clearest air during the more unsettled, windier stretches of the year.
Today - 20 September | Pollution peaks at 10:00
AQI:
Fair
23.1/100
PM2.5 (fine particles):
Fair
20.5/100
PM10 (coarse particles):
Good
16.5/100
NO2 (nitrogen dioxide):
Good
17.6/100
O3 (ozone):
Fair
22.7/100
SO2 (sulfur dioxide):
Good
1.6/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
3.2/100
PM1 (ultrafine particles):
Fair
23.1/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 12:00
AQI:
Fair
29.8/100
PM2.5 (fine particles):
Good
18.4/100
PM10 (coarse particles):
Good
14.4/100
NO2 (nitrogen dioxide):
Fair
29.8/100
O3 (ozone):
Fair
26.9/100
SO2 (sulfur dioxide):
Good
2.0/100
CO (carbon monoxide):
Good
0.6/100
HCHO (formaldehyde):
Good
5.1/100
PM1 (ultrafine particles):
Fair
21.9/100
Pollen forecast in Monsanto
View pollen forecastFrequently Asked Questions
Is air quality bad in Monsanto right now?
On 20 September 2026, overall air quality in Monsanto is fair. AQI is the main air quality indicator at 23.1/100. Pollution peaks around 10:00 AM (PM1: 23.1/100).
Will air quality be worse tomorrow in Monsanto?
On 21 September 2026, air quality conditions in Monsanto will be similar to today, with AQI forecast at fair at 29.8/100. Pollution peaks around 12:00 PM (NO2: 29.8/100).
When is air pollution at its worst in Monsanto?
The times to expect weaker air quality in Monsanto are during olive and oak pollen peaks and spells of minimal local traffic in the remote hill village; beyond those windows, conditions across Castelo Branco are typically steadier, particularly when wind or rain helps clear the air.
Are air quality levels in Monsanto 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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