Worst air pollution Alphen aan den Rijn, today and tomorrow

Today (21 July): Air quality in Alphen aan den Rijn is fair. O3 is fair; AQI and NO2 are medium; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 6:00 AM (NO2: 44.8/100).
Tomorrow (22 July 2026): Air quality in Alphen aan den Rijn is fair. AQI worsens to fair; NO2 increases to fair; O3 decreases to good; all other pollutants stay as today. Pollution peaks around 5:00 AM (NO2: 28.9/100). Airmine updates local air quality forecasts four times daily.

For long term forecasts and maps, see the Airmine app

Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team

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Alphen aan den Rijn's air quality reflects the Dutch Randstad Green Heart between Amsterdam and Rotterdam, with vehicle traffic on the N11 and surrounding greenhouse agriculture contributing local sources. The flat Dutch polder landscape provides reasonable dispersal, while North Sea westerlies carry relatively clean Atlantic air and greenhouse gas heating contributes localised NOₓ distinctive to this horticultural area.

Today - 21 July | Pollution peaks at 06:00

AQI:

Medium

44.8/100

PM2.5 (fine particles):

Good

9.8/100

PM10 (coarse particles):

Good

3.7/100

NO2 (nitrogen dioxide):

Medium

44.8/100

O3 (ozone):

Fair

25.4/100

SO2 (sulfur dioxide):

Good

2.6/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

1.9/100

PM1 (ultrafine particles):

Good

8.1/100

Levels show the poorest local air quality during the day

Tomorrow - 22 July | Pollution peaks at 05:00

AQI:

Fair

28.9/100

PM2.5 (fine particles):

Good

10.7/100

PM10 (coarse particles):

Good

4.0/100

NO2 (nitrogen dioxide):

Fair

28.9/100

O3 (ozone):

Good

20.0/100

SO2 (sulfur dioxide):

Good

2.7/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

1.6/100

PM1 (ultrafine particles):

Good

7.6/100

Pollen forecast in Alphen aan den Rijn

View pollen forecast

Frequently Asked Questions

Is air quality bad in Alphen aan den Rijn right now?

On 21 July 2026, overall air quality in Alphen aan den Rijn is fair. O3 is the main pollutant at 25.4/100. Pollution peaks around 6:00 AM (NO2: 44.8/100).

Will air quality be worse tomorrow in Alphen aan den Rijn?

On 22 July 2026, air quality conditions in Alphen aan den Rijn will be similar to today, with AQI forecast at fair at 28.9/100. Pollution peaks around 5:00 AM (NO2: 28.9/100).

When is air pollution at its worst in Alphen aan den Rijn?

The main times to watch for Alphen aan den Rijn are the birch, oak, and alder pollen peak over the spring and early-summer period, and hot, still days when local traffic on the N11 and industry emissions build up; onshore winds across the delta typically keep pollutants from settling. Outside of these periods, conditions in Alphen aan den Rijn are typically close to the Dutch national average.

Are air quality levels in Alphen aan den Rijn 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: 21 July 2026 at 16:20 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.

For long term forecasts and maps, see the Airmine app