Highest air pollution Leiden, today and tomorrow
Today (30 June): Air quality in Leiden is fair. AQI and NO2 are fair; PM2.5, PM10, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 11:00 PM (NO2: 21.2/100).
Tomorrow (1 July 2026): Air quality in Leiden is fair. All pollutants stay as today. Pollution peaks around 12:00 AM (NO2: 21.5/100). 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
Leiden's air quality reflects the Dutch coastal zone between Amsterdam and The Hague, with vehicle traffic on the A4 and A44 motorways and the biotechnology research corridor contributing local sources. North Sea westerlies provide maritime ventilation, while the Schiphol Airport flight corridor contributes aviation NOₓ on northerly approaches throughout the year.
Today - 30 June | Pollution peaks at 23:00
AQI:
Fair
21.2/100
PM2.5 (fine particles):
Good
12.0/100
PM10 (coarse particles):
Good
4.1/100
NO2 (nitrogen dioxide):
Fair
21.2/100
O3 (ozone):
Good
17.8/100
SO2 (sulfur dioxide):
Good
2.6/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.8/100
PM1 (ultrafine particles):
Good
11.2/100
Levels show the poorest local air quality during the day
Tomorrow - 1 July | Pollution peaks at 00:00
AQI:
Fair
21.5/100
PM2.5 (fine particles):
Good
14.3/100
PM10 (coarse particles):
Good
4.7/100
NO2 (nitrogen dioxide):
Fair
21.5/100
O3 (ozone):
Good
19.1/100
SO2 (sulfur dioxide):
Good
2.8/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.3/100
PM1 (ultrafine particles):
Good
14.4/100
Pollen forecast in Leiden
View pollen forecastFrequently Asked Questions
Is air quality bad in Leiden right now?
On 30 June 2026, overall air quality in Leiden is fair. AQI is the main air quality indicator at 21.2/100. Pollution peaks around 11:00 PM (NO2: 21.2/100).
Will air quality be worse tomorrow in Leiden?
On 1 July 2026, air quality conditions in Leiden will be similar to today, with AQI forecast at fair at 21.5/100. Pollution peaks around 12:00 AM (NO2: 21.5/100).
Are air quality levels in Leiden 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.
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Data provided by Airmine — Last update: 30 June 2026 at 12:36 CET (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
Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team