KNMI Forecast API

Weather forecasts from the Royal Netherlands Meteorological Institute

Location and Time

Location:

Latitude

Longitude

Timezone

Time:

Forecast days

Past days

By default, we provide forecasts for 7 days, but you can access forecasts for up to 16 days. If you're interested in past weather data, you can use the Past Days feature to access archived forecasts.

Hourly Weather Variables

Temperature (2 m)

Relative Humidity (2 m)

Dewpoint (2 m)

Apparent Temperature

Precipitation (rain + snow)

Rain

Snowfall

Weather code

Sealevel Pressure

Surface Pressure

Cloud cover Total

Cloud cover Low

Cloud cover Mid

Cloud cover High

Visibility

Reference Evapotranspiration (ET₀)

Vapour Pressure Deficit

Wind Speed (10 m)

Wind Speed (50 m)

Wind Speed (100 m)

Wind Speed (200 m)

Wind Speed (300 m)

Wind Direction (10 m)

Wind Direction (50 m)

Wind Direction (100 m)

Wind Direction (200 m)

Wind Direction (300 m)

Wind Gusts (10 m)

Surface Temperature

Temperature (5 m)

Temperature (100 m)

Temperature (200 m)

Temperature (300 m)

Daily Weather Variables

Weather code

Maximum Temperature (2 m)

Minimum Temperature (2 m)

Maximum Apparent Temperature (2 m)

Minimum Apparent Temperature (2 m)

Sunrise

Sunset

Daylight Duration

Sunshine Duration

UV Index

UV Index Clear Sky

Precipitation Sum

Rain Sum

Showers Sum

Snowfall Sum

Precipitation Hours

Maximum Wind Speed (10 m)

Maximum Wind Gusts (10 m)

Dominant Wind Direction (10 m)

Shortwave Radiation Sum

Reference Evapotranspiration (ET₀)

Settings

Temperature Unit

Wind Speed Unit

Precipitation Unit

Timeformat

Usage license:

Only for non-commercial use and less than 10.000 daily API calls. See Terms for more details.

API Response

Preview:

Download XLSX Download CSV

API URL (Open in new tab or copy this URL into your application)

Data Sources

KNMI provides weather forecasts from the HARMONIE AROME model with ECMWF IFS initialization. This is a collaboration of multiple European national weather services under the name "United Weather Centres-West" (UWC-West). Two model configuration one for Europe (5.5 km resolution) and an inset for the Netherlands (2 km resolution) are available. All data is updated hourly and provides forecast for up to 2.5 days. After 2.5 days, Open-Meteo combines forecasts with the ECMWF IFS 0.25° model to provide up to 10 days of forecast.

Weather Model	Region	Spatial Resolution	Temporal Resolution	Forecast Length	Update frequency
KNMI HARMONIE AROME Netherlands	Netherlands, Belgium	2 km	1-hourly	2.5 days	Every hour
KNMI HARMONIE AROME Europe	Central & Northern Europe up to Iceland	5.5 km	1-hourly	2.5 days	Every hour

KNMI HARMONIE AROME model area Europe (blue/red) and Netherlands nest (green). Source: KMNI Blog.

API Documentation

For a detailed list of all available weather variables please refer to the general Weather Forecast API. Only notable remarks are listed below

Solar Radiation: KNMI supplies only global solar radiation data and does not offer direct or diffuse solar radiation. Open-Meteo applies the separation model from Razo, Müller Witwer to calculate direct radiation from shortwave solar radiation.
Wind Direction Correction: Wind direction has been calculated from U/V wind component vectors. Special care has been taken to correct for the Rotated Lat Long projection. Without this correction, wind directions have an error of up to 15°.
Wind on 50, 100, 200, 300m: Wind forecasts for higher altitudes are only available for the Netherlands area.
Pressure Level Data: Forecasts on pressure level are only available for the European model.

KNMI Forecast API

Location and Time

Hourly Weather Variables

Additional Variables And Options

Solar Radiation Variables

Pressure Level Variables

Weather models

Daily Weather Variables

Settings

API Response

Data Sources

API Documentation