EDR API: New 10-minute-in-situ-meteorological-observations collection
KNMI collects meteorological surface observations from automatic weather stations (in-situ) situated in the Netherlands and BES islands. This data is distributed via the Open Data API and via an Open Geo Consortium (OGC) Environmental Data Retrieval (EDR) API.
In this news item we give you the highlights of what is new in the `10-minute-in-situ-meteorological-observations` collection in our EDR API. This new collection replaces the existing `observations` collection.
The EDR API allows users to query datasets on specific parameters in a spatio-temporal manner, reducing the need to download entire datasets. For more information on this, see our EDR API documentation.
Improvements in variables
The new `10-minute-in-situ-meteorological-observations` collection now closely matches the corresponding filed-based Open Data API dataset. This means that all variables (parameters) are now matching in name, metadata and data. It also means that all variable names have changed compared to the old `observations` collection.
Further improvements include new parameter description fields in the parameter metadata (description, duration, aggregation-method and level) and improvement of parameter metadata according to CF conventions and QUDT ontology.
Because of the improvements in the parameter metadata, there are now more query options. It is now possible to filter parameters on their CF standard name, level, aggregation method or duration.
For an overview of the included variables, see the Technical Documentation. For an overview of the filtering options, see the Swagger Specification.
Improvements in functionality
We have added two methods to query multiple stations. It is now possible to query on a WKT polygon using the `/area` endpoint. Additionally, it is possible to query multiple distinct stations using the `/locations/{locationId},{locationId}` method. Previously, responses returned a Coverage for a single station and a CoverageCollection for multiple stations. Now, all responses are returned as a CoverageCollection for consistency.
We are now consistently using the WIGOS Station Identifier (WSI) in all our responses and query parameters. The old WMO-IDs are still visible in the output of the `/locations` endpoint. The WSI is now included in the CoverageJSON output as `eumetnet:locationId`.
We have removed the third position element (station elevation, or z-coordinate) from the GeoJSON output of the `/locations` endpoint. Previously, the z-coordinate in the `observations ` collection was a value measured in meters elevation above mean sea level, while GeoJSON mandates this value to be the elevation in meters above the WGS84 ellipsoid. The elevation is now reported separately in the properties of the GeoJSON.
Changes and improvements in data availability
The new collection includes historic observations from 2012-01-01 onwards. This is later than the `observations`, which had historic observations from 2003 onwards. However, due to the way the data was collected before 2012, we could not guarantee the validity of this time period and has therefore been removed from the collection.
Like the file-based Open Data API dataset, the new collection can be updated with missing data up to 7 days later. We recommend the use of the MQTT Notification Service to be notified of updates of earlier timepoints.
Deprecation previous `observations` collection
Because of the release of the new 10-minute-in-situ-meteorological-observation collection, we have deprecated the previous `observations` collection. This means that as of 01-07-2025 the old collection has been deprecated. Per 29-09-2025 the dataset will no longer receive any updates.
The deprecation of the `observations` collection corresponds with the deprecation of the `Actuele10mindataKNMIstations` dataset.
More information
For more comprehensive and technical documentation about stations, variables, timestamps and availability, please refer to the new 10-minute-in-situ-meteorological-observations documentation page.