About
Applications that want to benefit from SMHI Open Data Radar can use this service to retrieve data.
The Entry point is located at https://opendata-download-radar.smhi.se/api.
The data is returned as mediatype application/json (JSON). All times are in UTC (Coordinated Universal Time) unless you explicitely choose another timezone.
The end result of a query is a GeoTiff or PNG file representation of the data obtained by the radar array that SMHI maintains. There are also links to zip-files containing all the GeoTiff or PNG files for the queried day. To get started with the API, see Examples and the Demo.
Temporal extent
To check the temporal extent of the available images and the latest update of the images, poll
https://opendata-download-radar.smhi.se/api/version/latest/area/sweden/product/comp
(with correct version, area and product). In the answer you get the updated time, which is the time when the latest radar images where added to
the service. The answer also contains listings for the firstFiles and lastFiles available for a certain area and product.
The result contains a valid tag which represents the time the original radar data is obtained.
Usually, new radar images are added every five minutes.
GET /api/version/{version}/area/{area}/product/{product}
| Version | When the API for a given area and product is changed, the version is increased. Old versions will be available for a limited time. |
| Area | There is only one area available for the API, sweden. |
| Product | Right now we only have one product available for the API, comp which is a composite of the data obtained from the radar beacons. |
There are two optional query parameters that can be used:
GET /api/version/latest/area/sweden/product/comp?format={format}&timeZone={timezone}
| Format | The possible formats are tif and png. Choosing for example tif results in an answer containing only links to the geotiff images. |
| TimeZone | The default time zone is UTC. But you can use most time zones generally supported. Some examples: CET, PST and EST. |
Data
You can find more information about the data in the radar images here.
Data structure
The data is structured according to the following:
GET /api/version/latest/area/sweden/product/comp
This is the entry point level. It contains links to the available years.
GET /api/version/latest/area/sweden/product/comp/{year}
This is the year level. It contains links to the available months.
GET /api/version/latest/area/sweden/product/comp/{year}/{month}
This is the monthb> level. It contains links to the available days.
GET /api/version/latest/area/sweden/product/comp/{year}/{month}/{day}
This is the day level. It contains links to the actual data. Two images every five minutes, one png and one geotiff image.
The query parameters described above can be used at every level.
Examples
GET /api/version/latest/area/sweden/product/comp
...
GET /api/version/latest/area/sweden/product/comp/2015/05/26
...
GET /api/version/latest/area/sweden/product/comp/2015/05/26?format=tif&timeZone=GMT
...
Demo
The API we describe here is currently being used by us at the following site:https://opendata-download-radar.smhi.se/explore. This site visualizes the images as a continuous stream. You can also download a complete day of radar images, both in geotiff and png format. The site is a pure front-end application so you can access the source code and get inspiration.
Reference System
The data of the downloaded image files uses SWEREF99TM, EPSG:3006. Use this reference system to geoposition the image files correctly.
See https://epsg.io/3006 for more information about the reference system and corresponding configurations. The GeoTiff files can be viewed in QGIS (for example), the header metadata contains the necessery reference system information to geoposition it correctly.
Licence
SMHI Open Data API is published under these Terms and conditions.
Contact
Questions or inquiries can be sent to: opendata-support@smhi.se.