Instantaneous weather observations are at first available since 2010. Daily and monthly weather observations are mainly available from the 1960's, depending on the observation station. Sea and air quality observations have their own time limitations. The begin dates of data depends on technical limitations. Older data is gradually added as technical and quality limitations are resolved.
Using this service is free and there is no registration.
The service includes the most commonly asked parameters. In order to keep the service simple and easy to use, the more rare datasets with differing formats are not included at least for now.
The code used for the service will be added to GitHub.
The download observations - service is built over the open data interface. The interface itself is originally intended for machine readable data and is only available in Finnish and English. Since the download service uses the interface, the same language restrictions apply and Swedish is at least for now not supported.