Data sources and licences

Wind gusts at 10-minute, hourly and daily cadence; precipitation at 10-minute, hourly and daily cadence; hourly present-weather observations and daily observed phenomena including hail. Published at opendata.dwd.de and reused here under CC BY 4.0.

The archive is published in two tiers, and the difference matters for a document: the historical archive is frozen and its quality control is complete, while the rolling recent archive covers roughly the last 500 days and is published before quality control finishes, so those values can still change. Every record states which tier each figure came from.

Attribution as required: Quelle: Deutscher Wetterdienst. Datenbasis: Deutscher Wetterdienst, Werte nach Ort und Zeitraum ausgewählt und in km/h umgerechnet.

German postal places and the districts that own them, used to resolve a postal code when an address cannot be matched, and to name the district a record is about. Licensed CC BY 4.0.

Address geocoding, via the Nominatim service. © OpenStreetMap contributors, ODbL. The precision the geocoder achieved is printed in every record, because a house number and a postal-code centre are not the same claim.

Lightning. There is no lightning network in Europe whose data can be licensed for this at a price that fits a €19 record, and the community networks that publish freely forbid exactly this use in their own terms. So lightning is not reported at all.

Radar-derived hail for past dates. The open radar archive of reflectivity and hail classification is kept for 48 hours. It cannot be reconstructed afterwards, and the deep gridded archives hold rainfall in millimetres, which says nothing about hail. Records therefore state hail only where a station observed it.