About WZ Diagrams

What is WZ Diagrams?

WZ Diagrams is a professional weather forecast visualization application for meteorology enthusiasts, outdoor professionals, and anyone who wants more than a simple weather icon. Instead of a single daily summary, the app presents full forecast time series as interactive diagrams (meteograms): temperature and dew point, precipitation amount and probability, wind speed, gusts and direction, cloud cover by altitude layer, and 850 hPa temperature.

The app is available as a Progressive Web App that runs directly in your browser, and as a native app for iOS and Android.

Forecast Models

WZ Diagrams gives you direct access to the raw output of the world's leading numerical weather prediction models, including:

  • ECMWF IFS (deterministic and ensemble) and ECMWF AIFS, ECMWF's AI-based forecasting system
  • ICON (DWD, Germany), GFS (NOAA, USA), GEM (Environment Canada)
  • UKMO (UK Met Office), Météo-France, DMI (Denmark), JMA (Japan), CMA GRAPES (China)

Ensemble models run the same forecast many times with slightly perturbed starting conditions. The app visualizes the P10–P90 spread of all members, so you can judge forecast uncertainty at a glance — wide spread means low confidence.

Interactive Widgets

Beyond the forecast diagrams, the app includes a set of interactive map widgets:

  • Live precipitation radar with animation and opacity control
  • Lightning map showing recent strikes detected by the EUMETSAT Meteosat-12 Lightning Imager
  • Topographic map with all your favorite stations
  • Climate map showing the color-coded Köppen-Geiger climate classification of any location, with the climate normals (1991–2020) for context

Data Sources

We believe in transparent data provenance. WZ Diagrams is built on open data:

  • Forecast data is provided by the Open-Meteo APIs, which redistribute the open-data output of national weather services (ECMWF, DWD, NOAA, Met Office, Météo-France, DMI, JMA, CMA, Environment Canada).
  • The Köppen-Geiger climate classification is based on Beck et al. (2023), Scientific Data 10, 724 (CC BY 4.0), 1991–2020, approximately 1 km resolution.
  • Lightning data originates from the EUMETSAT Meteosat Third Generation Lightning Imager and contains modified EUMETSAT data.
  • Base maps: © OpenStreetMap contributors, © CARTO.

Who Runs This Site?

WZ Diagrams is developed and operated by Wetterzentrale, an independent weather enthusiast project from Germany. The app is free to use; the web version is financed through a small banner advertisement, and an optional Pro subscription removes ads and enables cross-device sync of your favorites and settings.

Questions, feedback, or data requests: support@wetterzentrale.de