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The C3S seasonal forecast products are based on data from several state-of-the-art seasonal prediction systems. Multi-system combinations, as well as predictions from the individual participating systems, are available. The centres currently providing forecasts to C3S are: ECMWF, The Met Office and Météo-France, Deutscher Wetterdienst (DWD), Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC), National Centers for Environmental Prediction (NCEP) and , Japan Meteorological Agency (JMA) and Environment and Climate Change Canada (ECCC), and you can find the details about when each system was introduced in the information contained in the Summary of available data.
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