ECMWF: le migliori previsdioni al mondo, un orgoglio europeo

The European Centre for Medium-Range Weather Forecasts (ECMWF, Reading, UK) represents the best source of daily forecasts at global level. This paper provides an overview of the Centre: forty-year-history, mission and international success. With an annual budget of about 55 millions £, ECMWF continually improves its supercomputers operating speed (up to 200 Teraflops) and modelling techniques to predict future weather (up to about 2 weeks ahead, but extended forecasts are also produced for monthly and seasonal timescales). Few case studies underline the key role of technology and scientific knowledge behind weather forecast, although often their contents are taken for granted. Finally, the analysis outlines some perspectives for the future of meteorological forecasts and related studies (increasing global models spatial resolution from 9 to 1-2 km in the next future).