The European flood alert system EFAS

The European Flood Alert System (EFAS) prototype is running pre-operationally for the whole Europe and is already providing 3-10 day hydrological EFAS forecasts for 22 hydrological national services (covering most of the transnational river basins in Europe) that have signed a Memorandum of Understanding. EFAS features deterministic as well as probabilistic hydro-meteorological forecasts. Deterministic hydrological EFAS forecasts are based on DWD (7 day lead-time) and ECMWF (10 day lead-time) deterministic meteorological forecasts, while EFAS hydrological ensemble forecasts are based on the 51 meteorological member EPS forecasts (10 day lead-time) provided by ECMWF. The EFAS system setup and data flows are explained. Furthermore, the way how complex EFAS forecast information is communicated in an efficient way to the end users is presented.