This chapter overviews the modelling approaches used in the European Flood Alert System (EFAS). It explains how they address the challenges of operational early flood forecasting at the European scale. The section on flood forecasting at the European scale covers: i) the principles of calculating flood-warning thresholds; (ii) the techniques used to model river discharge spatially; (iii) the numerical weather predictions (NWPs) meteorological forecasts used as input forcing for the hydrological model; and (iv) a description of a Hydrological Ensemble Prediction System (HEPS). The EFAS has two complementary objectives. The first is complementing member states' activities on flood preparedness, for example by providing national hydrological services with early flood information in addition to their own local, and shorter range forecasting information. The second is providing the European Commission with an overview of ongoing and expected floods in Europe.
- European flood alert system (EFAS)
- Flood-warning thresholds
- Hydrological ensemble prediction systems (HEPS)
- Hydrological model
- LISFLOOD hydrological model
- Numerical weather predictions (NWPs)