The gains by the scientific community in the forecasting of severe weather events and floods over the last decade has allowed the development of a new generation of flood warning systems which can provide reliable estimations of the discharge hydrograph with short-term (1–2 days) and mid-term (3–5 days) lead times. In the framework of the 2007 MAP D-PHASE project, such systems were first tested in real time. During this operational benchmarking, it was possible to force hydrological models with data from ensemble numerical weather prediction systems. An additional innovation in the nowcasting of flood events is the adoption of new quantitative estimations of precipitation from radar systems.
Such efforts are necessary in order to improve the communication of uncertainty between the modellers and the warning agencies and between the warning agencies and the task forces who are responsible for flood mitigation. More than 30 Swiss end-users are participating in MAP D-PHASE. Their feedback will be evaluated in order to further investigate extreme flood events and in order to finalize the practical application of these new tools for operational flood forecasting.
The advantages and drawbacks of such new forecasting systems are presented here.