EFAS forecasts for the MarchApril 2006 flood in the Czech part of the Elbe River Basin a case study

In spring 2006, the Elbe River Basin was hit by severe snowmelt-driven floods. This article investigates the performance of the European Flood Alert System (EFAS) forecasts for this event in the Czech part of the Elbe River Basin. EFAS runs preoperationally at the European Commission DG Joint Research Centre where it is developed and tested in close collaboration with the National Hydrological Services. The analysis shows that EFAS forecasts were able to detect a signal of probability of flooding up to 810 days in advance. The added value of ensemble forecasts to early flood warning is illustrated.