Hydrological seasonal forecast over France: feasibility and prospects

This article presents a first evaluation of a hydrological forecasting suite at seasonal time scales over France. The hydrometeorological model SAFRAN‐ISBA‐MODCOU is forced by seasonal forecasts from the DEMETER project for the March–April–May period. Despite a simple downscaling method, the atmospheric forcings are reasonably well represented at the finest scale. The computed soil moisture shows some predictability with large regions of correlation above 0.3. Probabilistic scores for soil moisture and river flows for four different catchments are higher than that for atmospheric variables. These results suggest to go further for building an operational hydrological seasonal forecast system.