Impact of improved soil moisture on the ECMWF precipitation forecast in West Africa

[1] West Africa is a region of strong coupling between soil moisture and precipitation and where numerical weather prediction of precipitation generally exhibits poor skill. This region has been the focus of the African Monsoon Multidisciplinary Analysis - Land-surface Model Intercomparison Project in which the European Medium-Range Weather Forecasts (ECMWF) land surface scheme—among others—has been driven offline by accurate meteorological forcing in order to produce improved soil moisture estimates. The impact of these improved initial conditions for soil moisture on the short-range precipitation forecast is examined with the ECMWF Integrated Forecast System. While direct and beneficial impact of a more realistic soil moisture is obtained for accumulated precipitation in the regions over the coast of the Gulf of Guinea and eastern Sahel, over the rest of the Sahel the impact is detrimental or neutral.