Evaluation of precipitation forecasts for five-day streamflow forecasting in Narmada River basin

The accuracy of quantitative rainfall forecast (QPF) obtained from a Numerical Weather Prediction (NWP) model plays a crucial role in setting up a streamflow forecasting system for a catchment. Additionally, a suitable hydrological model is required. This study addresses input and model uncertainty in developing a five-day streamflow forecasting system in Narmada River Basin. We use deterministic and ensemble QPF(s) obtained from Japan Metrological Agency (JMA), National Center for Medium-Range Weather Forecasting (NCMRWF), and European Center for Medium-Range Forecast (ECMWF). We use two hydrological models, Soil and Water Assessment Tool (SWAT) and Variable Infiltration Capacity (VIC), to generate streamflow forecasts. By comparing simulated streamflow forecast(s) with the observed discharge data, our results indicate that the forecast accuracy of NCMRWF is better than other forecasting products for lead times of 2 to 5 days. The streamflow generated using VIC produces better results than that obtained from the SWAT hydrological model.