The Northeast, Middle-Atlantic, Ohio, and Southeast River Forecast Centers (RFCs) of the NOAA, U.S. National Weather Service (NWS) have recently implemented and tested the "Meteorological Model-based Ensemble Forecast System (MMEFS) in a real-time operational setting. The MMEFS utilizes ensembles of numerical weather prediction (NWP) model outputs, from the National Centers for Environmental Prediction (NCEP) Short-range Ensemble Forecast (SREF) system as inputs to hydrologic models to generate hydrologic forecast ensembles.The hydrologic ensembles quantify hydrologic forecast uncertainty. The uncertainty results from the precipitation and temperature forecasts used to force the hydrologic ensemble.In order to evaluate the performance of the MMEFS for a reasonably large sample of historical forecasts and observations, flow hindcasts were generated for a five year period from the 21-member SREF precipitation and temperature forecasts. The flow hindcasts were verified using the NWS Ensemble Verification System (EVS) for several attributes of forecast quality, including reliability, discrimination, and skill. Results of the verification study are presented and future enhancements of the MMEFS are discussed.