Seasonal forecasts of weather provide valuable information for reservoir operations, particularly during unusual events, such as floods or droughts. A challenge confronting reservoir operators today is whether to incorporate new climate products into their operations to help manage such extremes or to use historic data to guide them. This research evaluates the accuracy and value of the Hydrologic Ensemble Forecast System (HEFS) generated from the Climate Forecast System version 2 (CFSv2) using the operations of the Salt Lake City Parley’s System nd compares it to the accuracy and value of using an Ensemble Streamflow Predictions (ESP) approach. Streamflow reforecasts are generated and used to evaluate the predictive skill of the HEFS in reservoir management. Using the HEFS may offer more insight when responding to climate driven extremes than the ESP approach because the HEFS incorporates a fully coupled climate model into its forecasts rather than relying on the historic record.