Example of the ensemble forecasts (grey lines) taking part in the case study, the deterministic forecasts (thick blue lines), and the observations that were known at the present time (red lines). The ensemble forecasts for water inflows and day-ahead prices have 50 members each. The vertical dashed lines represent the beginning of the time horizon on 2014-04-26 12:00 (local time). For reasons of confidentiality, the forecast values of day-ahead prices are arbitrarily scaled. (a) Water inflows from the six natural tributaries taking part in the upper Rhône river over the time horizon and (b) day-ahead electricity prices over the time horizon.