This method uses different slots and sets different slots if the Compute Forecast Period Incremental Local Inflows is selected. But, there is always a Source slot and a Target slot where the Source slot is input and used to forecasted and set the Target slot. If the Compute Forecast Period Incremental Local Inflows is selected, the computational subbasin calls this method and uses the Cumulative Local Inflow (Source) to forecast and set the Forecasted Cumulative Local Inflow (Target). If it is not selected, the reservoir calls this method at the beginning of the timestep and uses the Deterministic Incremental Local Inflow (Source) slot to forecast and set the Local Inflow slot (Target). The following uses the Source/Target terminology to describe the methods.

The Source slot values are required inputs for each timestep. At the beginning of each controller timestep, the Geometric Recession method is executed. For each forecast timestep within the period of perfect knowledge, the Target is set to the Source value. For each forecast timestep after the period of perfect knowledge, the Target is set by multiplying the value of the Target from the previous timestep by the constant recession factor.

A value for the Source slot must be known at every timestep during the run. If Target values are desired past the end of the run, there must also be values in the Source slot at timesteps past the end of the run. If values for Source slot are not entered past the end of the run, the Target values for these timesteps are assumed to be zero.

This method uses different slots and sets different slots if the Compute Forecast Period Incremental Local Inflows is selected. But, there is always a Source slot and a Target slot where the Source slot is input and used to forecasted and set the Target slot. If the Compute Forecast Period Incremental Local Inflows is selected, the computational subbasin calls this method and uses the Cumulative Local Inflow (Source) to forecast and set the Forecasted Cumulative Local Inflow (Target). If it is not selected, the reservoir calls this method at the beginning of the timestep and uses the Deterministic Incremental Local Inflow (Source) slot to forecast and set the Local Inflow slot (Target). The following uses the Source/Target terminology to describe the methods.

The Source slot values are input for each timestep. At the beginning of each controller timestep, the Exponential Recession method is executed. For each forecast timestep within the period of perfect knowledge, the Target is set to the Source value. For each forecast timestep after the period of perfect knowledge, the Target slot is set as described below.

If the Source at the end of the period of perfect knowledge is negative, the Target at that timestep is exactly equal to the Source. However, the Source used in the recession equation, is the last positive value for Source. In the event that there is not a positive value for the Source, RiverWare issues a warning, and all values for Local Inflow within the forecast period will be set to the Minimum Forecasted Flow.

A value for the Source slot must be known at every timestep during the run. If the Target values are desired past the end of the run, there must also be values in the Source slot at timesteps past the end of the run. If values for Source are not entered past the end of the run, the Target values for these timesteps are assumed to be zero.