Hillslope hydrology models for forecasting in ungauged watersheds

In the context of hydrological forecasting from ungauged catchments there are conflicting requirements with respect to minimizing data inputs (which restricts physically based modeling of hillslope runoff processes) and simultaneously developing a soundly based, portable operational model. This paper shows that empirical preprocessing of data and the inclusion of selected physically based model elements within an essentially empirical model provide a sound operational approach. Selected examples of the model performance are presented in application to catchments in Texas and Arkansas.