This paper presents a model for forecasting daily changes of water lev
el in Lake Kinneret during flood periods. The model is based on the wa
ter budget equation. its parameters are calibrated by multiple regress
ion using inflow, outflow and rainfall for the preceding day. A correc
tion factor which takes into account the errors of forecasts for the p
receding two days is added to the model. Split-sample calibrations and
applications yield results which are accurate to within 10 to 20 mm.