Seasonal climate forecasting information can be utilized by water resource managers for planning activities to reduce uncertainty with the additional predictive information. The aim of this study was to determine the predictability of extremely dry and wet conditions by looking into past extreme events and simulating at the basin-scale how well these events can be reconstructed in the Pampanga river basin, Philippines. Three-month seasonal climate forecast (SCF) model ensembles derived from the MIROC-5 Atmosphere Ocean Global Circulation Models (MIROC 5.0 AOGCM) were used to drive the Water and Energy Budget-based Distributed Hydrological Model (WEB-DHM). Extremely dry and wet years in 1982-2000 were integrated into WEB-DHM. Some outputs were incorporated into the crop model ORYZA2000 to quantify crop production on selected ENSO years 1983, 1987, 1991 and 1999-2000 (coinciding with SPAM forecasts). Crop production, drying and flooding trends were well simulated.