Computational intelligence techniques are becoming popular in hydrologic forecasting. Primarily these are eager learning methods. Lazy (instance-based) learning (IBL) has received relatively little attention, and the present paper explores the applicability of these methods. Their performance is compared with that of neural networks, M5 model trees, regression trees. A flow forecasting problem was solved along with the five benchmark problems. Results showed that one of the IBL methods, the locally weighted regression, especially if used with the Gaussian kernel function, often is more accurate than the eager learning methods.