With SVD (singular value decomposition) enough the time coefficients of predicted fields and factor fields are cut so that their relationships represent ones between two fields and estimate of linear combination of the time coefficients and the vector of predicted fields indicate the original. With optimization technique the whole field is predicted with estimating the time coefficients of predicted field according to the coefficients of factor fields and linear combination of the coefficients and the vectors of predicted field. Predictable large scales are analyzed mainly and unpredictable disturbance are canceled. Large-scale changes of predicted fields are predicted with chief coupled relationships between two fields. Forecast of the precipitation fields during the summer 1998 have been simulated and large areas of singular climates were predicted exactly.