A weather concerning multivariate regression model combining with factor analysis feedback and tendency analysis feedback is proposed to reduce the counting burden in verifing accuracy of forecasting algorithm. Firstly, the relationship between weather and load indexes are evaluated by factor analysis; Secondly, a tendency analysis about time-varying load indexes is demonstrated; Thirdly, the forecasting equations are presented by multivariate nonlinear regression analysis; Lastly, in forecasting verification process, factor analysis and tendency analysis are applied in the forecasting data, and the error between the feedback of forecasting data and history data are treated as the accuracy verification principle. Numerical examples are given, presenting the accuracy and effectiveness of the proposed method.