In this paper, we extract stable components in extended-range forecasting for the coming 10-30 days by using empirical orthogonal function analysis and some other methods during the snow storm event in November 2009. At the first time, stable components in extended-range forecasting for the coming 10-30 days can be divided into two parts: climatic stable components and abnormal stable components, by contribution rate analysis, similarity coefficient and so on. We combine climatic stable components and low-pass filter components to obtain climatological background field. The results show as follows. 1) The circulation pattern of climatological background field persists for a long time and changes slowly. It provides climatological background for the weather event mainly. 2) The climatological background field can indicate the fluctuations of semi-permanent or permanent center with a large space scales. The climatological background field cooperates well in vertical divisions. 3) The abnormal stable components reflect abnormal circulation, and the circulation pattern of abnormal stable components corresponds to the snow storm event in November 2009 well on the time scale. The climatological background field represents circulation pattern background and the abnormal stable components represent the relative strength of weather system.