Med range forecast section of Central Meteorological Observatory will use new climatological normals of the period 1971-2000 from on January 1st, 2003 according to the requests by WMO. The results of normals change show the dekad precipitation of South China increases very obviously in summer (from June to August) and the dekad mean temperature of most observation stations ascends in winter (from October to April). The change of dekad mean temperature results in the abnormals descent and influences the confirmation of cold air processes.