Abstract: Based on the data of Precipitation and temperature in South China and the reanalysis data of ERA-Inrerim,we analyzed the stations which snow occurrence with the method of rotating EOF,and found that south China can be roughly divided into 4 areas. We selected 4 typical cold and rainy years and less snow years at high temperature of January and filtered the height field. Wefilterde out 2.5 days of synoptic scale transient fluctuation part to study the relationship between the continued South China area of low temperature,rain,snow and weather and synoptic scale transient disturbance. And found that over the Atlantic strong transient eddies in Eurasia to wave the situation to the downstream transmission. In the year of frequent,less intensity of the transient disturbance of strong,and less hair years have more disturbance Boliedong. Wave energy to the east the frequency dispersion for downstream trough and ridge activity provides a steady stream of energy,favorable to the south area baroclinic instability maintain and continue to maintain low temperature,rain,snow and weather.