In this study,using the daily precipitation data collected at 63 conventional meteorological observatories in Zhejiang Province from 1973 to 2017 and the sea surface temperature field,wind field,height field,humidity field and outgoing long-wave radiation (OLR) field provided by NCEP/NCAR,the EOF,anomalies Synthetic and t-test methods are used to analyze the time and space distribution of total rainy days in February to April in Zhejiang Province,as well as the atmospheric circulation field,previous sea surface temperature,and the distribution characteristics of the same OLR field in continuous rainy weather.Based on the analysis,we then explore the causes.The results show that the spatial distribution of the total number of rainy days in Zhejiang Province from February to April is generally divided into two categories:in the first,the distribution is the same around the province,while in the second the distribution is different between the north and south.When the high ridge of the Ural Mountains is strong (weak),the Okhotsk sea trough in the middle and high latitudes of the Eurasian continent and western Pacific subtropical high are also strong (weak),which causes the consistently strong (low)density rain in the province.OLR is a negative anomaly area in Zhejiang Province,which is prone to the same pattern of continuous rainy weather in the province.When the OLR is a positive anomaly area in Zhejiang Province,it is prone to cause the weather of consistently less rain than average in the province.In addition,when the weather of continuously more rain appears in the province,then the SST of the Equatorial Middle East Pacific in the early period and same period are significantly higher;otherwise,the SST of the Equatorial Middle East Pacific in the early period and same period are significantly lower.The SST in the western equatorial Pacific is the anti-phase.In the following year of El Niño,the weather phenomenon of continuously more rain typically appears in the province.In the following year of La Nina,the weather phenomenon of continuously less rain usually appears.