Abstract: Based on the early summer precipitation data from 31 meteorological stations in the Songhua River Basin and the NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research) reanalysis data from 1961 to 2017,the temporal and spatial distribution of precipitation in the Songhua River Basin and the influence characteristics of circulation were discussed by statistical methods.Results show that there are mainly three modes of the precipitation in the Songhua River Basin:the consistent rainfall mode in the whole basin,the anti-phase rainfall modes from northwest to southeast and from northeast to southwest.The main circulation characteristics affecting the three distribution modes are the low pressure at the east of Lake Baikal and Okhotsk blocking high (southwest low-northeast high),Ural ridge-West Siberian trough-Stanovoy Range ridge (a two-ridges-and-one-trough type),and the Bohai Sea and North China low pressure and the high in the northeast.The local high pressure or blocking situation plays a very important role in the formation of the three modes of precipitation in the early summer over the Songhua River Basin.The East Asia-Pacific and Polar-Eurasian types are teleconnections that play an important role in the distribution of the first mode precipitation.

Key words: Songhua River basin, Early summer precipitation, Circulation characteristics