Abstract:Based on the NCEP (National Center of Environmental Prediction) reanalysis data with a resolution of 1°×1°, conventional meteorological data and intensive snowfall observations from 2008 to 2018, ten typical weather processes of rainsnow conversion in Hangzhou are selected in the aspects of largescale circulation background and physical quantities such as dynamic, water vapor and thermal factors. Ultimately, the typical winter forecast hints of rainsnow conversion in Hangzhou are concluded as follows: (1) The largescale circulation configuration provides favorable conditions including water vapor, dynamic lifting and inversion or isothermal stratification in the middle and lower troposphere for the formation of rain to snow. 〖JP2〗(2) The physical quantities such as water vapor 〖JP3〗and dynamic factors should satisfy specific conditions for snow. (3) The temperature stratification in Hangzhou should be 〖WTBX〗T〖WTBZ〗2m≤1.5 ℃,〖JP〗 〖WTBX〗T〖WTBZ〗925≤4.0 ℃, 〖WTBX〗T〖WTBZ〗850≤0 ℃, 〖WTBX〗T〖WTBZ〗700≤-1.0 ℃ and 〖WTBX〗T〖WTBZ〗500≤-10.0 ℃. In addition, the possible conditions for heavy snow or even blizzards in Hangzhou are further discussed. Moreover, two typical precipitation processes at the beginning of 2019 are selected for forecast inspection.