Abstract: Based on conventional detection data, wind profile radar data, automatic observation system data and manual observation data, the synoptic situation, formation mechanism and nowcasting for moderate snow and rain on April 12 and 30 in 2021 are analyzed to explore the forecast value of the wind profile radar contour map.The results show that the products of the wind profiler radar can identify the system movement and the change trend of precipitation intensity at least 30 minutes in advance; the vertical velocity v and the refractive index structure C_n²constant can be used to predict the duration of rainfall and snowfall respectively.When the near-ground v range is 5.3 to 6.5 m·s^-1, C_n² range is -123 to -103 dB or C_n² range is -118 to -111 dB, it can be used as a reference index for nowcasting of moderate rain and snow respectively.