Abstract: This study aims at revealing the macroscopic structure and microphysical variation mechanisms of the snowfall system in Weining region of western Guizhou Province , exploring the unique advantages of millimeter wave cloud instrument in snow observation , and providing an example for the application of meteorological observation technology in complex mountain climate conditions . Four snowfall events in Weining in winter 2023 were continuously observed by using the millimeter-wave cloud detector and TWP 8-L wind profile radar at Weining Station in Guizhou . Taking the snowfall process from January 21 to 22 , 2024 as a case , this paper analyzes the macro structure and micro-physical changes of the snowfall system preliminarily. By analyzing the radar reflectivity factor , velocity spectrum width , velocity and other parameters at the peak period of snowfall system , we can preliminarily determine whether there are supercooled liquid water droplets within the clouds . The maximum intensity of the snowfall echo indicates the maximum water content in the clouds . When the echo intensity exceeded 20 dBz , its magnitude , duration and height are positively correlated with precipitation on the surface . The speed of pure snowfall stage is 0 to - 2 m/s , the speed of sleet stage is 1 to - 7 m/s , the depolarization ratio of the main snowfall period is - 25 to - 20 dB , and the spectral width is 0 to 2 m/s . The effective radius of snow particles is less than the mixed state of sleet. The application of millimeter wave cloud instrument in snowfall observation and its preliminary analysis results can contribute to a deeper understanding of the macro and microstructure of the snowfall system , and provide some references for the development of cloud mode and the assessment of snow growing potential in weather modification .