Analysis of the vertical structure characteristics of Kunming Quasi-Stationary Front based on multi-source observation data

In order to study the vertical structurel characteristics of Kunming Quasi-Stationary Front, according to the Kunming Quasi-Stationary Front heavy precipitation on June 21−24, 2023, using Kunming Quasi-Stationary Front Scientific Test Base (Mile) millimeter-wave cloud radar and microwave radiometer, combined with automatic station and ERA5 reanalysis data, the temperature and humidity structure, reflectivity factor and radial velocity of the new observation data were analyzed. The results showed that: (1) The westward advance of the quasi-stationary front caused the temperature decrease, and the dominant wind direction was the north wind; (2) The integral water vapor and integral cloud liquid water observed by microwave radiometer increased significantly before precipitation, and the occurrence time of real precipitation on the ground lags behind the growth time of integral water vapor, integral cloud liquid water vapor, vapor density profile and liquid water profile of microwave radiometer; (3) The radial velocity and reflectance factor of millimeter-wave cloud radar increased significantly before precipitation, and the echo height and radial velocity decreased before the end of precipitation. Compared with matrix precipitation, continuous precipitation had higher echo top height, thicker clouds and greater particle radial velocity.