Abstract: Based on the ERA5 reanalysis data of European Centre for Medium-Range Weather Forecasts (ECMWF), the NCEP reanalysis data, the satellite and radar data of Panzhihua, and the MICAPS routine meteorological data, the synoptic method was used to comprehensively analyze the cold advection forcing thunderstorm weather process in Panzhihua, Sichuan provinc on April 13, 2020. This thunderstorm process was a mixture of hail, short-term heavy rainfall and thunderstorm strong wind, and its main influence systems included the upper-level jet at 200 hPa, the plateau trough at 500 hPa, the shear line and the southwest jet at 700 hPa, and ground convergence line. The northwest dry and cold air at 200~500 hPa travelled southward along the plateau trough to play a leading role in this process. The weak southwest jet at 700 hPa transported a certain amount of water vapor and unstable energy to the local area, and the middle and low-level shear lines and the ground convergence line promoted the convergence and uplift of the warm and humid airflow. In addition, atmospheric structure of “upper cold and lower warm”, the strong vertical wind shear in the middle and lower layers, the convergence of the low-level and divergence of the upper-level, appropriate 0 °C and −20 °C layer heights, the strong CAPE and K index, and the large vertical temperature decline rate between 700 hPa and 500 hPa were all key factors for the occurrence and development of this thunderstorm weather process.