Abstract:Based on data from Weihai CINRDA/SA Doppler radar, combined with conventional meteorological data and data from ground automatic meteorological stations, the characteristics of a downburst weather event near Weihai International Airport on 8 September 2018 are analyzed. The results are shown below. 1) The downburst occurs in the northwest airflow background consistent at high and low altitudes, and solar radiation makes the low-altitude atmosphere heated significantly in the afternoon, forming a strong unstable stratification. 2) The trumpet-shaped distribution of vertical temperature and humidity and the temperature lapse rate approaching the dry adiabatic below 850 hPa are favorable environmental conditions for the occurrence of downburst. 3) The presence of ground convergence lines provides dynamic uplifting conditions for the generation of storm cells. 4) From the Doppler radar products, the initial echo of the storm occurred on the clear sky narrow-band echo by the midday sea breeze front, and then the single-cell storm merged and developed into an isolated multi-cell storm; before the downburst, the intensity and height of convective storm echoes developed obviously, convective storm in mature stage was accompanied by echo overhanging structure and three-body scatter characteristics, the downburst quickly reached the ground with the continuous decline of the core of the strong reflectivity factor, and there were obvious convergence and rotation in the middle layer and divergence in the lower layer on the radial velocity map; the gradual decrease of the core of the 60 dBZ reflectivity factor above 5 km and the characteristics of radial velocity (convergence in the middle layer and divergence in the lower layer) can be used to predict the occurrence of downburst three to 9 minutes in advance.