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Based on conventional observation data, encrypted data from automatic stations, radiosonde data, ERA5 reanalysis data, and Doppler weather radar data, a severe convective weather process affecting the coast of northern Zhejiang on April 30, 2021, is analyzed. The results show that: (1) This process occurred in the background of the highaltitude cold vortex and the strong northwest jet behind its trough. The lowaltitude shear line and the surface convergence line jointly provided the triggering conditions for uplift. (2) Appropriate CIN, relatively low LFC, and high CAPE were conducive to the formation of unstable stratification with cold upper and warm lower layers. Deep vertical wind shear combined with dry air entrainment in the middle layer further enabled the occurrence, maintenance, and development of severe convective weather. (3) The development of this gust front had gone through three stages. When the thunderstorm’s main body generated a gust front that developed strongly and caused strong winds on the ground, there were characteristics such as a rapid drop in the height of the strong echo centre, a strong inflow in the rear middle layer, a radial velocity divergence field, and velocity ambiguity. (4) The sinking of a strong cold air pile formed a dense area of pressure gradient and wind temperature and humidity shear, which could easily lead to thunderstorms and gale weather. The negative and positive temperature variation centres had certain indications for strong convection. (5) During the transit of gust fronts, there was often an abrupt increase in atmospheric pressure and wind speed, sudden change in wind direction, and sudden drop in temperature. Due to the limitations of radar observation distance, forecasters needed to analyze the potential in the early stage and jointly studied and judged the automatic station elements and radar information.