Based on data from 714 national and regional weather observation stations, lightning observations, ERA5 reanalysis, and typhoon tracks from 2017 to 2021, this study analyzed 1) the spatiotemporal distributions of thunderstorm gale in Shaoxing and surrounding areas, 2) circulation characteristics of the different weather types of thunderstorm gale in the southern mountainous regions, and 3) investigated the role of terrain in three thunderstorm gale events using convection parameters by the EAR5 data. The results as follows: (1) The spatial distribution of the annual average frequency of thunderstorm gale shows two obvious high incidence areas near the southern mountainous terrain in Shaoxing, namely the westside of the Kuaiji Mountains and the southwest side of the Siming Mountains. (2) Thunderstorms gale in the southern mountainous areas of Shaoxing mainly occur from the afternoon to the early half of the night with significant daily peak variation from March to September. It also often appears in morning and the late half of the night, rarely occurs in the plain areas in morning and the late half of the night. (3) There are three typical weather types for thunderstorms gale in the southern mountainous areas of Shaoxing with different forcing: a) cold advection, b) warm advection, and c) quasi-barotropic. Among them, the quasi-barotropic category is the most common (66.3%), in which the subtropical high pressure plays a significant role. (4) There are two formation mechanisms of thunderstorm gale in the southern mountains: First, mountain terrain leads to the airflow uplift and strengthen the upward movement; Second, the existence of mountain reduces the height difference between the free convection height and the underlying surface with increasing altitude, making convection more likely to occur. However, thermal effects mainly occur in the afternoon
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