Abstract:Based on surface observations, lightning location data, Doppler radar data, and ECMWF ERA5 reanalysis data, the characteristics of cloud-to-ground (CG) lightning activity of the sea-effect snowfall with CG lightning in Shandong Peninsula from November to the following February during 2017-2023 are studied. The results are as follows. The CG lightning mainly occurs in the sea-effect snowfall over the Bohai Sea from November to the following January, with the highest frequency in November and gradually decreasing frequency from December to the following January, and there is no CG observed in February. The diurnal variation of CG lightning shows a multi-peak structure, primarily from wee hours to morning. The frequency and distribution range of CG lightning in sea-effect snowfall of sleet type are greater than those of pure snow type. 90% of the thunderstorm days with pure snow type sea-effect snowfall have CG lightning less than 10 times. CG lightning during the two types of sea-effect snowfall is distributed both over the Bohai Sea and on land, and the distribution on land is connected to the terrain. CG lightning of sleet type is mainly distributed over the Bohai Sea, whereas CG lightning of pure snow type is mainly distributed on land, generally near areas of heavy snow, and in the northwest direction of the center of heavy snow (upwind direction). The convective development height of the sleet type CG lightning is higher than that of pure snow type. The occurrence time and location of CG lightning have a certain indicative effect on short-time imminent warning of snowfall period and location of heavy sea-effect snowfall, and the snowfall intensity increases significantly within 0-2 h after the occurrence of CG lightning in sea-effect snowfall. At the heavy snowfall centers near CG lightning locations, snowfall intensity may reach the level of blizzards.