【摘要】 利用Micaps资料、闪电定位数据以及NECP/FNL 1°×1°再分析资料,对江门市的一次强雷电过程闪电分布特征、环流形势和物理量场进行统计和诊断分析,结果表明:该次强雷电过程闪电强度集中在10～60 kA,强雷电过程发生在西太平洋副热带高压强盛的背景下,洋面上暖湿气流向沿海地区汇聚,风随高度逆转,形成中层干冷、低层暖湿的不稳定层,500 hPa相对湿度场、850 hPa比湿、水汽通量散度以及假相当位温等物理量的变化对强雷暴的发生有指示作用,更有利于强闪电的发生。更多还原

【Abstract】 Using the Micaps and lightning location data and NCEP/FNL 1°×1° reanalysis, this paper performs a statistical study and diagnostic analysis of the lightning distribution, circulation patterns and physical quantities fields for a severe thunderstorm that happened in the city of Jiangmen. The result is shown as follows. During this process, the lightning intensity is mainly around 10～60 kA. Against the background of a dominating subtropical high in the western Pacific, this severe lightning happened when warm and humid air stream over the ocean accumulated towards the coastal area and the wind turned reversely with height to form an unstable layer that was both dry and cold in the middle but warm and humid at the bottom. As indicators of severe thunderstorm, the variations of such physical quantities as 500-hPa relative humidity, 850-hPa specific humidity, water moisture flux divergence and pseudo-equivalent potential temperature make severe lightning more likely to happen.更多还原