基于混合长基线贵州天电阵列的一次强对流天气过程分析

Analysis of a Severe Convective Weather Process Based on the Hybrid Long-Baseline Guizhou Lightning Detection Array

摘要: 利用ERA5再分析资料、贵阳龙洞堡机场C波段双偏振天气雷达资料雷达数据和基于混合基线技术的闪电探测定位系统构成的贵州天电阵列闪电定位数据，对2025年2月14日贵州省一次高架雷暴天气过程进行分析。结果表明：此次对流天气主要受高空槽以及低空急流、地面准静止锋的影响。850百帕至地面形成冷垫，700百帕暖湿气流沿着冷垫爬升，在空中激发对流，出现高架雷暴。闪电分布与对流天气移动方向基本一致，在贵州省西南部闪电活动活跃，分布密集，最大密度达到28次/0.1˚ × 0.1˚；闪电密集区域与降水量最大值区域对应，闪电极性以负闪电为主，负闪电比例达到62%。在贵阳市出现雷雨时段的三个雷达图和闪电极性分布图上看出，冬季对流降水强度较弱，最大组合反射率值为55 dBz，对流分布松散，且移动迅速。闪电分布在回波移动前方，可借助雷电监测预警系统，对高架雷暴天气的发展阶段和方向进行判断，并迅速决策、提前发布预警信息。

Abstract: This study analyzes an elevated thunderstorm event that occurred in Guizhou Province on February 14, 2025, utilizing ERA5 reanalysis data, C-band dual-polarization weather radar data from Guiyang Longdongbao Airport, and lightning location data from the Guizhou Lightning Detection Array, which is based on hybrid baseline technology. The results indicate that this convective weather event was primarily influenced by an upper-level trough, low-level jet streams, and a surface quasi-stationary front. A cold layer formed between 850 hPa and the surface, while warm and moist air at 700 hPa ascended along this cold layer, triggering convection aloft and resulting in an elevated thunderstorm. The lightning distribution was generally consistent with the movement direction of the convective weather. Lightning activity was frequent and densely distributed in the southwestern part of Guizhou Province, with the maximum density reaching 28 flashes per 0.1˚ × 0.1˚ grid. Areas with high lightning density corresponded well with regions of maximum precipitation. The lightning polarity was predominantly negative, with negative flashes accounting for 62%. During the thunderstorm period in Guiyang City, three radar images and the lightning polarity distribution map revealed that the winter convective precipitation was relatively weak, with a maximum composite reflectivity of 55 dBz. The convection was loosely organized and moved rapidly. Lightning was distributed ahead of the radar echo movement. Therefore, lightning monitoring and early warning systems can be utilized to assess the development stage and direction of elevated thunderstorms, facilitating rapid decision-making and the issuance of advance warning information.