2022年6月20日阳春山区大暴雨特征分析

Analysis of the Characteristics of the Heavy Rainfall in Yangchun Mountain Area on June 20, 2022

利用常规气象观测资料及ERA5 0.25˚ × 0.25˚再分析资料,对2022年6月20日阳春山区大暴雨过程的环流背景及影响系统进行分析,结果表明: 这是华南前汛期一次强对流天气。在高热力不稳定条件下,阳春本地存在强比湿区、稳定少动的地面辐合线,上升运动显著增强,形成“列车效应”,激发了强降水天气的发生。造成此次降雨的直接原因是中尺度对流系统(MCS)连续多次在阳春本地生消。Utilizing conventional meteorological observation data and ERA5 0.25˚ × 0.25˚reanalysis data, this study analyzes the circulation background and influencing systems of the heavy rainfall event in the Yangchun mountainous area on June 20, 2022. The results indicate that this was a strong convective weather event during the early flood season in South China. Under conditions of high thermal instability, there was a strong specific humidity area and a stable, quasi-stationary surface convergence line in Yangchun, which led to a significant enhancement of upward motion, forming a “train effect” and triggering the occurrence of heavy rainfall weather. The direct cause of the rainfall was the continuous formation and dissipation of mesoscale convective systems (MCS) in the Yangchun area on multiple occasions.