2023年六盘水市“6·29”突发性大暴雨成因分析

Analysis of the Causes of “6·29” Sudden Rainstorm in Liupanshui in 2023

利用六盘水市国家气象站、区域自动站资料、常规气象资料以及NCEP (1˚ × 1˚)再分析资料,对2023年6月29日贵州六盘水市突发性暴雨天气过程进行分析,结果表明:此次暴雨过程是在西太平洋副热带高压(以下简称副高)北侧,受高空槽、低层切变、地面辐合线和弱冷空气共同影响下产生的。副高西侧的偏南暖湿气流为此次暴雨提供了充足的水汽和不稳定能量,地面辐合线为暴雨的发生提供了触发机制,弱冷空气的补充有利于锋生使对流加强,对流云团在六盘水市北部发展并加强形成中尺度对流复合体(MCC),长时间维持少动,造成六盘水市暴雨累积雨量大、降水强度强、极端性强、强降水落区集中的特点。

Using the data of Liupanshui national meteorological station and regional automatic station, the conventional meteorological data and NCEP (1˚ ×1˚) reanalysis data, the weather process of sudden rainstorm in Liupanshui on June 29, 2023 was analyzed. The results show that the rainstorm process is in the North side of the Western Pacific subtropical High (hereinafter referred to as the subtropical high), is produced under the joint influence of high trough, low layer shear, ground convergence line and weak cold air. The south warm moisture of vice high on the west side provides sufficient water vapor and unstable energy for the rainstorm, ground convergence line provides the trigger mechanism, weak cold air supplement is conducive to the frontogenesis and the convection is strengthened, convection cloud develops in northern Liupanshui and strengthens the formation of mesoscale convection complex (MCC), maintained less movement for a long time results in the characteristics of heavy rainfall, strong precipitation intensity, strong extreme precipitation, and concentrated heavy precipitation in Liupanshui rainstorm.