近10年巴州地区春季高影响强降水天气分析

Recent Ten Years Analysis of Heavy Rainfall in Spring of Bayingolin Mongol Autonomous Prefecture

摘要: 2019年5月4~7日巴州地区发生了一次春季转折性、高影响强降水，受浅薄中亚低涡影响先后出现急流冷锋降水、干线触发的强对流降水、低涡气旋降水。强对流降水时段云团的初生位置与地面边界层内不同性质气团交汇点对应，北抬对流云团的冷外流边界触发对流云团再生和增强。强降水发生前巴州东南侧存在水汽补充输送、探空关键参数出现明显增减变量、雷达径向速度上中低层辐合增强。近10年巴州春季发生9场高影响、致灾强降水过程，影响系统包括中亚长波槽、中亚短波槽、中亚浅薄低涡，天气概念模型分为急流冷锋、低槽切变辐合、低涡气旋、急流锋区，急流类强降水的触发多与地面冷锋活动相关，切变、辐合气旋类强降水触发多与干气团水平和垂直方向侵入有关。

Abstract: A transitional and high impact heavy rainfall process happened in Bayingolin Mongol Autonomous Prefecture of South Xinjiang from 4 to 7 on May 2019, which contained multiple configuration types of precipitation process with a succession of fast-flowing cold frontal precipitation, dry line-triggered heavy convective precipitation, and low-vortex cyclonic precipitation influenced by a shallow Central Asian low vortex. The initial location of cloud masses during periods of intense convective precipitation corresponds to the intersection of air masses of different nature within the ground boundary layer, and the cold outflow boundary of northward lifting convective cloud masses triggers the regeneration and intensification of convective cloud masses. The heavy precipitation was preceded by supplementary water vapour transport on the south-eastern side of Bayingolin Mongol Autonomous Prefecture. Before the heavy precipitation, there is significant increase or decrease in key sounding parameters, and enhanced mid- and low-level convergence on radial velocities. In the past 10 years, nine high-impact, disaster-causing heavy precipitation processes occurred in spring. The influencing systems include the Central Asian long wave trough, the Central Asian shortwave trough, and the Central Asian shallow low vortex, and the weather concept models are divided into rapid cold fronts, low trough shear convergence, low vortex cyclones, and rapid frontal areas. The triggering of rapid-type heavy precipitation is mostly related to the cold front activity on the ground, and the triggering of shear and convergence cyclones is mostly related to the horizontal and vertical intrusion of dry air masses.