2023年7月6~7日扬州地区特大暴雨过程具有覆盖范围广、短时雨强大、强降水持续时间长的特点。本文利用自动气象站资料、MICAPS气象数据资料、NCEP再分析资料、雷达回波资料等对此次降水过程进行诊断分析。结果表明:低纬强大稳定的副高与高纬稳定少动的冷涡对峙,加之低层范围宽、强度大的西南急流持续输送水汽,形成冷暖气流长久激烈交汇,是造成本次强降水的背景基础和必要条件。江淮西部有利的动力、热力、能量等中尺度对流触发条件和南北风场辐合,提供了列车效应有利的环境条件。暖区低质心高效降水和列车效应叠加,导致此次特大暴雨的发生。大尺度模式对特大暴雨多存在漏报,区域模式对降水落区等细节把握欠佳,需多关注潜势预报和新产品的应用,并提升中尺度分析能力从而提高极端降水的预报准确性。The extremely heavy rainstorm process in Yangzhou on July 6~7, 2023 is characterized by wide coverage, strong short-term rain and long duration of heavy rainfall. Diagnosis and analysis of this precipitation process using automatic weather station data, MICAPS meteorological data, NCEP reanalysis data and radar echo data. The results indicate that the confrontation between a strong and stable subtropical high at low latitudes and a stable and less moving cold vortex at high latitudes, coupled with the continuous transport of water vapor by the southwest jet stream with a wide range and high intensity at low latitudes, formed a long-term and intense intersection of cold and warm air currents, which is the background basis and necessary condition for this heavy rainfall. The favorable mesoscale convective triggering conditions such as power, heat, and energy in the western Jianghuai region, as well as the convergence of the north-south wind field, provide favorable environmental conditions for the train effect. The superposition of the low centroid efficient precipitation in the
利用地面高空观测资料,结合ERA5再分析资料和多普勒雷达、乡镇自动站雨量等,对2023年4月18日新余市一次暴雨天气过程进行分析,结果表明:此次暴雨过程发生在高空槽东移,切变线南压的形势下,夜间低层西南急流加强输送了水汽和能量条件,低层暖湿特征显著,大气处于对流不稳定状态,降水的可预报性较高。大暴雨雨带位主要于宜春中部,新余处于大暴雨带的南面,且位于切变线南侧、700 hPa急流出口区的左侧、850 hPa和925 hPa急流轴上,产生了较强的上升运动条件,有利于强降水的出现。Based on the surface observation data at high altitude, combined with ERA5 reanalysis data, Doppler radar, township automatic station rainfall, etc., a rainstorm weather process in Xinyu on April 18, 2023 is analyzed. The results show that the rainstorm process occurred in the shape of the high trough moving eastward and the shear line pressing southward. The low-level southwest jet at night strengthened the transport of water vapor and energy conditions. The low-level warm and humid characteristics are significant, the atmosphere is in a convective unstable state, and the precipitation is highly predictable. The heavy rainstorm belt is mainly located in the middle of Yichun, and Xinyu is located in the south of the heavy rainstorm belt, and on the south side of the shear line, the left side of the 700 hPa jet exit area, and on the 850 hPa and 925 hPa jet axes, resulting in strong upward movement conditions, which is conducive to the emergence of heavy rainfall.
