本文基于 2010-2019 年辽宁东南部复杂地形区域的观测降水数据，筛选出 44 次暴雨事件（TRECT），结合合成分析方法及绕流、爬流方程对研究区域低层风场的分解方案，系统探究了该类事件的环流前兆、环流场的共性特征以及地形对区域性暴雨的动力影响机制。结果表明：（1）TRECT事件发生前6天，欧亚大陆对流层中层表现为中阻型阻塞高压，随后贝加尔湖浅槽东移发展，事件当天副热带高压北上加强，关键区西部上空形成斜槽，对流层低层出现闭合气旋性环流，地面华北低压发展东移，关键区位于倒槽顶部，为范围降水提供了有利的环流背景。（2）事件鼎盛期，爬、绕流在关键区地形主体呈现南强北弱的特征，大值区集中于长白山余脉的喇叭口地形区域，爬流强度达 4 m·s-1以上的区域位于喇叭口低地势山坡南侧，绕流则环绕于高地势山体周边，且爬流和绕流经向分支起主导作用。爬流和绕流分别以翻越和绕行山体的方式进入喇叭口，路径主要有来自黄海洋面和朝鲜境内的两支气流。（3）在喇叭口区域，爬流贡献的上升运动占整个系统上升运动的 80% 以上，是降水增幅的主要动力来源，绕流则在地形作用下形成局地正涡度，进一步增强了降水的动力条件。本研究揭示了长白山余脉复杂地形区域暴雨的前期大尺度环流系统演变特征，探究了该区域暴雨的前期环流前兆，并通过中尺度地形动力强迫作用，重点分析了辽宁省东南部喇叭口地形的抬升辐合效应、绕流涡度发展特征，为提升区域山地型暴雨预报准确率提供了理论依据。

Based on the observed precipitation data from 2010 to 2019 in the complex terrain region of southeast‐ ern Liaoning，this study identified 44 torrential rain events（TRECT）. By employing composite analysis methods and decomposing the lower-level wind field using flow-over and flow-around equations，the circulation precur‐ sors，common characteristics of circulation fields，and the dynamic impact mechanism·s of topography on re‐ gional torrential rain were systematically investigated. The results indicate that：Six days prior to the occurrence of TRECT events，the mid-troposphere over the Eurasian continent exhibited a blocking high pattern，followed by the eastward movement and development of a shallow trough near Lake Baikal. On the day of the event，the subtropical high moved northward and intensified，forming a slanting trough over the western part of the key ar‐ ea，with a closed cyclonic circulation appearing in the lower troposphere. The North China low-pressure system developed and moved eastward，positioning the key area at the top of the inverted trough，providing a favorable circulation background for widespread precipitation. During the peak period of the event，the flow over and around the terrain in the key area showed stronger southern and weaker northern characteristics，with high-value areas concentrated in the trumpet-shaped terrain region of the Changbai Mountain's foothills. Areas with flowover speeds exceeding 4 m⋅s-1 were located on the southern slopes of the low-altitude hills in the trumpet-shaped area，while flow-around was observed around the high-altitude mountains，with meridional branches of both flows playing a dominant role. The flow-over and flow-around entered the trumpet-shaped area by crossing and bypassing the mountains，respectively，primarily from two air stream·s originating from the Yellow Sea and the Korean Peninsula. In the trumpet-shaped area，the upward motion contributed by the flow-over accounted for more than 80% of the total system's upward motion，serving as the main dynamic source for precipitation en‐ hancement. The flow-around，under the influence of topography，formed local positive vorticity，further enhanc‐ ing the dynamic conditions for precipitation. This study systematically investigates the evolutionary characteris‐ tics of precursor large-scale circulation system·s associated with torrential rain events in the complex topography of the Changbai Mountain foothills，exploring atmospheric circulation precursors preceding extreme precipita‐ tion. Through mesoscale topographic dynamic forcing mechanism·s，it specifically elucidates the orographic lift‐ ing-convergence effect and flow-around vorticity development within the trumpet-shaped terrain of southeastern Liaoning Province. It provides a theoretical basis for improving the accuracy of regional mountain type rainstorm forecast.