中文摘要：

根据辽河区实测和调查年最大点暴雨资料与气象资料,分析了极端暴雨的区域特征以及形成极端暴雨的天气成因,揭示了极端暴雨的基本规律。研究表明,辽河区大部分地区年最大24 h暴雨占3 d暴雨的70%以上;暴雨92.1%集中在7—8月,极端暴雨68.1%高度集中在7月下旬至8月上旬;极端暴雨集中分布在黑山山脉、千山山脉迎风山区、鸭绿江山地丘陵区、辽浑太地区;极端暴雨的年际变率大;极端暴雨以中高纬度＂东高西低＂、＂两高一低＂、＂波状流＂、＂经向高压坝＂,中低纬度副热带高压稳定至最高纬度为高空环流形势背景,暴雨天气系统主要有北方气旋、高空槽、单一冷锋、切变线、锢囚锋、高空低涡、东北冷涡、半热带半温带气旋等,通过中纬度西风槽东移、副热带高压北上、低纬度热带气旋北进等天气系统以及山丘区的地形抬升作用共同造成。

英文摘要：

Based on the observed and investigated annual maximum point rainstorms data and meteorological data in the Liaohe River region,the regional characteristics and weather causes of annual extreme point rainstorms are analyzed,and the fundamental rules of the extreme rainstorms occurrence are revealed. The analysis results show that the amount of the annual maximum 24 h point rainstorms accounts for more than 70% of 3 d point rainstorm quantity in most areas of the Liaohe River region. Futhermore,92. 1% of the rainstorms occurs in July and Autumn,and 68. 1% of the extreme rainstorms appears between late July and early Autumn. The spatial distribution of the extreme rainstorms is concentrated on the windward slope of Qianshan and Heishan Mountains and the hilly area of the Yalujiang River basin,as well as the Liao-Hun-Tai River region. The interannual variations of the extreme rainstorms are evident. The extreme rainstorms in the middle and high latitude of East Asia are characterized by ＂East high,West low＂,＂two high one low＂,＂wavy airflow ＂,and ＂warp direction high dam＂,and in the middle and low latitude of East Asia by subtropical anticyclone stability,and in the highest latitude by upper air circulation situation as the background. The main rainstorm weather system has cyclones from the north,upper trough,single cold front,shear line,occluded front,upper vortex,cold vortex from northeast,semi tropical and semi temperate cyclone. The rainstorms usually happen under the combined action of the weather systems,such as middle-latitude westerly trough,subtropical high and tropical cyclones,and topographical uplift of the windward mountain.