Based on hourly precipitation data observed by automatic weather stations of Liaoning province and NCEP grid reanalysis data with resolution of 1°×1°from 2005 to 2015,the characteristics of spatial and temporal distribution and influencing weather systems of extreme long duration rainstorms and the distribution of precipitati-on influenced by different systems were analyzed in this paper.The resluts show that the long duration rainstorms in Liaoning province are widely distributed and can be roughly divided into four easy-occurrence areas.The dura-tion of rain with intensity≥10 mm·h-1is dominated by 6-8 hours which the maximum duration is up to 14 hours and the maximum rainfall intensity is up to 91 mm·h-1.Moreover,the total precipitation is up to 150-200 mm for which duration is 6-7 hours and up to 250-350 mm for which duration is 8-10 hours.The number of rainstorms va-ries significantly from year to year.July and August is a period with high occurrence.The numbers of rainstorms are great in July,while the ranges are narrow.The number of rainstorms is less in August,while the ranges are wide.This rainstorm occurs frequently at 15:00-17:00 and 22:00-02:00.In high weather systems,it is the widest distribution and greatest intensity as well as longest duration for rainfall caused by Okhotsk Sea blocking high,and they are scattered distribution caused by zonal circulation and centralized distribution caused by Baikal Lake bloc-king high,respectively.Among them,the number of the Okhotsk Sea blocking high is the greatest.In surface weather systems,the Northwestern side of high pressure appears frequently,and it can cause rainfall with the grea-test intensity.It is the wide distribution for rainfall caused by Huabei cyclone,centralized distribution caused by the Northwestern side of high pressure and typhoon and Jianghuai cyclone,and scattered distribution caused by Mon-golia cyclone and Huabei cyclone.%利用2005-2015年辽宁省自动气象站逐小时降水资料和NCEP的1°×1°格点再分析资料,分析了辽宁极端长历时暴雨的时空分布特征、影响天气系统和不同天气系统下的降水分布特征.结果表明:辽宁极端长历时暴雨分布广,大致可划分为4个易发区,降水雨强≥10mm·h-1的持续时间以6-8h为主,最长可达14h,最大雨强可达91mm·h-1,总降水量6-7h可达150-200 mm、8-10 h可达250-350 mm;暴雨次数年际变化大,7-8月是多发期,7月过程次数虽多但范围小,8月过程次数虽少但范围大,15-17时和22-02时最容易开始发生该型暴雨;高空影响天气系统中,鄂霍次克海阻塞高压次数最多且造成的降水持续时间最长、雨强最大、分布范围最广,纬向环流型暴雨分布零散,贝加尔湖阻塞高压型暴雨分布相对集中;地面影响天气系统中,高压后部型次数最多且造成的降水雨强最大,华北气旋造成的降水持续时间最长,高压后部型、台风型和江淮气旋型暴雨分布相对集中,蒙古气旋型和华北气旋型暴雨分布零散.
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