中文摘要：

利用多种资料对2014年6月28—29日云南省冷锋切变型强降水进行诊断分析,并利用WRF中尺度模式,对此次过程进行地形敏感性数值试验.结果表明去除山脉地形后,全省区域降水量明显减弱,大雨、暴雨的落区急剧缩减;降水量的变化差异主要由降水强度的变化引起.山脉对低层冷空气的引导和阻挡作用最为显著,四川东部到贵州一带的东北气流经乌蒙山加速进入到滇中地区,受哀牢山、无量山和横断山脉的阻挡,与青藏高原东南侧沿横断山脉南下的冷平流汇合,在滇中及以东、以北地区盘踞;夏季来自南海的东南气流及来自孟加拉湾的偏西气流均具有高温高湿性质,在山脉的引导和阻挡作用下,与南下受阻的冷空气交汇,形成锋面降水;山脉的强迫抬升机制迫使其周边出现显著的垂直上升运动,强度约0.4~0.7 m/s;在山谷相间的区域,特别是山脉的迎风坡处,水汽通量辐合,其增量可达（0.02~0.07）×10^-6g·s^-1·cm^-2·h Pa-1,有利于当地大雨、暴雨的发生.

英文摘要：

Based on the observed ＂data and output data form WRF, the causes and the influence of mountain terrain on the formation of cold front shear heavy rain in Yunnan Province from June 28 to 29 in 2014 have been analyzed.The results show that taking no consideration of mountain terrain, the precipitation decreased significantly,the heavy rain fall area shrank.The change of precipitation difference is mainly caused by the change of precipitation intensity.The mountains＇ guiding and blocking effect of cold air is significantly apparent.The airflow from Sichuan and Guizhou Province accelerate into the region of Yunnan by Wumeng Mountain, then it is blocked by the Ailao Mountain, Wuliang Mountain and Hengduan Mountains, converging with the cold advection from Qinghai-Tibet Plateau along the Hengduan Mountains, occupying the areas in the east, the north and the middle of Yunnan Province.In summer,the southeast air current from the south China Sea and the west airflow from Bay of Bengal presents properties of high temperature and high humidity, under the guidance and blocking in the mountains, their moving speed slows down and converges with the cold air aforementioned, resulting in frontal precipitation.Mountains＇ forced lifting mechanism forced its surrounding a marked vertical upward movement,inten- sity of 0.4 to 0.7 m/s.In the valleys,especially in the windward side of mountain,water vapor convergence will build up by the effect of mountains,resulting in the increment of （0.02-0.07）×10^-6 g · s^-1 · cm^-2 · hPa^-1.