提利用多普勒天气雷达、探空和逐小时降水量资料，对2010-2012年，滇西南普洱、西双版纳537次短时强降水天气过程进行统计分析，建立三种短时强降水概念模型，分别是：低质心弱辐合型短时强降水、低质心辐合型短时强降水、高质心短时强降水。对比分析了不同类型短时强降水的强度特征、移速特征、生命期特征、垂直风切变特征等，探讨了辐合作用与强降水维持时间的关系、辐合切变量与雨强的关系、DVIL 与降水量的关系。并得出预警方法：满足如下条件时，出现短时强降水的可能较大：（1）低质心强降水中，回波无倾斜特征，强度以40～45 dBz 为主，强度从低层到高层维持或缓慢减弱，大部分回波的H40 dBz ≥H0，且0℃层高度上40 dBz 的回波的累计长度／回波移速≥0．67 h（辐合切变量≥2．2 m·s-1时，累计长度／回波移速≥0．50 h），预报提前时间30～40 min。（2）高质心强降水中，强回波边缘存在宽≥3 km、强度为40～45 dBz 的回波，且0℃层高度上40 dBz 的回波的累计长度／回波移速≥0．47 h，预报提前时间28 min 左右。此外，对短时强降水成因进行了探讨。%Based on Doppler radar data,sounding data and precipitation data,537 flash heavy rain proces-ses in Puer and Xishuangbanna are analyzed.Three short-time severe precipitation models are established, including the flash heavy rain into the low centroid and weak convergence type,the low centroid and con-vergence type and the high centroid type.In addition,comparative analysis is carried out on the features of intensity,velocity,life cycle,vertical wind shear and interrelationships of convergence and heavy rainfall duration,shear line in convergence zone and precipitation intensity,DVIL and precipitations of different types.Then the warning methods are derived as follows:if meeting the following conditions,it is a highly possible to see flash heavy rains.First,in the case of a lower centroid of echo in heavy precipitation,if echo intensity is 40 -45 dBz and not inclined,echo intensity remains unchanged by vertical direction,H40 dBz ≥H0 ,overall length by velocity of echo intensity about 40 dBz is more than or equal to 0.67 h in 0℃layer,we can give warning time of 30 -40 min before flash heavy rainfall.Second,in the case of a high centroid of echo in heavy precipitation,if the intensity of echo is uniform (40-45 dBz),the width of echo is greater than or equal to 3 km on the edge of strong echo,overall length by velocity of echo intensity about 40 dBz is more than or equal to 0.47 h in 0℃ layer,we can give warning time of about 28 min before flash heavy rainfall.Finally,the genesis for flash heavy rains is discussed.
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