一次非典型西南低涡与降水过程相互关系的天气学分析

The Synoptic Analysis about the Relationship between an Atypical Southwest Vortex and a Precipitation Process

从大气加热角度分析了发生于2014年10月27~28日的一次非典型西南低涡生成、发展过程及其降水特征,揭示了西南低涡和降水系统之间的相互关系。得到以下结论:(1)西南低涡发生之前的降水使得降水区空气的非绝热加热率随高度不断增加从而促进了此次西南低涡的生成;(2)此次西南低涡的降水主要以对流性降水为主,降水大值中心位于涡心的偏东侧;(3)强盛期的西南低涡伴随有次级环流,次级环流既促进了低涡的进一步发展,又有利于触发涡心东侧的对流从而引发强降水。

An atypical Southwest vortex （ SWY） that occurred during 27 ？28 October 2014 and its precipitation process are investigated by means of atmospheric heating analysis. This paper focuses on the relationship between the SWY and the pre-cipitation process. The main results are as follows ： （1） the precipitation process occurred before the SWY leads to the adiabat-ic heating rate increase with height, which made contribute to the genesis of the SWY. （2） Convective precipitation is the main part of the precipitation related to the SWY, and the more precipitation area is mainly distributed in the east of the vortex cen-ter. （3） There is a secondary circulation develops in the mature stage of the SWY, it can not only make for better development of the SWY, but also trigger the convection in the east of the vortex center and lead to heavy rainfall.