桂林市“06.07”大暴雨成因分析

Analysis of "06.07" Guilin rainstorm causes

本文利用常规气象资料、卫星云图、雷达产品等资料,从大气环流特征、物理量场、K指数、沙氏指数及降水云团的发展演变等方面对2007-06-07桂林市的大暴雨过程进行分析。结果表明:这次过程,500hPa副热带高压减弱南退,低纬西风带盛行多波动小槽;700hPa西南低空急流带来强盛的水汽辐合;850hPa低涡切变在桂林附近生成并维持,同时地面相应位置有弱静止锋生成。高、中、低空环流形势的良好配合,是此次大暴雨产生的真正原因。

In this paper, the conventional meteorological data, satellite images and radar products were used to analyze ＂06. 07＂ Guilin heavy rain from the atmospheric circulation features, the physical quantity fields,K index,SI index and the development of the cloud and so on. The result shows that in this process, the subtropical anticyclone on 500hPa was weakened and retreated southward, multimode trough prevailed in the low latitude; southwest low-level jet brought strong vapor convergence on 700hPa;the low vortex shear generated and maintained in the vicinity of Guilin, while the weak stationary front is generated on the corresponding location of the ground. It is the real reason of this rainstorm that high lever,medium lever and low lever circulation coordinated with a good situation.