四川盆地三个典型落区西南涡暴雨天气成因的对比分析

本文将2010～2016年多场典型西南涡暴雨个例根据落区分为西北、东北、西南3型进行合成分析，结果表明:（1）四川盆地的地理特征决定其降水分布与地形密不可分；（2）中纬度低值系统（槽/低涡）的位置和强度对落区起到关键作用；（3）盆地内皆有明显的风场辐合。西北/西南型与东北型相比，西北/西南型对应的西南气流在盆地西部很强，而东北型对应的大风区则位于盆地东部。西北型和西南型相比，西南输送气流更强，可以将水汽输送到更北的位置。（4）盆地地区降水前期，落区上空大气水汽充沛，整层水汽和850hPa的比湿高值区与落区位置相当一致。（5）盆地降水与局地层结稳定性密切相关，各个最强降水落区往往与层结最不稳定区域相对应。

Comparative Analysis of the Southwest Vortex Rainstorm Causes at Three Typical Areas in Sichuan Basin

This article is synthetic analysis of the northwest， northeast， southwest type3， which are classified according to fall from more than 2010～2010 typical southwest vortex rainstorm cases，the results show that:（1） the precipitation distribution is closely connected with the terrain in Sichuan basin.（2） the location and intensity of slot or low vortex played a key role to the drop zone.（3） there are obvious wind fields convergence in the basin.Compared with the northeast type and the northeast type，the southwest airflow is very strong in the western part of the basin when the rainfall happens at the northwest/southwest basin， while the big wind speed is located in the eastern part of the basin.（4） the atmospheric water vapor is abundant above the rain belt before the precipitation， and high value zone of water vapor is quite consistent with falling area.（5） the precipitation is closely related to the Stratification stability in the basin，and the most powerful precipitation zones correspond to the most unstable regions of the stratification.