杭州市由超强台风“利奇马”引起的一次降水天气过程分析

Analysis of a Precipitation Weather Process Caused by Super Typhoon Lichma in Hangzhou

摘要: 本文应用台风路径及强度资料和欧洲中尺度天气预报中心ERA-Interim再分析资料对2019年8月10日由台风“利奇马”引起的一次暴雨天气过程进行诊断分析，结果表明：中高纬西风槽及西太副高对台风的强度及路径的变化有一定指示作用。从台风前后散度场配置及垂直速度的分析猜测此次台风暴雨主要集中在台风移动方向前侧。暴雨的水汽来源主要为太平洋以及孟加拉湾地区，充足的水汽供应为此次暴雨过程提供了良好的水汽条件，高湿度的气柱配合较强水汽辐合是造成杭州地区极端降水的关键。这种明显的动力条件以及水汽条件可为该杭州市台风暴雨预报与防灾减灾提供参考依据。

Abstract: In this paper, the path and intensity data of the typhoon and the ERA-Interim reanalysis data are used to diagnose a heavy rain weather process caused by Typhoon “Lekima” on 10 August 2019. Results showed that the mid-high latitude westerly trough and the West Pacific subtropical high have a certain indication effect on the intensity and path of the typhoon. From the analysis of the divergence field configuration before and after the typhoon and the vertical velocity, it is predicted that the typhoon rain is mainly concentrated in the front side of the typhoon movement direction. The water vapor sources of the rainstorm are mainly the Pacific Ocean and the Bay of Bengal. Sufficient water vapor supply provides good water vapor conditions for the rainstorm process. The high humidity air column combined with strong water vapor convergence is the key to extreme precipitation in Hangzhou. Such obvious dynamic conditions and water vapor conditions can provide a reference basis for typhoon rain forecast and disaster prevention and mitigation in Hangzhou.