一次致灾区域性大暴雨成因分析

Analysis of the Causes of a Regional Heavy Rainstorm

本文利用常规观测资料、NCEP再分析资料以及雷达回波等气象资料,对2016年6月21日信阳区域大暴雨天气进行诊断分析。分析结果表明,本此大暴雨天气是在副热带高压环流影响下,配合高空低槽和江淮切变线等天气系统而发生的。低层西南急流和超低空南风急流将海上水汽移至信阳上空,同时受低层辐合、高层辐散影响,促使该区域形成了强烈的上升运动。经测量雷达回波强度为50dBZ,"列车效应"使得该区域保持持续降雨。

In this paper,the meteorological data such as conventional observation data,NCEP reanalysis data and radar echo were used to diagnose and analyze the heavy rainstorm in Xinyang area on June 21,2016.The analysis results showed that the heavy rainstorm occurred under the influence of the subtropical high-pressure circulation,combined with the high-altitude low-slot and the JAC shear line.The low-level southwest jet and the ultra-low-level southerly jet stream moved the sea water vapor to the sky above Xinyang.Affected by low-level convergence and high-level divergence,the region formed a strong ascending motion.The measured radar echo intensity was 50dBZ,and the"train effect"caused the region to maintain continuous rainfall.