2020年石嘴山市一次暴雨过程的诊断分析

Diagnostic Analysis of a Rainstorm Process in Shizuishan City in 2020

主要利用常规气象资料、NCEP 1°×1°再分析资料及多普勒雷达等气象资料,对石嘴山市2020年8月11日暴雨天气过程主要影响系统、降水过程发生前后其影响区域的动力、热力、水汽等物理演变特征进行了天气学诊断分析。结果表明:此次石嘴山市暴雨天气过程是由500 hPa冷槽,700 hPa暖式切变线、低空急流共同影响形成的;其中,上干冷、下暖湿的不稳定层结,低层辐合高层辐散是本次暴雨发生和维持的主要指标,从雷达回波来看,此次降水为层状云与对流云叠加的混合型降水,是由新的对流单体不断产生使回波发展引起的。

Used conventional meteorological data and NCEP 1 ° × 1 ° reanalysis data and Doppler radar and other meteorological data to make synoptic diagnosis and Analysis on the main influence system of the rainstorm weather process on August 11, 2020 in Shizuishan City, and the physical evolution characteristics of the power, heat, water vapor and so on in the affected area before and after the precipitation process. The results showed that the rainstorm process in Shizuishan was formed by the joint influence of 500 hPa cold trough, 700 hPa warm shear line and low-level jet;Among them, the unstable stratification of dry and cold in the upper and warm and wet in the lower, lowlevel convergence and high-level divergence are the main indicators for the occurrence and maintenance of this rainstorm. From the radar echo, the precipitation was a mixed type of precipitation superimposed by stratiform clouds and convective clouds. The continuous generation of new convective cells causes the echo development.