Characteristics of a mesoscale convective system in a warm zone that created an extreme, short rainstorm in Southern China in May 2016

4th International Conference on Water Resource and Environment

地球科学;生态环境科学

Huang, Z.Y.^1 ; Chen, W.^2 ; Xu, M.^1

Institute of Heavy Rain, CMA, Wuhan

430205, China^1

Wuhan Meteorological Bureau, 430000, China^2

关键词: Convective clouds;    Convective precipitation;    Dewpoint temperature;    Guangdong Province;    Mesoscale Convective System;    Precipitation efficiency;    Satellite images;    Strong coupling;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/191/1/012142/pdf
DOI  :  10.1088/1755-1315/191/1/012142

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

An extremely intense rainstorm occurred on 20 May 2016. It had been the heaviest rainfall event recorded in Xinyi, Guangdong Province, China, since 1960. The black body temperature (TBB) output of FY-2B satellite images, weather radar, and NCEP/NCAR reanalysis data were used to investigate the characteristics of a mesoscale convective system (MCS) associated with the rainstorm. Heavy rainstorms formed under the influence of an eastward migration of a low trough at 500 hPa, typical of warm area heavy rain. In front of the 500 hPa trough, there was strong coupling of high and low jet streams, high convective effective bit energy, strong middle and low water vapor convergence and high ground dew point temperature, creating a favorable environment for the formation and development of MCSs. The convective region of the linear convective cloud developed into an organized MCS, and Xinyi's heavy rainfall occurred during the MCS lifecycle from formation to maturity to extinction. Five MCSs, with radar echo intensities of 40-55 dBz, created a 'train effect', which was the main driver of the heavy rainstorm. The strong echoes observed above 40 dBz were below 0C, and the strongest echo center was near 2 km. The convective precipitation system had a low mass center and high precipitation efficiency. The echo top (with intensity ≥ 10 dBz) was as high as 19 km, and there was a deep ice phase growth belt above -10C, which contributed to the heavy rainfall, which peaked at 132.8 mm in one hour.