2020年7月8—11日柳州持续性暴雨过程的环境条件及模式可预报性分析  

The Analysis of Environmental Conditions and Model Predictability of Continuous Rainstorm in Liuzhou on July 8 11, 2020

作　　者：李宜爽 LI Yishuang(Liuzhou Meteorological Bureau,Liuzhou,Guangxi 545001)

机构地区：[1]柳州市气象局,广西柳州545001

出　　处：《农业灾害研究》2022年第4期51-55,共5页Journal of Agricultural Catastrophology

摘　　要：利用常规观测资料、区域自动站资料、欧洲中期天气预报中心开发的时间分辨率1 h,水平分辨率0.25°×0.25°的新一代再分析资料ERA5,分析了柳州2020年7月8—11日一次持续性强降水的特征及其成因。结果表明:西太平洋副热带高压和高空槽的稳定维持是出现持续性暴雨的天气尺度原因;整个过程期间,柳州地区700 hPa以下有西南风急流并伴随风速的脉动,低空以及超低空急流输送的暖湿气流不断在柳州地区辐合,为暴雨的产生提供了源源不断的水汽;南风风速在柳州北部地区的辐合致使强降水在柳州北部地区维持。在低层偏南气流增强的情况下,应尤其注意元宝山地区可能出现的强降水,加强短临监测和预报预警。Analysed the characters and reasons of heavy precipitation happened in Liuzhou on July 8—11, 2020, making use of conventional observational data, data from regional automatic weather station, and ERA5 reanalysis(Temporal Resolution: 1h;horizontal resolution: 0.25°×0.25°).As a result, the synoptic scale reason of the continuous rainstorm was the stable maintenance of subtropical high and upper trough over the Western Pacific. During the entire process, there was a southwest jet stream with wind speed fluctuation below 700 hPa in Liuzhou area, and the warm and humid air carried by low and ultra-low jet stream continued to converge in Liuzhou area,providing a steady flow of water vapor for the generation of rainstorm. What’s more, the convergence due to the wind speed of south wind in the northern part of Liuzhou, resulted in the continuous heavy precipitation. In the case of the strengthening of southerly airstream at the lower layer, special attention should be paid to the possible heavy precipitation in Yuanbaoshan area, and short-impending and monitor, and prediction and early warming should be beefed up.

关 键 词：持续性暴雨 地形 水汽辐合 模式预报 

分 类 号：P458.121.1[天文地球—大气科学及气象学]