粤北佛冈县两次特大暴雨过程对比分析  

Comparative Analysis of Two Heavy Rain Processes in Fogang County.Northern Guangdong

作　　者：陈洁雯 张金宇 王文星 黄永基 骆宇豪 CHEN Jiewen;ZHANG Jinyu;WANG Wenxing;HUANG Yongji;LUO Yuhao(Fogang Meteorological Service,Fogang 511600;Renhua Meteorological Service,Renhua 512300)

机构地区：[1]佛冈县气象局,广东佛冈511600 [2]仁化县气象局,广东仁化512300

出　　处：《广东气象》2024年第5期31-35,共5页Guangdong Meteorology

摘　　要：利用佛冈国家气象站和区域自动气象站逐小时降雨资料,Micaps探空资料和ECMWF的ERA5分辨率为0.25°×0.25°再分析资料,分别对佛冈县前汛期两次特大暴雨过程2020年6月7—9日(简称“6.7”暴雨过程)和2022年5月10—13日(简称“5.10”暴雨过程)进行对比分析,结果表明:两次过程均发生在高层辐散维持、中层短波槽东移和低涡切变南压的背景下,为持续性降水提供了动力条件;西南低空急流带来源源不断的水汽和能量。不同的是,“6.7”暴雨过程为一次明显的暖区暴雨,而“5.10”暴雨过程是一次锋面降水。“6.7”暴雨对流层低层及边界层水汽均来自南海,水汽来源较一致;“5.10”暴雨源于北方的偏北气流与西南气流冷暖交汇。低空急流的日变化规律以及急流与降水在出现时间和强度上具有一定的对应关系。Using the hourly rainfall data of a national meteorological station and regional automatic weather stations in Fogang,the Micaps sounding data and ERA 5 reanalysis at the resolution of 0.25°×0.25°from the ECMWF,two unusually heavy rains,taking place on June 7-9,2020 and May 10-13,2022 respectively in the annually first rainy season of the county,were analyzed respectively.The results are shown as follows.Both processes occurred under the background of upper-level divergence maintenance,eastward movement of a mid-level shortwave trough and southward advancement of a low vortex and a shear,which provided dynamic conditions for persistent precipitation.A southwest low-level jet stream brought a steady stream of water vapor and energy.The difference is that the 2020 rainstorm was an obvious warm-sector process,while the 2022 rainstorm was a process of frontal precipitation.For the 2020 rainstorm,the water vapor in the lower troposphere and boundary layer came consistently from the South China Sea,and for the 2022 rainstorm,the water vapor originated from the convergence between a cooler northerly airflow and a warmer southwesterly airflow.Analysis of the two rainstorms reveals the diurnal variation of the low-level jet stream and the corresponding relationship between the jet and precipitation in the occurrence time and intensity.

关 键 词：天气学 特大暴雨 水汽条件 佛冈县 

分 类 号：P44[天文地球—大气科学及气象学]