湖南春夏季混合强对流天气过程对比分析  

Comparative analysis of mixed severe convective weather processes in spring and summer in Hunan

作　　者：王起唤 姚蓉 周长青 王强[1] 张昆[1] WANG Qi-huan;YAO Rong;ZHOU Chang-qing;WANG Qiang;ZHANG Kun(Huaihua Meteorological Bureau,Huaihua 418000,Hunan,China;Hunan Meteorological Observatory,Changsha 410118,China;Key Laboratory of Preventing and Reducing Meteorological Disaster,Changsha 410118,China)

机构地区：[1]怀化市气象局,湖南怀化418000 [2]湖南省气象台,长沙410118 [3]气象防灾减灾湖南省重点实验室,长沙410118

出　　处：《湖北农业科学》2021年第19期65-74,共10页Hubei Agricultural Sciences

基　　金：湖南省气象局重点课题(XQKJ16A002);湖南省预报员专项(XQKJ19C006)。

摘　　要：利用常规观测资料、NCEP再分析资料、多普勒雷达资料,对比分析湖南春季的2019年3月20日(简称“3·20”)和夏季的8月21日(简称“8·21”)混合型强对流天气。结果表明,“3·20”是西风带系统下的暖平流强迫类型,带来冰雹和短时强降水,“8·21”是副高边缘的准正压类型,带来雷暴大风;“3·20”无明显冷暖空气交汇,“8·21”深层垂直风切不显著,这两点易导致预报中对强对流的忽视;两个过程分别有上干下湿和混合型的探空曲线,层结特征的差异有不同指示意义;“3·20”较“8·21”有更好的水汽输送条件,两者的热力条件均有低层暖湿对流不稳定层,上部干冷空气侵入的特点;雷达特征上,两者均产生超级单体风暴,存在三体散射、高悬强回波和径向速度大值区、中层径向辐合等特征差异,指示了以冰雹或雷暴大风为主。春夏季节混合强对流的相似点是预报工作中需关注的重点,对于主要类型、落区等要素预报预警发挥关键作用。Based on the conventional observation data,NCEP reanalysis data and Doppler radar data,the mixed severe convective weather on March 20,2019 in spring(referred to as"March 20")and August 21,2019 in summer(referred to as"8·21")in Hunan province was compared and analyzed.The results show that"3·20"was the warm advection forcing type under the westerly belt sys⁃tem,which brought hail and short-term heavy precipitation,and"8·21"was the quasi barotropic type at the edge of subtropical high,which brought thunderstorm gale.There was no obvious intersection of cold and warm air in"3·20"and no significant deep vertical wind shear in"8·21",which easily led to the neglect of severe convection in the forecast.The two processes had two kinds of sonde curves of upper dry and lower wet type and mixed type respectively,and the difference of stratification characteristics had different in⁃dicative significance.Compared with"8·21","3·20"had better water vapor transport conditions.Both thermal conditions had the characteristics of low warm and humid convection unstable layer and upper dry and cold air intrusion.In terms of radar characteristics,both produced supercell storms,there were characteristic differences such as three body scattering,high hanging strong echo,high ra⁃dial velocity area,middle-level radial convergence,which indicates that hail or thunderstorm wind was the main.The similarity of mixed strong convection in spring and summer was the focus of prediction work,which played a key role in the forecast and early warn⁃ing of the main types and falling areas.

关 键 词：混合型强对流 不稳定层结 三体散射 湖南春夏季 

分 类 号：P458[天文地球—大气科学及气象学]