摘要
利用常规气象资料、新一代雷达和卫星云图资料等,分析了2008年7月1日鄂东北特大暴雨过程中尺度扰动系统的发生发展、暴雨中尺度对流系统(MCS)结构特征以及地形对中尺度系统的影响。结果表明,鄂东北暴雨与中尺度气旋的发生发展关系密切,红安等地特大暴雨就是中尺度气旋波冷切变上激发的多个β中尺度对流系统相继东移产生的;中尺度气旋形成于黄淮锋面气旋波发展阶段,雷达反射率因子形态、结构特征较好地反映了该中尺度气旋波发展过程;对流易在红安西侧加强,同冷空气沿大别山和桐柏山之间南下与天气尺度西南气流交汇形成局地中尺度辐合线有关;红外云图上特大暴雨MCS形态为指状云团,由不同生命史阶段的子云团构成,是产生持续性强降水的云团的显著特征。
Using conventional observational data,radar data,satellite images and so on,the excessive rain in northeast Hubei province on 1 July 2008 is comprehensively analyzed focusing on the occurrence and development of mesoscale disturbance system,the structure characteristics of the heavy rain mesoscale convective system,and the terrain effect on mesoscale system.The results show that heavy rain in northeast Hubei province is closely related to the occurrence and development of mesoscale disturbance system.The successive eastward movement of the meso-β-scale convective systems stimulated by the mesoscale cyclone wave cold shear exactly results in the excessive rain in Hongan.The mesoscale cyclone is formed in the developmental stage of Huanghuai front cyclone wave,which developmental process can be well revealed by the form and structural feature of radar reflectivity factor.The cold air moves southward between the Dabie mountain and Tongbo mountain,joins with the southwest stream of synoptic scale,results in the local mesoscal convergence line,which is the mechanism for the easy enhancement of convection in the west Hongan.By the composition of daughter clouds in different growing period,the MCS producing excessive rain shapes finger cloud in infrared cloud imagery,and remarkably features the cloud cluster which emergences the sustained heavy rain.
出处
《暴雨灾害》
2012年第4期306-312,共7页
Torrential Rain and Disasters
基金
中国气象局预报员专项(CMAYBY2013-043)
