景德镇地区一次早春飑线天气过程分析及数值模拟

利用常规高空、地面、雷达观测资料和FNL1°×1°再分析资料,应用天气学方法和数值模拟方法对2016年4月3日景德镇地区一次早春飑线天气过程进行了分析。结果表明:高空冷涡低槽引导的冷空气与西南暖湿气流强烈对峙是此次飑线过程的环流背景。高低空急流耦合作用加强了大气的垂直上升运动和锋面的次级环流,造成赣北地区上空大气具备较强的动力不稳定。回波强度超过55 dBz的低质心强对流云体是导致景德镇地区出现5 min降水量达14.3 mm强降水的重要原因。飑线的快速移动和近地面超20 m/s的大风速核可预示下游测站有大风出现。飑线前部辐合明显,上升运动剧烈,有利于强回波的发展。冷池的强度变化、持续时间与此次飑线的维持有关。

Analysis and numerical simulation of a squall line process in early spring in Jingdezhen area

Based on conventional high altitude observation data, ground observation data and radar data, a squall line process happened in early spring in Jingdezhen on April 3, 2016 was analyzed by using high resolution numerical simulation method. The results showed that the strong confrontation between the cold air guided by the upper cold vortex trough and the southwest low level jet provided an important background for the squall line process. The coupling of high and low level jet strengthened the ascending motion and frontal secondary circulation, and anomalous instability parameters provided strong dynamic instability conditions for the storm. The low centroid strong echo greater than 55 dBz was a significant reason for the occurrence of heavy rainfall. The fast moving squall line and the great wind speed center over the ground indicated strong winds in the downstream stations. The simulated results indicated that the front of the squall line was convergent and the upward motion was violent, which was conducive to the development of strong echo. The intensity and duration of the cold pool were well related to the maintenance of the squall line.