辽宁一次大到暴雨天气过程分析

Analysis of A Heavy Rainstorm Process in Liaoning Province

利用天气图、物理量场、卫星云图、单站气象要素等,对2009年8月18～20日辽宁一次典型的大到暴雨天气过程进行了综合的分析。结果表明,该过程是一次由高空槽和副高共同影响的一次天气过程,贝加尔湖分裂冷空气与河套冷空气东移成涡,副热带高压西伸北抬,其边缘暖湿气流切入。低空急流加快了水汽的输送,高空急流出口右侧588线外围出现几个比较旺盛的中尺度对流云团逐步与西风带系统合并,造成此次强烈的混合性降水过程。

Based on the synoptic chart,physical field,satellite nephogram and meteorological elements from a single station,a weather process of typical rainstorm occurring in the liaodong peninsula involved wide area during the period of August 18th to 20th of 2009 was integratively analyzed. It was showed that the weather process resulting from both the upper trough and the subtropical high. The trigger mechanism might lie in ： the Baikal cyclone splitted cold air and the riverain cold air going eastward, forming eddy,the subtropical high going up westward and northward with warm wet flow cutting in via its rim. The upper jet stream accelerated the transportation of cold air and vapor,on which right saw several ac- tive convective cloud cluster, gradually combining with the Baikal cyclone going southward. Then the heavy rainfall occurred. On the analysis of the physical field and surface meteorological elements,this process was a typical rainstorm situation.