2011年浙江梅雨期2次强对流天气对比分析

A Comparative Analysis of Two Severe Convective Events in Zhejiang during the Meiyu Period of 2011

强对流天气是浙江省主要的灾害性天气之一.利用常规观测资料,Micaps、多普勒雷达等资料,对浙江省2011年梅雨期2次强对流过程进行对比分析,结果表明:6月9日强对流,主要表现为冰雹和雷雨大风;6月18日强对流,主要表现为短时强降水.天气形势上,前者为西风槽型,后者为大陆高压型,2次过程都对应一支西南急流,显然后者的强度更大.探空和对流指数上,前者上干下湿,不稳定条件和对流指数优于后者.雷达回波图上,前者中高层强回波悬垂,出现"穹隆"结构,强回波平均高度和垂直积分液态含水量明显高于后者,后者为回波结构致密,低质心高效率的强降水回波.

Using conventional observation meteorological data,MICAPS data and Doppler radar data,etc.,the two severe convective events in Zhejiang during the Meiyu period of 2011 were analyzed.The first event took place on 9th June accompanying hail with intense gust,and the other took place on 18th June with short-time heavy rainfall.The results showed that the two events differed greatly from each other in the circulation pattern.In addition,the lower southwest jet conduced more to the occurrence of the 18th June event,but the radiosond,convective indexes,the average strong echo height with reflectivity and VlL values conduced more to the occurrence of the 9th June event.Besides,the radar data showed the details of vault structures and strong echo tendency on the middle-high levels for the 9th June event,and showed the details of dense structure,high efficiency and low-quality strong precipitation echo for the 18th June event.