2009年6月两次强对流天气的对比分析

Contrast and Analysis of Two Severe Convective Weather Processes in June 2009

基于中尺度自动站、雷达拼图资料,分析了2009年6月两次典型强对流天气过程的大风变化,阐述了多普勒雷达拼图的水平结构特点,并对两次天气过程进行了对比研究。结果表明,①第1次强对流过程8～10级大风的站点数远小于第2次的站点数;第1次过程在沿淮淮北多数地区出现大风,分布范围较小;第2次过程在大别山区、皖南山区之外的全省多数地区出现大风,分布范围大得多。②第1次强对流天气过程风速变化主要表现为一个峰值,第2次过程却在北部地区有2个峰值。③第1次过程主要由一次雷达回波过境造成,第2次过程则由两次雷达回波过境造成;第1次过程有一次回波单体合并现象,第2次过程有两次回波单体合并现象,合并之后对流单体得到加强。

Based on the data of mesoscale weather stations and the radar mosaic, the gales in two typical strong convection weather processes in June, 2009 are analyzed. The data come from the mesoscale experiment base of the key laboratory of Anhui Province. One process occurs on June 3-4, and the other process on June 14. The horizontal features and the characteristics of Doppler radar mosaic are studied. The two weather processes are compared. The results are as follows. （1） The 8-10 level gale number in the first severe convection process is less than that in the second process. The gales in the first process appear mostly in areas along Huai River and Northern Huai River. The gales in the second process appear mostly in areas of Anhui Province. The distribution range of the second process is much bigger than the first process. （2） The wind speed in the first process has a peak value, and in the second process has 2 peak values in the north area. （3） The first process is mainly created by radar echo once, and the second process is created by radar echo twice. The first process has one echo mergence phenomenon, and the second process has two echo mergence phenomena. The convective cell is enhanced after the mergence. Motion direction of the two processes is the same, that is, east by south. The intensity of the maximum radar echo is more than 55dBz.