2013年6月大气环流和天气分析

Analysis of the June 2013 Atmospheric Circulation and Weather

2013年6月大气环流特征为:北半球极涡呈单极型,中心位于格陵兰岛附近,较常年偏弱,我国中高纬地区多高空槽活动;西太平洋副热带高压(以下简称副高)强度较常年偏弱,西段位置多变。6月全国平均降水量为99.9 mm,接近常年同期(99.3 mm);全国平均气温为20.7℃,较常年同期(20.0℃)偏高0.7℃。月内我国主要天气气候事件有:全国发生7次大范围强降雨过程,多站出现极端日降水量,部分地区洪涝灾害较重,23日起长江中下游地区相继进入梅雨期,29日出梅;南方出现今年首次大范围高温天气过程;热带风暴贝碧嘉登陆,登陆时间偏早。

The following are the main characteristics of the general circulation of atmosphere in June 2013. There was only one polar vortex center, whose center was near Greenland, in the Northern Hemisphere with weaker strength compared to normal years. More high-level troughs were active in middle-high lati- tudes. The northwestern Pacific subtropical high was weaker than normal. The monthly mean precipitati- on amount was 99. 9 mm, near climatological normal （99. 3 mm）. The monthly mean temperature was 20.7~C, being O. 7~C higher than normal （20.0~C）. Seven heavy rainfall processes occurred in this month and extreme daily precipitation was recorded at many stations and some places suffered from severe floods. On June 23, the region of middle and lower reaches of Yangtze River stepped into Meiyu period, and out of it on the 29th. Besides, large-scale hot weather hit the Southern China for the first time this year. The tropical storm ＂Bebinca＂ became the first tropical storm landing China this year, and the time of landing was earlier than normal.