2018年9月大气环流和天气分析

Analysis of the September 2018 Atmospheric Circulation and Weather

2018年9月大气环流的主要特征是:极涡呈偶极型,中高纬地区西风带为多波型分布,西太平洋副高强度较常年偏弱、位置偏西。全国平均降水量74. 2 mm,较常年同期(65. 3 mm)偏多14%;全国平均气温为16. 7℃,较常年同期(16. 6℃)偏高0.1℃。9月我国大范围的降水有3次,华南和西北地区东部等地出现强降水,局地灾情严重。9月在西北太平洋和南海共有4个台风生成,其中1822号台风山竹和1823号台风百里嘉在我国广东省登陆。月内黑龙江遭受低温冷冻灾害;华西秋雨开始偏晚,云南、四川南部、重庆和贵州南部秋雨强度总体偏强。

The main characteristics of the general atmospheric circulation in September 2018 are as follows.The polar vortex showed a dipole pattern.The circulation presented the distribution of a multi wave pattern in middle high latitudes.The northwestern Pacific subtropical high was weaker and remarkably more westward extended than normal.The monthly mean precipitation amount was 74.2 mm, which is 14% more than normal (65.3 mm). The monthly mean temperature was 16.7℃, 0.1℃ higher than normal. There were three large range heavy rainfall processes over China, which happened in South China and the eastern part of Northwest China, causing serious disaster locally. Four tropical cyclones were generated over northwest Pacific Ocean and the South China Sea. Typhoon Mangkhut (1822) and Barijat (1823) landed in Guangdong Province. Moreover, Heilongjiang Province suffered from low temperature and freezing disaster. Autumn rain for West China came late, but heavy somewhat in Yunnan, southern part of Sichuan, Chongqing and Southern part of Guizhou.