长沙低温阴雨雪冰冻天气过程分析

Analysis on the Process of Low Temperature and Rain Snow and Freezing Weather in Changsha

摘要: 本文对2014年2月4~18日长沙市低温雨雪冰冻天气过程进行了系统的分析，通过分析得出此次过程的主要影响系统是北方有强冷空气从贝加尔湖南下影响长江中下游地区，中亚中高纬地区为两槽一脊的天气形势。低纬南支系统活跃，不断有短波槽东移，湖南受南支槽前西南气流控制，中低层西南急流位于西南地区东部至江南中部，持续将孟加拉湾水汽向湖南东北地区输送。高低空形势和地面冷空气相配合，形成了长沙市持续的低温雨雪冰冻天气。

Abstract: Through February 4 to 18, 2014 in Changsha City, low temperature, rain snow and frozen synoptic process were analyzed. The results show that the main influencing system of the process is North strong cold air mass from Lake Baikal affecting local weather in the middle and lower of the Yangtze River, in high latitude weather situation in Central Asia with two troughs and one ridge. Low latitude south branch system is active, and constantly has short wave trough eastward. Hunan suffers the control of the front southwest airflow in southern branch trough, middle and low level southwest jet stream is located in the southwest region of the eastern South Central, the water vapors from the bay of Bengal delivery in northeastern Hunan Province. High altitude situation and the cold air are matched, forming the persistent and low temperature sleet freezing weather in Changsha city.