邵阳市冬季大到暴雨气候特征分析

Analysis on the Climatic Characteristics of Heavy Rainstorm in Shaoyang City in Winter

利用邵阳市国家基本站和国家基准站共10个代表站地面气象观测1961年1月~2018年12月共58年的降水资料,统计分析了邵阳冬季(12月至2月)大到暴雨天气事件的时空特征及主要影响天气系统。结果表明:1) 邵阳冬季大到暴雨天气事件是一种小概率事件。2) 造成邵阳冬季暴雨天气事件的主要影响系统是高空槽东移、中低层切变线、低空急流和冷空气南下共同影响。3) 冬季大到暴雨的发生年代际变化明显。4) 产生冬季大到暴雨的物理条件与充沛的水汽、低空急流和辐合上升运动密切相关。

Based on the ground meteorological observation data of 58 years of precipitation from January 1961 to December 2018 at 10 representative stations of national basic station and national base station in Shaoyang city,the temporal and spatial characteristics of severe to heavy rain weather events in winter(December to February)in Shaoyang city and their main influence on the weather system were statistically analyzed.The results show that:1)the winter heavy rain event in Shao-yang is a small probability event;2)the main influencing systems of the winter rainstorm in Shaoyang are the eastward movement of the upper trough,the shear line in the middle and lower layers,the low-level jet stream and the southward movement of the cold air;3)the interdecadal change of the occurrence of heavy rain in winter is obvious;4)the physical conditions that produce winter rainstorms are closely related to abundant water vapor,low level jet stream and convergence upward movement.