2013年12月广西一次暴雨落区变化原因分析

Analysis on the change reasons of a heavy rain fall areas in December 2013 of Guangxi

利用micaps常规观测资料和NCEP再分析资料,对2013年12月13日～17日广西出现持续性强降雨天气的物理量场的分析得出：强降雨主要是由低层切变线和南支槽共同作用引起,各层天气系统对每天强降雨的贡献不尽相同,第一天高空南支槽还比较浅薄,强降雨主要由低层切变线和超低空东南急流引起;第二、第三天强降雨则是由加深东移的南支槽和北抬又南压的低层切变线共同作用引起;第四天降雨中低层转北风,只有500hPa南支槽和700hPa切变线共同影响.

Based on micaps routine observation data and NCEP reanalysis data, , the physical quantity of a persistent heavy rains in Guangxi weather on December 13 - 17 2013 was analyzed, it showed that： heavy rainfall was mainly caused by a combination of low-rise shear line and southern trough, the layers of weather system＇s contribution to the heavy rain every day was not same, the first day of high altitude southern trough is relatively shallow, heavy rainfall is mainly caused by lower shear line and southeast low-level jet stream; The second and the third day of heavy rainfall is carried by deepening east of the southern trough and the north and south of the lower shear line ; The fourth day of rainfall, the lower switched to the north, only 500 hpa southern trough and 700 hpa shear line influenced together.