2014年5月10-11日柳州强降水过程诊断分析

An Analysis on the Heavy Precipitation on May 10 to 11th, 2014 in Liuzhou

利用Micaps资料、地面加密自动观测资料、NCEP/NCAR的1°×1°每6h再分析资料,对2014年5月10-11日发生在柳州的一次强降水过程进行了诊断分析。结果表明:500h Pa南支槽、850h Pa低涡切变线及低空急流、地面冷锋为此次降雨过程提供了有利的天气尺度背景场;近地层冷空气入侵是本次过程的触发机制,高层强辐散以及低层辐合的有利配置为此次强降水的产生提供了较好的动力条件;强盛的西南急流提供了较好的水汽及能量条件;水汽通量散度、涡度中心值的强弱变化及移动均与强降水中心有着很好的对应关系。

In this paper, the analysis of a heavy precipitation on May 10 to 11 th, 2014 in Liuzhou is performed by using Micaps data, surface intensive observations data, and NCEP / NCAR 1.0x1.0degree reanalysis（ every 6 hours） data. The results show that 500 h Pa south branch groove, 850 h Pa low vortex shear line, and surface cold front provided a favorable synoptic scale background field for the heavy precipitation; the invasion of the cold air of surface layer is the triggering mechanism of the precipitation, and the assemblage of upper-level divergence and lower-level convergence created a suitable dynamic environment for its occurrence; the strong southwest jet stream provided a preferable vapor and energy condition for the heavy rainfall; the vapor flux divergence and the change of the intensity of the center of vorticity as well as its movement correspond well with the heavy precipitation center.