Abstract:

A local heavy rain occurred in the southernmountainous region of Yongchang County on July 14, 2006 was analyzed synthetically from several aspects of physical quantities, moisture condition, p recip itation intensity, satellite images and radar features. Results show that the wind shear convergence at the level of 500 hPa ismain factor resulting in thisweather event, and the wind vertical shear p rovides favorable conditions to ascent development of airflow; the convective cells caused by the external flow of vortex cloud system bring on this strong convective p recip itation. Meanwhile, we found that analysis on energy and Showalter index fields could be a good indication to strong convective weather forecast.

Key words: Yongchang, heavy rain, analysis

摘要：

对2006年7月14日发生在甘肃省永昌县南部山区的局地强暴雨从天气学、物理量场、水汽条件、降水强度、卫星和雷达特征等方面进行了综合分析,发现500 hPa气旋式风切变是局地强降水形成的主要形势诱发因子,风的垂直切变为上升运动的维持提供了有利条件,有利于对流的产生和发展;由涡旋云系外部气流引发的对流单体,造成了这次局地强对流降水。同时发现高能区和Si场的分析对强对流天气的预测有良好的指示作用

关键词: 暴雨, 分析, 甘肃永昌