2007年7月12-15日河南省大暴雨天气诊断分析

利用常规观测资料和NCEP再分析资料,对2007年7月12-15日河南省黄淮之间的大暴雨过程进行了诊断分析,结果发现:这次暴雨是一次较为典型的西南低涡东北移影响河南省所造成的暴雨,500 hPa西风槽东移过程中,槽前携带的冷空气不断自西北方向侵入西南低涡中心,导致西南涡东移发展,移经河南省,在其移向的右前方和中心区产生了强降水;垂直上升运动区及流线辐合区与暴雨落区有较好的对应关系;这次暴雨水汽输送源地有两个,分别是孟加拉湾和东海海面;水汽辐合区与暴雨落区相对应;垂直螺旋度的演变对本次西南涡暴雨有较好预报指示意义。

Diagnostic Analysis of Heavy Rainstorm in Henan Province From 12 to 15 July 2007

Base on the regular observational data and NCEP reanalysis data, a heavy rainstorm process occurred in Huang-huai region of Henan province from 12 to 14 July 2007 is diagnosed. The results show that the rainstorm is caused by a typical southwest low vortex when it moved to northeast, impacting Henan province. When the 500 hPa westerly trough moved to the east, its possession of cold air continuously intruded from northwest to southwest low vortex center, leading to the development of the southwest vortex eastward, shifting through Henan province. The heavy rainfall occurred in the right front and center of shifting movement. Vertical ascending motion area and the stream-line convergence zone and the rain fall area have more satisfactory correlation. The transfer of water vapor has two sources of the Bay of Bengal and the East China Sea. Moisture convergence zone is corresponded to the heavy rain fall area. The evolution of vertical helicity has a better forecast instruction significance to the southwest vortex rainstorm.