2008年7月13日宁夏暴雨天气过程诊断分析

Diagnosis and analysis of rainstorm weather in Ningxia on July 13th,2008

利用常规天气图和物理量资料对2008年7月13日发生在宁夏的暴雨天气进行环流形势及物理量诊断分析.结果表明,此次过程是副热带高压西伸北抬,其边缘偏南气流与东移冷槽、低涡等配合造成的,其中由于有中小尺度系统发生发展,形成了局地性暴雨.这次暴雨无辐散层明显偏高,辐合值偏大;气旋深厚,范围大,强度强;低层能量值大,高层能量值小,降水时能量值有所增大,暴雨区与高能轴配合较好;水汽输送及辐合好,水汽输送主要集中在低层.

The atmosphere circulation and phystcat quantity 13th, 2008 were analyzed. The results showed that this process was coordinated by westward stretching and northward rising of subtropical high pressure with its southward airflow, eastward trough and low vortex. Because of the occurrence and development of the system in middle and small scale, a local rainstorm occurred. The characteristics of this rainstorm were higher level of no divergence, bigger convergence, deep and thick cyclone, large range and strong intensity. The energy in low level was bigger than that in high level and increased with the beginning of rainfall. The rainfall field was relatively consistent with high energy axis. A great deal of vapour was transported with bigger convergence. The vapour transporting concentrated mainly on the low level.