2015年5月16—17日粤西南沿海暴雨过程分析

Analysis of a Heavy Rain Process in the Coastal Area of Southwestern Guangdong May 16-17,2015

采用Micaps观测资料、NCEP再分析资料、中尺度自动站实测资料和雷达资料,通过对2015年5月16—17日粤西南沿海暴雨过程进行形势环境场、水汽、热力和动力物理量诊断分析。结果表明:有利的大尺度环流场为强降水的落区起到关键作用,副高西南部水汽输送为西南部大暴雨提供了充足水汽条件,同时能量锋为强降水提供了充足能量,在小槽波动、切变线南压和低层偏南气流的触发下造成了该次强降水。此外,地形增幅也是造成粤西南沿海大暴雨的一个原因。

With Micaps observational data, NCEP reanalysis data, mesoscale automatic weather stations data and radar data, we made a diagnostic analysis of the environmental field, water vapor, thermodynamic and dynamic physical quantities associated with a heavy rain process that took place in the coastal area of southwestern Guangdong on May 16 - 17, 2015. The result is shown as follows. A favorable large-scale circulation field is key to the area receiving the intense rain and the transport of water vapor from the southwestern part of a subtropical high provided sufficient amount of water vapor for the heavy rain in this part of the province. In the meantime, an energy front powered the intense rain, which had been triggered to happen due to the activity of minor westerly troughs, the southward progression of a shear and the presence of a lowlevel southerly flow. In addition, the terrain enhancement is also one of the causes for this heavy rain.