一次特大暴雨过程中涡度与急流的影响分析

利用自动气象站雨量资料,常规观测资料,FY-2D TBB云图资料以及NCEP再分析资料,对2013年6月30日～7月2日高原低涡东移和西南涡耦合形成的遂宁地区特大暴雨过程进行研究。主要分析了高原低涡和西南涡的耦合对此次强降水的影响以及低空急流演化和强降水的关系。结果表明:当高原涡和西南涡发生耦合时会使得高空低涡发展加强,并激发遂宁暴雨天气的产生。急流为高空低涡的发展提供不稳定能量。超低空急流和低空急流对强降水有提前2小时的指示意义,低空急流指数增大的过程和降水量的强度成正比关系。 

Analysis for Effects of Vortex and Jet Stream during a Rainstorm

Based on the rain gauge data at automatic weather stations,conventional observations,FY- 2D TBB satellite pictures and NCEP analysis data,the rainstorm in Suining city caused by the coupling interaction between Plateau and southwest vortexes from 30 Jun to 2 July in 2013 were analyzed. In this paper main analyzed the coupling interaction between Plateau and southwest vortexes impact on the heavy rain and evolution of the Low- level jet and Its relationship with the heavy rainfall.The results show that the altitude vortex development to strengthen when the coupling interaction between Plateau and southwest vortexes and stimulate the production of heavy rain in Suining city. Jet provided energy for the development of altitude vortex.Low altitude jet and low- level jet will not certainly immediately cause a strong rainfall,sometimes this process will be delayed two hours. The degree of increase in the low- level jet index(I) and the intensity of rainfall have a direct proportional relationship.