利用降水资料、卫星资料、NCEP再分析资料、韩国天气图资料以及探空资料,从天气形势、中尺度特征和环境场特征等方面分析了2014年8月31日发生在重庆的一次特大暴雨过程。结果表明,高、低空急流、切变线、地面冷高压共同作用导致了暴雨发生；MCS是降水的直接影响系统,MCS的发展演变对于预报暴雨的强度和落区具有良好的指示意义；探空资料计算的对流指数对对流过程的发生演变有一定的指示意义,大气在垂直方向上上冷下暖、上干下湿的配置结构有利于对流性不稳定的增强；副高外围暖湿空气是输送暖平流的主要物理机制；强降水发生于MPV1等值线零线和MPV2强负值中心南侧等值线密集区附近,对应对流不稳定和斜压不稳定的叠置区域；MPV1零线对于降水的预报有一定的指示意义,MPV2负值区与辐合区紧密联系。%Using precipitation data, satellite data,NCEP reanalysis data, Korea Meteorological Administration data, sounding data, the ex-treme torrential rain in Chongqing on 31 August 2014 was analyzed from aspects of weather situation, mesoscale feature and environment field feature. The results indicated that the rainstorm is the result of high-level jet, low-level jet, shear line and surface cold high pressure;MCS is the direct influence system of this precipitation, the development of which has indication significance on forecasting the intensity and area of heavy rainfall;convective index indicates the evolution of the strong convective storm, temperature and humidity field presents‘cold and dry in high-level, warm and moist in low-level’ in vertical direction, convective instability get much stronger;warm advection is transported by the warm moist air of tropical pressure periphery, cold advection is transported by the cold air in the northward path that lies at the front of the high-pressure ridge near 102°Eand eastward path that lies at the bottom of the cold anticyclone near Shandong;heavy rainfall occurred in the zero line of MPV1 and the dense isoline region nearthe negative center of MPV2, which is corresponding to the junction of convective instability and baroclinic instability;the zero isoline of MPV1 has indication significance on heavy rainfallforecasting, there is close connection between the negative center of MPV2 and the convergence zone.
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