In this paper, the routine observational data, high resolution TBB data and NECP FNL reanalysis data were used to analyze a Meiyu front rainstorm process occurred during 14-15 June 2011, and the WRF model was used to simulate this process. The results showed that the rainstorm maintained over the northern part of Jiangxi due to the stable circulation situation and the continuous intersection between the cold air flow behind the 500 hPa trough and the strong southwest airflow. The trigger mechanism of rainstorm came from plentiful water supplement in low level, strong thermal instability, synoptic-scale and meso-scale convergences and terrain lifting. Frontal zone and its frontogenesis process were closely related to the occurrence of heavy rain. Positive vorticity developed upward along the frontal zone , which enhanced convective ascending motion and release of instable energy. Continuous southeast wind of low-level jet in the boundary layer provided the continuous water vapor. The short distance between high-low level jets was conducive to the development of vertical velocity and precipitation intensity.%利用常规气象观测资料、高时空分辨率TBB资料以及NCEP/FNL再分析资料，对2011年6月14—15日江西省北部梅雨锋暴雨过程进行了天气分析。同时，利用中尺度数值模式WRF对此次梅雨锋暴雨过程进行数值模拟，分析暴雨的中尺度系统结构特征。结果表明：稳定的环流形势下，500 hPa低槽后部冷空气与强盛的西南暖湿气流在江南北部持续对峙，使得暴雨区稳定维持在江西省北部。低层充沛的水汽供应、强的热力不稳定及强烈的天气尺度、中尺度辐合和地形抬升是此次暴雨产生的有利环境场和触发条件。锋区及其附近的锋生过程与强降水密切相关，冷暖气流在地面至对流层中低层的交馁，激发正涡度柱沿锋区倾斜爬升，强烈的上升气流穿越锋区激发大量不稳定能量释放。超低空急流的脉动和稳定维持为暴雨发生的有利水汽输送机制，高低空水平距离的缩短有利于高低空急流的耦合、垂直运动的发展和降水强度的加强。强降水区上空β中尺度对流扰动在冷、暖气流对峙区内不断生成、发展、东移，加之局地地形等作用致使大暴雨的发生。
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