利用常规观测资料、卫星云图和地面加密观测资料以及NCEP再分析资料等，对2013年6月26-29日江西持续暴雨过程进行天气动力学诊断分析和中尺度分析。结果表明：(1)此次持续暴雨过程是西太平洋副热带高压、季风涌、冷空气以及青藏高原东传的短波槽共同作用的结果；(2)对流层低层水汽辐合加强，以及低层辐合和高层辐散使垂直运动厚度和强度增大，有利暴雨强度增强；(3)冷暖交汇区上升支气流与其北侧的下沉气流同时加强，也有利于暴雨增强；(4)对流层低层西南急流的日变化与强降水在后半夜至凌晨开始加强关系密切；(5)该过程伴随着一系列γ或β中尺度对流系统发生、发展、合并，导致了赣北地区持续暴雨或大暴雨；(6)中尺度强雨团有向地面辐合线区域和对流性不稳定大值区移动发展的趋向。%Dynamic diagnosis and mesoscale analysis to a sustained rainstorm event happened in Jiangxi from June 26 to 29, 2013 was per-formed using data from conventional observations, satellite images, the intensive observations from automatic weather station and NCEP re-analysis. The results indicate that this sustained rainstorm event is caused by the interaction among the West Pacific subtropical high, mon-soon surge, cold air and shortwave trough from Qinghai-Tibet Plateau. The increase in strength and thickness of vertical movement due to strengthened vapor convergence in the lower troposphere, convergence in the low-level and divergence in the upper level is favorable to the strengthening of the rainstorm. In addition, another favorable factor is the simultaneous strengthening of the ascending branch airflow over in-tersection of cold and warm air masses and the sinking branch airflow over north side of the intersection. Diurnal variation of southwesterly jet in lower troposphere is closely related to the strengthening of heavy rainfall beginning by midnight. The genesis, development and merging of a series of meso-γ-scale or meso-β-scale convective systems lead to the continuous rainstorm or extra heavy rainstorm in the northern Ji-angxi. Strong mesoscale rain clusters tend to move towards the ground convergence line and the large convective instability zone.
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