2019年6月上旬江西一次持续性暴雨天气过程成因

利用常规气象观测资料、FY-2G卫星TBB资料和NCEP/NCAR再分析资料，基于HYSPLIT模式，对2019年6月6—10日影响江西的一次持续性暴雨过程成因进行初步分析。结果表明： 1） 此次暴雨过程是一次大范围的持续性暴雨，产生于对流性不稳定环境场。暴雨区上空中层多短波槽活动，受槽后偏北气流影响，干冷空气叠加在低层暖湿气流之上，导致暴雨过程的发生。2） 暴雨落区主要位于低层850 hPa高度层的急流前端12—16 m/s的风速区内。3） 高空偏北气流的强弱在700 hPa高度层的风场和降水气块轨迹来源变化上有所体现。700 hPa高度层的假相当位温大于348 K的高温高湿区与正涡度区基本吻合，其位置对未来6 h的降水落区有一定的指示意义。

Analysis of the cause of a continuous rainstorm in Jiangxi in early June 2019

Using conventional observation data, FY-2G satellite TBB data, and NCEP/NCAR reanalysis data, the causes of a continuous heavy rain process affecting Jiangxi from June 6 to 10, 2019 were discussed based on the HYSPLIT model. The results showed that: 1) This rainstorm process was a large scale continuous rainstorm, generated in an unstable convective environment. Many short wave troughs are active in the middle layer, and affected by northerly airflow behind trough, dry and cold air is superimposed on the warm and humid airflow in the lower layer to produce torrential rain. 2) The rainstorm area was mainly located in the wind speed range of 12-16 m/s at the front of the 850 hPa jet stream. 3) The intensity of the high-altitude northerly air current was reflected in the changes of air mass trajectory for wind field and the source of the precipitation at 700 hPa. The 700 hPa pseudo-equivalent potential temperature greater than 348 K in the high temperature and humidity area was in good agreement with the positive vorticity region, and the location had certain indication significance for the precipitation area in the next 6 h.