2010年5月31日至6月1日华南特大暴雨过程经历了三次集中降水期，共有4次MCS（Mesoscale Convective Systems）演变过程，其中一个TL/AS MCS（Training Line/Adjoining Stratiform Mesoscale Convective System，邻接层状单向发展的中尺度对流系统）在广西壮族自治区中部准静止地维持了10多个小时，导致了多个观测站出现极端强降水。用观测资料和数值模拟结果重点探讨了该TL/AS MCS的观测特征及其发展持续的环境条件。结果表明，准静止TL/AS MCS发展在一个高空强辐散、低空气旋性汇合环流的天气尺度环境中，TL/AS MCS维持期间热力环境特征表现为对流层中低层持续高湿近饱和态、偏中性层结、合适的对流有效位能和极小的对流抑制能量。在对流层中低层，低空急流的加强发展维持与对流层中层相对弱的环境风形成了风垂直切变随高度呈现强逆转，近地层风垂直切变垂直于对流线的分量大，而在中层风垂直切变平行于对流线的分量占绝对优势，风切变特征可能是TL/AS MCS 准静止的原因；低空急流和中层环流的相互作用、对流层动力和热力条件有利于强上升运动的长时间维持与发展，不断触发新对流从而组织成一个长生命期准静止的TL/AS MCS
During May 31 to June 1, 2010, an extraordinary rainstorm process occurring in southern China included three concentrated precipitation periods and approximately four times the normal mesoscale convective system (MCS) activities. Among them, a quasi-stationary training line/adjoining stratiform (TL/AS) MCS was maintained for more than 10 h in central Guangxi Zhuang Autonomous Region, resulting in extreme precipitation events recorded by multiple stations. Using observation data and simulated results, the observation characteristics and continuing environmental conditions of this system were analyzed in this study. The results showed that the quasi-stationary TL/AS MCS was developed in an upper divergence and mid-lower cyclonic circulation environment. The MCSs forming in thermodynamic environments were characterized by very high relative humidity at low levels, moderate convective available potential energy, and very little convective inhibition. The presence of a strong low-level jet (LLJ) and weak midlevel winds led to a pronounced reversal of the wind shear vector with height. The vertical wind shears were largely perpendicular to the convection line at low levels, but were mainly parallel to the line at mid-levels. These wind shear characteristics may have caused the TL/AS MCS to become quasi-stationary. The lifting and destabilization associated with interaction between the LLJ and midlevel circulation assisted in initiating and maintaining the long-lived, slow-moving MCSs.
王晓芳,赖安伟,王志斌.一个长生命期准静止中尺度对流系统的观测特征及其持续的环境条件.大气科学,2014,38(3):421~437 Wang Xiaofang, Lai Anwei, Wang Zhibin. Observation Characteristics and Continuing Environmental Conditions for Long-Lived and Quasi-Stationary MCS. Chinese Journal of Atmospheric Sciences (in Chinese),2014,38(3):421~437复制