中文摘要：

利用2009年东北暴雨试验资料、常规气象观测资料、自动站资料、FY-2C卫星资料和NCEP再分析资料,对2009年6月19日东北地区一次短时强降水过程的天气尺度环流特征、中尺度对流系统（MCS）环境场及其触发机制进行了分析,概括了此次冷涡发展阶段暴雨过程的三维概念模型。结果表明,此次强降水系统主要发生在东北冷涡的发展阶段,造成强对流天气的系统尺度较小、突发性强,具有明显的β-γ中尺度对流系统的特点。高温高湿及位势不稳定层结、低层的湿舌北伸及中层干冷空气的侵入,为MCS的发生、发展提供了非常有利的环境条件。位于高空西风急流出口区北侧和偏东北大风中心入口区南侧的暴雨区上层有强的高空辐散,与辐合区南侧的低空急流前部相互耦合,使得暴雨区上升气流增强;高空急流出口区南侧的偏南风低空急流加强了风暴的入流强度,为风暴提供了有利的风场环境和水汽条件。暴雨区西南侧中低层存在干空气侵入,使中低层干冷空气迅速向对流风暴发生区输送,形成逆温层。在强对流爆发前,中低层的逆温层与上层的干层分开,使风暴发展所需的不稳定能量得以累积,冷涡系统东移引导低层偏西北气流南下,增强了地面流场的辐合,是触发初始对流的关键因素。

英文摘要：

Using the observation data of Northeastern China heavy rainstorm experiment in 2009, con- ventional observation data from meteorological observation, automatic weather station, FY-2C satellite and NCEP reanalysis data, synoptic scale characteristic, mesoscale convective system and severe convective trigger mechanism of mesoscale convective system during a heavy rainstorm process in Northeastern China on 19 June 2009 are analyzed and a three-dimension concept model of the rainstorm process during the development of the cold vortex is summarized. The results show that, the heavy rainfall mainly happened in the development state of the cold vortex, and there were small scale, suddenness features, which with typical mesoβ-γ scale characteristics. High temperature, high relative humidity, geopotential unstable lay- er and high vapor tongue stretched toward the northwest in the low level and the dry air incursion in the middle level provide the extraordinary favorable environment condition for the development of the convective system. The configuration of the two upper level jets intensifys the divergence above the convective area, coupling with the ahead of the lower level jets on the south side of convergence zone, which strengthens the rising stream of the storm. Sountherly lower level jet of exit region on the south side of upper level jet enhances the inflow intensity of storm which provide the plenty of vapor for the convective systems. The dry air incursion of middle level of western rainstorm make the cold dry air to be rapidly trans port the convective strom occurrence area, which leads to thermo-inversion layer. Before the convective system happened, the thermo-inversion layer of middle and lower levels the dry layer of upper level is separated, which accumulates the unstable energy of the storm. The low level northwest horizon wind strengthens the convergence of surface stream field, which is the key factor of initial convective systems.