为了研究强对流天气和暴雨形成演变机理，提高暴雨预警能力，利用欧洲中心 ERA - interim 再分析资料、L 波段探空秒级数据、SA 雷达数据等多信息源资料，对华南暴雨典型个例进行了综合分析。结果表明：暴雨区的风向从地面到高层随高度顺转；暴雨区对流抑制能量很小，抬升凝结高度很低，只需要一点抬升作用就可触发对流；对流强盛阶段，呈现出明显的雷达回波火车列形态，并沿700 hPa 引导气流向东北方向移动。在降水前，700 hPa 整个降水区域空气相对湿度超过70％，并在925 hPa 出现相当位温大值区，这些在降水前就出现的指标对强降水预报具有重要指示意义。%By using the multiple sources of information,including the European Centre Re - Analysis data(ERA - Interim), the L - band second - level sounding data and the SA - RADER data,we analyzed the typical heavy rainfall cases in South China to research the formation and evolution mechanism of heavy - rain - producing and intense convective systems and improve the rainstorm pre - warning ability. The research shows that the wind direction in heavy rainfall area turnes clockwise as the altitude increases;CIN over the area was very little,and LCL was very low,meaning that a little updraft could trigger convection. During the convective stormˊs mature stage,an obvious echo - training pattern is observed with convective cells moved northeast along the 700hPa steering airflow. Before the rainfall,the relative humidity in 700 hPa precipitation area exceeds 70% ,and θe reaches high value area in 925hPa area. These indexes in advance of a rainfall event show great forecasting significance.
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