一次暖区强降水的热动力条件分析

Analysis of Thermodynamic Conditions of A Heavy Rainfall in Warm Sector

本文利用地面自动站观测资料、雷达资料和NCEP再分析资料，分析了2009年4月19日福建中南部强降水过程的热动力条件，分析结果表明：这次降水过程具有明显的中尺度雨团活动，直接影响系统是地面中尺度辐合线；低空西南急流为暖区强对流发生、发展提供了必要的水汽条件；而低层暖平流、高层冷平流的上下层配置，使不稳定能量得以积聚，为对流发展提供必要的能量。

By using the data from the automatic ground station, radar and NCEP reanalysis, the cause and thermodynamic conditions of a heavy rainfall in central and southern Fujian On April 19, 2009 were analyzed. The results show that： This process has active mesoscale rain band. The mesoscale convergence zone at ground is a direct system of influence. Southwest low-level jet provided the water vapor for the occurrence and development of strong convective in warm sector. The low-level warm air advection and high-level cold air advection build the unstable energy, and provide the necessary energy for convection development. Because of the geographical terrain specificity of Fujian, a strong southerly wind makes the rainfall increase obviously on the coastal areas.