中文摘要：

使用常规天气资料、卫星云图和长春C波段多普勒雷达资料对2004年7月5日发生在吉林省的一次典型台风外围雨带降水天气过程进行了分析。可看出两种尺度云系的相互作用，整个降水雨带为明显的旋转西进过程。多普勒径向速度图上，低层辐合高层辐散的配置有利于降水的发生发展。另外，低层由于存在摩擦，受台风雨带影响较小，而中高层受台风中α尺度系统和中β尺度雨团的共同影响，两者风场的叠加造成低层偏东风到高层东北风的风向变化。可提高预报的准确率，为人工增雨决策提供可靠依据。

英文摘要：

This typical precipitation which took place in the spiral rain band of a typhoon on July 5, 2004 in Jilin province was analyzed by using conventional weather data, satellite cloud images and 5 cm Doppler radar in Changchun. We can see the interaction between two cloud systems of different scales and the obvious process of the whole rain band that eireumvolves moves towards the west. And on Doppler radial velocity images, the configuration of low level convergence and high level divergence is propitious to happening and developing of precipitation. Besides, the low level impact of typhoon＇ s rain band is small owing to the friction, while at the middle and high levels due to combination of impacts induced by of typhoon meso-α scale rain system and meso-β scale rain clusters, the superposition of two wind fields causes the change of wind direction from east at the low level to northeast at the middle and high levels. It can provide reliable basis for improving forecast accuracy and the decision-making of precipitation enhancement.