内蒙古通辽市一次久旱转雨天气过程分析

Analysis of a Weather Process of Drouth Turning to Rain in Tongliao City of Inner Mongolia

利用常规观测资料、卫星云图、雷达回波等资料,对2009年4月18—21日内蒙古通辽市一次久旱转雨过程进行成因分析。结果表明,有利的大尺度环流、充足的水汽条件和较强的上升运动,同时低层有冷空气入侵激发该次降水的产生。降水是由于高空槽东移加强形成低涡、地面配合倒槽产生的。新一代天气雷达资料分析表明,回波具有明显的、典型的普雨降水系统特征。数值预报产品对这次过程的预报效果较好,深入数值预报产品的使用研究是提高重大天气预报质量的有效途径。

Based on the conventional observation data,satellite cloud images and radar echo data,the causes of a weather process of drouth turning to rain in Tongliao City of Inner Mongolia during April 18th～21st of 2009 were analyzed.The results showed that the advantageous large-scale circulation,ample vapor conditions,stronger ascending motion and cold air intrusion in low layers caused the occurrence of this rainfall.The eastward shift of upper trough reinforced to form the low vortex and inverted trough appeared on the ground,which led to the precipitation.The data analysis of new-generation weather radar showed that the echoes had obvious and typical characteristics of general rainfall.The forecast effects of using numerical forecast products on this process were better.Further application and research of numerical forecast products was an effective way to enhance the forecast quality of great weather processes.