摘要
利用多部新一代天气雷达资料结合常规探空资料和逐小时的自动站资料,对2007年7月18日发生在河北省东部平原(以下简称冀东平原)的一次区域性暴雨过程进行分析。结果发现:低层中α尺度切变线的南压、东移及"人"字形辐合线是本次降水过程的主要影响系统;降水发生前西南暖湿气流和冀东平原近地层偏东风是"人"字形辐合线形成的直接原因;在不稳定层结存续条件下,急流方向上上游雷达站中尺度低空急流的脉动对下游台站的短时暴雨预报具有一定时效的指示意义。
Based on the Doppler radar echo data and conventional sounding data as well as hourly rainfall data, a regional heavy rain event occurred in eastern Hebei plain on July 18, 2007 is analyzed. The results show that the southward and eastward moving of a meso-a-scale shear over low-level and the convergence line are the main influential systems. The convergence line is caused by both the maintaining southwest-moist-jet before the rainfall and the surface layer easterly airflow over eastern Hebei plain. Under the unstable stratification condition, the perturbation of meso-scale low-level jet of upstream radar stations is of significance for downstream stations＇ rainfall forecasting.
出处
《灾害学》
CSCD
2010年第1期64-68,共5页
Journal of Catastrophology
基金
河北省气象局科研基金项目资助(2008ky20)
关键词
雷达回波
大暴雨
应用分析
冀东平原
radar echo
rainstorm
application analysis
eastern Hebei plain
