东莞一次短时强降水过程的多种资料特征  

Multiple Characteristics of Data for a Short-Range Intensive Rain in Dongguang

作　　者：张劲梅 ZHANG Jing-mei(Meteorological Bureau of Dongguan City, Dongguan 52300)

机构地区：[1]东莞市气象局,广东东莞523000

出　　处：《广东气象》2017年第2期17-21,共5页Guangdong Meteorology

摘　　要：利用常规、非常规观测资料及灾害天气短时临近预报系统产品,对2015年9月7日上午发生在东莞的一次短时强降水过程进行分析。结果表明:(1)该次短时强降水是高空槽后偏西北气流引导低层弱冷空气南下,在华南强不稳定层结环境下,边界层弱冷空气诱发中尺度切变辐合抬升加强,触发高能高湿区能量释放,产生强降水;水汽来源主要为超低空及地面边界层。(2)Swan系统平台区域自动站网实时风演变能有效分析中、小尺度天气系统的短时发展,对短时临近预警有较好的指示性;1 h预估降水量(QPF1)与实况比较接近,对降水临近定量预报有较好参考作用;垂直液态含水量(VIL)值较低,降水次效率高,以强降水为主的对流天气。(3)垂直风廓线、GPS可降水量(PWV)在强降水产生前4~6 h都有明显的变化,对临近预警有较好的指示性。Conventional and non-conventional observations as well as nowcasting products are used to study a short-range intense rain that took place in Dongguan in the morning of September 7, 2015. The re- sult is shown as follows. （ 1 ） The rain was caused as low-level weak cold air was steered by a northwesterly flow at the rear of an upper-level trough, in combination with highly instable stratification, strengthening of a mesoscale shear due to convergence and uplifting that resulted from the mildly cold air in the boundary layer. The water vapor mainly came from the ultra-low level and surface boundary layer. （2） Real-time wind evo- lution of the Swan regional automatic stations network can effectively study the short-range development of meso- and fine-scale weather systems, a good indicator for nowcasting. As 1 -h quantitative precipitation fore- cast （QPF1） is close to the observation, it is useful in quantitative nowcasting of rainfall. In this case, the vertically integrated liquid （VIL） water content is relatively low but precipitation efficiency is relatively high, suggesting a convection weather that is mainly composed of intense rain. （3） Significant changes were recorded in both the vertical wind profiles and GPS-based precipitable water vapor （PWV） 4 to 6 h prior to the intense rain, serving as a good indicator in nowcasting.

关 键 词：天气学 短时强降水 预估降水 垂直液态含水量 风廓线 东莞市 

分 类 号：P44[天文地球—大气科学及气象学]