陕南东部一次短时强降水天气的成因分析  

Analysis of very short-range severe precipitation in east of southern Shanxi province

作　　者：徐娟娟[1] 郝丽 屈丽玮[1] 胡启元[1] XU Juanjuan;HAO Li;QU Liwei;HU Qiyuan(Shaanxi Meteorological Observatory,Xi’an 710016,China;Shaanxi Climate Center,Xi’an 710016,China)

机构地区：[1]陕西省气象台,陕西西安710016 [2]陕西省气候中心,陕西西安710016

出　　处：《中低纬山地气象》2019年第1期9-14,共6页Mid-low Latitude Mountain Meteorology

摘　　要：利用常规高低空气象观测资料、地面逐小时降水、物理量和卫星云图资料,对2017年4月15日发生在安康东部的一次局地短时强降水天气进行诊断分析,结果表明:西风带的中层弱冷空气与安康附近的东南暖湿气流交汇时,触发对流产生;低层850 hPa东南气流为局地短时强降水提供了比较充沛的水汽;大气低层存在大量不稳定能量;高空300 hPa的较强辐散与低层850 hPa较强辐合叠加,提供了较强的上升运动;在卫星云图上表现为一个水平尺度为100～200 km,云顶亮温TBB最低为-56℃,生命史为10 h的中-β尺度对流云团。Using the routine upper and low level meteorological observation data, hourly precipitation,physical quantity and satellite nephogram data,a local short-term strong precipitation occurred in Easten part of Ankang city on 15 April 2017 was analyzed. The results show that the convection appeared when the weak cold air of westerlies met the Southeast warm moist air flow of Ankang;The low-level southeast air flow on 850 hPa provid the plentiful water vapor for the local short-term strong precipitation;A vast amount of unstable energy exist in the Lower Atmosphere;The superposition of the stronger divergence on high altitude 300 hPa and the stronger convergent on low layer 850 hPa supplied a powerful updraft;There is a meso-β-scale convective cloud cluster with horizontal scale of 100~200 km in satellite cloud image,which the lowest black body temperature (TBB) reaches to -56 ℃,and lasts for 10 hours.

关 键 词：短时强降水 弱冷空气 比较充沛的水汽 不稳定能量 中-β尺度对流云团 

分 类 号：P458.121[天文地球—大气科学及气象学]