三门峡市一次飑线过程的诊断分析

Diagnostic Analysisof a Squall Line Process in Sanmenxia

本文利用高空、地面观测资料、NCEP6h一次的1°×1°再分析资料和多普勒雷达资料,对三门峡市2016年6月5日的一次飑线天气过程进行分析。结果表明:此次飑线过程是在高空西北气流背景下产生的,850hPa的低涡和地面辐合线提供了抬升触发条件;热力不稳定度和垂直风切变的加大是导致对流强度增强的主要原因;地形的辐合抬升作用,增强了雷暴单体的发展强度,对飑线的增强及有组织性起到重要作用;低层正负速度大值中心可以很好地指示地面大风。

In this paper,a Squall Line Weather Process in Sanmenxia City on June 5,2016 was analyzed by using high altitude,ground observation data,NCEP6h reanalysis data and Doppler radar data.The results showed that the squall line process was generated under the background of Northwest Airflow at high altitude,and 850hPa low eddy and ground convergence line provided lifting trigger conditions;the increase of thermal instability and vertical wind shear was the main reason for the enhancement of convection intensity;the convergence and lifting of terrain enhanced the development intensity of thunderstorm monomer,and played an important role in the enhancement and organization of squall line.The center of high positive and negative velocity at low level could well indicate the strong wind on the ground.