初春暴雪过程的多普勒速度特征分析

Analysis of Doppler Velocity Feature on Snowstorm of Earlier Spring

利用多普勒雷达资料对烟台市一次初春暴雪天气的多普勒速度和风场结构特征进行了分析。结果表明:降雪开始后相继出现的暖平流辐合、闭合零速度区和逆风区是本次暴雪天气过程多普勒速度的主要特征;持续的垂直风向切变及强辐合等风场结构为暴雪产生创造了条件;低空东南气流对多普勒速度特征的形成及暴雪的产生起了主导作用。

The paper analyses the evolution of Doppler velocity and the structure of the wind field during a infrequent snowstorm of earlier spring taken place in Yantai by using Doppler radial products. Results show that the warm advection convergence, close zero velocity field and adverse wind area which appear successively during the snowstorm are the main character of Doppler velocity. The special structure of wind area such as continuous vertical wind direction shear and the strong convergence create the useful situation of the snowstorm.The south-east wind current have a leading influence on the form of Doppler velocity feature and the creation of snowstorm.