“碧利斯”的中尺度雨团和雷达回波分析

Analysis between Radar Echoes and Mesoscale Rainstorm of "Billis" Typhoon

对“碧利斯”雷达回波分析表明:雷达回波受着三个阶段不同天气尺度的影响。第一阶段是台风低压强偏北气流的作用,强中尺度雨团出现在强风的左侧;第二阶段是台风辐合线与西南急流的共同作用,强中尺度雨团出现在西南急流左侧辐合线辐合最强的地方;第三阶段是台风低压过境时北侧强旋转风的作用,强中尺度雨团出现在东南急流与东北急流间气旋性曲率最大的地方。三个阶段的回波性质不尽相同,降水性质也差别很大。对这三个阶段主要的雷达资料进行分析研究,总结出一些规律性结论,有益于今后在雷达回波监测网中熟练掌握不同天气尺度的雷达回波中中尺度雨团的发生发展,使其在短时临近预报、联防预警信息及预警信号的发布中起到重要作用。

Based on the analyzing on radar echo, results indicate that it is divided three stages synoptic scales that effect on the radar echo. The strong rainstorm occurred on the left side of the strong wind in the role of the north stream of the typhoon low in the first stage. The interaction of the southwest jet and the convergence line of Billis make the rainstorm taking piace in the region that is the left of the southwest jet with the strong convergence in the second stage. In the third stage rainstorm developed in the place where the cyclone curvature between the southeast and northeast wind is the biggest because of the strong revolving wind of the passing typhoon low. Such regularity conclusion given out is benefited for the forecaster to grasp the rule of different characters of meso-scale rainstorm with different synoptic scales and those characters can provide some valuable references to monitor and warning the now-casting weather and issue warning signal.