强热带风暴“天鹅”小波动路径原因分析

Analysis of the Causes for Slight Route Fluctuation of the Strong Tropical Storm ′KONI′

利用常规资料、卫星云图和雷达回波资料分析了引起0308号强热带风暴"天鹅"移动过程中在海南岛内出现小波动的原因。结果表明:"天鹅"转向的环流背景是副高加强西伸和高空急流建立;地面中小尺度低涡和切变线的存在与变化是导致"天鹅"小波动路径的重要因素,台风有向着三小时最大负变压区移动的趋势;雷达回波和卫星云图中云型的演变为"天鹅"小波动路径提供依据。

Analyzes the causes for the slight route fluctuation of the No. 0308 strong tropical storm ′KONI′ during its movement in Hainan island. It shows that the strengthening westwards stretching of the sub-high pressure and the establishment of upper jet stream forms the circumfluence background, while the existence and change of the ground medium-small sized low vortex and shear line make the main contribution to the direction turning of the ′KONI′, leading the typhoon towards the 3-hour maximum negative pressure change area. The radar back wave and evolution of cloud types in satellite nephogram provides the basis for the slight fluctuating route of the ′KONI′.