不同天气系统影响下阵风锋的对比分析

Comparative analysis of gust front under the influence of different weather systems

利用常规观测资料、多普勒天气雷达资料和地面加密观测数据，对2014年6月8-9日发生在南宁的两次阵风锋天气进行分析。得到以下结论：阵风锋回波强度为10—20dBZ，水平尺度20km，呈弧状，成熟时高度大慨1．5km，阵风锋只是对流层低层的浅薄系统。阵风锋移动速度与母体雷暴移动速度的关系对雷暴的发展与减弱有很好的指示作用。阵风锋前沿有明显的风速辐合，可以触发新的对流单体的生成。两条阵风锋的相遇合并会使得阵风锋加强，更易触发新的对流单体产生。阵风锋愈强，其过境时所引起的风速增大的现象就愈明显。单体质心的快速下降和反射率因子核心的快速下降对地面雷暴大风有很好的指示作用，约可提前半小时预警。

Based on conventional observation data, Doppler weather radar data and ground observation data, two gust front weather processes during 8 to 9, June, 2014 in Nanning were analyzed. The results show that： gust front is just shallow system in the lower troposphere with 10 to 20 DBZ echo intensity, 20 km horizontal scale, arc shape and 1.5 km height when matured. The instructions of relationships between gust front moving speed and maternal thunderstorms moving speed performed well for the developing and weakening of thunderstorm. Obvious wind speed convergence in front of gust front triggers the generation of new convection cell. Furthermore, the new convection cell is more likely generated by stronger gust front, which was combined by two gust fronts trigger. The stronger gust front caused the more increase of wind speed. The rapid decline of monomer mass center and reflectivity core could be used for the half- hour early warning of the ground thunderstorm wind.