一次黑龙江省罕见阵风锋的生消史和天气特征分析

Analysis on the Birth and Disappearance History and Weather Characteristics of a Rare Gust Front in Heilongjiang Province

利用雷达、自动站和常规气象资料对2018年9月3日发生在黑龙江南部的一次飑线过程产生的阵风锋进行了分析。本次阵风锋天气特征表现为过境时明显的气压涌升、风速急增、风向突变,温度、湿度变化不明显。通过中尺度分析得出,上干冷下暖湿的环境提供了不稳定能量,配合强垂直风切变,中层干线、低空急流、地面辐合线、阵风锋提供了触发条件。通过雷达分析得出,发展成熟的阵风锋在飑线前沿表现为弧状“窄带回波”,其最前沿有辐合带,而在飑线单体中层有径向辐合带;阵风锋有利于飑线的移动和维持,一定程度上可以反映飑线主体的移动和变化。

The gust front generated by a squall line that occurred in southern Heilongjiang on September 3,2018 was analyzed using radar,automatic stations,and conventional meteorological data.The weather features of this gust front are obvious pressure surges,rapid wind speed increases,sudden changes in wind direction,and insignificant changes in temperature and humidity during the transit.Through mesoscale analysis,it is concluded that the upper dry and cold lower warm and humid environment provides unstable energy,with strong vertical wind shear,the mid-level trunk,low-level jet,ground convergence line,and gust front provide trigger conditions.According to radar analysis,the mature gust front appears as an arc-shaped"narrowband echo"at the front of the squall line,with a convergence zone at the forefront,and a radial convergence zone in the middle of the squall line;The gust front is conducive to the movement and maintenance of the squall line,and to a certain extent can reflect the movement and change of the main body of the squall line.