2019年4月山西南部一次强对流天气过程分析

Analysis of a severe convective weather process in southern Shanxi in April 2019

根据micaps常规资料,地面加密观测资料、多普勒雷达资料,详细分析了2019年4月24日山西南部产生的一次大范围强对流天气的成因和触发机制,其冰雹、雷暴大风强对流天气过程是在高空槽、低层切变线、低涡共同影响下,由低层切变线和地面中尺度辐合线共同触发的一次飑线过程。飑线过程雷达资料表明:地面中尺度辐合线对弓形回波的发展加强有促进作用;VIL跃增对冰雹有一定的指示意义,可以提前1~2个体扫;强回波质心的不断下降和VIL快速减小对雷暴大风预报有一定指示意义,可以提前2~3个体扫。

Based on the conventional MICAPS data,ground intensive observation data and Doppler radar data,the causes and trigger mechanism of a large-scale severe convective weather in southern Shanxi Province on April 24,2019 are analyzed in detail.Under the influence of high-level trough,low-level shear line and low-level vortex,the severe convective weather process of Hail and thunderstorm is affected by the low-level shear line and surface mesoscale convergence line A squall line process triggered jointly.The radar data of the squall line process show that:the surface mesoscale convergence line can promote the development and strengthening of bow echo;VIL jump has a certain indication significance for hail,which can be swept 1-2 individuals in advance;the continuous decline of the centroid of strong echo and the rapid decrease of VIL have certain indication significance for thunderstorm gale forecast,which can be scanned 2-3 individuals in advance.