基于相控阵雷达的浙江风雹过程天气动力和微物理特征分析OA

In order to study the dynamic and microphysical characteristics of wind and hail events in Zhejiang using phased array dual polarization radar,an analysis of the wind and hail event in Zhejiang on 10 July 2023 was conducted based on X-band phased array radar observation data,wind field reversal,particle recognition and other products.The results indicated that the storm occurred in an environment characterized by high energy,vertical instability,and weak vertical wind shear.Hail storm was stronger than extreme wind storm,which developed at higher altitudes,and exhibited a backward-propagating storm pattern.During the hail event,the mass center of the horizontally polarized reflectivity factor(ZH)and differential phase shift(KDP)sank,while the low-level differential reflectivity(ZDR)decreased.The region of low correlation coefficient(CC)first extended upwards before sinking as the ice crystal particles and supercooled water drops fell from the layer above 0℃,reaching the ground as rain and hail.Extreme gale storm developed in a basin,with the terrain convergence enhancing its intensity.As the extreme wind approached,the center of mass for ZH and KDP rapidly dropped to the near-surface and falling precipitation particles strengthened the downward airflow through entrainment.Besides,the horizontal contraction and vertical stretching of the radial convergence velocity in the middle layer,along with the divergence velocity near the surface indicated the occurrence of localized downburst.Meanwhile,the downslope terrain and the basin venturi effect further accelerated the near-surface winds.