冷涡背景下一次强雹暴过程雷达回波演变及降水谱特征分析OA

To gain a comprehensive understanding of the structural characteristics of typical hailstorm systems and the microphysical features of precipitation during different developmental stages,a detailed analysis was conducted on the echo evolution and precipitation spectral characteristics of a severe hailstorm process in Tianjin.This analysis utilized observational data from CINRAD/SA Doppler weather radar,laser disdrometers,and automatic weather stations.Results are as follows:(1)The convective storm experienced several developmental stages,including isolated cells,supercells,bow echoes and comma echoes.During the rapid development of the storm,the radar echoes exhibited characteristics such as three-body scatter spikes and sidelobe echoes.Additionally,weak echo regions and pendant structures were observed.The mid-level radial convergence feature was prominent.(2)The median volume diameter(D0)and the normalized Gamma distribution intercept parameter(Nw)showed inverse trends during precipitation.Under different rainfall intensity conditions,the distributions of raindrop spectrum parameters(lg Nw)and mass-weighted mean diameter(Dm)matched the typical characteristics of continental convective precipitation raindrop spectra.As rain intensity increased,Dm and lg Nw rose gradually,indicating a combined concentration-size control.The Liquid Water Content(LWC)increased with the enhancement of precipitation.When rainfall intensity exceeded 50 mm·h-1,the LWC was greater than 3.0 g·m-3.(3)During the maintenance stage of convective precipitation,small particles with diameters not exceeding 1.0 mm had high number density,which decreased sharply with increasing particle diameter.The raindrop spectrum had a peak particle size of 0.2-0.6 mm and a maximum width of 4-8 mm.At the strongest convection,the spectrum width was largest,with notable large and extra-large particles.As convection weakened,the spectrum width narrowed.