威海市冰雹天气气候特征

利用威海市1960年1月－1997年12月的的观测资料和灾情报告以及1986年1月－1995年12月的欧亚高空探测资料，分析了威海市冰雹的时空分布特征和天气气候特征。结果表明：威海市冰雹灾害的季节变化存在明显的双峰现象，春末夏初（5－6月）和夏末秋初（9－10月）次数最多，夏季较少。地理分布是半岛内陆多于沿海，西部多于东部。造成威海市冰雹的天气形势可分为低涡型、低槽型、西北气流小槽型和横槽型，其中以横槽型最少。各型冰雹天气中，山东半岛东部边界层有较强的暖湿平流，对流层中下部层结分布不稳定，湿区呈块状分布，范围较小，对流层中层是较强的干冷平流，对流层中上部是高空急流出口左侧的辐散区。

Climate Feature Analysis of Hail Weather in Weihai City,Shandong Province

The time and space distribution of hail storms in Weihai City are analyzed with observational data and catastrophic events report from January 1960 to December 1997 at sampling stations and sounding data from January 1986 to December 1995 in Europe and Asia.Results indicate that seasonal variation of the Weihai hail storms exist a double peak value phenomenon.Hail storms are the most in May,June,September and October.Synoptic situation of Weihai hail storms demarcated cold vortex type,trough type,small trough type in northwest air stream and latitudinal trough type.In hail area,there is strong warm humidity advection along the boundary.There is labile stratification under midtroposphere.The humid area is of pack shape and the dimension is small.There is strong dry cool advection in the midtroposphere.The divergence is at the left side of exit over the mid and upper troposphere.