南疆2011年5月一次强冰雹天气的综合分析

 综合分析了2011年5月24日发生在南疆五团境内的一次强冰雹天气。结果表明,冰雹天气是在有利的天气背景下发生的,冰雹区上空的辐合上升运动为冰雹出现提供了动力抬升条件。L波段高空探测秒数据显示,雹暴发生前中低层风速明显增大并有暖平流。冰雹发生地存在层结不稳定和能量堆积。强雹暴的回波特点是,组合反射率因子CR长时间维持在50 dBZ以上,伴有弱回波区,液态水含量密度最高达4.0 g·m-3,垂直高度接近12 km。

Comprehensive Analysis of a Severe Hail Event in May, 2011 in Southern Xinjiang

Storm weather is often accompanied by severe hails and other severe convective weather,but the forecast of severe hail is a difficult problem.For the purpose of increasing the forecasting ability of severe hail weather,we analyzed a severe hail process occurring on 24 May,2011 in southern Xinjiang.Results showed that the convergence ascending motion over the region provided favorable dynamic uplifting condition for the occurrence of the severe hail.The upper-air second-interval observation datasets at L wave band showed the wind velocity increased and the warm advection existed in both low-level and middle-level atmosphere.There were local unstable stratification and energy accumulation in the area.The main echo features of the severe hail are as follows: long-term persistence of composite reflectivity greater than 50 dBZ,companied with a weak-echo region,the vertically integrated liquid density reached 4.0 g·m-3,and the echo top of vertically integrated liquid density at about 12 km.