Using the conventional observation data from February to March from 2005 to 2014,the characteristics of temporal and spatial distribution,system configuration,as well as the ambient field of elevated thunderstorm hail in the western Hunan are analyzed.Results reveals that hails occur more frequently in the south than in the north and middle areas in the concerning area with a diurnal variation.The main influencing weather systems include upper-level through,low level jet (LLJ) in 700 hPa and cold air,etc.Indicators of potential forecast of the elevated thunderstorm hails are as follows:relative humidity greater than or equal to 92％ at 850 hPa,60％ at 700 hPa,but smaller than or equal to 48.5％oo at 500 hPa;thermal front at 850 hPa with a threshold temperature difference of 13 ℃ per 5° of latitude;temperature difference between 700 hPa and 500 hPa greater than 15 ℃;wind speed of LLJ at 700 hPa greater than 16 m.s-1;vertical wind shear between 850 hPa and 700 hPa greater than 19 m.s-1;the height of 0 ℃ levellower than 3 to 4 km;and the height of-20 ℃ level between 6 to 7 km.%利用常规气象观测资料,对2005-2014年湖南省湘西州2-3月高架雷暴类冰雹的时空分布特征、天气系统配置及环境场要素特征等进行统计分析,探讨高架雷暴类冰雹发生发展的物理机制.结果表明,湘西早春时期的高架雷暴类冰雹南部地区多于中北部地区,具有一定的日变化.影响高架雷暴类冰雹的主要天气系统为高空槽、700 hPa急流以及冷空气等.潜势预报指标包括:850 hPa相对湿度大于等于92％,700 hPa相对湿度大于等于60％,500 hPa相对湿度小于等于48.5％;850 hPa存在强的温度锋区,温差大于等于13℃／5个纬度;700 hPa与500 hPa的温差大于等于15℃;700 hPa有风速大于等于16m·s 1的西南急流,且850 hPa与700 hPa的垂直风切变大于等于19 m·s-1;0℃层高度为3～4 km,-20℃层高度为6～7 km.
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