使用探空观测资料、NCEP再分析资料及多普勒天气雷达产品等多种气象资料,对2015年4月3日湖南出现的一次大范围不同类型强对流天气过程进行了分析,结果表明:强对流天气过程发生前大气环流出现明显调整;低空西南急流的发展加强、中层干冷空气的卷入为大范围强对流天气提供了有利的环境条件;高层辐散、低层辐合的抽吸作用及气旋性切变、湿斜压强迫作用,是湘东北发生混合对流和极端强降水的主要原因.汉寿在逆温层之上暖湿气流抬升和强垂直风切变作用下产生的冰雹,具有高架雷暴特征.新晃具有较高热力不稳定,在冷暖空气交汇时产生冰雹.雷达产品分析表明,冰雹、雷雨大风发生时分别具有典型的三体散射与中高层较强辐散特征,而短时强降水发生时具有低质心和高效降水效率及列车效应特征.%A widespread convection event with multiple convection types is analyzed by using sounding observation data , NCEP reanalysis data and Doppler weather radar products, which occurred in Hunan province on 3rd April 2015. The results are shown as follows. Atmospher-ic circulation had clear adjustment before the occurrence of strong convection weather event. Strengthening of the low level southwest jet and involvement of cold dry air in middle layer provide favorable environmental conditions for the convective weather. Suction effect of upper-lev-el divergence and low-level convergence, as well as the cyclonic shear and wet baroclinic forcing effects are the main reasons for mixed con-vection and extreme precipitation in northeast Hunan province. Caused by the combined effect of warm and wet air being uplifted above inver-sion layer and strong vertical wind shear, hailstones appear in Hanshou station, which have the elevated thunderstorm characteristic. Due to the high thermal instability in Xinhuang, hailstones occur frequently in the intersection of cold and warm air. Radar product analysis shows that hail and thunderstorm winds are charactered by typical three-body scattering and middle strong high-level divergence, while short-time rain storm is charactered by low-centroid high efficient precipitation and train effect.
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