利用2000-2014年6-8月常规资料、FNL资料和辽宁省逐时降水资料,将东北冷涡分为北涡、中间涡和南涡,统计每类冷涡短时强降水特征,并进行动态合成分析.结果表明:短时强降水共755次,冷涡下227次,冷涡强降水多发生在1～3h内.6月短时强降水主要由中间涡引起,7、8月中间涡与北涡共同影响,有一定周期变化;而南涡没有在辽宁产生强降水.北涡水汽输送充沛,中间涡水汽条件较差,切变辐合场与水汽输送的结合是有利于强降水的重要因子.降水基本处于斜压区内,冷涡中心降水处在斜压区北侧和高空急流左前方,高空槽前或槽后的降水处在斜压区南侧和急流中心右后方,降水区附近多有高空急流形成的次级环流配合.槽后降水区干侵入活动明显,冷涡中心降水主要通过高位涡诱发气旋性环流而触发上升运动.%By using the conventional data,FNL data and hourly precipitation data in Liaoning province from June to August during 2000-2014,the Northeast China Cold Vortex(NCCV) was divided into north vortex,middle vortex,and south vortex,and the short-time heavy rainfall characteristics of each cold vortex were statistically studied and dynamically analyzed.Results show that there were 755 times of short-time heavy rainfalls,only 227 times happened under the background of NCCV during 1 to 3 hours.Steered most by middle vortex in June,heavy rainfall is collectively affected by both middle vortex and north vortex in July and August with a certain periodic variation.Moreover,north vortex has abundant moisture transportation while middle vortex is opposite.The combination of shear convergence field and vapor transportation plays an important role in severe precipitation.The precipitation near cold vortex center is likely to occur in the north of baroclinic zone and left to where upper level jet exits,while rain in front or behind trough is located in the south of baroclinic zone and right to where upper level jet enters,and the secondary circulation resulting from upper level jet exists in precipitation area within baroclinic zone.The cyclonic circulation induced by high potential vorticity triggers ascending movement of rainfall near cold vortex center,combined with obvious activity of dry intrusion in the rainfall area behind trough.
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