一次台风引发的远距离暴雨诊断分析  

Analysis of Effect of Typhoon Circulation on a Remote Rainstorm

作　　者：张雪慧[1] 田德宝[1] 曾令建 张珊珊 陆琛莉[1] 谢帅 ZHANG Xuehui;TIAN Debao;ZENG Lingjian;ZHANG Shanshan;LU Chenli;XIE Shuai(Jiaxing Meteorological Service,Zhejiang,Jiaxing 314050)

机构地区：[1]浙江省嘉兴市气象局,嘉兴314050

出　　处：《气象科技》2021年第5期777-784,共8页Meteorological Science and Technology

基　　金：浙江省自然科学基金项目(LY19D050001);嘉兴市民生科技创新项目(2021AD30017)共同资助。

摘　　要：台风对远距离暴雨的作用形式复杂,容易出现极端降水,量级和落区的预报难度大。2014年8月8日江苏东部到浙江北部出现暴雨,通过研究数值预报形势场、再分析场和各类实况资料,发现暴雨的产生与远在1300km外的西太平洋上的台风"夏浪"有关。江苏东部暴雨主要由中尺度涡旋造成,台风通过北侧偏东气流向暴雨区输送暖湿空气,有利于暴雨的形成与维持;浙江北部暴雨是中尺度涡旋与台风环流结合的产物,台风北上过程中,中心与中尺度涡旋逐渐靠近,台风外围环流对涡旋产生牵引,流场形势发生改变,引导弱冷空气在浙北近海附近与暖空气交汇辐合抬升引发暴雨,不稳定能量剧烈释放产生的中γ尺度气旋造成了极端强降水。The effect of typhoon circulation on remote rainstorms is complicated,and extreme precipitation is easy to occur,so it is difficult to forecast accurately the level and falling area.On August 8 th,2014,there were heavy rains from the east of Jiangsu to the north of Zhejiang.Using the numerical forecast situation,the NCEP final operational Global Data and actual observation data,we found collections between the heavy rains and the typhoon"XiaoLong",1300 km away on the western Pacific Ocean.The mesoscale vortex mainly caused the rainstorm in the eastern part of Jiangsu Province.The warm and moist air was transmitted to the rainstorm area by the easterly flow of typhoon north side,which was conducive to the formation and maintenance of the rainstorm.Then the rainstorm in the northern part of Zhejiang was caused by the combined effect of the mesoscale vortex and the typhoon circulation.In the process of typhoon moving northward,the distance between the typhoon centre and the vortex shortened,and then the typhoon circulation produced traction on the vortex,which changed the flow field situation.The northwest airflow brought weak cold air to the northern part of Zhejiang and met the warm air in low-level in the inshore region,causing convergence uplift and the rainstorm.Then,the convective instability energy broke out,resulting in the mesoscale-γcyclone,which caused the extreme heavy precipitation.

关 键 词：远距离暴雨 台风环流 中尺度涡旋 

分 类 号：P458[天文地球—大气科学及气象学]