摘要
利用数值预报产品、常规观测资料、非常规观测资料(卫星云图、多普勒雷达、区域自动站等资料),采用天气学诊断方法,从大尺度环流背景、影响系统、物理量场等方面,对临汾市2013-05-22—23强对流天气过程进行诊断分析。结果表明,500 hpa西风槽东移带来的冷空气与低层暖湿气流共同作用是形成区域性暴雨的主要原因。700 hPa低涡横切变线是暴雨的主要影响系统;低层辐合、高层辐散,且抽吸作用明显;上干下湿的不稳定层结有利于对流的产生和发展;我市处在K指数≥35,CAPE 600-700区,其潜在不稳定能量较大,可能产生的垂直速度也较大;云图上β中尺度特征明显,对流云团首先在低涡切变线西侧形成,随着低涡切变线东北移,对流云团迅速发展东移,这些都是暴雨形成的直接影响系统。雷达强度回波上表现为块状回波,>45 dbz的雷达回波与暴雨落区对应较好;EC细网格、T639高分辨率预报产品对对流性天气特征物理量(K指数、CAPE、T-Td)指导意义明显,可将其作为对流性天气短期预报关注的重点。
The use of numerical forecast products, conventional observation data and unconventional observation data,（ satellite cloud picture, doppler radar, regional automatic station data ） , the diagnosis methods of weather from the large scale circulation background, influence system, the physical quantity field, etc., of Linfen city in the 2013-05-22-23 strong convective weather process for diagnosis analysis. The results showed that 500 hpa west wind trough eastward warm moist air flows caused by cold air and lower work together is the main reason for the formation of regional heavy rain. 700 hPa low vortex transverse direction of heavy rain is the main influencing system; Low-level convergence and high-level divergence, and suction effect is obvious; Dry the wet on unstable stratification is conducive to the emergence and development of convection; Zhuhai in K exponential 35, or CAPE area 600-700, the potential instability energy is larger, can produce vertical velocity is large; Cloud on beta obvious mesoscale features, convective cloud formed in the first place in the west side of the low vortex shear line, move as northeast vortex shear line, rapid development of convective cloud cluster eastward, these are the direct influence rainstorm system. Characterized by massive echo radar echo intensity, 〉 45 DBZ radar echo with heavy rain fall area corresponding to the better; EC fine grid and T639 high-resolution forecast products of convection weather characteristic quantities （ K index, CAPE, T - Td ） guiding significance, it can be as the convectional weather concerns of the short-term forecast.
出处
《科技与创新》
2014年第10期136-138,共3页
Science and Technology & Innovation
关键词
强对流天气
诊断
云图
雷达回波特征
strong convective weather
diagnosis
cloud
radar echo characteristics
