摘要
利用卫星云图、雷达、探空和地面自动气象站等气象资料,对2017年9月12日福建省西部的一场暴雨过程进行特征分析,探讨在副热带高压控制下出现较大范围暴雨过程的原因,结果表明:东亚大槽深入副热带高压北部,使得冷暖气流交汇于长江中下游以南地区,为处于副热带高压控制下的福建西部午后出现强降水创造有利环流条件;低层东北冷湿气流、中高层西南暖湿气流和地面冷锋是主要影响系统;副高控制下的福建西部白天升温明显,增强该地区上空的层结不稳定,沿海有云系增温不明显和台风"泰利"外围环流增强了闽浙沿海低层东北气流,两者共同作用增强地面冷锋强度和走向,有利于冷锋向西南移动,触发福建西部强对流的发展;从雷达回波特征看,该次过程既具有块状对流性强降水回波特征,又具有絮状稳定性降水回波特征,是锋面降水与局地热对流降水叠加结果。
With meteorological data from weather satellites,radars,sounding and surface automatic weather stations,the characteristics of a heavy rain weather on September 12,2017 were studied to analyze the causes for extensive heavy rain under the control of a subtropical high.The result is shown as follows.As a major trough in East Asia extended deep into the subtropical high,cold and warm air streams converged over the area south of the middle and lower reaches of the Yangtze River so that favorable circulation conditions became available for the post-midday severe rainfall in western Fujian.A low-level northeasterly cold and wet air flow,a mid-and high-level southwesterly warm and wet air flow and a cold surface front were the main governing systems.Under the control of the subtropical high,temperature rose significantly in the daytime in western Fujian to increase the stratiform instability over the area.Coastal temperature did not rise much due to the effect of clouds there and circulation at the periphery of Typhoon Talim enhanced a northeasterly flow over the coastal areas of Fujian and Zhejiang.Their combined action increased the intensity of the cold surface front and stabilized the moving direction to favor the cold front to move to the southwest and trigger convection to develop vigorously in western Fujian.It is seen from satellite imagery and radar echo that this weather process is characteristic of lump-shaped cloud cluster echoes of severe convective rainfall and cotton-shaped cloud cluster echoes of steady rainfall,resulting from the superimposition of frontal rainfall and local thermal convective rainfall.
作者
黄元森
高诗妍
林江
HUANG Yuan-sen;GAO Shi-yan;LIN Jiang(Meteorological Bureau of Nanping City,Nanping Fujian 353000;Meteorological Bureau of Ningde,Ningde Fujian 352100)
出处
《广东气象》
2019年第1期14-17,共4页
Guangdong Meteorology
基金
福建省基础性公益事业项目-<致灾暴雨监测和精细化预报服务>子项目
关键词
天气学
暴雨
夏季
副热带高压
冷锋
局地热对流
福建省
synoptics
heavy rain
summer
subtropical high
cold front
local thermal convection
Fujian province
