气象Issue(1)：48-58,11.DOI:10.7519/j.issn.1000-0526.2014.01.006
2012年早春河南一次高架雷暴天气成因分析
Analysis on Weather Causes of an Elevated Thunderstorm in Henan in Early Spring 2012
摘要
Abstract
The conventional observation,new generation weather radar,lightning locating monitoring and NCEP 1°×1°analysis data are used to analyze the synoptic causes of the elevated thunderstorm in early spring of 2012 that was accompanied by a variety of weather phenomena and a flow configuration model of the elevated thunderstorm is established.The results showed that:(1 )the elevated thunderstorm occurs in the circulation situation of warm trough moving eastward and developing in middle latitudes.The near-neutral conditions instability stratification above the top of the boundary layer (biased in favor of weak conditional instability),which is in the forcing effect of positive vorticity advection in front of trough and warm and wet advection at low-levels,makes a larger range of strong upward motion above 700 hPa so that easterly winds in the rear of surface cold high has a role of cooling cushion on the production of the elevated convection.(2 )There is a strong inverse temperature layer in the lower atmosphere where elevated thun-derstorm exists.The warm and wet southwest low-level jet in front of temperature ridge at 700 hPa pro-vides ample moisture and energy for production of an elevated thunderstorm,causing weak conditions with unstable stratification and higher dew point above the top of low-level temperature inversion.The combi-nation of the two leads to the weak and most unstable convective available potential energy MUCAPE, whose value is between 10 and 50 J ·kg-1 .The elevated convection is caused by uplift of warm and wet block near and above the top of the inversion layer,corresponding to 1 .0-3 .0 m·s-1 maximum updrafts within thunderstorms.(3 )The elevated thunderstorm occurs in strong baroclinic environment,where there is a strong dynamic instability,in the lower level 0-6 km and 0-3 km vertical wind shear values are (3.0-3.7)×10-3 s-1 and (5.0-5.3)×10-3 s-1 respectiveny.(4)The -10℃ and -20℃ layers in this process are respectively in the height of 5 km and 6 .5 km,and the height of weak convective cloud top is more in the 6-8 km or above,exceeding the height of the freezing level and easily leading to the occurence of lightning.(5)From the flow configuration model,warm trough at high altitude,the strongly developed temperature ridge at middle and high layer,the warm and wet southwest low-level jet at 700 hPa and cold boundary center,cold temperature trough,surface cold high pressure etc.,make up a noteworthy affect-ing system.When these weather systems are favorable for configuration,the low-level temperature inver-sion,the establishment of weak condition unstable stratification at middle layer and the likelihood of ele-vated thunderstorms should be concerned.关键词
高架雷暴/强逆温层/弱条件不稳定/强垂直风切变/700 hPa暖湿急流/冷空气垫Key words
elevated thunderstorms/strong temperature inversion/weak condition unstable stratification/strong vertical wind shear/the warm and moisture jet at 700 hPa/cold air cushion分类
天文与地球科学引用本文复制引用
张一平,俞小鼎,孙景兰,梁俊平,吕林宜..2012年早春河南一次高架雷暴天气成因分析[J].气象,2014,(1):48-58,11.基金项目
中国气象局关键技术集成项目（CMAGJ2012M31）、河南省科技厅项目（112102310033）和河南省气象局项目（Z201201）共同资助 （）
