Mechanisms of an Elevated Thunderstorm Process over Southern China in the Early Spring of 2009

  • BAO Yuanyuan ,
  • KANG Zhiming ,
  • LI Lun ,
  • HUANG Xiaoyu
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  • National Meteorological Center, Beijing 100081, China;2. Hunan Province Weather Forecast Office, Changsha 410007, China

Received date: 2013-03-07

  Online published: 2015-04-28

Abstract

An elevated thunderstorm process in southern China on 3 March 2009 is analyzed by using conventional observation, 6.7 μm satellite vapor images and TBB, lighting location and NCEP/NCAR reanalysis. The main synoptic systems include trough at middle-low levels, vortex and shear line, low-level jet, upper-level southern and northern western jet. The storm is triggered by low-level jet warm water vapor transportation and invading of high-level cold air. The boundary is dynamically stable for the existence of a thick cold pad. Convection instability appears between low-level warm and humid southwest jet and the cold and dry air at middle and high levels, and strengthened by the descending motion of the upper jet. A strong baro-clinic frontal zone is formed by the meeting of southwest jet and the cold and dry air northward at low-middle levels. The confluence of the southwest air descending branch and the cold and dry air from northern area causes northeast backflow which couples with the southwest winds above the boundary and forms a secondary front circulation, the ascending air at middle-upper levels couples with descending air of northern westerly jet causes another secondary positive circulation, the two northward titling secondary circulations are very favorable for tilting ascending movement. The warm advection and water vapor flux convergence of low-level jet, the strong divergence at the right entrance of upper-level western jet and the convergence along the southern upper-level jet are also contributable for meso-scale ascending movement. Thunders and hails appear usually at the dense band of θse, low-level jet speeds, water vapor flux and 300 hPa divergence. In addition, the environmental conditions as the thin humid layer, strong wind shear, low-level temperature inversion, ascending motion at -20~0℃ super cooled water layer are very advantageous to thunderstorms.

Cite this article

BAO Yuanyuan , KANG Zhiming , LI Lun , HUANG Xiaoyu . Mechanisms of an Elevated Thunderstorm Process over Southern China in the Early Spring of 2009[J]. Plateau Meteorology, 2015 , 34(2) : 515 -525 . DOI: 10.7522/j.issn.1000-0534.2013.00187

References

[1]Wilson J W, Brante F G, Andrew C N, et al. The role of boundary layer convergence zones and horizontal rolls in the initiation of thunderstorms: A case study[J]. Mon Wea Rev, 1992, 20(1): 785-815.
[2]王秀明, 俞小鼎, 周小刚, 等. '6·3’区域致灾雷暴大风形成及维持原因分析[J]. 高原气象, 2012, 31(2): 504-514.
[3]王彦, 于莉莉, 朱男男, 等. 渤海湾海风锋与雷暴天气[J]. 高原气象, 2011, 30(1): 245-251.
[4]樊李苗, 俞小鼎. 中国短时强对流天气的若干环境参数特征分析[J]. 高原气象, 2013, 32(1): 156-165, doi: 10.7522/j.issn.1000-0534.2013.00016.
[5]李江波, 王宗敏, 王福侠, 等. 华北冷涡连续降雹的特征与预报[J]. 高原气象, 2011, 30(4): 1119-1131.
[6]陈英英, 唐仁茂, 李德俊, 等. 利用雷达和卫星资料对一次强对流天气过程的云结构特征分析[J]. 高原气象, 2013, 32(4): 1148-1156, doi: 10.7522/j.issn.1000-0534.2012.00108.
[7]井喜, 李社宏, 屠妮妮, 等. 黄河中下游一次MCC和中-β尺度强对流云团相互作用暴雨过程综合分析[J]. 高原气象, 2011, 30(4): 913-928.
[8]潘留杰, 张红芳, 王楠, 等. 陕西一次强对流天气过程的中尺度及雷达观测分析[J]. 高原气象, 2013, 32(1): 278-289, doi: 10.7522/j.issn.1000-0534.2013.00027.
[9]Colman B R. Thunderstorms above frontal surfaces in environments without positive CAPE. Part I: A climatology[J]. Mon Wea Rev, 1990, 118: 1103-1121.
[10]Colman B R. Thunderstorms above frontal surfaces in environments without positive CAPE. Part II: Organization and instability mechanisms[J]. Mon Wea Rev, 1990, 118: 1123-1144.
[11]Grant B N. Elevated cold-sector severe thunderstorms: A preliminary study[J]. Natl Wea Dig, 1995, 19(4): 25-31.
[12]Junker N W, Schneider R S, Scofield R A. The meteorological conditions associated with the great Midwest flood of 1993[C]. Preprints, 14<sup>th</sup> Conf. on Weather Analysis and Forecasting, Dallas, TX, Amer Meteor Soc, 1995, 4: 13-17.
[13]Moore J T, Glass F H, Graves C E, et al. The environment of warm-season elevated thunderstorms associated with heavy rainfall over the central United States[J]. Wea Forecasting, 2003, 18: 861-878.
[14]Dosswell Ⅲ C A. Severe convective storms[J].Meteor Monogr, 2001, 69: 1-26.
[15]冯晋勤, 俞小鼎, 傅伟辉, 等. 2010年福建一次早春强降雹超级单体风暴对比分析[J]. 高原气象, 2012, 31(1): 239-250.
[16]Johns R H, Doswell Ⅲ C A. Severe local storms forecasting[J]. Wea Forecasting, 1992, 7: 588-612.
[17]朱乾根, 瑞林锦瑞, 寿绍文, 等. 天气学原理[M]. 北京: 气象出版社, 2000: 408.
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