Journal of Arid Meteorology

Previous Articles     Next Articles

Cases Study of First Heavy Rainfall in the Pre-rainy Season in South China

CHEN Shenpeng1, SUN Guowu2   

  1. (1. Shenzhen National Climate Observatory/Climate Center, Shenzhen 518040, China;
    2. Lanzhou Institute of Arid Meteorology, CMA, Lanzhou 730020, China)
  • Online:2018-03-05 Published:2018-03-05



  1. (1.深圳市国家气候观象台,广东深圳518040;2.中国气象局兰州干旱气象研究所,甘肃兰州730020)
  • 作者简介:陈申鹏(1984— ),男,云南宣威人,工程师,主要从事天气预报和气候预测相关工作.
  • 基金资助:



Abstract:Based on the grid data of NCEP/NCAR and precipitation data of 97 stations in South China, the precipitation characteristics, circulation situation and dynamic factors of the first heavy rainfall in the pre-rainy season in South China in 2014 and 2015 were analyzed. The results show that the two precipitation processes were both connected with the low trough on the east side of the Qinghai Tibet Plateau moving eastward and deepening over South China. The vorticity equation diagnosis showed that increase of cyclonic vorticity at low-level and anticyclone vorticity at high-level, were mainly connected with the horizontal divergence term (C), while vertical motion within the precipitation system, was mainly connected with the increase of the horizontal advection term (A) with height. The precipitation system tended to move towards areas where the horizontal divergence term C was negative at higher level and positive at lower level or where the horizontal advection term A was positive at higher level and negative at lower level. Difference in layer thickness and intensity of vapor convergence led to difference in rainfall intensity of the two precipitation processes. Finally, for the two strong precipitation processes, moving eastward and deepening of low trough on the east side of the Qinghai Tibet Plateau caused by power factor were the common feature, which could be used as reference in weather-forecasting practice.

Key words: the pre-rainy season, the first heavy rainfall, vorticity equation, low trough, horizontal divergence term, horizontal advection term



关键词: 前汛期, 首场强降水, 涡度方程, 低槽, 水平辐散项, 水平平流项

CLC Number: