Cause Analysis of a Double-cyclone Type of Rainstorm Process with Easterly Wave

• 作者: Chen Qing Jin Xuanxi Lv Weiwei Lv Xiaohua Tang Zuoyang
• 来源期刊: 气象与环境研究:英文版
• 学科: 地球科学
• 关键词: RAINSTORM DIAGNOSTIC analysis SUBTROPICAL high pressure Easterly WAVE Water vapor source
• 年，卷（期）: 2019,（2）
• 页码范围: 15-19
• 页数: 5页
• 分类号: P458.121.1

摘要

On the basis of comprehensive analysis on weather background and main influencing system of rainstorm formation,using NCEP reanalysis data,rainfall data of Shaoyang ground regional automatic station,a new generation of Doppler weather radar product information,etc.,high-altitude weather situation and physical formation mechanism of local double-cyclone type of rainstorm process with easterly wave in Shaoyang area on August 14,2016 were analyzed in detail,to find out prophase signal features which had indicating significance for rainstorm forecast. The results showed that:(1) the position of zonal subtropical high pressure in east-west direction was the necessary condition for the formation of easterly wave.(2) The rainstorm formation was closely related to double tropical depressions acting in the south of subtropical high pressure,and westward movement of easterly wave over 500 hPa and low-pressure inverted trough at low layer were main impact systems of the rainstorm.(3) Continuous flow of water vapor from the South China Sea to northwest was the source of water vapor required by this rainstorm.(4) Numerical prediction model products had certain guiding significance for forecasting the heavy precipitation,with important reference value.(5) Doppler radar products had strong forecasting ability in the nowcasting of rainstorm falling zone,which was an important measure of correcting forecast errors.