Analysis of the characteristics of thunderstorm echo group under the control of a subtropical high
In order to better understand the characteristics of thunderstorm echo groups generated by afternoon heat convection under the subtropical high situation in Jiangxi Province,this article analyzes the characteristics of thunderstorm echo groups generated by afternoon heat convection under the subtropical high situation from August 19,2023 in Jiangxi Province by using conventional weather data,data of ground automatic meteorological station,radar data,and lightning data in Jiangxi Province.The results show that the rainstorm is mainly formed by 3 h short-term heavy rainfall,accompanied by thunderstorms and gales.The negative flash frequency is close to the total flash frequency,while the positive flash frequency is relatively less.The lightning data line with 200 occurrences in 10 minutes is the threshold line for judging heavy rainfall.Jiangxi is under the control of subtropical high pressure,there is an obvious outflow area at 200 hPa,low-pressure circulation is in the lower layers,humidity is high,and there is an obvious dry tongue at 500 hPa.There is a surface convergence line in the northeast of Jiangxi.Under the subtropical high situation,small-scale local geothermal thunderstorms generated by surface heating in the afternoon vigorously develop into mesoscale thunderstorm echo groups under appropriate vertical velocity environments.The convective cell echoes in the thunderstorm echo group develop vigorously,with multiple cells developing into super cells,with a central intensity of up to 70 dBZ and a strong echo area from 13 km2 to 178 km2.It is hoped that this study results can provide an analytical basis for the early warning and prediction of catastrophic weather caused by thunderstorm echo groups under the control of the Jiangxi subtropical high.
subtropical highafternoon heat convectionthunderstorm echo group
万方数据
维普
