高空槽背景下北京首都及大兴国际机场春季初雷过程诊断分析

Diagnostic Analysis of the First Lightning Process in Spring in Beijing Capital and Daxing International Airport under the Background of High-Altitude Trough

摘要: 2023年4月28日北京首都及大兴国际机场出现了2023年的首场雷暴天气，对航空运输的安全性影响较大。文章对此次初雷过程的天气学成因进行了诊断分析。结果表明：出现在中高层的槽线以及地面的锋面系统，是此次初雷发生的主要影响天气系统；在此次初雷天气过程中，首都及大兴国际机场地区上空相对湿度较大，为对流性降水的发生发展提供了有利的水汽条件；在低涡中心不断发展时，伴随高空气流向南输送，斜压能量在中层大气中得到大量积累，为此次强对流天气过程的发展提供了有利的动力条件；同时层结曲线落后于状态曲线，表明在北京地区上空积累了大量不稳定能量，有利于强对流天气的发展。

Abstract: On April 28, 2023, the first thunderstorm weather in 2023 occurred in Beijing Capital and Daxing International Airport, which had a great impact on the safety of air transportation. In this paper, the synoptic causes of the first lightning process are diagnosed and analyzed. The results show that the trough line in the middle and upper levels and the frontal system on the ground are the main weather systems affecting the occurrence of the first lightning. During the first lightning process, the relative humidity over the capital and Daxing International Airport was relatively high, which provided favorable water vapor conditions for the occurrence and development of convective precipitation. With the continuous development of the low vortex center, the baroclinic energy accumulated in the middle atmosphere with the southward transport of high air, which provided favorable dynamic conditions for the development of the severe convective weather process. At the same time, the stratification curve lags behind the state curve, indicating that a large amount of unstable energy is accumulated over the Beijing area, which is conducive to the development of strong convective weather.