重庆江北机场2025年4月两次春季雷暴对比分析

Comparison and Analysis of Two Spring Thunderstorm Processes in April 2025 at Chongqing Jiangbei Airport

摘要: 本文针对2025年4月3日和4月18日两次春季雷暴过程，从环流背景、探空资料及EC模式偏差三个维度开展分析。结果表明：环流形势是两次雷暴强度分化的关键，虽两者20时后均出现高空槽和中低层低值系统，但4月18日因高空槽更显著、中低层辐合切变线清晰且高低层系统协同，抬升条件远强于4月3日过程。探空数据亦显示其不稳定能量和垂直风切变更强，而湿度条件并非强度差异主因。两次春季雷暴都表现为湿度一般，传统对流有效位能(CAPE)、对流抑制能(CIN)等雷暴指标指示性较弱。EC模式预报表现呈明显分化，其对大尺度背景驱动的强对流预报效果较好，但对依赖中小尺度系统触发的强对流，其在动力与水汽要素协同模拟方面具有一定的局限性。

Abstract: This study analyzes two spring thunderstorm events on Apr 3 and 18, 2025, from three aspects: circulation background, sounding data, and ECMWF (EC) model biases. Results show the circulation pattern is key to the intensity difference between the two thunderstorms. Though both had upper-level troughs and low-level low systems after 20:00 (BT), the lifting conditions on Apr 18 were much stronger than those on Apr 3—due to a more prominent upper-level trough, clear convergence shear lines in the middle-low levels, and good coordination of upper-lower level systems. Sounding data also indicate stronger unstable energy and vertical wind shear on Apr 18, while humidity was not the main cause of the intensity difference. Both thunderstorms had moderate humidity, with weak indication from traditional indices like CAPE and CIN. The EC model’s forecasting performance varied significantly: it worked well for severe convection driven by large-scale backgrounds, but had limitations in simulating dynamic and water vapor element coordination for severe convection triggered by meso-small-scale systems.