气象2026，Vol.52Issue(6)：686-701,16.DOI:10.7519/j.issn.1000-0526.2026.042701
2025年北京超长极端暴雨的精细化特征与成因分析
Refined Characteristics and Causes of the Ultra-Long-Duration Extreme Torrential Rain in Beijing in 2025
摘要
Abstract
Using refined hourly meteorological observations,radar data,and other multi-source observation data,along with ERA5 reanalysis data,this paper analyzes the characteristics and causes of the ultra-long-duration regional extreme torrential rain event that occurred in Beijing from 23 to 29 July 2025.The results indicate that this event was the longest-lasting heavy precipitation event in the past decade,and the number of stations with daily precipitation ≥50 mm and the daily maximum precipitation during the event ranked the second after the extreme torrential rain event on 30 July 2023.This event also exhibited signifi-cant nocturnal rainfall characteristics,with the maximum hourly rainfall intensity concentrated in the period from midnight to early morning hours.The areas of heavy precipitation were primarily distributed over the plains in front of the Yanshan Mountains and on the windward slopes.This torrential rain event was main-ly influenced by the subtropical high system,low-latitude tropical weather systems,and mid-to-high-lati-tude westerly troughs.The analysis of the geopotential height anomaly field from July 23 to 28 reveals that the subtropical high was positioned more northward than usual.The tropical low-pressure system over-lapped with the abnormally northward-shifted peripheral airflow of the subtropical high,forming a sus-tained southerly airflow that was transported northward to the Beijing Region,which provided abundant moisture for the extreme precipitation.The moisture content was significantly higher than the climatologi-cal average,with areas of high specific humidity overlapping with southerly wind anomalies.Coupled with the orographic uplift effect of the Yanshan Mountains,these factors significantly enhanced precipitation in-tensity.A prolonged high-humidity environment was maintained below 500 hPa throughout this event,with the average specific humidity at 925 hPa(14.3 g·kg-1),850 hPa(12.2 g·kg-1),and 700 hPa(7.4 g·kg-1)exceeding the average values recorded in torrential rain events over the past decade(based on statistics from the Beijing Sounding Station).Under the daytime conditions of high temperature and hu-midity,unstable energy was accumulated.At night,the enhanced low-level jet,combined with terrain lift-ing,contributed to the pronounced nocturnal rainfall characteristics of this torrential rain event.The major impact systems of the extreme torrential rain over the night of 26 July could not be identified with the con-ventional data including ERA5 reanalysis data,but the radar imagery clearly reveals that the main impact systems of the extreme torrential rain were the low-level convergence line and the small-scale low-level jet.关键词
超长极端暴雨/精细化特征/成因Key words
ultra-long-duration extreme torrential rain/refined characteristic/cause分类
天文与地球科学引用本文复制引用
吴珍珍,林浩,薛峰,向钢,黄小玉,毛紫怡,欧小锋,闫如柳..2025年北京超长极端暴雨的精细化特征与成因分析[J].气象,2026,52(6):686-701,16.基金项目
中国气象局高影响天气(专项)重点开放实验室项目(2024-G-10)、2024年湖南省重大研发专项(2024AQ2016)和中国气象局创新发展专项(CXFZ2025J136)共同资助 （专项）
