Chen Xunlai, Xu Ting, Wang Rui, et al. Fine observation characteristics and causes of "9·7" extreme heavy rainstorm over Pearl River Delta, China. J Appl Meteor Sci, 2024, 35(1): 1-16. DOI: 10.11898/1001-7313.20240101.
Citation: Chen Xunlai, Xu Ting, Wang Rui, et al. Fine observation characteristics and causes of "9·7" extreme heavy rainstorm over Pearl River Delta, China. J Appl Meteor Sci, 2024, 35(1): 1-16. DOI: 10.11898/1001-7313.20240101.

Fine Observation Characteristics and Causes of "9·7" Extreme Heavy Rainstorm over Pearl River Delta, China

More Information
  • On 7-8 September 2023, the Pearl River Delta experiences an extremely heavy rainstorm, known as "9·7" extreme rainstorm. Multi-source data are comprehensively utilized, including high-density automatic weather station data, sounding data, wind profiler data, Doppler radar data, high-resolution measurements from FY-4B satellite, and the fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis (ERA5), to analyze the fine precipitation characteristics and causes of this case. Results indicate that the extremely heavy rainstorm is characterized by area of coverage, wide coverage area, long duration, and substantial rainfall. The extremely heavy rainstorm is caused by the combined interaction of 200 hPa upper-level divergence, the middle-level weak guiding flow, the lower-level southwest monsoon, and the residual vortex of Typhoon Haikui (2311). It is generated by the long-term horizontal scale of about 100 km banded mesoscale convective complex, with significant train effect and warm cloud precipitation characteristics. The centroid of intense echoes with an intensity greater than 45 dBZ is located below 4 km during the most intense precipitation stage, while intense echoes with an intensity greater than 30 dBZ can last for up to 21 hours in Shenzhen. In terms of raindrop distribution characteristics extreme rainfall is mainly caused by a high density of small and medium-sized raindrops. When the rainfall intensity exceeds 20 mm·h-1, the size of raindrop particles increases, but the numerical concentration significantly decreases. Results in an increase in raindrop size but a decrease in the number of concentrations. The duration, intensity, and area of extreme rainstorms have a strong correlation with the fluctuation of the low-level jet in the boundary layer and the location of the core area of the jet. Heavy rainfall occurs within 1-2 hours after a rapid strengthening of the low-level jet index. After the low-level jet index decreases, the intensity of heavy precipitation diminishes. Variations in the low-level jet and low-level jet index have significant implications for heavy rainfall. The prolonged presence of Typhoon Haikui residual vortex in the Pearl River Delta is the synoptic-scale cause of this extremely heavy rainstorm. The residence time of the lingering vortex exceeds 16 hours. During that time, the deep boundary layer low-level jet continuously transfers warm water vapor to the lingering vortex. Simultaneously, the water vapor from the western Pacific, carried by the northeast airflow of Typhoon Yunyeung, and the southwest monsoon water vapor transfers through the Bay of Bengal, Indochina Peninsula, and the South China Sea, ultimately results in the formation of a stable mesoscale convergence line near the Pearl River Delta, causing an extremely heavy rainstorm.
  • Fig  1.   Rainfall(unit:mm)(a) and maximum rainfall intensity(unit:mm·h-1)(b) from 1600 BT 7 Sep to 1600 BT 8 Sep in 2023

    Fig  2.   Hourly rainfall of typical stations from 1700 BT 7 Sep to 1600 BT 8 Sep in 2023

    Fig  3.   Wind(the barb), wind speed(the shaded) and geopotential height(the red contour, unit:dagpm)from 5 Sep to 8 Sep in 2023

    Fig  4.   FY-4B TBB from 7 Sep to 8 Sep in 2023

    Fig  5.   Radar combination reflectivity of Guangdong from 7 Sep to 8 Sep in 2023

    Fig  6.   Time-height section of radar combination reflectivity(the shaded) and rainfall intensity(the black solid line)at Xiaowutong Station of Shenzhen from 1800 BT 7 Sep to 2000 BT 8 Sep in 2023

    Fig  7.   Raindrop number concentration(the shaded), raindrop diameter(height of the shaded)and rainfall intensity(the black solid line) at Shiyan Station of Shenzhen from 1600 BT 7 Sep to 1600 BT 8 Sep in 2023

    Fig  8.   Scatter plots of rainfall intensity with raindrop mass-weighted average diameter(a)and standardized number concentration(b) at Shiyan Station of Shenzhen from 1600 BT 7 Sep to 1600 BT 8 Sep in 2023

    Fig  9.   Wind at 850 hPa(the red solid line denotes converging line) from 7 Sep to 8 Sep in 2023

    Fig  10.   Wind profile of radar(the shaded denotes wind speed no less than 12 m·s-1) at Longgang Station of Shengzhen(a) and low jet index and hourly rainfall(b) from 7 Sep to 8 Sep in 2023

    Fig  11.   Wind(the vector) and divergence(the shaded denotes less than -2×10-5 s-1)at 975 hPa from 7 Sep to 8 Sep in 2023

    Fig  12.   Water vapor transport at 925 hPa(the vector, unit:g·cm-1·hPa·s-1)from 7 Sep to 8 Sep in 2023(the shaded denotes water vapor flux)

  • [1]
    何立富, 陈涛, 孔期. 华南暖区暴市研究进展. 应用气象学报, 2016, 27(5):559-569. DOI: 10.11898/1001-7313.20160505

    He L F, Chen T, Kong Q. A review of studies on prefrontal torrential rain in South China. J Appl Meteor Sci, 2016, 27(5): 559-569. DOI: 10.11898/1001-7313.20160505
    [2]
    翟盘茂, 李蕾, 周佰铨, 等. 江淮流域持续性极端降水及预报方法研究进展. 应用气象学报, 2016, 27(5): 631-640. DOI: 10.11898/1001-7313.20160511

    Zhai P M, Li L, Zhou B Q, et al. Progress on mechanism and prediction methods for persistent extreme precipitation in the Yangtze-Huai River Valley. J Appl Meteor Sci, 2016, 27(5): 631-640. DOI: 10.11898/1001-7313.20160511
    [3]
    伍红雨, 邹燕, 刘尉. 广东区域性暴雨过程的定量化评估及气候特征. 应用气象学报, 2019, 30(2): 233-244. DOI: 10.11898/1001-7313.20190210

    Wu H Y, Zou Y, Liu W. Quantitative assessment of regional heavy rainfall process in Guangdong and its climatological characteristics. J Appl Meteor Sci, 2019, 30(2): 233-244. DOI: 10.11898/1001-7313.20190210
    [4]
    Wang Y J, Zhou B T, Qin D H, et al. Changes in mean and extreme temperature and precipitation over the arid region of northwestern China: Observation and projection. Adv Atmos Sci, 2017, 34(3): 289-305. DOI: 10.1007/s00376-016-6160-5
    [5]
    刘菲凡, 郑永光, 罗琪, 等. 京津冀及周边一般性降水与短时强降水特征对比. 应用气象学报, 2023, 34(5): 619-629. DOI: 10.11898/1001-7313.20230510

    Liu F F, Zheng Y G, Luo Q, et al. Comparison of characteristics of light precipitation and short-time heavy precipitation over Beijing, Tianjin, Hebei and neighbouring areas. J Appl Meteor Sci, 2023, 34(5): 619-629. DOI: 10.11898/1001-7313.20230510
    [6]
    谌芸, 孙军, 徐珺, 等. 北京721特大暴雨极端性分析及思考(一)观测分析及思考. 气象, 2012, 38(10): 1255-1266.

    Chen Y, Sun J, Xu J, et al. Analysis and thinking on the extremes of the 21 July 2012 torrential rain in Beijing part Ⅰ: Observation and thinking. Meteor Mon, 2012, 38(10): 1255-1266.
    [7]
    宝兴华, 夏茹娣, 罗亚丽, 等. "21·7"河南特大暴雨气象和水文雨量观测对比. 应用气象学报, 2022, 33(6): 668-681. DOI: 10.11898/1001-7313.20220603

    Bao X H, Xia R D, Luo Y L, et al. Comparative analysis on meteorological and hydrological rain gauge observations of the extreme heavy rainfall event in Henan Province during July 2021. J Appl Meteor Sci, 2022, 33(6): 668-681. DOI: 10.11898/1001-7313.20220603
    [8]
    田付友, 郑永光, 张小玲, 等. 2017年5月7日广州极端强降水对流系统结构、触发和维持机制. 气象, 2018, 44(4): 469-484.

    Tian F Y, Zheng Y G, Zhang X L, et al. Structure, triggering and maintenance mechanism of convective systems during the Guangzhou extreme rainfall on 7 May 2017. Meteor Mon, 2018, 44(4): 469-484.
    [9]
    齐道日娜, 何立富, 王秀明, 等. "7·20"河南极端暴雨精细观测及热动力成因. 应用气象学报, 2022, 33(1): 1-15. DOI: 10.11898/1001-7313.20220101

    Chyi D, He L F, Wang X M, et al. Fine observation characteristics and thermodynamic mechanisms of extreme heavy rainfall in Henan on 20 July 2021. J Appl Meteor Sci, 2022, 33(1): 1-15. DOI: 10.11898/1001-7313.20220101
    [10]
    段汀, 陈权亮, 廖雨静. "21. 7"郑州极端暴雨的形成过程及致灾机理分析. 气象科学, 2022, 42(2): 152-161.

    Duan T, Chen Q L, Liao Y J. Analysis of "21. 7" extreme rainstorm formation process and disaster mechanism in Zhengzhou. J Meteor Sci, 2022, 42(2): 152-161.
    [11]
    鲍名. 近50年我国持续性暴雨的统计分析及其大尺度环流背景. 大气科学, 2007, 31(5): 779-792.

    Bao M. The statistical analysis of the persistent heavy rain in the last 50 years over China and their backgrounds on the large scale circulation. Chinese J Atmos Sci, 2007, 31(5): 779-792.
    [12]
    孙婧超, 管兆勇, 李明刚, 等. 华南地区7-10月两类区域性极端降水事件特征及环流异常对比. 气象学报, 2019, 77(1): 43-57.

    Sun J C, Guan Z Y, Li M G, et al. Anomalous circulation patterns in association with two types of regional daily precipitation extremes over South China from July to October. Acta Meteor Sinica, 2019, 77(1): 43-57.
    [13]
    符娇兰, 马学款, 陈涛, 等. "16·7"华北极端强降水特征及天气学成因分析. 气象, 2017, 43(5): 528-539.

    Fu J L, Ma X K, Chen T, et al. Characteristics and synoptic mechanism of the July 2016 extreme precipitation event in North China. Meteor Mon, 2017, 43(5): 528-539.
    [14]
    方翀, 毛冬艳, 张小雯, 等. 2012年7月21日北京地区特大暴雨中尺度对流条件和特征初步分析. 气象, 2012, 38(10): 1278-1287.

    Fang C, Mao D Y, Zhang X W, et al. Analysis on the mesoscale convective conditions and characteristics of an extreme torrential rain in Beijing on 21 July 2012. Meteor Mon, 2012, 38(10): 1278-1287.
    [15]
    杨舒楠, 路屹雄, 张芳华, 等. 热带风暴艾云尼持续性强降水成因分析. 气象, 2021, 47(1): 106-116.

    Yang S N, Lu Y X, Zhang F H, et al. Analysis on causes of persistent heavy rainfall brought by tropical storm Ewiniar. Meteor Mon, 2021, 47(1): 106-116.
    [16]
    林良勋, 梁巧倩, 黄忠. 华南近海急剧加强热带气旋及其环流综合分析. 气象, 2006, 32(2): 14-18.

    Lin L X, Liang Q Q, Huang Z. Analysis of circulation pattern of rapidly intensified offshore tropical cyclones of South China. Meteor Mon, 2006, 32(2): 14-18.
    [17]
    陈联寿, 丁一汇. 西太平洋台风概论. 北京: 科学出版社, 1979.

    Chen L S, Ding Y H. Introduction to Typhoons in the Western Pacific. Beijing: Science Press, 1979.
    [18]
    林文, 林长城, 李白良, 等. 登陆台风麦德姆不同部位降水强度及谱特征. 应用气象学报, 2016, 27(2): 239-248. DOI: 10.11898/1001-7313.20160212

    Lin W, Lin C C, Li B L, et al. Rainfall intensity and raindrop spectrum for different parts in landing Typhoon Matmo. J Appl Meteor Sci, 2016, 27(2): 239-248. DOI: 10.11898/1001-7313.20160212
    [19]
    黄燕燕, 蒙伟光, 冯业荣, 等. 华南登陆台风降水不对称性及持续性问题. 气象, 2023, 49(4): 385-399.

    Huang Y Y, Meng W G, Feng Y R, et al. Problems in asymmetry and sustainability of landfalling typhoon precipitation over South China. Meteor Mon, 2023, 49(4): 385-399.
    [20]
    毛志远, 付丹红, 黄彦彬, 等. 台风贝碧嘉(1816)外围云系结构与降水特征. 应用气象学报, 2022, 33(5): 604-616. DOI: 10.11898/1001-7313.20220508

    Mao Z Y, Fu D H, Huang Y B, et al. Peripheral cloud system structure and precipitation characteristics of Typhoon Bebinca(1816). J Appl Meteor Sci, 2022, 33(5): 604-616. DOI: 10.11898/1001-7313.20220508
    [21]
    颜玲, 周玉淑, 王咏青. 相似路径台风Soudelor(1513)与Matmo(1410)登陆前后的降水分布特征及成因的对比分析. 大气科学, 2019, 43(2): 297-310.

    Yan L, Zhou Y S, Wang Y Q. Analysis on different characteristics and causes of precipitation distribution during the landing of Typhoon "Soudelor"(1513) and Typhoon "Matmo" (1410) with similar tracks. Chinese J Atmos Sci, 2019, 43(2): 297-310.
    [22]
    卢珊, 王黎娟, 管兆勇, 等. 低纬季风涌影响登陆台风"榴莲"(0103)和"碧利斯"(0604)暴雨增幅的比较. 大气科学学报, 2012, 35(2): 175-185.

    Lu S, Wang L J, Guan Z Y, et al. Comparison of impacts of low-latitude monsoon surge on the enhanced rainstorm from landing typhoons Durian and Bilis. Trans Atmos Sci, 2012, 35(2): 175-185.
    [23]
    何立富, 陈双, 郭云谦. 台风利奇马(1909)极端强降雨观测特征及成因. 应用气象学报, 2020, 31(5): 513-526. DOI: 10.11898/1001-7313.20200501

    He L F, Chen S, Guo Y Q. Observation characteristics and synoptic mechanisms of Typhoon Lekima extreme rainfall in 2019. J Appl Meteor Sci, 2020, 31(5): 513-526. DOI: 10.11898/1001-7313.20200501
    [24]
    覃皓, 郑凤琴, 伍丽泉. 台风威马逊(1409)强度与降水变化的相互作用. 应用气象学报, 2022, 33(4): 477-488. DOI: 10.11898/1001-7313.20220408

    Qin H, Zheng F Q, Wu L Q. The interaction between intensity and rainfall of Typhoon Rammasun(1409). J Appl Meteor Sci, 2022, 33(4): 477-488. DOI: 10.11898/1001-7313.20220408
    [25]
    叶成志, 李昀英. 热带气旋"碧利斯"与南海季风相互作用的强水汽特征数值研究. 气象学报, 2011, 69(3): 496-507.

    Ye C Z, Li Y Y. A numerical study of the characteristics of strong moisture transport as a result of the interaction of tropical storm Bilis with the South China Sea monsoon. Acta Meteor Sinica, 2011, 69(3): 496-507.
    [26]
    程正泉, 林良勋, 杨国杰, 等. 超强台风威马逊快速增强及大尺度环流特征. 应用气象学报, 2017, 28(3): 318-326. DOI: 10.11898/1001-7313.20170306

    Cheng Z Q, Lin L X, Yang G J, et al. Rapid intensification and associated large-scale circulation of super Typhoon Rammasun in 2014. J Appl Meteor Sci, 2017, 28(3): 318-326. DOI: 10.11898/1001-7313.20170306
    [27]
    刘淑媛, 郑永光, 陶祖钰. 利用风廓线雷达资料分析低空急流的脉动与暴雨关系. 热带气象学报, 2003, 19(3): 285-290.

    Liu S Y, Zheng Y G, Tao Z Y. The analysis of the relationship between pulse of LLJ and heavy rain using wind profiler data. J Trop Meteor, 2003, 19(3): 285-290.
    [28]
    McAnelly R L, Cotton W R. Meso-β-scale characteristics of an episode of meso-α-scale convective complexes. Mon Wea Rev, 1986, 114(9): 1740-1770. DOI: 10.1175/1520-0493(1986)114<1740:MSCOAE>2.0.CO;2
    [29]
    Doswell C A III, Brooks H E, Maddox R A. Flash flood forecasting: An ingredients-based methodology. Wea Forecasting, 1996, 11(4): 560-581. DOI: 10.1175/1520-0434(1996)011<0560:FFFAIB>2.0.CO;2
    [30]
    俞小鼎, 周小刚, 王秀明. 雷暴与强对流临近天气预报技术进展. 气象学报, 2012, 70(3): 311-337.

    Yu X D, Zhou X G, Wang X M. The advances in the nowcasting techniques on thunderstorms and severe convection. Acta Meteor Sinica, 2012, 70(3): 311-337.
    [31]
    朱红芳, 王东勇, 杨祖祥, 等. "海葵"台风(1211号)暴雨雨滴谱特征分析. 暴雨灾害, 2020, 39(2): 167-175.

    Zhu H F, Wang D Y, Yang Z X, et al. Analysis of raindrop spectrum characteristics for a heavy rain event caused by Typhoon Haikui(No. 1211) in Anhui. Torrential Rain Disasters, 2020, 39(2): 167-175.
    [32]
    俞小鼎. 短时强降水临近预报的思路与方法. 暴雨灾害, 2013, 32(3): 202-209.

    Yu X D. Nowcasting thinking and method of flash heavy rain. Torrential Rain Disasters, 2013, 32(3): 202-209.
    [33]
    郑永光, 周康辉, 盛杰, 等. 强对流天气监测预报预警技术进展. 应用气象学报, 2015, 26(6): 641-657. DOI: 10.11898/1001-7313.20150601

    Zheng Y G, Zhou K H, Sheng J, et al. Advances in techniques of monitoring, forecasting and warning of severe convective weather. J Appl Meteor Sci, 2015, 26(6): 641-657. DOI: 10.11898/1001-7313.20150601
    [34]
    高洋, 蔡淼, 曹治强, 等. "21·7"河南暴雨环境场及云的宏微观特征. 应用气象学报, 2022, 33(6): 682-695. DOI: 10.11898/1001-7313.20220604

    Gao Y, Cai M, Cao Z Q, et al. Environmental conditions and cloud macro and micro features of "21·7" extreme heavy rainfall in Henan Province. J Appl Meteor Sci, 2022, 33(6): 682-695. DOI: 10.11898/1001-7313.20220604
    [35]
    陈刚, 赵坤, 吕迎辉, 等. 河南"21·7"特大暴雨过程微物理特征变化分析. 中国科学(地球科学), 2022, 52(10): 1887-1904.

    Chen G, Zhao K, Lu Y, et al. Variability of microphysical characteristics in the "21·7" Henan extremely heavy rainfall event. Sci China(Earth Sci), 2022, 65(10): 1861-1878.
    [36]
    张哲, 戚友存, 李东欢, 等. 2021年郑州"7·20"极端暴雨雨滴谱特征及其对雷达定量降水估测的影响. 大气科学, 2022, 46(4): 1002-1016.

    Zhang Z, Qi Y C, Li D H, et al. Raindrop size distribution characteristics of the extreme rainstorm event in Zhengzhou 20 July, 2021 and its impacts on radar quantitative precipitation estimation. Chinese J Atmos Sci, 2022, 46(4): 1002-1016.
    [37]
    Bringi V N, Chandrasekar V. Polarimetric Doppler Weather Radar. Cambridge: Cambridge University Press, 2001.
    [38]
    Ma Y, Ni G H, Chandra C V, et al. Statistical characteristics of raindrop size distribution during rainy seasons in the Beijing urban area and implications for radar rainfall estimation. Hydrol Earth Syst Sci, 2019, 23(10): 4153-4170.
    [39]
    苟阿宁, 吴翠红, 王玉娟, 等. 基于风廓线雷达的湖北梅雨期暴雨中小尺度特征. 干旱气象, 2022, 40(1): 84-94.

    Gou A N, Wu C H, Wang Y J, et al. Meso and small-scale characteristics of heavy rain during Meiyu period in Hubei based on wind profile radar. J Arid Meteor, 2022, 40(1): 84-94.
    [40]
    廖菲, 邓华, 侯灵. 降水条件下风廓线雷达数据质量分析及处理. 热带气象学报, 2016, 32(5): 588-595.

    Liao F, Deng H, Hou L. The effect assessment of wind field inversion based on WPR in precipitation. J Trop Meteor, 2016, 32(5): 588-595.
  • Cited by

    Periodical cited type(9)

    1. 许一洲,李国平,张晓玉,谢新,董元昌. 四川盆地一次暴雨过程与重力波的关联特征. 应用气象学报. 2025(01): 65-76 . 本站查看
    2. 任菊章,杨雪,陶云,付志嘉,陈艳,钟亚含,王曼,金燕. 冬季横断山区一次低空风切变诊断及模拟. 应用气象学报. 2025(01): 77-89 . 本站查看
    3. 刘媛媛,李敏,郝晓丽,刘业森,刘舒,俞茜. 不同类型城市洪涝风险成因分析及应对措施探讨. 中国防汛抗旱. 2025(02): 42-45+52 .
    4. 钟霈雯,陈耀登,谢彦辉,陈敏,范水勇,李娟. 微波辐射资料同化对华北“23·7”极端暴雨预报影响. 应用气象学报. 2025(02): 142-154 . 本站查看
    5. 邱贵强,武永利,董春卿,孙颖姝,马丽. 太行山中南段暖季极端降水的水汽输送特征. 应用气象学报. 2024(03): 285-297 . 本站查看
    6. 赵文芳,王蕙莹,孟慧芳,缪宇鹏,黄明明,范敏,唐伟. 省级降水实况分析产品在北京地区的适用性评估. 应用气象学报. 2024(03): 361-372 . 本站查看
    7. 冯晋勤,潘佳文,何清芳,赖巧珍. 极端持续性强降水过程雷达偏振量特征及演变. 应用气象学报. 2024(05): 577-589 . 本站查看
    8. 张紫怡,罗亦泳,曹志德,陈枫. 基于GNSS-PWV的深圳地区一次暴雨时空变化特征分析. 江西科学. 2024(06): 1271-1278 .
    9. 董良淼,刘国忠,翟舒楠,陈飞盛,梁存桂,唐文. 2024年广西暴雨天气及极端性分析. 气象研究与应用. 2024(04): 1-8 .

    Other cited types(3)

Catalog

    Figures(12)

    Article views998 PDF downloads363 Cited by: 12
    • Received : 2023-11-12
    • Accepted : 2023-12-18
    • Published : 2024-01-30

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return