• Ai, Y. F., W. B. Li, Z. Y. Meng, and J. Li, 2016: Life cycle characteristics of MCSs in middle east China tracked by geostationary satellite and precipitation estimates. Mon. Wea. Rev., 144, 25172530, https://doi.org/10.1175/MWR-D-15-0197.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Anderson, C. J., and R. W. Arritt, 1998: Mesoscale convective complexes and persistent elongated convective systems over the United States during 1992 and 1993. Mon. Wea. Rev., 126, 578599, https://doi.org/10.1175/1520-0493(1998)126<0578:MCCAPE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Augustine, J. A., and K. W. Howard, 1988: Mesoscale convective complexes over the United States during 1985. Mon. Wea. Rev., 116, 685701, https://doi.org/10.1175/1520-0493(1988)116<0685:MCCOTU>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Augustine, J. A., and K. W. Howard, 1991: Mesoscale convective complexes over the United States during 1986 and 1987. Mon. Wea. Rev., 119, 15751589, https://doi.org/10.1175/1520-0493(1991)119<1575:MCCOTU>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Banta, R. M., and C. B. Schaaf, 1987: Thunderstorm genesis zones in the Colorado Rocky Mountains as determined by traceback of geosynchronous satellite images. Mon. Wea. Rev., 115, 463476, https://doi.org/10.1175/1520-0493(1987)115<0463:TGZITC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bao, X. H., and F. Q. Zhang, 2013: Impacts of the mountain-plains solenoid and cold pool dynamics on the diurnal variation of precipitation over Northern China. Atmos. Chem. Phys., 13, 69656982, https://doi.org/10.5194/acp-13-6965-2013.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Blamey, R. C., and C. J. Reason, 2013: The role of mesoscale convective complexes in southern Africa summer rainfall. J. Climate, 26, 16541668, https://doi.org/10.1175/JCLI-D-12-00239.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, Y., Y. H. Ding, Z. N. Xiao, and H. M. Yan, 2006: The impact of water vapor transport on the summer monsoon onset and abnormal rainfall over Yunnan province in May (in Chinese). Chin. J. Atmos. Sci., 30, 2537.

    • Search Google Scholar
    • Export Citation
  • Coniglio, M. C., J. Y. Hwang, and D. J. Stensrud, 2010: Environmental factors in the upscale growth and longevity of MCSs derived from rapid update cycle analyses. Mon. Wea. Rev., 138, 35143539, https://doi.org/10.1175/2010 MWR3233.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cotton, W. R., M. S. Lin, R. L. McAnelly, and C. J. Tremback, 1989: A composite model of mesoscale convective complexes. Mon. Wea. Rev., 117, 765783, https://doi.org/10.1175/1520-0493(1989)117<0765:ACMOMC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Durkee, J. D., and T. L. Mote, 2010: A climatology of warm-season mesoscale convective complexes in subtropical South America. Int. J. Climatol., 30, 418431, https://doi.org/10.1002/JOC.1893.

    • Search Google Scholar
    • Export Citation
  • Feng, Z., X. Q. Dong, B. K. Xi, S. A. McFarlane, A. Kennedy, B. Lin, and P. Minnis, 2012: Life cycle of midlatitude deep convective systems in a Lagrangian framework. J. Geophys. Res., 117, D23201, https://doi.org/10.1029/2012JD018362.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feng, Z., R. A. Houze, L. R. Leung, F. F. Song, J. Hardin, J. Y. Wang, W. I. Gustafson, and C. R. Homeyer, 2019: Spatiotemporal characteristics and large-scale environments of mesoscale convective systems east of the Rocky Mountains. J. Climate, 32, 73037328, https://doi.org/10.1175/JCLI-D-19-0137.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Goyens, C., D. Lauwaet, M. Schröder, M. Demuzere, and N. P. M. Van Lipzig, 2012: Tracking mesoscale convective systems in the Sahel: Relation between cloud parameters and precipitation. Int. J. Climatol., 32, 19211934, https://doi.org/10.1002/joc.2407.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hane, C. E., C. L. Ziegler, and H. B. Bluestein, 1993: Investigation of the dryline and convective storms initiated along the dryline: Field experiments during COPS-91. Bull. Amer. Meteor. Soc., 74, 21332145, https://doi.org/10.1175/1520-0477(1993)074<2133:IOTDAC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • He, Z. W., Q. H. Zhang, L. Q. Bai, and Z. Y. Meng, 2016: Characteristics of mesoscale convective systems in central East China and their reliance on atmospheric circulation patterns. Int. J. Climatol., 37, 32763290, https://doi.org/10.1002/joc.4917.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hersbach, H., and Coauthors, 2019: Global reanalysis: Goodbye ERA-Interim, hello ERA5. ECMWF Newsletter, No. 159, ECMWF, Reading, United Kingdom, 17–24, https://www.ecmwf.int/en/elibrary/19027-global-reanalysis-goodbye-era-interim-hello-era5.

  • Houze, R. A., 2012: Orographic effects on precipitating clouds. Rev. Geophys., 50, RG1001, https://doi.org/10.1029/2011RG000365.

  • Hu, L., D. F. Deng, S. T. Gao, and X. D. Xu, 2016: The seasonal variation of Tibetan convective systems: Satellite observation. J. Geophys. Res. Atmos., 121, 55125525, https://doi.org/10.1002/2015JD024390.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hu, L., D. F. Deng, X. D. Xu, and P. Zhao, 2017: The regional differences of Tibetan convective systems in boreal summer. J. Geophys. Res. Atmos., 122, 72897299, https://doi.org/10.1002/2017JD026681.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jiang, Z. H., R. Lu, and Y. G. Ding, 2013: Analysis of the high-resolution merged precipitation products over China based on the temporal and spatial structure score indices (in Chinese). Acta Meteor. Sin., 71, 891900.

    • Search Google Scholar
    • Export Citation
  • Jin, X., and J. W. Han, 2010: K-means clustering. Encyclopedia of Machine Learning. C. Sammut and G. I. Webb, Eds., Springer, 563–564, https://doi.org/10.1007/978-0-387-30164-8_425.

    • Crossref
    • Export Citation
  • Jirak, I. L., W. R. Cotton, and R. L. McAnelly, 2003: Satellite and radar survey of mesoscale convective system development. Mon. Wea. Rev., 131, 24282449, https://doi.org/10.1175/1520-0493(2003)131<2428:SARSOM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kondo, Y., A. Higuchi, and K. Nakamura, 2006: Small-scale cloud activity over the maritime continent and the western Pacific as revealed by satellite data. Mon. Wea. Rev., 134, 15811599, https://doi.org/10.1175/MWR3132.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kuo, J. T., and H. D. Orville, 1973: A radar climatology of summertime convective clouds in the Black Hills. J. Appl. Meteor., 12, 359368, https://doi.org/10.1175/1520-0450(1973)012<0359:ARCOSC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Laing, A. G., and J. M. Fritsch, 1997: The global population of mesoscale convective complexes. Quart. J. Roy. Meteor. Soc., 123, 389405, https://doi.org/10.1002/qj.49712353807.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lane, T. P., and M. W. Moncrieff, 2015: Long-lived mesoscale systems in a low–convective inhibition environment. Part I: Upshear propagation. J. Atmos. Sci., 72, 42974318, https://doi.org/10.1175/JAS-D-15-0073.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Laurent, H., L. A. T. Machado, C. A. Morales, and L. Durieux, 2002: Characteristics of the Amazonian mesoscale convective systems observed from satellite and radar during the WETAMC/LBA experiment. J. Geophys. Res., 107, 8054, https://doi.org/10.1029/2001JD000337.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, J., D. H. Wang, and B. Wang, 2012a: Structure characteristics of moist neutral stratification in a mesoscale convective system (in Chinese). Climatic Environ. Res., 17, 617627.

    • Search Google Scholar
    • Export Citation
  • Li, J., B. Wang, and D. H. Wang, 2012b: The characteristics of mesoscale convective systems (MCSs) over East Asia in warm seasons. Atmos. Ocean. Sci. Lett., 5, 102107, https://doi.org/10.1080/16742834.2012.11446973.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, J. Y., X. Y. Shen, D. H. Wang, and J. Li, 2015: Distribution and characteristic of the MCS over South China during the spring and summer of 2008 (in Chinese). J. Trop. Meteor., 31, 475485.

    • Search Google Scholar
    • Export Citation
  • Liao, J., B. Xu, and H. Z. Zhang, 2013: Assessment of experiment of merging gauge observations with CMORPH (in Chinese). J. Trop. Meteor., 29, 163171.

    • Search Google Scholar
    • Export Citation
  • Lloyd, S. P., 1982: Least squares quantization in PCM. IEEE Trans. Inf. Theory, 28, 129137, https://doi.org/10.1109/TIT.1982.1056489.

  • MacQueen, J. B., 1967: Some methods for classification and analysis of multivariate observations. Proceedings of the Fifth Berkeley Symposium on Mathematical Statistics and Probability, Vol. 1, L. M. Le Cam and J. Neyman, Eds., University of California Press, 281–297, https://projecteuclid.org/euclid.bsmsp/1200512992.

  • Maddox, R. A., 1980: Mesoscale convective complexes. Bull. Amer. Meteor. Soc., 61, 13741387, https://doi.org/10.1175/1520-0477(1980)061<1374:MCC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Maddox, R. A., 1983: Large-scale meteorological conditions associated with midlatitude, mesoscale convective complexes. Mon. Wea. Rev., 111, 14751493, https://doi.org/10.1175/1520-0493(1983)111<1475:LSMCAW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mai, Z., S. M. Fu, and J. H. Sun, 2019: Statistical features of two types of mesoscale convective systems (MCSs) generated over the eastern Tibetan Plateau during 16 warm seasons (in Chinese). Climatic Environ. Res., 25 (4), 385398.

    • Search Google Scholar
    • Export Citation
  • Mai, Z., S. M. Fu, J. H. Sun, and L. Hu, 2020: Key statistical characteristics of the mesoscale convective systems generated over the Tibetan Plateau and their relationship to precipitation and southwest vortices. Int. J. Climatol., https://doi.org/10.1002/joc.6735, in press.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mathon, V., and H. Laurent, 2001: Life cycle of Sahelian mesoscale convective cloud systems. Quart. J. Roy. Meteor. Soc., 127, 377406, https://doi.org/10.1002/qj.49712757208.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mathon, V., H. Laurent, and T. Lebel, 2002: Mesoscale convective system rainfall in the Sahel. J. Appl. Meteor., 41, 10811092, https://doi.org/10.1175/1520-0450(2002)041<1081:MCSRIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • McAnelly, R. L., and W. R. Cotton, 1992: Early growth of mesoscale convective complexes: A meso-β-scale cycle of convective precipitation? Mon. Wea. Rev., 120, 18511877, https://doi.org/10.1175/1520-0493(1992)120<1851:EGOMCC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meisner, B. N., and P. A. Arkin, 1987: Spatial and annual variations in the diurnal cycle of large-scale tropical convective cloudiness and precipitation. Mon. Wea. Rev., 115, 20092032, https://doi.org/10.1175/1520-0493(1987)115<2009:SAAVIT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pan, Y., Y. Shen, J. J. Yu, and P. Zhao, 2012: Analysis of the combined gauge-satellite hourly precipitation over China based on the OI technique (in Chinese). Acta Meteor. Sin., 70, 13811389.

    • Search Google Scholar
    • Export Citation
  • Parker, M. D., and R. H. Johnson, 2000: Organizational modes of midlatitude mesoscale convective systems. Mon. Wea. Rev., 128, 34133436, https://doi.org/10.1175/1520-0493(2001)129<3413:OMOMMC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pope, M., C. Jakob, and M. J. Reeder, 2008: Convective systems of the north Australian monsoon. J. Climate, 21, 50915112, https://doi.org/10.1175/2008JCLI2304.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Punkka, A. J., and M. Bister, 2015: Mesoscale convective systems and their synoptic-scale environment in Finland. Wea. Forecasting, 30, 182196, https://doi.org/10.1175/WAF-D-13-00146.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Purdom, J. F. W., and K. Marcus, 1982: Thunderstorm trigger mechanism over the southeast U.S. Preprints, 12th Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., 487–488.

  • Rafati, S., and M. Karimi, 2017: Assessment of mesoscale convective systems using IR brightness temperature in the southwest of Iran. Theor. Appl. Climatol., 129, 539549, https://doi.org/10.1007/s00704-016-1797-7.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schumacher, R. S., and R. H. Johnson, 2005: Organization and environmental properties of extreme rain producing mesoscale convective systems. Mon. Wea. Rev., 133, 961976, https://doi.org/10.1175/MWR2899.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shen, Y., P. Yang, J. J. Yu, P. Zhao, and Z. J. Zhou, 2013: Quality assessment of hourly merged precipitation product over China (in Chinese). Daqi Kexue Xuebao, 36, 3746.

    • Search Google Scholar
    • Export Citation
  • Song, F. F., Z. Feng, L. R. Leung, R. A. Houze, J. Y. Wang, J. Hardin, and C. R. Homeyer, 2019: Contrasting spring and summer large-scale environments associated with mesoscale convective systems over the U.S. Great Plains. J. Climate, 32, 67496767, https://doi.org/10.1175/JCLI-D-18-0839.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sun, J. H., and Q. F. Zhang, 2012: Impacts of mountain–plains solenoid on diurnal variations of rainfalls along the mei-yu front over the East China plains. Mon. Wea. Rev., 140, 379397, https://doi.org/10.1175/MWR-D-11-00041.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sun, J. H., L. L. Zheng, and S. X. Zhao, 2014: Impact of moisture on the organizational mode and intensity of squall lines determined through numerical experiments (in Chinese). Chin. J. Atmos. Sci., 38, 742755.

    • Search Google Scholar
    • Export Citation
  • Takemi, T., 2007: Environmental stability control of the intensity of squall lines under low-level shear conditions. J. Geophys. Res., 112, D24110, https://doi.org/10.1029/2007JD008793.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Tao, S. Y., 1980: Heavy Rainfalls in China (in Chinese). Science Press, 255 pp.

  • Tollerud, E. I., J. Augustine, and B. D. Jamison, 1992: Cloud top characteristics of mesoscale convective systems in 1986. Preprints, Sixth Conf. on Satellite Meteorology and Oceanography, Atlanta, GA, Amer. Meteor. Soc., J3–J7.

  • USGS, 2003: Global 30-arc-second elevation data set (GTOPO30). U.S. Geological Survey, accessed 22 December 2019, https://doi.org/10.5066/F7DF6PQS.

    • Crossref
    • Export Citation
  • Wang, S. L., H. W. Kang, X. Q. Gu, and Y. Q. Ni, 2015: Numerical simulation of mesoscale convective system in the warm sector of Beijing “7.21” severe rainstorm (in Chinese). Meteor. Mon., 41, 544553.

    • Search Google Scholar
    • Export Citation
  • Wilson, J. W., G. B. Foote, N. A. Crook, J. C. Fankhauser, C. G. Wade, J. D. Tuttle, and C. K. Mueller, 1992: The role of boundary-layer convergence zones and horizontal rolls in the initiation of thunderstorms: A case study. Mon. Wea. Rev., 120, 17851815, https://doi.org/10.1175/1520-0493(1992)120<1785:TROBLC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xie, L., and K. Ueno, 2011: Differences of synoptic fields depending on the location of MCS genesis in southwest China. Tsukuba Geoenviron. Sci., 7, 3–12, http://hdl.handle.net/2241/116870.

  • Xu, W. X., 2013: Precipitation and convective characteristics of summer deep convection over East Asia observed by TRMM. Mon. Wea. Rev., 141, 15771592, https://doi.org/10.1175/MWR-D-12-00177.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xu, X. D., S. Y. Tao, J. Z. Wang, L. S. Chen, L. Zhou, and X. R. Wang, 2002: The relationship between water vapor transport features of Tibetan Plateau-Monsoon “large triangle” affecting region and drought-flood abnormality of China (in Chinese). Acta Meteor. Sin., 60, 257266.

    • Search Google Scholar
    • Export Citation
  • Yang, Q., R. A. Houze, L. R. Leung, and Z. Feng, 2017: Environments of long-lived mesoscale convective systems over the central United States in convection permitting climate simulations. J. Geophys. Res. Atmos., 122, 13 28813 307, https://doi.org/10.1002/2017JD027033.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, R. Y., Y. C. Zhang, J. H. Sun, S. M. Fu, and J. Li, 2018: The characteristics and classification of eastward-propagating mesoscale convective systems generated over the second-step terrain in the Yangtze River Valley. Atmos. Sci. Lett., 20, e874, https://doi.org/10.1002/asl.874.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, R. Y., Y. C. Zhang, J. H. Sun, and J. Li, 2020: The comparison of statistical features and synoptic circulations between the eastward-propagating and quasi-stationary MCSs during the warm season around the second-step terrain along the middle reaches of the Yangtze River. Sci. China Earth Sci., 63, 12091222, https://doi.org/10.1007/s11430-018-9385-3.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, X. R., J. F. Fei, X. G. Huang, X. P. Cheng, L. M. Carvalho, and H. R. He, 2015: Characteristics of mesoscale convective systems over China and its vicinity using geostationary satellite FY2. J. Climate, 28, 48904907, https://doi.org/10.1175/JCLI-D-14-00491.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhang, M. M., and Z. H. Jiang, 2013: Analyses of high-resolution merged precipitation products over China (in Chinese). Climatic Environ. Res., 18, 461471.

    • Search Google Scholar
    • Export Citation
  • Zheng, L. L., and J. H. Sun, 2013: Characteristics of synoptic and surface circulation of mesoscale convective systems in dry and moist environmental conditions (in Chinese). Chin. J. Atmos. Sci., 37, 891904.

    • Search Google Scholar
    • Export Citation
  • Zheng, L. L., J. H. Sun, X. L. Zhang, and C. H. Liu, 2013: Organizational modes of mesoscale convective systems over central east China. Wea. Forecasting, 28, 10811098, https://doi.org/10.1175/WAF-D-12-00088.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zheng, Y. G., and J. Chen, 2013: A climatology of deep convection over South China and the adjacent waters during summer. J. Trop. Meteor., 19, 115.

    • Search Google Scholar
    • Export Citation
  • Zheng, Y. G., J. Chen, and P. J. Zhu, 2008: Climatological distribution and diurnal variation of mesoscale convective systems over China and its vicinity during summer. Chin. Sci. Bull., 53, 15741586, https://doi.org/10.1007/s11434-008-0116-9.

    • Search Google Scholar
    • Export Citation
  • Zheng, Y. G., M. Xue, B. Li, J. Chen, and Z. Y. Tao, 2016: Spatial characteristics of extreme rainfall over China with hourly through 24-hour accumulation periods based on national-level hourly rain gauge data. Adv. Atmos. Sci., 33, 12181232, https://doi.org/10.1007/s00376-016-6128-5.

    • Crossref
    • Search Google Scholar
    • Export Citation
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A 10-Year Climatology of Mesoscale Convective Systems and Their Synoptic Circulations in the Southwest Mountain Area of China

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  • 1 Key Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
  • 2 University of Chinese Academy of Sciences, Beijing, China
  • 3 Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
  • 4 International Center for Climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
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Abstract

Hourly blackbody temperature data from the warm seasons (May–September) of 2009–18 were used to detect mesoscale convective systems (MCSs) generated in the southwest mountain area (elevation ≥ 500 m) of China. A total of 3059 MCSs were grouped into four categories (C1, C2, C3, and C4) according to their generation positions using K-means clustering. Major characteristics of the four types of MCSs and their synoptic environmental conditions were investigated. The MCSs had a peak in July and a minimum in May, and usually lasted from 3 to 21 h. The C1 MCSs generated in the northeast of the Tibetan Plateau developed faster, were largest, and had a longer lifespan. The C2 and C4 MCSs had greater intensity and were initiated in the southeast of the Tibetan Plateau and the west of the Yungui Plateau, and near the Wuling and Xuefeng Mountains, respectively. The C3 MCSs initiated in the Qinling, Ta-pa, and Wushan Mountains were smallest. The C1 and C2 MCSs contributed more than 30% to total precipitation, which was more than the C3 and C4 MCSs (<25%), and the contribution rate of MCSs to short-duration heavy rainfall affected by local MCSs was over 60%. Composite synoptic circulations of the four types of MCSs showed several factors, including the locations and intensities of cyclones in the Bay of Bengal and high pressure in the Indochina Peninsula in the low-to-middle troposphere, and vortexes or southwesterly winds in the low-level troposphere, regulate the location and intensity of convection.

© 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Jianhua Sun, sjh@mail.iap.ac.cn

Abstract

Hourly blackbody temperature data from the warm seasons (May–September) of 2009–18 were used to detect mesoscale convective systems (MCSs) generated in the southwest mountain area (elevation ≥ 500 m) of China. A total of 3059 MCSs were grouped into four categories (C1, C2, C3, and C4) according to their generation positions using K-means clustering. Major characteristics of the four types of MCSs and their synoptic environmental conditions were investigated. The MCSs had a peak in July and a minimum in May, and usually lasted from 3 to 21 h. The C1 MCSs generated in the northeast of the Tibetan Plateau developed faster, were largest, and had a longer lifespan. The C2 and C4 MCSs had greater intensity and were initiated in the southeast of the Tibetan Plateau and the west of the Yungui Plateau, and near the Wuling and Xuefeng Mountains, respectively. The C3 MCSs initiated in the Qinling, Ta-pa, and Wushan Mountains were smallest. The C1 and C2 MCSs contributed more than 30% to total precipitation, which was more than the C3 and C4 MCSs (<25%), and the contribution rate of MCSs to short-duration heavy rainfall affected by local MCSs was over 60%. Composite synoptic circulations of the four types of MCSs showed several factors, including the locations and intensities of cyclones in the Bay of Bengal and high pressure in the Indochina Peninsula in the low-to-middle troposphere, and vortexes or southwesterly winds in the low-level troposphere, regulate the location and intensity of convection.

© 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Jianhua Sun, sjh@mail.iap.ac.cn
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