Synoptic Conditions Associated with Propagating and Nonpropagating Cloud/Rainfall Episodes during the Warm Season over the East Asian Continent

Chung-Chieh Wang Department of Earth Sciences, National Taiwan Normal University, Taipei, Taiwan

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George Tai-Jen Chen Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan

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Hsiao-Ling Huang Department of Atmospheric Sciences, National Taiwan University, Taipei, Taiwan

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Richard E. Carbone National Center for Atmospheric Research, Boulder, Colorado

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Sau-Wa Chang Macau Meteorological and Geophysical Bureau, Macau, China

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Abstract

Using European Centre for Medium-Range Weather Forecasts (ECMWF) analyses, this study identifies common synoptic flow patterns associated with propagating (long lived) and nonpropagating (short lived) precipitation/cloud episodes in the warm season over East Asia (25°–40°N, 95°–125°E). Among 123 initial cases during May–July 1997–2003, 86 were classified into three categories (propagating cases with strong and weak forcing, and nonpropagating ones with strong inhibition) consisting of 10 types based on their 500-hPa flow patterns. For each type, composites at various levels when episodes moved across 100°, 105°, 110°, 115°, and 120°E were made and discussed to elucidate the influence of synoptic conditions.

For propagating episodes with strong 500-hPa forcing (46 cases), four types were identified. In their composites, favorable positive vorticity advection forcing from an approaching trough/short wave exists aloft, and concurrent development of southwest vortex and front/wind-shift line at low levels leads to enhanced southwesterly flow to provide vertical shear and moisture. For nonpropagating episodes with strong inhibition (25 cases), three types dominated by synoptic-scale subsidence from either negative vorticity advection or the subtropical high were identified. Thus, episodes weaken shortly after they move out from the Tibetan Plateau. There are also propagating episodes but with weak forcing (15 cases), for which another three types were found. The differences in their composites from nonpropagating types are mainly at low levels, where the southerly flow is stronger and can penetrate deeper inland. As stability conditions are similar for all type of episodes, the results suggest an important role of stronger low-level southwesterly winds in providing moisture and vertical wind shear to sustain episodes and their propagation.

Corresponding author address: Prof. George Tai-Jen Chen, Dept. of Atmospheric Sciences, National Taiwan University, No. 61, Ln. 144, Sec. 4, Keelung Rd., Taipei 10772, Taiwan. E-mail: george@as.ntu.edu.tw

Abstract

Using European Centre for Medium-Range Weather Forecasts (ECMWF) analyses, this study identifies common synoptic flow patterns associated with propagating (long lived) and nonpropagating (short lived) precipitation/cloud episodes in the warm season over East Asia (25°–40°N, 95°–125°E). Among 123 initial cases during May–July 1997–2003, 86 were classified into three categories (propagating cases with strong and weak forcing, and nonpropagating ones with strong inhibition) consisting of 10 types based on their 500-hPa flow patterns. For each type, composites at various levels when episodes moved across 100°, 105°, 110°, 115°, and 120°E were made and discussed to elucidate the influence of synoptic conditions.

For propagating episodes with strong 500-hPa forcing (46 cases), four types were identified. In their composites, favorable positive vorticity advection forcing from an approaching trough/short wave exists aloft, and concurrent development of southwest vortex and front/wind-shift line at low levels leads to enhanced southwesterly flow to provide vertical shear and moisture. For nonpropagating episodes with strong inhibition (25 cases), three types dominated by synoptic-scale subsidence from either negative vorticity advection or the subtropical high were identified. Thus, episodes weaken shortly after they move out from the Tibetan Plateau. There are also propagating episodes but with weak forcing (15 cases), for which another three types were found. The differences in their composites from nonpropagating types are mainly at low levels, where the southerly flow is stronger and can penetrate deeper inland. As stability conditions are similar for all type of episodes, the results suggest an important role of stronger low-level southwesterly winds in providing moisture and vertical wind shear to sustain episodes and their propagation.

Corresponding author address: Prof. George Tai-Jen Chen, Dept. of Atmospheric Sciences, National Taiwan University, No. 61, Ln. 144, Sec. 4, Keelung Rd., Taipei 10772, Taiwan. E-mail: george@as.ntu.edu.tw
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  • Ahijevych, D. A., C. A. Davis, R. E. Carbone, and J. D. Tuttle, 2004: Initiation of precipitation episodes relative to elevated terrain. J. Atmos. Sci., 61, 27632769.

    • Search Google Scholar
    • Export Citation
  • Asai, T., S. Ke, and Y.-M. Kodama, 1998: Diurnal variability of cloudiness over East Asia and the western Pacific Ocean as revealed by GMS during the warm season. J. Meteor. Soc. Japan, 76, 675684.

    • 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.

    • Search Google Scholar
    • Export Citation
  • Bao, X., F. Zhang, and J. Sun, 2011: Diurnal variations of warm-season precipitation east of the Tibetan Plateau over China. Mon. Wea. Rev., 139, 27902810.

    • Search Google Scholar
    • Export Citation
  • Bluestein, H. B., 1993: Principles of Kinematics and Dynamics. Vol. 1, Synoptic–Dynamic Meteorology in Midlatitudes, Oxford Press, 431 pp.

    • Search Google Scholar
    • Export Citation
  • Carbone, R. E., and J. D. Tuttle, 2008: Rainfall occurrence in the U.S. warm season: The diurnal cycle. J. Climate, 21, 41324146.

  • Carbone, R. E., J. D. Tuttle, D. Ahijevych, and S. B. Trier, 2002: Inferences of predictability associated with warm season precipitation episodes. J. Atmos. Sci., 59, 20332056.

    • Search Google Scholar
    • Export Citation
  • Carlson, T. N., 1991: Mid-Latitude Weather Systems. Routledge, 507 pp.

  • Chen, G. T.-J., 1994: Large-scale circulations associated with the East Asian summer monsoon and the mei-yu over south China and Taiwan. J. Meteor. Soc. Japan, 72, 959983.

    • Search Google Scholar
    • Export Citation
  • Chen, G. T.-J., 2004: Research on the phenomena of meiyu during the past quarter century: An overview. The East Asian Monsoon, C.-P. Chang, Ed., World Scientific, 357–403.

    • Search Google Scholar
    • Export Citation
  • Chen, G. T.-J., and C.-C. Yu, 1988: Study of low-level jet and extremely heavy rainfall over northern Taiwan in the mei-yu season. Mon. Wea. Rev., 116, 884891.

    • Search Google Scholar
    • Export Citation
  • Chen, G. T.-J., and Y.-S. Hsu, 1997: Composite structure of a low-level jet over southern China observed during the TAMEX period. J. Meteor. Soc. Japan, 75, 10031018.

    • Search Google Scholar
    • Export Citation
  • Chen, G. T.-J., C.-C. Wang, and D. T.-W. Lin, 2005: Characteristics of low-level jets over northern Taiwan in mei-yu season and their relationship to heavy rain events. Mon. Wea. Rev., 133, 2043.

    • Search Google Scholar
    • Export Citation
  • Chen, H., R. Yu, J. Li, W. Yuan, and T. Zhou, 2010: Why nocturnal long-duration rainfall presents an eastward-delayed diurnal phase of rainfall down the Yangtze River valley? J. Climate, 23, 905917.

    • Search Google Scholar
    • Export Citation
  • Chen, T.-C., S.-Y. Wang, W.-R. Huang, and M.-C. Yen, 2004: Variation of the East Asian summer monsoon rainfall. J. Climate, 17, 744762.

    • Search Google Scholar
    • Export Citation
  • Chen, X. A., and Y. L. Chen, 1995: Development of low-level jets during TAMEX. Mon. Wea. Rev., 123, 16951719.

  • Colby, F. P., 1984: Convective inhibition as a predictor of convection during AVE-SESAME-2. Mon. Wea. Rev., 112, 22392252.

  • Davis, C. A., K. W. Manning, R. E. Carbone, S. B. Trier, and S. B. Tuttle, 2003: Coherence of warm-season continental rainfall in numerical weather prediction models. Mon. Wea. Rev., 131, 26672679.

    • Search Google Scholar
    • Export Citation
  • Ding, Y., 1992: Summer monsoon rainfalls in China. J. Meteor. Soc. Japan, 70, 373396.

  • Ding, Y., and J. C.-L. Chan, 2005: The East Asian summer monsoon: An overview. Meteor. Atmos. Phys., 89, 117142.

  • Doswell, C. A., III, 2001: Severe convective storms—An overview. Severe Convective Storms, Meteor. Monogr., No. 50, Amer. Meteor. Soc., 1–26.

    • Search Google Scholar
    • Export Citation
  • Doswell, C. A., III, and L. F. Bosart, 2001: Extratropical synoptic-scale processes and severe convection. Severe Convective Storms, Meteor. Monogr., No. 50, Amer. Meteor. Soc., 27–69.

    • Search Google Scholar
    • Export Citation
  • Fritsch, M. J., and R. E. Carbone, 2004: Improving quantitative precipitation forecasts in the warm season: A USWRP research and development strategy. Bull. Amer. Meteor. Soc., 85, 955965.

    • Search Google Scholar
    • Export Citation
  • He, H., and F. Zhang, 2010: Diurnal variations of warm-season precipitation over northern China. Mon. Wea. Rev., 138, 10171025.

  • Holton, J. R., 1967: The diurnal boundary layer wind oscillation above sloping terrain. Tellus, 19, 199205.

  • Huang, H.-L., C.-C. Wang, G. T.-J. Chen, and R. E. Carbone, 2010: The role of diurnal solenoidal circulation on propagating rainfall episodes near the eastern Tibetan Plateau. Mon. Wea. Rev., 138, 29752989.

    • Search Google Scholar
    • Export Citation
  • Huffman, G. J., and Coauthors, 2007: The TRMM multisatellite precipitation analysis: Quasi-global, multiyear, combined-sensor precipitation estimates at fine scale. J. Hydrometeor., 8, 3855.

    • Search Google Scholar
    • Export Citation
  • Johnson, R. H., 2011: Diurnal cycle of monsoon convection. The Global Monsoon System: Research and Forecast, C.-P. Chang et al., Eds., World Scientific, 257–276.

    • Search Google Scholar
    • Export Citation
  • Johnson, R. H., and B. E. Mapes, 2001: Mesoscale processes and severe convective weather. Severe Convective Storms, Meteor. Monogr., No. 50, Amer. Meteor. Soc., 71–122.

    • Search Google Scholar
    • Export Citation
  • Keenan, T. D., and R. E. Carbone, 2008: Propagation and diurnal evolution of warm season cloudiness in the Australian and maritime continent region. Mon. Wea. Rev., 136, 973994.

    • Search Google Scholar
    • Export Citation
  • Keyser, D., and M. A. Shapiro, 1986: A review of the structure and dynamics of upper-level frontal zones. Mon. Wea. Rev., 114, 452499.

    • Search Google Scholar
    • Export Citation
  • Kuo, Y.-H., L. Cheng, and R. A. Anthes, 1986: Mesoscale analysis of the Sichuan flood catastrophe. Mon. Wea. Rev., 114, 19842003.

  • Kuo, Y.-H., L. Cheng, and J.-W. Bao, 1988: Numerical simulation of the 1981 Sichuan flood. Part I: Evolution of the mesoscale southwest vortex. Mon. Wea. Rev., 116, 24812504.

    • 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.

    • Search Google Scholar
    • Export Citation
  • Laing, A. G., R. E. Carbone, V. Levizzani, and J. D. Tuttle, 2008: The propagation and diurnal cycles of deep convection in northern tropical Africa. Quart. J. Roy. Meteor. Soc., 134, 93109.

    • Search Google Scholar
    • Export Citation
  • Lau, K.-M., and M.-T. Li, 1984: The monsoon of East Asia and its global associations—A survey. Bull. Amer. Meteor. Soc., 65, 114125.

    • Search Google Scholar
    • Export Citation
  • Lau, K.-M., G. J. Yang, and S. H. Shen, 1988: Seasonal and intraseasonal climatology of summer monsoon rainfall over East Asia. Mon. Wea. Rev., 116, 1837.

    • Search Google Scholar
    • Export Citation
  • LeMone, M. A., E. J. Zipser, and S. B. Trier, 1998: The role of environmental shear and thermodynamic conditions in determining the structure and evolution of mesoscale convective systems during TOGA COARE. J. Atmos. Sci., 55, 34933518.

    • Search Google Scholar
    • Export Citation
  • Levizzani, V., F. Pinelli, M. Pasqui, S. Melani, A. G. Laing, and R. E. Carbone, 2010: A 10-year climatology of warm season cloud patterns over Europe and the Mediterranean from Meteosat IR observations. Atmos. Res., 97, 555576.

    • Search Google Scholar
    • Export Citation
  • Liu, C., M. W. Moncrieff, and J. D. Tuttle, 2008: A note on propagating rainfall episodes over the Bay of Bengal. Quart. J. Roy. Meteor. Soc., 134, 787792.

    • Search Google Scholar
    • Export Citation
  • Maddox, R. A., 1983: Large-scale meteorological conditions associated with mid-latitude mesoscale convective complexes. Mon. Wea. Rev., 111, 14751493.

    • Search Google Scholar
    • Export Citation
  • Pereira, A. J., R. E. Carbone, J. E. Janowiak, P. Arkin, R. Joyce, R. Hallak, and C. G. M. Ramos, 2010: Satellite rainfall estimates over South America—Possible applicability to the water management of large watersheds. J. Amer. Water Resour. Assoc., 46, 344360.

    • Search Google Scholar
    • Export Citation
  • Rotunno, R., J. B. Klemp, and M. L. Weisman, 1988: A theory for strong, long-lived squall lines. J. Atmos. Sci., 45, 463485.

  • Tao, S., and L. Chen, 1987: A review of recent research on the East Asian summer monsoon in China. Monsoon Meteorology, C.-P. Chang and T. N. Krishnamurti, Eds., Oxford University Press, 60–92.

    • Search Google Scholar
    • Export Citation
  • Trier, S. B., C. A. Davis, D. A. Ahijevych, and M. L. Weisman, 2006: Mechanisms supporting long-lived episodes of propagating nocturnal convection within a 7-day WRF model simulation. J. Atmos. Sci., 63, 24372461.

    • Search Google Scholar
    • Export Citation
  • Trier, S. B., C. A. Davis, and D. A. Ahijevych, 2010: Environmental controls on the simulated diurnal cycle of warm-season precipitation in the continental United States. J. Atmos. Sci., 67, 10661090.

    • Search Google Scholar
    • Export Citation
  • Tripoli, G. J., and W. R. Cotton, 1989a: Numerical study of an observed orogenic mesoscale convective system. Part I: Simulated genesis and comparison with observations. Mon. Wea. Rev., 117, 273304.

    • Search Google Scholar
    • Export Citation
  • Tripoli, G. J., and W. R. Cotton, 1989b: Numerical study of an observed orogenic mesoscale convective system. Part II: Analysis of governing dynamics. Mon. Wea. Rev., 117, 305328.

    • Search Google Scholar
    • Export Citation
  • Tuttle, J. D., and R. E. Carbone, 2004: Coherent regeneration and the role of water vapor and shear in a long-lived convective episode. Mon. Wea. Rev., 132, 192208.

    • Search Google Scholar
    • Export Citation
  • Tuttle, J. D., and C. A. Davis, 2006: Corridors of warm season precipitation in the central United States. Mon. Wea. Rev., 134, 22972317.

    • Search Google Scholar
    • Export Citation
  • Uccellini, L. W., 1990: Processes contributing to the rapid development of extratropical cyclones. Extratropical Cyclones—The Erik Palmén Memorial Volume, C. W. Newton and E. O. Holopainen, Eds., Amer. Meteor. Soc., 81–105.

    • Search Google Scholar
    • Export Citation
  • Wallace, J. M., 1975: Diurnal variations in precipitation and thunderstorm frequency over the conterminous United States. Mon. Wea. Rev., 103, 406419.

    • Search Google Scholar
    • Export Citation
  • Wang, B., and I. Orlanski, 1987: Study of a heavy rain vortex formed over the eastern flank of the Tibetan Plateau. Mon. Wea. Rev., 115, 13701393.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., G. T.-J. Chen, and R. E. Carbone, 2004: A climatology of warm-season cloud patterns over East Asia based on GMS infrared brightness temperature observations. Mon. Wea. Rev., 132, 16061629.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., G. T.-J. Chen, and R. E. Carbone, 2005: Variability of warm season cloud episodes over East Asia based on GMS infrared brightness temperature observations. Mon. Wea. Rev., 133, 14781500.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., G. T.-J. Chen, S.-C. Yang, and K. Tsuboki, 2009: Wintertime supercell thunderstorms in a subtropical environment: Numerical simulation. Mon. Wea. Rev., 137, 21752202.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., G. T.-J. Chen, and R. E. Carbone, 2011a: The relationship between statistics of warm-season cloud episodes and synoptic weather regimes over the East Asian continent. Meteor. Atmos. Phys., 112, 117124.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., G. T.-J. Chen, and S.-Y. Huang, 2011b: Remote trigger of deep convection by cold outflow over the Taiwan Strait in the mei-yu season: A modeling study of the 8 June 2007 case. Mon. Wea. Rev., 139, 28542875.

    • Search Google Scholar
    • Export Citation
  • Wang, C.-C., H.-L. Huang, J.-L. Li, T.-M. Leou, and G. T.-J. Chen, 2011c: An evaluation on the performance of the CWB NFS model in the prediction of warm-season rainfall distribution and propagation over the East Asian continent. Terr. Atmos. Oceanic Sci., 22, 4969, doi:10.3319/TAO.2010.07.13.01(A).

    • Search Google Scholar
    • Export Citation
  • Wang, W., Y.-H. Kuo, and T. T. Warner, 1993: A diabatically driven mesoscale vortex in the lee of the Tibetan Plateau. Mon. Wea. Rev., 121, 25422561.

    • Search Google Scholar
    • Export Citation
  • Xu, W., and E. J. Zipser, 2011: Diurnal variations of precipitation, deep convection, and lightning over and east of the eastern Tibetan Plateau. J. Climate, 24, 448465.

    • Search Google Scholar
    • Export Citation
  • Yu, R., T. Zhou, A. Xiong, Y. Zhu, and J. Li, 2007: Diurnal variations of summer precipitation over contiguous China. Geophys. Res. Lett., 34, L01704, doi:10.1029/2006GL028129.

    • Search Google Scholar
    • Export Citation
  • Zhong, S., J. D. Fast, and X. Bian, 1996: A case study of the Great Plains low-level jet using wind profiler network data and a high-resolution mesoscale model. Mon. Wea. Rev., 124, 785806.

    • Search Google Scholar
    • Export Citation
  • Zhou, T., R. Yu, H. Chen, A. Dai, and Y. Pan, 2008: Summer precipitation frequency, intensity, and diurnal cycle over China: A comparison of satellite data with rain gauge observations. J. Climate, 21, 39974010.

    • Search Google Scholar
    • Export Citation
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