Rainfall data were kindly provided by the Thai Meteorological Department. We thank Dr. H. Fujinami of Nagoya University for his thoughtful discussions and comments. We thank Prof. B. Wang of the University of Hawaii for valuable comments and suggestions. We are grateful to Prof. J. Matsumoto of the University of Tokyo for valuable comments. Some figures were made with the Generic Mapping Tools (GMT) graphics system developed by Wessel and Smith in 1995. This study was supported by Dynamics of the Sun-Earth-Life Interactive System, No. G-4, of the 21st Century COE program.
Harr, P. A., , and R. L. Elsberry, 1991: Tropical cyclone track characteristics as a function of large-scale circulation anomalies. Mon. Wea. Rev, 119 , 1448–1468.
Harr, P. A., , and R. L. Elsberry, 1995: Large-scale circulation variation over the tropical western North Pacific. Part I: Spatial patterns and tropical cyclone characteristics. Mon. Wea. Rev, 123 , 1225–1246.
He, H., , W. McGinnis, , Z. Song, , and M. Yanai, 1987: Onset of the Asian summer monsoon in 1979 and the effect of the Tibetan Plateau. Mon. Wea. Rev, 115 , 1966–1995.
Jiang, X., , T. Li, , and B. Wang, 2004: Structures and mechanisms of the northward propagating boreal summer intraseasonal oscillation. J. Climate, 17 , 1022–1039.
Kang, I-S., , C-H. Ho, , Y-K. Lim, , and K-M. Lau, 1999: Principal modes of climatological, seasonal, and intraseasonal variations of the Asian summer monsoon. Mon. Wea. Rev, 127 , 322–340.
Kato, K., 1985: On the abrupt change in the structure of the baiu front over the China Continent in late May of 1979. J. Meteor. Soc. Japan, 63 , 737–750.
Kawamura, R., , and T. Murakami, 1998: Baiu near Japan and its relation to summer monsoons over Southeast Asia and the western North Pacific. J. Meteor. Soc. Japan, 76 , 619–639.
Krishnamurti, T. N., , and P. Ardanuy, 1980: The 10 to 20-day westward propagation mode and “breaks in the monsoons.”. Tellus, 32 , 15–26.
Lau, K-M., , G. J. Yang, , and S. H. Shen, 1988: Seasonal and intraseasonal climatology of summer monsoon rainfall over East China. Mon. Wea. Rev, 116 , 18–37.
LinHo, and Wang, B., 2002: The time–space structure of the Asian–Pacific summer monsoon: A fast annual cycle view. J. Climate, 15 , 2001–2019.
Matsumoto, J., 1997: Seasonal transition of summer rainy season over Indochina and adjacent monsoon region. Adv. Atmos. Sci, 14 , 231–245.
Murakami, T., , and J. Matsumoto, 1994: Summer monsoon over the Asian Continent and Western North Pacific. J. Meteor. Soc. Japan, 72 , 719–745.
Nakazawa, T., 1992: Seasonal phase lock of intraseasonal variation during the Asian summer monsoon. J. Meteor. Soc. Japan, 70 , 597–611.
Ninomiya, K., , and H. Muraki, 1986: Large-scale circulation over East Asia during Baiu period 1979. J. Meteor. Soc. Japan, 64 , 409–429.
Nitta, T., 1987: Convective activities in the tropical western Pacific and their impacts on the Northern Hemisphere summer circulation. J. Meteor. Soc. Japan, 65 , 373–390.
Rao, Y., 1976: Southwest Monsoons. Meteor. Monogr., No. 1, Indian Meteorological Department, 367 pp.
Tao, S., , and L. Chen, 1987: A review of recent research on the East Asian summer monsoon in China. Monsoon Meteorology, C.-P. Chan and T. N. Krishnamurti, Eds., Oxford University Press, 60–92.
Ueda, H., , and T. Yasunari, 1996: Maturing process of the summer monsoon over the Western North Pacific—A coupled ocean/atmosphere system. J. Meteor. Soc. Japan, 74 , 493–508.
Ueda, H., , T. Yasunari, , and R. Kawamura, 1995: Abrupt seasonal change of large-scale convection activity over the western Pacific in northern summer. J. Meteor. Soc. Japan, 73 , 795–809.
Wang, B., , and X. Xu, 1997: Northern Hemisphere summer monsoon singularities and climatological intraseasonal oscillation. J. Climate, 10 , 1071–1085.
Wu, R., , and B. Wang, 2000: Interannual variability of summer monsoon onset over the western North Pacific and the underlying processes. J. Climate, 13 , 2483–2501.
Xie, P., , and P. Arkin, 1997: Global precipitation: A 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bull. Amer. Meteor. Soc, 78 , 2539–2558.
Yasunari, T., 1979: Cloudiness fluctuations associated with the northern hemisphere summer monsoon. J. Meteor. Soc. Japan, 57 , 227–242.
Yasunari, T., 1980: A quasi-stationary appearance of 30- to 40-day period in the cloudiness fluctuations during the summer monsoon over India. J. Meteor. Soc. Japan, 58 , 225–229.
Zhang, Y., , T. Li, , B. Wang, , and G. Wu, 2002: Onset of the summer monsoon over the Indochina Peninsula: Climatology and interannual variations. J. Climate, 15 , 3206–3221.