We thank Wasyl Drosdowsky for producing the Darwin onset dates and the daily gridded rainfall data. B. N. Goswami kindly provided us with the latest Kerala onset dates. The NCEP–NCAR reanalysis data were obtained from the NOAA Climate Diagnostics Center (CDC) (http://www.cdc.noaa.gov), and we thank John Janowiak of NCEP for his help in maintaining the daily updated OLR data.
Drosdowsky, W., and L. E. Chambers, 2001: Near-global sea surface temperature anomalies as predictors of Australian seasonal rainfall. J. Climate, 14 , 1677–1687.
Ferranti, L., T. N. Palmer, F. Molteni, and E. Klinker, 1990: Tropical– extratropical interaction associated with the 30–60 day oscillation and its impact on medium and extended range prediction. J. Atmos. Sci, 47 , 2177–2199.
Goswami, B. N., and R. S. Ajaya Mohan, 2001: Intraseasonal oscillations and interannual variability of the Indian summer monsoon. J. Climate, 14 , 1180–1198.
Gutzler, D. S., G. N. Kiladis, G. A. Meehl, K. M. Weickmann, and M. Wheeler, 1994: The global climate of December 1992–February 1993. Part II: Large-scale variability across the tropical western Pacific during TOGA COARE. J. Climate, 7 , 1606–1622.
Hall, J. D., A. J. Matthews, and D. J. Karoly, 2001: The modulation of tropical cyclone activity in the Australian region by the Madden–Julian oscillation. Mon. Wea. Rev, 129 , 2970–2982.
Hendon, H. H., 2000: Impact of air–sea coupling on the Madden– Julian oscillation in a general circulation model. J. Atmos. Sci, 57 , 3939–3952.
Hendon, H. H., and B. Liebmann, 1990a: A composite study of onset of the Australian summer monsoon. J. Atmos. Sci, 47 , 2227–2239.
Hendon, H. H., and B. Liebmann, 1990b: The intraseasonal (30–50 day) oscillation of the Australian summer monsoon. J. Atmos. Sci, 47 , 2909–2923.
Hendon, H. H., and B. Liebmann, 1994: Organization of convection within the Madden–Julian oscillation. J. Geophys. Res, 99 , 8073–8083.
Hendon, H. H., C. Zhang, and J. D. Glick, 1999: Interannual variation of the Madden–Julian osclliation during austral summer. J. Climate, 12 , 2538–2550.
Hendon, H. H., B. Liebmann, M. Newman, J. D. Glick, and J. E. Schemm, 2000: Medium-range forecast errors associated with active episodes of the Madden–Julian oscillation. Mon. Wea. Rev, 128 , 69–86.
Innes, P. M., and J. M. Slingo, 2003: Simulation of the Madden– Julian oscillation in a coupled general circulation model. Part I: Comparison with observations and an atmosphere-only GCM. J. Climate, 16 , 345–364.
Jones, C., 2000: Occurrence of extreme precipitation events in California and relationships with the Madden–Julian oscillation. J. Climate, 13 , 3576–3587.
Jones, C., D. E. Waliser, J-K. E. Schemm, and K-M. Lau, 2000: Prediction skill of the Madden and Julian oscillation in dynamical extended range forecasts. Climate Dyn, 16 , 273–289.
Joseph, P. V., J. K. Eischeid, and R. J. Pyle, 1994: Interannual variability of the onset of the Indian summer monsoon and its association with atmospheric features, El Niño, and sea surface temperature anomalies. J. Climate, 7 , 81–105.
Kemball-Cook, S., and B. Wang, 2001: Equatorial waves and air–sea interaction in the boreal summer intraseasonal oscillation. J. Climate, 14 , 2923–2942.
Kessler, W. S., 2001: EOF representation of the Madden–Julian oscillation and its connection with ENSO. J. Climate, 14 , 3055–3061.
Knutson, T. R., and K. M. Weickmann, 1987: 30–60 day atmospheric oscillations: Composite life cycles of convection and circulation anomalies. Mon. Wea. Rev, 115 , 1407–1436.
Kutzbach, J. E., 1967: Empirical eigenvectors of sea-level pressure, surface temperature and precipitation complexes over North America. J. Appl. Meteor, 6 , 791–802.
Lau, K-M., and P. H. Chan, 1985: Aspects of the 40–50 day oscillation during the northern winter as inferred from outgoing longwave radiation. Mon. Wea. Rev, 113 , 1889–1909.
Lawrence, D. M., and P. J. Webster, 2002: The boreal summer intraseasonal oscillation: Relationship between northward and eastward movement of convection. J. Atmos. Sci, 59 , 1593–1606.
Liebmann, B., and C. A. Smith, 1996: Description of a complete (interpolated) outgoing longwave radiation dataset. Bull. Amer. Meteor. Soc, 77 , 1275–1277.
Lo, F., and H. H. Hendon, 2000: Empirical extended-range prediction of the Madden–Julian oscillation. Mon. Wea. Rev, 128 , 2528–2543.
Lorenc, A. C., 1984: The evolution of planetary-scale 200 mb divergent flow during the FGGE year. Quart. J. Roy. Meteor. Soc, 110 , 427–441.
Madden, R. A., and P. R. Julian, 1972: Description of global-scale circulation cells in the Tropics with a 40–50 day period. J. Atmos. Sci, 29 , 1109–1123.
Maloney, E. D., and D. L. Hartmann, 1998: Frictional moisture convergence in a composite life cycle of the Madden–Julian oscillation. J. Climate, 11 , 2387–2403.
Maloney, E. D., and D. L. Hartmann, 2000: Modulation of eastern North Pacific hurricanes by the Madden–Julian oscillation. J. Climate, 13 , 1451–1460.
Maloney, E. D., and J. T. Kiehl, 2002: MJO-related SST variations over the tropical eastern Pacific during Northern Hemisphere summer. J. Climate, 15 , 675–689.
Matthews, A. J., and G. N. Kiladis, 1999: The tropical–extratropical interaction between high-frequency transients and the Madden–Julian oscillation. Mon. Wea. Rev, 127 , 661–677.
McBride, J. L., N. E. Davidson, K. Puri, and G. C. Tyrell, 1995: The flow during TOGA COARE as diagnosed by the BMRC Tropical Analysis and Prediction System. Mon. Wea. Rev, 123 , 718–736.
North, G. R., T. L. Bell, R. F. Cahalan, and F. J. Moeng, 1982: Sampling errors in the estimation of empirical orthogonal functions. Mon. Wea. Rev, 110 , 699–706.
Paegle, J. N., L. A. Byerle, and K. C. Mo, 2000: Intraseasonal modulation of South American summer precipitation. Mon. Wea. Rev, 128 , 837–850.
Salby, M. L., and H. H. Hendon, 1994: Intraseasonal behavior of clouds, temperature, and motion in the Tropics. J. Atmos. Sci, 51 , 2207–2224.
Slingo, J. M., D. P. Rowell, K. R. Sperber, and F. Nortley, 1999: On the predictability of the interannual behaviour of the Madden– Julian oscillation and its relationship with El Niño. Quart. J. Roy. Meteor. Soc, 125 , 583–609.
Sperber, K. R., J. M. Slingo, P. M. Innes, and W. K-M. Lau, 1997: On the maintenance and initiation of the intraseasonal oscillation in the NCEP/NCAR reanalysis and the GLA and UKMO AMIP simulations. Climate Dyn, 13 , 769–795.
von Storch, H., and J. Xu, 1990: Principal Oscillation Pattern analysis of the tropical 30–60 day oscillation. Part I: Definition of an index and its prediction. Climate Dyn, 4 , 179–190.
Waliser, D. E., C. Jones, J-K. E. Schemm, and N. E. Graham, 1999: A statistical extended-range tropical forecast model based on the slow evolution of the Madden–Julian oscillation. J. Climate, 12 , 1918–1939.
Waliser, D. E., K. M. Lau, W. Stern, and C. Jones, 2003: Potential predictability of the Madden–Julian oscillation. Bull. Amer. Meteor. Soc, 84 , 33–50.
Wang, B., and H. Rui, 1990: Dynamics of the coupled moist Kelvin– Rossby wave on an equatorial β-plane. J. Atmos. Sci, 47 , 397–413.
Webster, P. J., and R. Lukas, 1992: TOGA COARE: The Coupled Ocean–Atmosphere Response Experiment. Bull. Amer. Meteor. Soc, 73 , 1376–1416.
Weickmann, K. M., G. R. Lussky, and J. E. Kutzbach, 1985: Intraseasonal (30–60 day) fluctuations of outgoing longwave radiation and 250 mb streamfunction during northern winter. Mon. Wea. Rev, 113 , 941–961.
Wheeler, M., and G. N. Kiladis, 1999: Convectively coupled equatorial waves: Analysis of clouds and temperature in the wavenumber–frequency domain. J. Atmos. Sci, 56 , 374–399.
Wheeler, M., and K. M. Weickmann, 2001: Real-time monitoring and prediction of modes of coherent synoptic to intraseasonal tropical variability. Mon. Wea. Rev, 129 , 2677–2694.
Wheeler, M., G. N. Kiladis, and P. J. Webster, 2000: Large-scale dynamical fields associated with convectively coupled equatorial waves. J. Atmos. Sci, 57 , 613–640.
Whitaker, J. S., and K. M. Weickmann, 2001: Subseasonal variations of tropical convection and week-2 prediction of wintertime western North American rainfall. J. Climate, 14 , 3279–3288.
Yanai, M., B. Chen, and W-W. Tung, 2000: The Madden–Julian oscillation observed during the TOGA COARE IOP: Global view. J. Atmos. Sci, 57 , 2374–2396.
Zangvil, A., 1977: On the presentation and interpretation of spectra of large-scale disturbances. Mon. Wea. Rev, 105 , 1469–1472.
Zhang, C., and H. H. Hendon, 1997: Propagating and standing components of the intraseasonal oscillation in tropical convection. J. Atmos. Sci, 54 , 741–752.