The summer moisture transport by the large-scale circulation over China has been investigated using ECMWF–WMO twice-daily analyses for the period 1980–96. The horizontal flux of atmospheric water vapor and its divergence has been calculated over two target regions, namely, southeast China (25°–35°N, 110°–120°E) and northeast China (40°–50°N, 120°–130°E). The time-averaged fluxes show the southeastern Asian and Indian monsoon circulations bringing abundant moisture from the South China Sea and the Bay of Bengal, respectively, to southeast China while the midlatitude westerlies dominate the moisture transport over northeast China. The association between the interannual variations of moisture flux and rainfall over China has been examined. The comparison of the fluxes for wet and dry years over the southeast showed there to be, for the former, much stronger moisture transport by the southeastern Asian monsoon through the southern boundary but little change associated with transport by the Indian mo... Abstract The summer moisture transport by the large-scale circulation over China has been investigated using ECMWF–WMO twice-daily analyses for the period 1980–96. The horizontal flux of atmospheric water vapor and its divergence has been calculated over two target regions, namely, southeast China (25°–35°N, 110°–120°E) and northeast China (40°–50°N, 120°–130°E). The time-averaged fluxes show the southeastern Asian and Indian monsoon circulations bringing abundant moisture from the South China Sea and the Bay of Bengal, respectively, to southeast China while the midlatitude westerlies dominate the moisture transport over northeast China. The association between the interannual variations of moisture flux and rainfall over China has been examined. The comparison of the fluxes for wet and dry years over the southeast showed there to be, for the former, much stronger moisture transport by the southeastern Asian monsoon through the southern boundary but little change associated with transport by the Indian mo...