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An analysis is made of the temporal and spatial characteristics of the circulation pattern at 500 hPa and vapor field at 700 hPa during the autumn waterlogging in upstream of the Han River in 2005 with NECP data. The results indicate that the height departure field at 500 hPa took on the wave train of “+, -, +". The primary sources of vapor at 700 hPa came from the Bay of Bengal and the South China Sea. The EOF analysis shows that the vapor flux divergence showed the same variation trend in upstream of the Han River and the Bay of Bengal and the South China Sea. The wavelet analysis reveals that the vapor flux divergence has oscillations of quasitwo week and quasione week in upstream of the Han River and the South China Sea. The strong precipitation appears frequently in the period of the superposed negative phase of several different frequency oscillations.