Abstract:In the fall and winter of 2008 to 2009, a rare severe drought struck t welve provinces in East China. This severe drought is due to the lack of rainfal l for a sustained period. There was a quasi stationary circulation system in th e middle latitude over the Eurasia. There was a deep trough sustained over the n ortheast of Japan. In the Tibetan Plateau there was a stationary ridge. There wa s emulous cold air outbreak over the East China. Due to the persistence of the r idge over the plateau, the perturbations from West Asia could hardly reach East Asia. At the same time, the abnormal winter monsoon prevented the water vapor fr om the ocean reaching the land. The formation mechanism of such anomalous atmosp heric circulation which lasted three months stably over Eurasia Continent is yet to be further studied.