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Evidence is presented to show that the annual mean cloud optical depth in the leeside of the Tibetan Plateau exhibits a global maximum between 60oS and 60oN. This large cloud optical depth is due to the persistence of deep stratus clouds (primarily the nimbostratus and altostratus) during winter and spring. These deep stratus clouds are generated and maintained by the frictional and blocking effects of the Tibetan Plateau. The plateau slows down the over-flow, inducing downstream mid-level divergence; meanwhile it forces the low-level surrounding-flows to converge downstream, generating sustained large scale lifting and stable stratification that maintains the thick stratus clouds. This stratus clouds produce extremely strong cloud radiative forcing at the top of the atmosphere, which fundamentally influences the local energy balance and climate change. Analysis of the long-term meteorological station observation reveals that the monthly mean anomalous cloudiness and surface temperature vary in tendon. In addition, the surface warming leads to destabilization and desaturation in the boundary layer. These evidences suggest positive feedbacks between the continental stratus clouds and surface temperature through changing lower-tropospheric relative humidity and stratification. It is shown that the positive feedback mechanism is more robust during the period of the surface cooling than during the period of surface warming. It is suggested that the positive climate feedback of the continental stratus cloud may be instrumental in understanding the long-term climatic trend and variation over the East Asia. 1 1