Based on the daily precipitation datasets from 1967 to 2008 recorded at stations over the Tibetan Plateau, the precipitation concentration degree (PCD) and precipitation concentration period (PCP) of the Plateau are defined. By means of EOF and correlation, as well as spatial and temporal distributions of PCD and PCP, the relationship between PCD and plateau heavy rainfall, and signals of PCP are investigated. The results show that PCD of the plateau area is between 0.4 and 0.8, while PCP is within 36-41 pentads. In space scale, PCD is nearly congruous in the whole region, while PCP manifests a north-south reverse pattern mainly. In time scale, PCD appears to be a subdued tendency when PCP displays an advanced characteristic. Except for a few places in the southern plateau, PCD shows positive correlation with days as well as amounts of intensive rainfall on plateau. In addition, the water vapor transports have significant differences between northern and southern PCP of the plateau, the onset of Bay of Bengal monsoons may have an effect on PCP of the southern plateau.
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