The Yamuna catchment up to Kalanur is studied. The representative character of limited pluviograph data was determined using the storm index concept. After establishing a relationship between the limited pluviograph data and areal rainfall data, the possible effects of areal rainfall variation on the use of limited data was studied. A simulated temporal rainfall pattern for the area was then worked out and applied in the unit graph analysis, which led to the development of interesting relationships between rainfall intensity, Antecedent Precipitation Index and Phi-Index on the one hand and the API-IL relationships on the other. These two put together have given rise to a reasonable peak trend prediction diagram for the Yamuna catchment up to Kalanur.