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Rainfall and reference crop evapotranspiration are analysed for Njemps Flats, a semi-arid area in Baringo District, Kenya. Examining the monthly rainfall totals, there is no significant difference in rainfall amount between two stations 17 kin apart but daily rainfall totals tend to become independent. Rain-feed agriculture is very risky. Rainfall inclusion in irrigation scheduling causes difficulties. Annual and monthly rainfall was homogenous between 1965 and 2000. The primary reason for the worst droughts in the area is the failure of April-May rainfall. Examining annual rainfall, the lightest rainfall events have become more frequent. The heaviest rainfall events are infrequent but they make up a significant percentage of the total rainfall. Annually, the number of rain-days has decreased with time but rainfall shows no similar decrease, inferring that the rainfall amount per rain-day is increasing. Rainfall amount for the months of May and November has decreased with time while rainfall amounts per rain-day for the months of April, July and August are increasing. Land and water management schemes in the area must be designed to cope with drought periods as part of supply characteristic of the area. (C) 2002 Elsevier Science Ltd.