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Estimation of the spatial and temporal characteristics of key water balance components in data scarce regions is a large challenge worldwide. This paper presents the derivation of the 30-year surface water balance components (rainfall, temperature, potential and actual evapotranspiration ( ET p and ET a ) runoff). Monthly rainfall and mean temperature from 28 synoptic stations in Malawi during 1971–2000, together with soil moisture capacity extracted from the International Geosphere-Biosphere Programme Data Information Services (IGBP-DIS) Global Gridded Surfaces of Selected Soil Characteristics database at 0.5° × 0.5° grid resolution were used as model input. Ordinary Kriging was applied to examine the spatial distribution of the components using a 0.5° × 0.5° grid resolution. Temporal trends were investigated using the Mann–Kendall test at α = 0.05 significance level. The results showed: (1) an area of high rainfall, ET a and runoff areas located in the south east and north east highlands and decreasing westwards. Temperature and ET p were highest in the lower Shire River valley and along Lake Malawi; (2) Mann–Kendall trends suggested statistically significant positive trends in mean annual temperature and ET p and declines in annual rainfall, ET a and runoff, though their trends were not statistically significant. The contrasting trends ET p and ET a are a manifestation of the complementary relationship. The decline in rainfall coupled with temperature increase suggests that Malawi became more water-limited during 1971–2000. [ABSTRACT FROM AUTHOR]