Agricultural drought is common occurrence in most semi-arid places including Eastern Free State and this hazard has detrimental effects on crop production. In the study 12 weather stations in the region were selected based on the length of record of the climate data (> 20 years). The Water Requirement Satisfaction Index (WRSI) was utilized to quantify the drought in this study. The index was determined for different crop growing periods of a 120-day maize crop per agricultural season. Median values were then mapped to assess the evolution of drought according to different planting period. In most parts of the Eastern Free State, WRSI values in most of the growing periods ranged from 61 to 80. These indicate maize crop was subjected to mild drought conditions over the growing periods. The results also show low temporal and spatial variability.
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