Decentralized electricity systems based on variable renewable energy (VRE) sources such as wind power can provide affordable, dependable, and modern energy in a manner consistent with the Paris Agreement. Such sources are, however, sensitive to extreme values of climatic factors—an issue that may jeopardize power system reliability. As a resource-rich region with a high proportion of rural population without access to electricity, Africa has been of wide interest in studies on VRE-based electricity generation. Nevertheless, there is still a major gap in our continent-scale understanding of the wind power potential and its variability at different time scales, as well as the influence of low-wind-resource periods in Africa. Using ERA5 hourly estimates of wind speed, the present study investigated the adequacy and temporal variability of local wind power potential across Africa over the 2000–2017 period. The results indicated that design requirements of wind power systems are, on average, fulfilled in regions in the North, South, and Horn of Africa at different time scales. However, low-resource periods were shown to have a significant impact on the reliability of wind power potential in the majority of the continent. Demand flexibility can reduce the severity of these periods and help to achieve design requirements.