Fog and low clouds (FLC) are a typical feature along the southwestern African coast, especially in the central Namib, where fog constitutes a valuable resource of water for many ecosystems. In this study, a novel algorithm to detect FLC over land from geostationary satellite data using only infrared observations is presented. The algorithm is the first of its kind as it is stationary in time and thus able to reveal a detailed view into the diurnal and spatial patterns of FLC in the Namib region. A validation against net radiation measurements from a station network in the central Namib reveals a high overall accuracy with a probability of detection of 94 %, a false alarm rate of 12 % and an overall correctness of classification of 97 %. The average timing and persistence of FLC seem to depend on the distance to the coast, suggesting that the region is dominated by advection-driven FLC. While the algorithm is applied to study Namib-region fog and low clouds, it is designed to be transferable to other regions and can be used to retrieve long-term data sets.