Cumulonimbus cloud over western Africa near the Senegal-Mali border. Cumulonimbus clouds rise vertically until they hit a natural barrier, known as the tropopause, and then flatten out. Cumulonimbus clouds usually herald the onset of a severe storm.
Twin lenticular clouds formed over peaks in the Omataco Mountains near Otjiwarongo, Namibia in Africa. Although lenticular clouds have been seen before, it’s strange to see them form at the same time, side-by-side.