Mind-Blowing Cloud Formations You Probably Haven't Seen Before

Lenticular clouds are shaped like lenses or almonds or...flying saucers! They may get their shape from hilly terrain or just the way the air is rising over flat terrain. These strange, unnatural looking clouds sometimes form downwind of hills or mountains. They are quite unusual in the British Isles but do occasionally occur. They look a lot like the traditional shape of flying saucers in science fiction, and real lenticular clouds are believed to be one of the most common explanations for UFO sightings across the world. When air blows across a mountain range, in certain circumstances, it can set up a train of large standing waves in the air downstream, rather like ripples forming in a river when water flows over an obstruction. If there is enough moisture in the air, the rising motion of the wave will cause water vapour to condense, forming the unique appearance of lenticular clouds.