Of all the clouds in the sky, the lenticular cloud is one of my favorites. This is the cloud that is shaped like a lens. Some even have what's called a "flying saucer" shape. These clouds are usually found at the crest of a wind wave found around mountains. As the wind moves up one side of the mountain, the wind crests at the top and moves down. One of the neat things about this cloud is, since the wind and water vapor are moving, the cloud retains its shape.