The altocumulus is one of the middle cloud with a height ranging from 2000 to 6000 meters. There are many types of morphology. Sometimes, the middle atmosphere is disturbed, and it is most likely to produce altocumulus clouds. In addition, there are many different types of terrain or some fluctuation may also appear altocumulus. These clouds are flaky, layered, wavy, roller-shaped, etc. The distribution can be neatly arranged sometimes, but it can also be scattered. It is composed of small water droplets and ice crystals. When temperature is below 0℃, it is mainly composed by solid state of water. In addition, the ice crystals fall from the high distributed altocumulus clouds may will form another cloud body similar to cirrus clouds. As for the upper altocumulus cloud, there will be a hollow, which can see through the blue sky. The top of the altocumulus cloud can be bright but the bottom will be gray and dark. Altocumulus clouds can also be accompanied by light rainfall, and rain shaft can also appear if they fall to the ground.