1. Altocumulus, altostratus and nimbostratus are medium-level clouds--between 2,500 and 5,500 metres

2. In most cases, when the disturbance in the weather is weakening, nimbostratus clouds rise and alters into Altostratus.

3. It is lighter in color than nimbostratus and darker than high cirrostratus.The sun can be seen through thin Altostratus…

4. Altostratus A cloud of a class characterized by a generally uniform gray sheet or layer, lighter in color than nimbostratus and darker than cirrostratus

5. Altostratus definition, a cloud of a class characterized by a generally uniform gray sheet or layer, lighter in color than nimbostratus and darker than cirrostratus: of medium altitude, about 8000–20,000 feet (2450–6100 meters).