Clouds Formation

Family D1 includes:
- Genus Cumulus (Cu): Clouds of free convection with clear-cut flat bases and domed tops. Towering cumulus (cumulus congestus) are usually classified as family D2 clouds of considerable vertical development.
+ Species Cumulus fractus (Cu fra): Cumulus clouds broken up into ragged and changing fragments.
+ Species Cumulus humilis (Cu hum): Small cumulus clouds usually with just a light grey shading underneath.