According to NOAA, altocumulus clouds can resemble fish scales or butter milk if there is enough of them lined up in a row. This is what’s called a Mackerel Sky. Altocumulus clouds can form in rows or patches. Depending on the temperature, altocumulus clouds can be made up of water droplets or ice crystals.
Alto refers to the middle of the atmosphere and cumulus refers to the puffy shape of the cloud or a “heap”. They can form amongst a variety of other clouds too. A couple…..