Clouds of the Day - Castles in the Sky - Monday, October 23, 2023

Altocumulus include some of the most interesting cloud formations. The photos below show the sequence of cloud formations from the late morning until early evening. The first seven photos show examples of Altocumulus castellanus and Altocumulus floccus. They form in a layer of conditionally unstable air in the middle levels between 6,500 ft to 20,000 feet (2,000 m to 6,000 m). Air is conditionally unstable when a lifting mechanism, such as rising motion due to an approaching front or lift caused by an approaching or leaving jet stream aloft. The lift causes the to rise until it becomes unstable and condensation occurs.

With a little imagination, castellanus look like the turrets found on castles, hence the reference to Castles in the Sky - Altocumulus castellanus.

The clouds below mostly various forms of cumulus. These also form when a lifting mechanism, such as a front, heating, or moisture moves into the area.

Altocumulus, Cumulus, (center to upper left) and cumulus congestus (middle right lit by the Sun)

Cumulus, cumulus congestus

Cumulus in rows

Cumulus in rows

Altocumulus floccus (shaped like flocks of wool).