C_M = 9

(a) TECHNICAL SPECIFICATION

Altocumulus of a chaotic sky, generally at several levels.

(b) EXPLANATION

(i) The main characteristic of this sky is its chaotic, heavy and stagnant appearance. The clouds of the middle level consist of superposed, more or less broken cloud sheets of ill-defined species or varieties, with all transitional forms from a rather low and opaque Altocumulus to a high, translucent and fibrous veil of Altostratus.

(ii) This sky also generally exhibits a diversity of clouds belonging to the low and high levels.