Nothing strange about it IMHO.
Okta(s): the international unit for reporting cloud amount. Cloud amount is assessed in total which is the estimated total apparent area of the sky covered with cloud.
1 okta is one-eighth of sky covered with cloud. 0 okta = sky clear, 1-2 oktas = few, 3-4 oktas = scattered, 5-7 oktas = broken and 8 oktas = overcast.