C_L = 6

(a) TECHNICAL SPECIFICATION

Stratus nebulosus or Stratus fractus of dry weather, or both.

(b) EXPLANATION

(i) Stratus nebulosus generally consist of a continuous single sheet or layer with a fairly uniform base, usually grey but occasionally dark or menacing.

(ii) Stratus fractus are a transitory stage during the formation or the dissipation of a layer of Stratus.

(iii) Differences between this Stratus fractus and Stratus fractus of wet weather are pointed out in the explanation on C_L = 7.

(iv) When Stratus fractus occur beneath a layer of Stratus nebulosus, they may be either fragments that become merged with the base of the layer when the latter is in the process of thickening, or fragments detached from the base when the layer is in the process of breaking up.