Fog

(Section 2.5.3.1)

Fog is composed of very small water droplets (and sometimes minute ice particles) in suspension in the atmosphere, reducing the horizontal visibility at the Earth’s surface to less than 1 000 m. The vertical extent of fog ranges from a few metres to several hundred metres.

Within the fog. Flying within fog, the airborne observer has low visibility. Icing, when it occurs, is generally very light. In the case of relatively shallow fog, turbulence is absent or light, while in deeper fog, turbulence may be light to moderate.

Above the fog. Viewed from above, fog appears similar to a smooth layer of Stratus. It may be flat, slightly undulated or display rounded domes of various size.