Which of the following statements best describes steam fog?

Steam fog is primarily formed when cool air moves over warmer water, causing moisture in the air to evaporate and saturate the cooler air. This process results in the formation of tiny water droplets that cluster together, creating a fog. When the air reaches saturation point and cannot hold any more moisture, visible water droplets appear as fog, which is often seen over bodies of water or during certain weather conditions.

While some of the other statements may have elements of truth, they do not encapsulate the defining feature of steam fog. For instance, while steam fog can certainly occur in specific weather conditions, it does not necessarily indicate clear and cold weather. Additionally, although steam fog can appear as a low-lying cloud, its defining characteristic is the saturation of air due to the evaporation of water. Finally, steam fog does not inherently lead to precipitation, as it consists of suspended water droplets in the air rather than a sign of impending rain or snow. Therefore, the focus on air saturation accurately captures the essence of steam fog formation.