What is the effect of stable air on visibility?

The impact of stable air on visibility is often characterized as fair to poor. When the air is stable, it tends to prevent the vertical mixing that would otherwise help disperse pollutants and moisture in the atmosphere. This stability can lead to the accumulation of haze, smoke, fog, or low clouds, which can significantly reduce visibility.

In stable conditions, temperature inversions frequently occur, where a layer of warm air traps cooler air and associated contaminants near the ground. This can lead to an increase in atmospheric pollutants, which also contributes to reduced visibility. Therefore, while stable air doesn’t guarantee poor visibility, it often results in conditions that lead to fair to poor visibility due to the lack of vertical mixing and the potential for moisture and particulates to persist in the lower atmosphere.

Other options like good visibility would not typically apply here since stable air conditions are often linked to restricted vertical movement and possible haze, resulting in diminished clarity. Showery conditions suggest precipitation, which doesn't directly reflect the characteristics of stable air. Thus, the correct understanding is that stable air typically leads to fair to poor visibility.