Final answer:
Atmospheric stability class F refers to overcast skies, whether night or day. It signifies a stable atmosphere with poor air quality and stagnant weather conditions.
Step-by-step explanation:
The atmospheric stability class F refers to overcast skies, whether night or day.
Atmospheric stability is a measure of the vertical movement of air in the atmosphere. It determines how air pollutants disperse and how weather conditions develop.
In class F, the atmosphere is considered stable, meaning that air near the ground tends to remain in place and does not mix or disperse effectively. This can lead to poor air quality and stagnant weather conditions.