FAA Ground School Practice Test

What is a common result of atmospheric stability?

1. Heat waves

2. Sustained low cloud cover

3. Thunderstorm development

4. High winds and turbulence

The correct answer is: Sustained low cloud cover

Atmospheric stability refers to the tendency of air parcels to remain in their original position rather than rise or sink, which can greatly influence weather conditions. A common result of stable atmospheric conditions is sustained low cloud cover. This occurs when cool, moist air is trapped under a layer of warmer air, preventing vertical movement. As a result, clouds may form close to the ground and persist for extended periods, leading to overcast conditions. In contrast, unstable air often leads to significant vertical development and can give rise to phenomena such as thunderstorms. When the atmosphere is unstable, rising air can lead to the rapid development of cumulus clouds into larger storm systems. Additionally, high winds and turbulence are typically associated with unstable air, where vertical movements can lead to gusty conditions. Heat waves, characterized by prolonged periods of excessively hot weather, may occur during stable conditions but are not a direct consequence of atmospheric stability in the same way that sustained low cloud cover is, making low cloud cover the most relevant result in this context.