Private Pilot Private Exam

A stable air mass is most likely to have which characteristic?

1. Good surface visibility

2. Poor surface visibility

3. High turbulence

4. Frequent thunderstorms

The correct answer is: Poor surface visibility

A stable air mass is typically associated with good surface visibility, which is a key characteristic of stable atmospheric conditions. When an air mass is stable, it tends to resist vertical movement, leading to a uniform distribution of temperature and moisture. This stability often results in a well-defined `lid` on convective currents, allowing for clearer air and better visibility. Stability also leads to fewer clouds and less atmospheric disturbance, which helps maintain good visual conditions. In contrast, poor visibility would usually be linked to instability in the air mass, such as increased moisture and cloud formation, which often occurs in an unstable atmosphere. The presence of high turbulence and frequent thunderstorms is also indicative of unstable air masses, as they promote vertical movement and convective activity, leading to chaotic weather patterns. Therefore, the characteristic of a stable air mass aligns most closely with good surface visibility.