FAA Aircraft Dispatcher (ADX)MeteorologyMedium
A dispatcher receives a pilot report describing steady light rain, stratus cloud layers, and a smooth ride with restricted visibility due to haze. This report is most indicative of what type of air mass?
- AConditionally unstable air
- BStable air
- CUnstable air
- DNeutral stability air with high turbulence
Show answer & explanationAnswer & explanation
Correct answer: B. Stable air
Stable air is characterized by stratiform clouds, steady/continuous precipitation, smooth flying conditions, and restricted visibility due to haze, smoke, or fog because pollutants and moisture are not mixed vertically. Unstable air instead produces cumuliform clouds, showery precipitation, and turbulence.
Why the other options are wrong
- A. Conditionally unstable air would still show cumuliform development once lifted, inconsistent with a smooth stratus report.
- C. Unstable air produces cumulus clouds, showery precipitation, and turbulence, not smooth stratus conditions.
- D. This combines contradictory terms; stable air is associated with smooth conditions, not turbulence.
Atmospheric Stability Indicators
Stable air produces stratiform clouds, steady precipitation, smooth air, and poor surface visibility (haze/fog); unstable air produces cumuliform clouds, showery precipitation, turbulence, and good visibility.
- Stable air: stratus clouds, continuous precipitation, smooth ride
- Unstable air: cumulus clouds, showery precipitation, turbulent ride
- Visibility is often poor in stable air due to trapped haze/smoke/fog
Memory trick: 'Stable is Smooth and Stratus; Unstable is Uneven and cUmulus.'