At what altitudes does clear air turbulence typically occur?

Clear air turbulence (CAT) is primarily associated with the jet stream, which is found at higher altitudes in the atmosphere, specifically between 20,000 and 40,000 feet. This phenomenon occurs in clear air, away from thunderstorms, and is typically caused by wind shear—where there is a significant difference in wind speed or direction over a short vertical distance.

Understanding that most commercial flights operate within this altitude range helps underscore why CAT is often encountered during these phases of flight. Pilots and meteorologists study jet streams and the atmospheric conditions at these altitudes to predict and manage the risk of turbulence, making the knowledge of this correct altitude range critical for flight safety and passenger comfort. Consequently, the altitudes below 10,000 feet and above 40,000 feet are not associated with the common occurrences of CAT.