Clear air turbulence typically occurs at what altitudes?

Clear air turbulence (CAT) is primarily found at altitudes between 20,000 and 50,000 feet. This turbulence is typically encountered in the upper levels of the atmosphere, often associated with jet streams and certain weather patterns that can create sudden changes in wind speed and direction.

The higher altitudes are significant because this is where the wind patterns can be particularly strong and variable, especially in relation to the jet stream, which flows at these heights. As aircraft ascend to cruising altitudes in this range, they may inadvertently pass through regions where CAT is active, resulting in unexpected turbulence.

Lower altitudes, such as those below 20,000 feet, tend to be more influenced by surface weather systems and ground-based phenomena, which typically do not generate clear air turbulence. So, the most reliable occurrence of CAT is indeed within the range of 20,000 to 50,000 feet, making this the correct selection for altitude associated with clear air turbulence.