Term

clear air turbulence

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

Turbulence encountered in cloud-free air, typically near jet streams and at high altitudes — invisible to radar and difficult to forecast precisely.

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Quick Facts

Type
Weather Hazard
Definition
Turbulence encountered in cloud-free air, typically near jet streams and at h...
Used By
Pilots, Dispatchers

Definition#

Clear air turbulence (CAT) is turbulence that occurs in cloud-free conditions, typically at high altitudes near the jet stream, mountain waves, or sharp temperature gradients. It is not visible on weather radar.

Why It Matters Operationally#

CAT is the leading cause of in-flight turbulence injuries because it occurs without visual warning. PIREPs are the primary source of real-time CAT information.

See Also

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