What minimum criteria indicate a wind shift must be reported?

A wind shift involves a significant change in wind direction, which is crucial for aviation safety and operation. A change of 45 degrees or more is considered significant enough to warrant a report because it can affect flight performance, navigation, and aircraft handling characteristics. Meteorologically, a shift of this magnitude may indicate the passage of a weather front or significant atmospheric changes, which could impact flying conditions.

While smaller changes in wind direction can occur frequently and may not have a substantial impact on flight operations, a 45-degree shift is a clear indicator that crews and air traffic control should be aware of potential changes in weather patterns. The importance of sharing this information lies in its relevance to maintaining safe aviation practices, especially during takeoff and landing phases.