A wind shift occurs when sustained wind speeds are what or more?

A wind shift is defined as a significant change in the direction of the wind that is typically associated with a change in weather conditions. In meteorological terms, a sustained wind speed of 10 knots or more is generally considered sufficient to indicate a wind shift. At this threshold, the change in wind direction is more likely to reflect a substantial atmospheric change, such as the passing of a front or the development of a weather system.

This understanding helps pilots and meteorologists assess changes in weather patterns and make informed decisions about flight conditions. While it might be true that smaller wind shifts can occur at lower speeds, the 10-knot threshold specifically highlights when such shifts are more relevant and significant for aviation safety.