Under what conditions might low-level wind shear occur?

Low-level wind shear is a significant meteorological phenomenon that occurs when there is a notable difference in wind speed or direction at low altitudes. This condition is particularly likely to happen during a low-level temperature inversion with stronger winds aloft.

In a temperature inversion, the air close to the ground is cooler than the air above it. This situation creates a stable atmospheric layer that can trap turbulence and allow stronger winds aloft to flow above the cooler air without mixing effectively. When an aircraft attempts to ascend or descend through this layer, it can experience abrupt changes in wind direction or speed, leading to wind shear.

This phenomenon is critical for pilots to understand since it poses risks during takeoff and landing, times when aircraft are operating at lower altitudes and are therefore more susceptible to sudden changes in wind conditions. The presence of strong winds above a stable layer coupled with lighter and relatively calm winds at the surface creates an environment where wind shear can occur, thus having significant implications for aviation safety.