Low-level wind shear, which results in a sudden change of wind direction, may occur under which condition?

Low-level wind shear occurs when there is a rapid change in wind speed or direction over a short vertical distance. The correct choice, which identifies a situation conducive to this phenomenon, describes a low-level temperature inversion combined with strong winds aloft.

During a temperature inversion, where warmer air sits above cooler air at the surface, a stable layer can form. Strong winds above this inversion may not mix downward effectively, leading to a significant difference in wind speed and direction just below the inversion layer. When an aircraft descends or climbs through this layer, it can experience a sudden shift in wind, creating wind shear that can be hazardous during takeoff and landing.

While high air pressure can influence wind patterns, it does not inherently create shear. Wind shear is also not exclusively tied to thunderstorms; it can occur in various weather conditions, including stable ones, where the situation may not enable turbulent mixing. Thus, the combination of a low-level temperature inversion and strong upper winds is a key contributor to the occurrence of low-level wind shear, explaining why this condition is the correct answer.