What does a wind shear warning indicate to pilots?

A wind shear warning indicates to pilots that there are potential variations in wind speed and direction. Wind shear is a change in wind velocity (speed and/or direction) over a short distance, which can be particularly dangerous during takeoffs and landings. Such variations can lead to sudden changes in an aircraft's performance; for instance, an increase in headwind can affect lift, while a downdraft can lead to unexpected altitude loss.

Understanding wind shear is crucial for pilots, as it helps them anticipate and respond to changes in flying conditions that may affect aircraft control and safety. This warning serves as a critical alert for pilots to be prepared for these potentially hazardous conditions, allowing them to adjust their flying techniques accordingly to maintain safety during flight operations.

The other choices do not accurately reflect the significance of a wind shear warning. Steady winds, improved visibility, or the presence of cloud barriers do not encompass the critical information conveyed by a wind shear warning, which specifically highlights the dangers associated with fluctuating winds.