Private Pilot Private Exam

What weather change is guaranteed when flying across a front?

1. Change in visibility

2. Change in altitude

3. Change in wind direction

4. Change in air pressure

The correct answer is: Change in wind direction

When flying across a front, a change in wind direction is a consistent and expected phenomenon. Weather fronts typically represent a boundary between two different air masses, which often have distinct temperature, humidity, and pressure characteristics. As an aircraft crosses from one side of the front to the other, it will encounter very different wind patterns. For example, ahead of a cold front, winds may be coming from a certain direction, typically from the south or southwest, while behind the front, winds generally shift to come from the north or northwest. This change in wind direction is a direct result of the contrasting air masses's properties and how they interact at the front. It’s important to note that while other weather changes can occur as well, such as variations in visibility and air pressure, these are not guaranteed across every front. Visibility may fluctuate due to precipitation or fog that can be present at a front, but it is variable. Similarly, while air pressure does change across fronts, the precise change will depend on specific conditions and is not a guaranteed indicator. Thus, the reliable and consistent aspect of weather change when navigating across a front is the shift in wind direction.