What characterizes advection fog?

Advection fog is characterized by warm, moist air moving horizontally over a cooler surface, leading to the cooling of the air to its dew point. This cooling causes condensation, which manifests as fog. This phenomenon is often observed over bodies of water or when warm air flows over cold land, resulting in reduced visibility. The process relies on the movement of air rather than stillness or turbulence, making it a distinct type of fog compared to others that are influenced by different conditions.

Advection fog typically does not form under clear, calm nights, nor is it generally associated with elevated areas or the rising of warm air. Instead, it is formed through the consistent movement of warm, moist air across cooler surfaces. Understanding this process is crucial for recognizing and anticipating weather conditions that can affect flight operations, such as lower visibility due to fog.