What is the risk of sailing in fog?

Sailing in fog presents a significant risk primarily due to reduced visibility. When visibility is compromised, it becomes challenging for sailors to accurately see other vessels, navigational aids, or coastlines, increasing the likelihood of collisions or running aground. This diminished ability to visually navigate places greater importance on relying on instruments, sound signals, and radar, which may not always be available or effective. Thus, the core danger of sailing in fog is indeed the obscured sightlines that can lead to serious incidents on the water, making it critical for sailors to be aware of these conditions and take necessary precautions.