What term is used to describe a layer of fog that covers less than two-eighths of the sky?

The term that describes a layer of fog covering less than two-eighths of the sky is "SCT," which stands for "scattered." This meteorological term indicates that the coverage of clouds or fog is between one-eighth and four-eighths of the sky. When fog or low clouds are classified as scattered, it means that the fog is not widespread, allowing for visibility in some areas with breaks in the fog.

In this context, "BR" refers to mist, which does not specifically correlate to the coverage of fog as described. "N/fog" suggests a notation that is more qualitative but does not provide a specific coverage term. "CLR" refers to clear skies with no significant weather, which does not apply to fog conditions. Therefore, "SCT" correctly captures the idea of limited coverage, making it the appropriate term for fog that is not pervasive across the sky.