Guide
The score works best as a quick summary of multiple ocean signals at once. A 7/10 does not just mean "decent." It usually means several conditions are lining up reasonably well, while a few factors still keep the water from being truly calm or clear.
Guide
Tide does not just change water height. On shallow reefs, very low tide can make entry harder, reduce room over coral, and make some areas feel less comfortable even if the surface looks fairly calm. A large daily tide swing can also make conditions feel less consistent.
Guide
Many people check only wave height, but snorkeling quality depends heavily on what kind of energy is in the water. Wind chop can make the surface messy even when swell is moderate. Cloud cover and rain can also reduce visibility value even when the ocean is physically manageable.