Cool Summer is the purest cool season in the summer family, scoring the maximum -1.00 on temperature. Skin has a clear pink or blue cast, hair runs ash brown to soft dark, and eyes are typically blue, grey or cool green.
It shares its perfect coolness with Cool Winter. The separator is chroma: -0.60 here, meaning softened, against 0.70 there, meaning clear. Both are unambiguously cool; only one is bright, and mixing them up is why some people find cool colours either perfect or harsh with nothing in between.
