Soft Summer scores -1.00 on both contrast and chroma, the lowest available on either. Colouring is blended: hair, skin and eyes sit close together in depth with no single feature standing out sharply. Eyes are often a mixed grey-green or grey-blue that changes with what is worn near them.
Temperature is only gently cool at -0.35, which makes softness rather than coolness the defining quality. This is the mirror of Soft Autumn, which is equally muted but gently warm. The two are the closest pair among the twelve.
How to check whether this is your season
Test softness before anything else. Hold a clear bright colour next to your face, then a greyed version of the same hue. If the bright one seems to sit in front of the face rather than with it, you are in a soft season.
Assess contrast. If someone would struggle to say whether your hair is much darker than your skin, contrast is low and this season is in range.
Then temperature, gently. At -0.35 the cool lean is mild. Compare a soft mauve with a soft camel; Soft Summer prefers the mauve but not dramatically.