ΔE 19.1, loose: different enough that you should pick on purpose. Pale Sand is a little darker, much more saturated than Cloudy Sky.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Pale Sand is a little darker, much more saturated than Cloudy Sky.
The same difference applies the other way round: Cloudy Sky is a little lighter, much more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Cloudy Sky on the colour wheel See Pale Sand on the colour wheel
All matches: Cloudy Sky equivalents · Pale Sand equivalents