Wavelength indication

[lolly2]

If even the wave heights were elaborated with colors like that of the wind, it would be instantly readable just as it is for the wind

I'm a sailor

[Gkikas LGPZ]

The wave heights are "colored" (from blue to magenta)
https://www.windy.com/?waves,44.402,-13.711,5,m:ePbafMO,a:FFMFF

Also, you can change the colors, using:
"menu" - "settings" - "advanced settings" - "modify layers colors"