You can melt it and mix in some dyes… but… the darker wax will tend to melt much more easily in the sun, so you’ll have to add paraffin wax as well.
You might also consider giving the deck a light, temporary spray of some paint, like a latex house paint, that’ll buff off easily when you get back. A light gray or beige - something like that works well for boat decks in the tropics, no reason it shouldn’t work for you.