Water

Why is it the hotter it gets the less likely I am to drink anything but water?

All year long I drink a lot of water but from mid fall till it starts to heat up sometime in the spring I drink a variety of beverages. My favorites are milk and juice. Although I am not much of a soda drinker, I do drink diet soda as well. I also enjoy an occasional smoothie. But once the heat goes up my consumption of water goes up as well. I hardly drink milk in the hotter months. Most of the time juices seem too sweet and never settles as well in the hotter months. Puzzling.

Is it better to drink the variety or is it better to drink more water than other beverages?