If you keep your skin moist during extremely hot weather, it'll prevent heat rash and other skin irritations. When it's hot outside we tend to sweat underneath our skin, which can lead to breakouts. I always keep a mini bottle of this with me.
This self-tanning sunblock mousse is awesome because it gives you a gradual, natural looking glow without that weird self-tanner scent. It has SPF in it, too. I've been putting it on every single morning.