Well Ive often wondered about this too. I love it when I go to the stand and it rains the next day. I think it washes everything out of the area and makes it fresh again. They say a whitetail has trouble smelling in the rain. Just make sure your scent free and hope that the rain does clean the area. The smell of the fresh rain itself could throw the deers senses off. Now I think if your in the woods hunting and it starts raining I think that your scent could be trapped into the water molecules and if a deer so happened to come by ya, he might smell ya. who knows, if I start thinking about all of this it will just make me even more scent cautious I dont think I can be anymore scent free.