What have been the temperatures there lately? Extreme heat does it as mentioned but you said its been cold there so never know. My personal opinion is any kinda of wax or whatever could damage a tire, just some may take longer than others. If you're using it to keep your tires shiny, just buy some Black Magic Tire Shine spray or whatever. Might work better and could solve the problem. Whatever it is, hope ya find it out. Good luck!