Hiliary

I have had these white patches/spots on my upper arms for over a year or so now. I have gone Tanning before but the last time i did was almost a year ago and the spots have no gone away. They are not ichy or scaly but they are about the size of a quarter or more and on both arms. They started to appear somtime last spring after i was tanning for a while and realy showed once summer came. This past winter there has been red dry patches around them and i have used lotion to clear that up and it helped the dry red patches (I do live in a northern state with cold winters) but my white spots are still there. I have tried to look up everything i can and can not find anything with simulare symptoms as mine.. Can anyone help me? I would like to start tanning again to give myself some color but i don't want to risk making my spots worse!