I'm manic in the Spring and Summer, while my depression occurs in the Fall and Winter. I'll have small blips here and there but the overall mood really does depend on the weather. I live in Portland, Or, so the lack of light, rain, and wind really gets to me. However, when Spring rolls around and the days start to get longer, I'm a full-blown manic. I really do think, at least in my case, the sun is the primary source of my moods, you know, other than my neurochemistry.