I have Seasonal Affective Disorder.
(Advertisers call it SAD for short, because they love tongue-in-cheek acronymns.)
This means that based on the amount of sunlight my body "experiences," my mood can elevate (or drop) dramatically. When my body receives very little sunlight, say during a five day span of cold rain and overcast skies in November living in a city "nestled" in the hills of a mountain range in Tennessee, I don't get cranky.
I lose my fucking mind. It's really a fabulous combination of unbridled depression and manic, short-tempered anger. Those two fun-filled emotions don't completely blend, but show their colors at random points of the day.

Lord knows he's just fightin' them Nashville blues - Your average Cory Morrow fan.
Think of a chocolate-vanilla swirl ice cream cone. Mmmm. Both flavors of madness.