Yuki hated the snow. It was only one of the many subtle ironies about his character that would baffle the many people who believed they knew him, but in reality had never delved past his well-sanded exterior. He honestly didn't mind the cold, or the inconvenience of ice and slush on roadways, or any of the other little annoyances most people had about snow. What he detested of winter was it's silence- it's absolute sterility. When snow fell on the ground, people shut themselves in their houses, the animals sought shelter, even the air seemed to be a bubble that trapped sounds into smaller territories; the sound of boots crunchingwas even muffled until it drew dangerously close. The silence allowed for the unknown to exist, for sudden motion to overtake him with shock, which is why he prefered the summer, because amidst the noise, and the birds chirping and the incessant hum of cicadas, there are no surprises.
He hates the snow, because it has a facade of purity, when it is merely white. It's blinding brightness is only an inversion of pitch black. Yuki has a rooted fear of the dark, but the deceptive brightness scares him the most.
Maybe it isn't really an irony though; He hates the snow in just the same manner as he hates himself.