Well, the months after October are COLD. Don't get me wrong, the overall temperature is much warmer than back home in upstate New York. You shouldn't see much snow here. However, the houses here don't have handy things like... oh, insulation or proper heating. There's nothing like sitting at your computer and noticing your own breath. Brr.
Luckily, I have a nice hot shower that I can pop into before bed. I also have a wonderful kotatsu. (If you're wondering, it's a table with a heating element underneath and a heavy blanket that sits above that, but below the actual table top. The blanket keeps in all of the warmth, and your toes will love you.)
Outside of the home, (actually, this also applies to inside my house too...) dressing in layers is key to survival. As I write this I'm wearing an undershirt, long sleeved button-up blouse and a hoodie. I'm I the warmest room in the whole middle school... and I'm still cold. If I had blazers, I'd wear 'em to work.
The poor students here get to sit in really cold classrooms. At the elementary school most of the children dress in many layers and wear their winter jackets around. At the middle school though, they have to wear uniforms. The uniforms allow for a bunch of layers underneath, and I've seen some girls with winter coats on top, but the girls are still stuck in skirts. I think they should have the option of pants, at least in the winter. Have some mercy, Japan!
Many of the kids also carry around little warm pouches. You just squeeze the pouch, and it warms up. They don't seem to last the whole day through, but it's always fun grabbing them off of the students' desks and kidnapping them for a bit.
It was a little bit of a bummer when it was getting dark right after I got out of work (at 5 p.m.) and I was unable to muster the desire to crawl out from under my kotatsu. Luckily, it's getting nice and sunny again, and I'm sure the warmth is on its way. (And a few weeks after it arrives, it'll get muggy and try to kill me dead. ;_; )