Tokyo, Kyoto, Osaka, Hiroshima
At least in Tokyo it says it can get as low as 4 degrees Celsius during that time?
Is 4 degrees Celsius really the end of the world? I'm Canadian so I rarely wear a coat unless it's freezing But if you're from a tropical island, well...pack appropriately! Better you pack warm clothes and not need them than not pack any and need them!
Does anybody know a place to get a duffle bag that is the exact carry on size or close? 22" x 14" x 9"
Try any luggage store -- they usually sell things that are specifically sized for air travel.