Idk, on the emulator it didn't rain in Spring or Autumn but I thought that was because I changed the date on my computer after hitting my seed. Perhaps there is actually a way to make it not rain in Spring/Autumn on the DS. I'll have to try it when I find the time.
And lol, timer0 trolling.
EDIT: You shouldn't be doing 0, 1, 2 etc advances. It should be 0, 5, 10 or something like that.