How does the Season system work? (Not the same)

Question

In 5th gen, there are a lot of new things but i don't get Season system in Pokemon B&W.
Such as, do some pokemon just appear in Winter and not in Summer or something like that? or when in Summer does pokemon level up easier than in Autumn?
Please help, Thanks :)

Answer 1

You can search here to find out about [weather][2]. And pokemon dont level up easier in any month. If you go to serebii and search e.x.torchic, at its stats you can see its experiance growth. Each pokemon has different(for example, torchic has medium slow. Wurmple has medium fast. So wurple will level up faster than torchic).
[2]: http://pokemondb.net/black-white/seasons