So, I just want to start out by saying that I really really admire the level of depth that the World of Gotha people go to with their mapmaking. And I'm now really wanting to be able to do this with my maps (hopefully without the use of fractal terrains cause I'm not terribly happy with any of those landshapes). What I'm wanting to do is imitate the style for the rainfall and also the level of detail with the climates on these maps in particular...

Climate
Rainfall
Temperature

I have photoshop as well, so if I could use that to do this, that would be even better. I'm just not 100% sure on how I would go about this.