That is true, I am not sure if Destiny Island (or at least the one that we've seen, and even the other island that was in KH2 (which looks totally like it has Twilight Town on it.)) chain would cause that much of a

I think there was a mountain on the main island, though, and if wind comes from the direction of the mountains then the mountain serves as a massive weather vane and would clear out the skies below it for miles in a massive delta pattern.

...Never knew my self-taught geography would come in this handy!