I'm trying to make climate zones for a word where there are two huge continents as well as one smaller one and a few scattered island chains. Since my continents are so big I'm trying to figure out how far a rain shadow from mountains would extend. How far away do you have to be from a mountain range before you can realistically expect other weather factors to increase the rainfall again?

I hope I dont sound rambling, working the night shift has kind of fried my brain so I'm not as coherent as I'd like to be at the moment.