How far does a rain shadow extend?

[inspectorjavert]

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.

[Redrobes]

I don't know for sure but I would have thought that once the water has dropped out of the air then its dry and that it will extend until the air passes over water once again to pick up more of it.

My understanding was that air off of the sea is (can be) wet and then it passes over mountains where it is lifted up and the lower air pressure expands it causing the water to drop out then it lowers after the mountains and gets higher pressure again but there is no more water to take up so now it has the capacity to absorb more. So I think its unlikely to rain again until it gets re-saturated or the pressure changes some more.

I believe that trees take up water from the ground and vent it through pours in the leaves. So air can obtain water over trees as well as from lakes and the sea and that is partially why tropical rain forests generate so much rainfall.

[johnvanvliet]

you can use the USA as an example

This is part of the world in April

Screenshot_20211220_221441.png

nearly the whole of the Midwest is a bit dry