system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is Spain so dry compared to Italy? (even Portugal)?

I just went to google maps and just at quick glance the central-east part of Spain is almost a dessert compared to same latitude parts of Italy. Also Portugal seems to be more green (maybe closer to Ocean). 

I've been told that the Sahara winds dry up that region but idk if that's true or why the Sahara winds only dry up that region and not Italy. I've been googling without much luck.
gpt
Spain is one of the most mountainous countries in Europe, the dry areas occur after the prevailing winds, mostly from the west, pass over mountain ranges. The rain falls over the mountains and this exhausts the clouds. In the driest parts of Spain prevailing weather would have to come over the central chain or the Sierra Morena or the Betic chain.