The diagram illustrates the various natural processes and mechanisms that lead to the formation of rain-shadow deserts.
Overall, winds travelling towards the coast are forced to travel upwards at the windward side of the mountain, with the moist air rising and transforming into clouds. Rainfall occurs on the same side of the mountain before the remaining dry air moves over and down the other side of the mountain, eventually arriving at the inland areas.
Initially, winds originating from the sea approach the coast, where they are given no choice but to rise once reaching the windward side of said mountains. Air heavily concentrated with water also moves upwards and subsequently cools down, forming clouds which eventually release the held water as rain at the windward side of the mountains.
Then, on the other side of the mountains (known as the leeward side), dry air arriving from the windward side has already travelled over the top of the mountain and begins to descend down this side of the mountain. This dry air is at some point converted into dry winds, which reach inland areas after completing their path over the mountains. These inland areas are thousands of kilometres away from the coasts and are where the rain-shadow desert is formed.