Chinook
Chinook
The warm dry winds that blow down the side of the mountain (leeward side) are known as Foehn Winds.
The plural form is valleys.
There are several types of valleys, including V-shaped valleys formed by erosion from rivers, U-shaped valleys carved by glaciers, rift valleys formed by tectonic activity, and hanging valleys created when smaller tributary valleys flow into larger main valleys.
This special dry warm wind is called a Chinook wind. It forms when air descends down the leeward side of a mountain range, such as the Rocky Mountains, causing it to warm and dry as it descends.
Chinook
Hot,dry, little rain. This place usually has lots of sand.
Warm, moist air from the ocean is lifted into the high mountains where it cools and condenses. these " ripe " clouds then drop their precipitation in the valleys on the other side
There are plenty of valleys in Wales.V-shaped valleys are formed by water flow.U-shaped valleys are formed by glaciation.
The likely word is the plural noun "valleys."
The possessive form for the plural noun valleys is valleys'.