Where is the US dry?

Answer 1

There are many areas where the US is dry, but the largest general area is the Western United States, which has overall very low humidity (although of course along the coast there is some).

I grew up in Colorado, and have traveled extensively in the West, and the air is very dry overall. It was hard to travel east to New York when I moved there. I thought the humidity would kill me. It did not, but it kind of felt like it.

As for dry ground areas, Death Valley in California is very dry, and the Nevada-Arizona-New Mexico-Utah-Colorado area has a huge desert, although just edges of Utah and Colorado, which are mostly higher elevation and get a lot of snow.