Idaho is kind of strange compared to most states that I have been to, and I've been to all but two of them. Seems like most have different halves, going east or west. Idaho seems to be very different going north and south. I can easily see the northern part of the state being included in the PNW, but the southern part of the state is very desert like, much like Nevada is. I'm only 35 or so miles east of the WA border, so maybe that makes a different. The further east I go, the thicker the forest gets. So actually, parts of Idaho look more PNW-ish than parts of WA and OR!