What in the world is an inversion? It seems every year in the Boise basin when we look out our windows, those of us that have Vista views ( and I'm not trying to be a snob), we see smog. Everybody talks about that as being an inversion. I recently had a conversation with Natural Resources Conservation Service water specialist Ron Abramovich about snowpack and he made several references to inversions so I asked for a little more explanation. "An inversion is when cold air falls into low spots like valleys such as Boise."