No. Jetstream is more of a shell. Not much insulating properties. Think of the Atom as a light puffy. I’m not against shells, I just don’t think it works for me. If I were hunting more in thick cover where a puffy may get ripped, or dealing with showers or more wet conditions I’d use one. You mentioned December out west, doubt you’ll be dealing with any rain so I’d focus on warmth. But if you want a more robust outer layer, the Jetstream is probably a good choice. I just tried a Kuiu Axis hybrid, liked the jacket it just didn’t fit me. Sleeves were too long relative to body size.
