In Wisconsin, I'd like to say that it would be great in the Wintertime, and I have worn it several times in the winter, but, it's more of a Fall/Spring jacket. With the Orion liner, holy cats, you can't tell that it's 30s-40 out. It feels like 60. It's that nice.
WIthout the Orion liner, it's comfortable in 40's weather.
Super nice, got lots of compliments on it. Very comfortable. I bought 2 more Constants for myself during the sale that they had going on.
Love it. Would absolutely buy it again, and absolutely recommend it for my Shazamin' taste!