I dug up this old jacket pattern I have had for over a year. It was one of those internet free patterns. I have since lost the information to where I found it. :(
Anyway, it's super basic and I am sure you can find an existing one to trace and make your own pattern. I used a sherpa on one side and a similar color pallette on the other side to maximize wearability. I will probably add metal snaps (it's coming in the mail!) because I am terrible at making button holes.