you had some great clouds that day to work with. Excellent treatment. Don't know if I would have tilted the frame slightly so the line in the back is level. Most my shots are on a diagnol so I find myself doing this often :)
I love this shot, the colour tones just seems to work perfect for me, love the sky, looks very dramatic. I would not have known that was a train in the background of you did not say so :)