This is an awesome photograph and is one that I have looked at for a while now. I love the variation of the blues in the sky contrasting with those of the whites and greys on the ground.
However, I do feel that the image gets a little lost over to the left hand side. Personally I would have cropped the image at the edge of the trees leaving invisible lines of force from the row of trees on the left and the road on the right. Although there would be loss of part of the dramatic line of clouds it would still make the image more balanced.