Another Snake Post

We don't often see snakes close to the house, but one evening a few weeks ago, Dan spotted this one right on the front porch.   I took this picture through the window, so it is blurry, but you can see it is not a garter snake.  It was much bigger than the usual garter snakes we see.  After looking at pictures in a book, we think it might be some kind of a rat snake.  When I opened the door to take a better picture, it took off around the corner of the house.