I will go with Gray Rat Snake (Elaphe obsoleta spiloides) also. Could be a Black Ratsnake. Even an intergrade. They are so variable in color/pattern. I have seen Black rats that size with dang near the same color/pattern, and I have also seen the that size that are jet black. I am leaning more towards Gray, because they cover more of Alabama than Blacks do.

Here is a range map:
http://www.dlia.org/atbi/species/Ani...soleta_map.jpg