I don't know what TV Mets were talking about. Just a quick glance of the total accumulated rain totals from three days ago until now on the GFS, I only see maybe 2 out of 12 that show an isolated 4-5" total anywhere in North Alabama. Most all show 1-2" average.
I do know that convective complex yesterday morning near the gulf may have cut off some moisture transport but it there was ample moisture in the atmosphere regardless of that. I don't watch TV mets, but what I've seen predicted by the models and the NWS has been fairly accurate.