Very rare coming from them, only a handful of times I can remember them outlining significant tornado risk. We can easily have a 10% hatched risk and all we get from their AFD is "there might be a spin-up tornado."
A couple notes about the latest data out of the HRRR. I see a couple factors that could limit the threat and could also locally-enhance it, especially over northeast Alabama and northern Georgia. My main point of focus is possible early day convection. Models diverge on how much convection may be ongoing on the morning, with HRRR showing an ongoing, decaying MCS moving through the AL/TN/GA triple-point in the morning, followed by sequential waves of QLCS storms with embedded supercells. If early-day convection sticks around more or is more substantial than forecast, it could mute the threat, particularly with northward extent. It's really common for cloud cover to linger, even without precipitation, across the foothills of the Appalachians in Georgia, keeping instability at a minimum. That could happen here, and would likely cut off far northern Georgia and much of Tennessee from a more significant threat.
However, I could also see this setting up some boundaries that enhance kinematics in a corridor just north of I-20. That would be a pretty big problem, with Birmingham and Atlanta, two of the biggest metropolitan areas in the Southeast, basically being in prime territory for tornadic supercells, should such a scenario materialize. Possible discrete convection out ahead of the main QLCS Wednesday evening could result in constructive mergers that further encourage tornadogenesis. There's also a possibility that precipitation decays quickly and destabilization occurs all the way into southern Tennessee. However, generally I find that models struggle with handling the evolution of leftover, morning-after storms, like the ones that will probably be ongoing tomorrow morning. Either way, I think the threat is conditional but quite substantial anywhere from Jackson, MS, all the way east through Birmingham to Atlanta.