Time for some premature extrapolation speculation and contemplation - caveman drawing style.
12z Euro used for illustration purpose.
I've tried to put it into one image - all three main ?'s I have to where this may lead. The southwest shortwave, notice it's trying to "come out" across TX panhandle - Euro bias of holding on too long?
Upper MW vortex - which route does it take, it could go either way based on,
The separation between the post Xmas storm vort and the UMW vort - if enough separation, heights can rise as UMW shortwave would tend to maintain within the developing trough. That would also depend on the SW vort and the timing and track it takes across the deep south (gathering another boat load of GOM moisture as it does so). Adding that if the UMW vort does dive more south than southeast, its absence would allow decent High Pressure in it's absence - available to further drive the 850 line even further S.
These 3 things - not much more ATTM, have me pouring over various ensemble products to see if there's an indicator of any "clear winner" solution.
Thanks - I hope others find it, at least, somewhat worth the contemplation. I'm no "fancy Cranky", but I do try. LOL
From scrolling the ensembles (mostly the NCEP product), to my amateur POV, the post Xmas storm seems to be on the fast track out of town. That "needs" to happen to vacate the N Atl to allow the heights to rise as the "pebble in the pond" UMW shortwave dives into the trough. (if the post Xmas storm tarries, then the UMW vort may "feel" it and move more southeast than south).
If/when that dive happens, it times to link with the STJ vort - then the heights to the east can rise further enhancing whether the trough can swing negative.
We've not seen a situation, outside that SE US paste job a few weeks ago, where we get a fully charged closed low situation - both vorts co-mingling) but this set up is pretty decent in that respect.
I didn't mention the western side - the ridge seems adequate enough to do the job (of further influencing the trajectory south of the UMW vort). I don't see a problem there, at least not at this point.