Not skilled enough to tell you what's driving it, but 12Z Euro takes the primary low for this weekend over Chicago. Perfect (for me at least)
Edit - looks like it does pop a secondary albeit later than previous runs, and would still be a rain > snow solution for me verbatim.
I'm admittedly overly invested in this system for personal reasons and rooting for a rainy solution for Southern ME. I wouldn't normally comment on models, but since it's just 7 of us plus 4 moose who care, i'm doing it.