Earlier this month, Tomer Burg (PolarWx) on Twitter posited that DC - NYC could see something on the order of ~20" for the month of January and people laughed at him. He might be right.
12z GFS is a reasonable "fail" scenario where the shortwave doesn't eject cleanly -AND- the confluence to the north is stronger. Even with that in mind, it looks like a solid plowable to warning level snowfall for the entire subforum with no temp issue - and it's on a weekend.
It's absolutely beautiful. CAD Signature all the way to interior South Carolina, moisture laden storm, banana high from Quebec down to Texas. This is perfect.
Standard Disclaimer: RE: mixing
To keep from and mixing, we do not want to primary low running too deep into West Virginia. Also would need some sort of coastal transfer to lock in cold air east of the mountains.
Thursday looks like the only "warm" day and that's upper 30s/low 40s. The rest of the week looks primed to keep the ground cold. High in the 30s, lows in the mid 20s.