Looking back at the 06z GFS, it is a two-part storm in N Virginia. 3-5” while flirting with the mix on the front and then a 4-6” thump on the back.
We can derive a realistic best and worst case scenario for DC. Best case is that the front end thump is robust and we get the GFS/NAM solution on the back, which could mean 12”+. Worst is that the front end is drier/warmer than we want, and then we get the Euro scenario with nothing on the backside (2-4” frozen).