This will now likely be an impactful storm system region wide featuring mod-hvy snow, coastal flooding & power outages w/the highest impacts still focused on the N-Mid-Atl, LI into extreme SNE, with room for this axis to adjust further NW. There are two primary reasons for this:

1) Moving up in time on NWP, the Pacific ULL has remained robust & has retrograded=Constructively interfering & engendering a notably amplified W-US Ridge. 2) Today's departing NE storm is moving out quicker, giving room for significant EC height rises. (increased wave spacing)

The GFS doesn't often win many prizes, but in terms of catching onto the synoptics, it has done an admirable job here. I suspect this is partially due to its propensity to be more progressive w/northern stream branches than its counterparts, which are still catching up IMO.