Adding onto @LP08 post about the confluence over the northeast, but when messaging @brooklynwx99 about why the GFS sheared out the storm on previous runs they mentioned how it was running into a wall of confluence, so naturally it would have a hard time holding itself together. I think our biggest concern as of now is actually getting less confluence over the northeast so it's able to have precip get to us, right now the concern is more suppression/shearing than cutting. So when watching future model runs I think one of the most important pieces to look at will be where the wall of confluence sets up over the northeast.
Here are the runs of the GFS and EURO to make that point