I just looked more into the wind/flow and all the snow profile is NW flow behind the FROPA. It’s not like an east flow coastal.
10AM Sat on 18z GFS. You can see the ESE flow is under the warm air at 850mb, not snow profile. Then where wind streamlines go NW behind the front is where it starts snowing.
You can see the frontal position in the streamlines. Looks like everyone will need wind to go NW in this to flip to snow. Anyone seeing E/SE flow will be in the warm sector and N/NW will be cold sector. Both here and there, it’ll start snowing when the wind goes NW as the front will be through.