If you are willing to drive 7hrs north of central Jersey, the Laurentians in Canada has extensive fatbiking in snow.
46km of scenic rail trail(Le Petit Nord) connects towns and singletrack fatbiking trails, for free. Generally speaking the temps stay cold enough to provide firm fat biking conditions.
And of course there is xc, downhill, and randonee skiing.
This couple was loving the e-fatbikes.
Downhill single track connected to multiuse trail at Tremblant.
Even when its 6 degrees out, people take the baby out for a stroll.
IMO this is the best destination in the Northeast for xc skiing and fatbiking. I didnt bike, but this is the largest trail network I've seen in the NE.