One thing to keep in mind is that a lot of people ("leaf watchers") are driving around the backroads that time of year, and they're probably paying even less attention to the road than normal.

The fall colors are lovely well south of New Jersey, even though New England and Quebec are better known. Eastern North American has the world's great deciduous forest. Obscure fact: There are more species of plants native to Smoky Mountain National Park in the southern Appalachians, than on the entire continent of Europe.

I would think that the GAP Trail would be magnificent for fall colors. There's an active maple syrup industry near Meyersdale (Somerset County?) along the trail. Sugar maple trees typically have the most vivid leaf coloring of all the trees. The C&O Canal would be nice, too, if it's not too muddy.