Long day on the Parkway, and no time for GSMNP
Hello EAC,
From your proposed itinerary, I assume you plan to leave Roanoke on the BRP, take it to Asheville, and then perhaps I-40 to Knoxville at the end of that day. But, you also mention the Smokies, and you note your travel plans are for next week.
Be aware that your approximately 260 mile trip on the Parkway in late October will likely be a very slow day's travel. Posted speed limits are nowhere greater than 45 mph and in some places are 35 or even 25 mph for short segments. Add to that the fact there will be many others enjoying the leaf season (albeit a week, week and a half past their peak by next week), and you're looking at a solid 8+ hour drive from Roanoke to Asheville, with no long stops. If you average as much as 35 mph on a beginning to end of day basis, that's as good as it'll get. I'd assume 27-30 mph if I were inclined to numerous pull-outs, a couple or three short walks, and a sit-down lunch.
Getting off at Asheville misses the Smokies, too, you understand. To continue down the BRP to Cherokee (southern end) is another 90 miles (3 hours, give or take) then a trip into/across the Smokies.
If your intent is to see much of the BRP and the GSMNP, I'd consider leaving Roanoke, overnighting in Blowing Rock or Little Switzerland, NC, and get an EARLY start the next day in order to take the must-see side trip to Mount Mitchell, enjoy Craggy Gardens, and a handful of other great sights on the southern end of the BRP. An alternative allowing you to keep from adding a day to your trip might be to cut down I-77 to US 421, thence west (which, oddly enough is NORTH on US 421) to Deep Gap, picking up the BRP there. Overnighting somewhere like Wytheville or Hillsville, VA, or North Wilkesboro, NC, rather than Roanoke adds 1 to 2 hours beyond Roanoke. In my humble opinion, the BRP from Roanoke to the NC line is the least scenic segment, and getting on at about Deep Gap would give you more time for the higher elevations and more dramatic topography from the NC-VA line down to Asheville.
Safe travels and enjoy your upcoming RoadTrip!
Foy