Just went that route the first part of June on our way to Fort Wilderness at Disney. There are sections with a third lane for trucks that will have to climb really slow. My truck sure had all it wanted getting up a couple of them at speed. The fog is the real danger in summer most of the time along with crosswinds. We stayed overnight at the Fancy Gap KOA and the fog was thick enough to cut with a knife that morning. On a clear day the view coming down into North Carolina is stunning. We had pea soup. Also the highway in NC was so bumpy that the kids dubbed them the worst highways of the whole trip! We took a different route home (via the Smokys) and the DS noted, thank goodness we don't have to go through NC again. LOL