Seriously, I'd leave at 4 am, you might stand a chance.
Or, leave at 6 pm the night before..... which was my strategy for my August trip a few years ago. I drove 6 or 7 hours then check into hotel..... then drove 12-13 the second day.
I have had no luck in that area, any time of day, on any trip. I've managed to miss traffic directly around DC, but those carpool lanes get me every time!
You'll have to look on a map for this , but, I have gotten off the highway just north of Wash DC and taken route 301, it's a great route and will help you avoid that traffic. I found that one time 95 was CLOSED because of an accident.... it was a great find.
I live in Orange County, NY, bordering NJ, near Sussex County, so our trips are similar.