Where in the DC area? Being in NoVa would add an hour, maybe two, as you may depart in the morning rush. You will also hit morning rush hour in Baltimore. I would allow a bare minimum of 4 hours. With the likelihood of delays on the Outerbridge Crossing/ SI Expressway/ Verrazzano, you're looking at a possibility of 6 hours. If you can get there without driving, do it!