MLK... leave early or wait

Like many of you, I've got a school aged kid. We're going to ski this weekend with his buddy. I know, I know. " Madhouse... Ski some other weekend. Ski during the week." But I'm not gonna take the kid out of school, so that's a constraint. He gets out of school around 2:30. Thoughts on leaving from the Boston area? Leave at 2:30 and TRY to beat the traffic. Or wait it out, have dinner at home, and go later after traffic calms down?