Read moebedick and take it to heart.
I spent (wasted) a lot of my life in the east coast megopolis, and getting around it is a worthy effort.
What he is saying is I-84 to I-81 to I-77. This will take about two hours more and save a fortune in tolls as well. From Columbia south should be no issue. This may not be the most scenic route, but that is just not a good choice in February. If it looks like I-81 might get real bad. (PA used to take pretty good care of it) you can tale I-83 south from Harrisburg, but that will throw you into the Baltimore and DC traffic.
About traveling in February in the northeast. Do not depart without provisions onboard for three (3, tres) days.....
It is easy to get stuck with the roads shut down for a day. After they open back up, you may choose to wait a while more to let the A-holes have their accidents and go home. So, being stopped for 3 days is an easily foreseeable situation. Carry water in bottles because you may not want to de-winterize.
Next important thing...
Traveling like this in less than perfect weather is very stressful for the driver. Even if you are trading off driving (much advised), assign someone in the right seat to be the navigator. Your dashboard GPS still take attention from the driver. Navigator should have the whole set of paper maps (charts) and be tracking the whole time to advise the driver of up-coming situations. If you have a smart phone, you have to have GasBuddy. RVparky is also a good idea. Remember that electronic navigation will only fail if you really need it. (Says the guy that used to wear a name tag that had "Navigator" under his own.)
You did not post ages of kids, but if one can be navigator, that gives less time to disagree with the other. be sure to have planned activities onboard for them both.
Matt
