Hi. We live in Western PA and have traveled the I77 & I26 to I95 route many times. We often leave for Florida the last week of January. Because of some weather issues last year, we took a different route.
Last year we went east on the PA turnpike and stayed on I70 exiting at Breezewood. When I70 comes into Maryland, we exit and follow US 522 to Winchester VA, then on VA route 37 south to I81, to I66 east, to US 17 south to I95 south near Fredericksburg VA. This route usually sees warmer temps because it is closer to the coast. It is also much easier on the RV engine requiring many fewer downshifts for hill climbing than I77. The downside to this route for us is that it adds about 90 more miles and about 1.5 to 2 hours to our trip to the Orlando area.
Best wishes on your trip.