Since you specified the two areas you are most interested in I thought you might like to know about these additional links:
Forest is in Bedford County:
Elliston is in Montgomery County:
Where you will be is nothing like Boston, thats for sure. Boston has some frigid temperatures and some serious snow fall. You may get a dusting here but I haven't used a snow brush or snow shovel since moving here from up north. I'd say it may be similar to SC depending on where exactly you were.
Roanoke is right between Christiansburg and Lynchburg, and I can tell you that we are a "four season" area. Summers average about 80 degrees, and winter averages about 40 degrees. We do have some snow in the winter, but it usually does not stay around for long.
The Christiansburg area is at a higher elevation so there is a bit more snow there in the winter, and it is a bit colder in the winter and also cooler in the summer than Roanoke / Lynchburg. It can get a little steamy around here in the summer, but maybe not quite as intense as some parts of South Carolina.
Here are a couple of helpful links:
I hope this helps.