Some of my friends and I are looking to go on a week-long hike on the AT sometime in mid-March. I was wondering if anyone had good suggestions on a spot in TN, NC, or VA during this time?

If you're in pretty good shape, you could hike southbound from Erwin, TN to Hot Springs, NC. The quicker you get there, the more time you spend in a great trail town (bar, thermal baths, etc).

Mt. Rogers. I did it last year in Mid-March. It was beautiful. There are also plenty of shuttle options and early outs if the weather turns nasty or something goes bad.