I echo all the comments here. Delaying the hike and/or starting further south would definitely be something to consider. There are short, steep rocky sections in New York especially that can be very hazardous with just a small amount of snow or ice. It would be hard to get information about those kind of conditions at that time of year because snow and ice can linger on north facing, steep, or shaded slopes when it's melted elsewhere. You don't often hear about these steep, rocky sections from thru-hikers, because memories of the White Mountains and Maine wipe out memories of the much shorter climbs of New York. Of course, Pennsylvania is already famous for its rocks; Maryland has them too, and northern Virginia has a few spots. In addition to slippery surfaces, you can also get substantial snow on any part of the A.T. in March from Georgia to Maine. These big snow storms are less common than they used to be, but even in Harpers Ferry, WV, with our low altitude and quite a bit further south than New York, we have occasionally received 2 or more feet of snow in March. You could luck out some years and see little snow or ice March onward, but there's no way to know ahead of time.
Also to consider: Counterintuitively, snowfall averages are higher as you go south on the A.T. from the mid-Atlantic (south of Front Royal, Virginia), because the elevation of the A.T. increases significantly in Shenandoah National park in Virginia and beyond. Check out the elevation profiles here: appalachiantrail.org/home/explore-the-trail/explore-by-state/Virginia (http://appalachiantrail.org/home/explore-the-trail/explore-by-state/Virginia)(scroll to the bottom of the page).
If you haven't already found this page, check out recommended time frames for some of the more popular alternative approaches for thru-hiking: appalachiantrail.org/home/explore-the-trail/thru-hiking/alternative (http://appalachiantrail.org/home/explore-the-trail/thru-hiking/alternative)
Regardless of what you end up doing, it's commendable that you are considering a variation that helps disperses use and reduces the environmental and social impacts of overcrowding that can occur in Georgia in March and April. When you finalize your plans, the ATC encourages you to register your thru-hike at atcamp.org (http://www.atcamp.org).
You can also request a list of thru-hikers who have done various types of alternative hikes who are willing to share their first-hand experience and advice, by emailing
[email protected]. For more info, see appalachiantrail.org/adviceandprep (http://appalachiantrail.org/adviceandprep).
Laurie Potteiger
Appalachian Trail Conservancy