I assume you mean in winter. I parked at the Flume Visitors Center, walked up the bike path for about two minutes, and the Mt. Pemigewasset Trail trailhead was on the left (the trail goes under 93). I believe it's 1.8 miles from the trailhead to the summit via that route.
There's another trail that leads to the summit from the south, but I don't recall there being a plowed parking area there last winter.