Long Trail in March

You'd be passing the top of about 8 ski areas which might give you an idea of just how much snow you'd encounter. I even ran into 2 1/2 feet of snow on Glastenbury during the 2nd week of May this year.

I don't know if anyone has tried the LT during that time of year, but it's difficult enough during the summer.

I did most of the LT in May becuase thats when the trail 'opens'.
The GMC doesnt want people useing the trail during "mud season" because it erodes the trail. The day after Memorial day is usually the end of mud season and the start of black fly season.
The time of year your talking about can be unpredicable year to year but I would expect freezing rain, freezing nights, some warm days, and travel on slush and ice.
more info at greenmountainclub.org
The GMC's Longtrail map is awsome.

My experience mirrors the other posts – weather gets tremendously variable… can range from rain in the 50's to below 0 in one 24 hour period. Can also still get big dumps of snow – bring your snowshoes. That said, if the snow cover is consolidated and nights are below 20 or so, and if the trail is broken out, you can cover ground like no other time of year – at least until it starts to thaw later in the afternoon. The alternate scenario is the warm, foggy night that saturates (rots) the snow creating conditions where you're sinking into wet mush every step. Uugh. It's entirely weather dependant.

I also have a break in the Winter too. I suppose the winter snow cover would remain and there would be lows of about 0? or lower?