Where do you presently reside? The trail conditions and weather are perfect right now. Strangely, we have had no rain since spring, and the trail is normally somewhat covered with remnant snow by now at high elevations, but presently it is amazingly clear. You won't find better conditions than we have at the moment. If you're all in shape and ready to go, you might pull the trigger early. I know December is a busy month and it sounds like you will be traveling, but it's a possibility. The reason Ellen gives you such an "iffy" response is that all of us locals who have done the trail many times have learned to take it on a day by day basis. There are truly a lot of ifs. In general, if there have been only light rains and a few days of sunshine before your hike, the trail may have been broken in again by someone. If you're going the day after a big, cold storm, the route will be invisible above the traverse. I know the route well, but I have gotten up to a suddenly solid line of snow and simply turned around. So you are wise to try to plan for the highest chance of success. Fall is the very best time, but spring is good as well. March and April offer you very good opportunities to make the hike. If you're traveling a significant distance, I hope the weather cooperates with your plans. If not, you can always do a Cactus to Flat Rock, retreat, Long Valley to San J summit adventure. After all, an adventure without obstacles is fun in the doing but dull in the telling. If you end up with a story like, "You're not gonna believe this! California had exactly zero rain in this rainy season until the day before we went, then we show up to find a clear trail replaced with feet of impassable snow! It was crazy! We still made the peak, though, check out these awesome pictures!" It's all about the adventure, and any friend who understands adventure would probably relate to the story of an event that was unpredictable and trying more than an easy success.Keep posting and we'll keep updating.
z