I just spent a very pleasant and informative hour or so playing with the historical and current snowpack curves at http://cdec.water.ca.gov/cdecapp/snowapp/swcchart.action
and I highly recommend it. First, the site is interactive: you can add and subtract years and reset to get the comparisons you would like to look at. If you last hiked the trail in say 2011, the year Mile, Mile and a Half was filmed, or if you have seen the film, you can select that year, click the " Draw Chart" button near the top on the left, and it will add that curve.
You can then find your date this year and see what the snow was like that year on the same date. (The film starts about July 10.) A couple of other details are worth noting. Look at the monster year of 1983, your index year, the average year and say 2011 and you will probably note that they all zero out at about the same place, about mid July. In fact, the monster year of 1983 looks like it zeros out earlier than the average year and some of the index years I looked at, like 2011 and my trip in 2013.
Another interesting thing is that things have definitely changed in the last few weeks. A month ago, we were right on track with that monster 1983. Now, we are looking like 2011. In fact in the north, this years curve has caught and crossed below 2011. Moreover, the only year I could find in which the actual peak snowpack went much beyond April 1 - into May in fact - was 1983.
So I will sneak a few inches out on a limb here and offer the following. I think things are looking up. Oh I know there is another dump going on right now up north, but central and south are looking better. And anything can happen between now and next Tuesday, never mind June, But based on the curves I am looking at, I do not expect everything to get pushed out 4-6 weeks over an average year, even if something does happen. Why? A purely technical analysis: those curves are not parallel: they all begin and end at roughly the same points: big snowpack years do not tend to start earlier and end later; they are steeper at each end. So yeah, the melt and runoff are gonna be pretty spectacular, and June 1 will be deep, but the differences between snow pack on a given date in different years will get smaller and smaller until they disappear on or around the same date year after year. Or that is the trend, the tendency.
Yeah I know, the sno-tels are only in certain places, and those places are where most of the land is: they are not in the passes where the going is toughest, and snow will hang in those passes much later than indicated by the overall snow pack curves. But the sno-tels are where most of the trail is, so I think this is a pretty good indicator of what most of the trail will be like. Oh yes, the passes will probably be motherbears all summer, but thats a lot different from projecting that most of the trail will involve snow travel for most of the summer.
So, bottom line prediction right now: June 1 to August 1 looks like 2011, not 1983.