Can anyone relate this to the last big snow year (2011)?
Looking at the snowplot, it looks to be on an all time curve 2017 Snowplot
Yeah: go back to that site, check 2010-2011 and hit the "Draw Chart" button, and the result is that current average snowpack in the South, including MT Whitney, is exactly on 2011.
Definitely not "all time". Rainfall maybe record, but with all the melt already, remaining snowpack is not nearly record. That said, definitely deeper up high elevations: the charts are only broad averages.