Looking at the snow levels across the SoCal ranges and the Sierra Nevada, it would actually be 100% reasonable to start a thru-hike TODAY? Anyone game? 
One could take a leisurely pace, reaching the Siskiyous (probably the first place that has very difficult snow) in late May when the melt is starting. You’d have to really take your time, but if you ever wanted to try a 7 or 8 month thru-hike of the PCT , this is your year!
Of course i’m only half serious. The short days and cold nights would be difficult. There’s still an excellent chance that the Sierra will get some huge storms in the next 3 months, stalling your thru-hike for a LONG time. And even with the exceptionally low current snow, there are surely still a few high passes that would be covered and dangerous. But it does catch one’s imagination to start early, doesn’t it?
happy hiking…
markv