I'm going to have to chat with Ned Tibbits - he's done Kennedy Meadows to Muir Trail Ranch this spring on MSR Ascent snow shoes (no sled). He recently posted about that on the JMT mailing list.

pix from the first half of their May 10 - June 15 trip here which ended at Onion Valley.
http://www.facebook.com/album.php?aid=35009&id=157155614308934

part two is later in June it appears - starts out with a heli rescue before Kearsarge Pass, then takes you back on the JMT northbound past frozen Rae Lakes and generally spring-like conditions most PCT hikers run into
http://www.facebook.com/album.php?aid=36078&id=157155614308934


and based on what I am seeing, even in May there was a ton of snow. Maybe going in late April through early May without sled is the way to go, or bring a mini-sled to supplement the pack where it is possible. Forester looks gnarly even in May, and there's no way I'd be pulling a sled up that thing.

I am hoping to beat the melt and find the conditions these ski bums encountered in 1992 but I can't get a time of year from the text:

http://www.jamesalutz.com/index_JMT1.htm

Also - resupplying at VVR isn't so bad detour-wise - I usually head that way in the summer anyway, sometimes taking Goodale Pass instead of Silver and no ferry. That way I can also bypass the Bear Ridge switchbacks as an added bonus. I actually know the Bear Ridge Trail better than the regular JMT in that area.

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