Just returned from a 4-day 3-night out and back from onion valley, with a rest day for good measure at Kearsarge Lakes. We brought a hammock and fly fishing rods and focused on drinking in the incredible surroundings over making miles. Overall conditions were great:
Temperatures: in the 60s-70s during the day and 40s at night
Snow: Seeing some patchy snow just makes things more beautiful. There were two small sections of snow to cross coming up from onion valley, but easily passable in the afternoon - hiking poles were nice to have.
Mosquitos: Definitely present in the morning and evenings at both Kearsarge and Charlotte lakes, and pesky enough to make dinner a short affair. They were mostly a non-issue during the day.
Bears: We heard reports of a momma and three cubs making themselves known around Charlotte and Kearsarge lakes but we didn't encounter them.
Fishing: Fly fishing the lakes and streams was so much fun. We caught lots of 6-8" brook trout in the Kearsarge lakes, and some 8-11" rainbow trout in the streams coming out of charlotte lake (but the mosquitoes there were a 3-4 during the day)
Meals: I love backcountry cooking, and my chicken pad thai experiment turned out to be a huge success. The pork ramen was only so-so, as it turned out to be closer to ramen with pork jerky (the rehydrating didn't go as fast as desired). I have been putting my dehydrator to use and all the meals were wonderfully vegetable heavy. I haven't learned portion control yet though, so I need to work on not cooking for 5 when there are only 3 of us on the trip... it was a struggle to finish some of the meals
We drove in from the bay area on Friday, and at the last minute we opted to stay at the Bed and Breakfast in Independence instead of at Gray's Meadow campground due to the 100+ degree weather down at valley level. Onion Valley campground had been closed due to road damage, and still didn't have water available. That ended up being an adventure of it's own - for the reference I'd pass on the Winnedumah BnB if you've got the option.
Day 1: Onion valley to Kearsarge Lakes. Easiest way into the Eastern Sierras or not - this was a lot of up on the first day, and we hadn't been able to acclimate much. The views made it well worth the sweat. Day 2: Kearsarge Lakes - We did a lot of fly fishing, napping sitting in the hammock, and going into the very cold water. It was glorious. Day 3 Kearsarge to Charlotte Lake. Day 4 Charlotte Lake out to Onion Valley. We heard reports that Glen pass involved some tricky snow and boulder scrambling, and decided to skip it this trip. Mentally planning the next trip already.
Huge thank you to everyone on this forum for all the fantastically detailed information. This community was a big part of researching, route planning, and idea brainstorming, and it is hugely appreciated.