May 25th. Started late (11:45) Lone Pine was at about 65 Degrees, light wind. Trailhead was mid 50's.... Mirror Lake was about 35 degrees @ 3pm. (This is a good water fill up site).
Did not need snowshoes, but there is plenty of snow from about one mile below Mirror Lake. I recommend Crampons. Bring an ice axe and knowledge of how to use it, especially for glissading down. Our group of 4 had two relatively new to hiking in snow/ice. By the time we got up to trail camp (6:30) the temp dropped dramatically. Wind was up around 20mph with frequent gusts 40 to 50, which made for a loud cold night. (approx. 10-15 degrees F) . So it is still the season for bomber 4- season tents with vestiuble, insulated mats, snow shovel & liquid stoves (bring a wind screen). Also bring full gaiters. One member soaked a boot and his toes at camp were entering frostbite. At daybreak the wind was blowing and the chute was barely visible. Wind at the trail crest brought in more danger so the summit will wait. Should be plenty of snow on the chute through June... good luck.