Headed across the Lightning lake from the day lot at 9:20 and started climbing steeply uphill, on several occasions crossing the well-walked trail that traversed the slope. The snow was an icy crust the first ~150m up, them became much softer and easier to hike. At some point we just continued along the beaten path. I was surprised to see such a large number of snowshoe and ski tracks, merging and separating again.
We got to the meadows at 1830m in under 2h and continued on, at times breaking the trail, at times following other tracks.
By the time we got to the base of Frosty, the only tracks visible were those of two skiers who skinned up and skied down the north ridge of Frosty. Shortly before 3pm, we attempted the West ridge. After going 1/3 to 1/2 way up, decided to abandon the idea as the slope got steeper and the sun continued melting the snow on the rocky ridge, making the return unsafe.
Decided to stick to the summer trail on the way back as we were descending the final 400m elevation in the dark, but got irritated with the unnecessarily long switchbacks and cut back onto our own tracks for the final 200m, getting down to the lake at 7pm. No luck summiting today, but a wonderful sunny day in the mountains.