We followed the Rainy Lake trail, which is shown as an old, unmaintained trail on the Green Trails Mt Si map. Until we hit snow the trail was easy to follow except for where it was obscured by large numbers of blow-downs. Snow patches started at around 2800 feet and by 3200 feet we could no longer see the trail because of the snow cover. At this point we used our maps, compasses, and altimeters to make our way to the lake. The lake is set in a basin with some nice cliffs, it was mostly frozen. The trees on the ridge above the lake had fresh snow on them. On our way down we caught some excellent views of Garfield during cloud breaks. As we returned to the trailhead we were surprised to meet two different parties on their way up.
Trip type: scramble
USGS quad: Lake Philippa
In: Middle Fork Snoqualmie Drainage
Reference: Middle Fork Snoqualmie website
Car-to-car time: 7 hours 30 minutes