We toured to Symphony Lake from the South Fork Eagle River trailhead. Sunny warm day. No red flags. Firm snow.
We saw many old avalanches along the way, most have already been reported here over the past 1-2 weeks. But, debris in Hugh’s Bowl was really impressive. Solidly a D3 slide (can bury or destroy a car, damage a truck, destroy a small building or break a few trees). Several trees with trunk diameters ranging from arm-thick to thigh-thick were in the debris pile. I guess that the main slide happened around February 18th, and the wet slide happened in the days after that.
Lining up photos we took with Gaia maps, I estimate that the crown was 800-1000ft wide. It ran 1,800 vertical feet. The debris field was roughly 2-300 yards long and wide. The debris field over ran previous skier and snowshoer tracks. The alpha angle was measured at 24deg.
approaching a section of wet slide debris that overran the larger slab debris.
examining broken tree trunks
Crown highlighted in red. Crown connected across both chutes. There is still a lot of debris behind where this photo was taken.
previous tracks buried 4-6ft deep.
measuring alpha angle to the crown, final measurement 24deg, confirmed with topo map