Vail & Summit County
AvalancheArden Feldman, Jason Konigsberg · Feb 20, 2018 · Vail & Summit County
Weather
Light snow throughout the day with obscured skies beginning to clear during the evening. Cold with temps in the single digits and generally calm winds other than some light gusts near tree line.
Snowpack
3-6 inches of new snow. We dug on a NE aspect near tree line, near the crown of a recent very large avalanche. Found a 1 meter deep slab up to pencil hardness resting on 40 cm of weak facets and depth hoar. ECTX result but the adjacent avalanche shows that test results are not highlighting our deep persistent slab problem. We also dug on a SSE aspect below tree line with a HS of 70 cm and found the recent snow sitting on a thick crust that was very poorly bonded to underlying facets. Not a significant concern at the moment, but it could become a problem given a large load.
Avalanche
We checked out a previously reported, natural, very large, deep persistent slab avalanche on a near tree line, generally east facing slope. R3-D3. It likely ran sometime in the last week. The crown averaged 4.5 feet deep and was up to 5 feet deep in spots. It ran on weak facets near the ground. It was at least 500 ft wide and had an impressive debris pile.