Front Range

Avalanche

Loveland Ski Patrol · Nov 26, 2018 · Front Range

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Weather

Clear, 2F deg, Winds 15-20 G35 WNW HN24-None.

Snowpack

Basal Facets, 2-3mm in size, up to approximately 30cm from Ground. A thin 5-8cm, pen hard wind slab in exposed lee areas just above the basal layer, but softer, 4F, in protected lee pockets. An NSF layer above this thin lower/older wind slab. Above this a 1F to P hard wind slab 10" to 4' thick, depending on terrain features.

Avalanche

Upper OTR, North facing, 11,800', initial detonation of simultaneous explosives, one 4# and the other a second later 7#. HS-AEc-R3-D2.5-O/G. Second Avalanche Zoom Sleeper, North facing, 11,450' triggered sympathetic with Upper OTR debris running over it, HS-R2-D2-O/G. Both slides started on the thin wind slab then stepped to ground. Both slides propagated into terrain with medium size trees and deeper slabs. Zoom Sleeper had been controlled with explosives producing a previous avalanche the week before Thanksgiving, this path had been ski cut and compacted with ski tracks. The gradient clearly continued to rot away the facets under the thin slab formed by the 2" and wind that preceded the Thanksgiving Storm despite ski cuts and compaction.