Observations

Tuckerman Ravine

January 6, 2021 at 11:00 AM
Name: Jeffrey Fongemie| MWAC
Location: Small south facing slope between Lip and Right Gully, low in the ravine. AKA Chicken Rock Gully

Few clouds 27.5F air temp. 2-3cm snow overnight. Wind from north. Light (very) snow transport could be seen early in the day at the ridge tops accompanied by light sluffing down the ice cliffs of the Lip area of the headwall. Snow transport ended around noon. New snow drifting into small deposits here and there could be found, mostly firm existing snow surface with what looks to be textured scoured surface up high in the ravine. Some gullies are filling in, but snowpack disconnected from Center Headwall to Right Gully by rocks and ice.

Evidence of avalanche debris was found on the ravine floor right side. This debris was largely re-covered by new snow and was frozen hard and mixed with dirt, likely the result of a wet-loose avalanche during the Dec. 25 4″ rain event.

Further up closer to the corner known as the Open Book ice climb we found clean, dry slab avalanche debris. This too was weathered with size estimated to be small D1, no crown visible, which may have occurred during the Dec 29 storm which brought 8-10cm new snow to the ravine.

At our snow pit location with HS 95cm to ground, we found an overall right-side up snowpack progressing down from 4F+ to 4F -to 1F through roughly 30cm of melt-freeze (Xmas rain?) and ice at the ground level.

Stability tests: CT2, CT3 both at 55cm. ECTN11 at 30cm. PST ARR 68/100 through the weaker layer at around 55cm.