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Observations

Region: Chugach State Park
Location: Arctic Valley - Rendevous Saddle
Observer:
Date:

Route & General Observations

Typical route to Rendevous Saddle. Thin and variable snowpack throughout valley.

Red Flags

Observer Comments

None.

Weather

Weather

OVC, 23-30 degrees F, SSE winds 15 mph G 26 mph at ridge, (but variable and observed from W in lower locations of valley as it was channeled through mtns). No precip, but started to snow (S-1) at 4pm, with blowing snow and moderate W winds in lower valley and at ridges.

Snow Characteristics

Snow surface

Hard pack surface with ~5 cm new snow in past 24hr.

Snowpack

Variable snow depths and thin over all. Old wind pack observed in most terrain with the new soft snow on top. Larger wind slabs along ridges, at R. Pass, and in specific terrain features such as E ridge of Avalanche Gully. Snowpack had multi-layers of very strong wind slabs and melt-freeze crusts, intermixed with buried surface hoar/facet layers, faceting thick crusts in bottom of snowpack, and depth hoar observed at ground.

Dug various snowpits in area of deeper snowpack with strong windslab component 50 m down from Rendezvous Saddle at ~3450'. Conducted 3 Compression Tests from various pits, all within 20 m of each other. Found similar layers in all the pits but with varying snow depths and recent windslab thickness. Found interesting CT results depending on the wind slab thickness over ~4 cm BSH/facet weak layer that was above a 2cm strong MF crust that had 10+ cm weak facet layer below it. This was all over a very thick and strong crust layer of refrozen facets that appeared as if it was again tending toward faceting and becoming variably weak and crumbly when disturbed. A layer of ~3 cm of depth hoar was at the ground.

Test Results: Note these pits are all within 20m of each other showing the extreme variability in snow depths and reactivity of weak layers in a small area.

Pit 1: Snow Ht = 68 cm, upper wind slab thickness = 6 cm
CTV (SC) down 8cm on buried surface hoar & facet chain layer

Pit 2: Snow Ht = 89 cm, upper wind slab thickness = 12 cm
CT11 (SC) simultaneously on both facet layers surrounding the MFcrust - down 15cm on same BSH/facet layer & down 19cm on facets below crust

Pit 3: Snow Ht 110cm, upper wind slab thickness = 30 cm
CTN
Wind slab was very dense and thick in this pit

Did not have time to conduct any ECTs in this snowpack.

Photos & Video

Photos



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