Avalanche: Chugach State Park

Location: Eklutna

Date:
Observer:
Avalanche Details
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Trigger Foot PenetrationRemote Trigger0
Avalanche Type Hard SlabAspect Northwest
Elevation 3600ftSlope Angle 40deg
Crown Depth 24inWidth 100ft
Vertical Run 350ft  
Avalanche Details

On 2/25/18 two skiers ascended to a pass west of West Twin and Goat rock. From the pass the 2 skiers descended 1000 ft, transitioned and ascended the northwest aspect of a 40 degree apron bellow a north facing couloir. While boot packing roughly 100 ft from the base of the couloir, the slope released, whumphing loudly and breaking 10-20 feet above skier one and two. Both were able to self arrest after traveling 100-200 ft down the roughly 350 foot long, 75 foot wide path. Snowpits before and after the slide revealed poor structure. The slide failed on the melt freeze crust and had a crown height of 1-3.5 feet. The culprit layer failed to propagate in pits dug before and after the slide, crumbling at ECTN 23. The flanks were 1 foot deep. The undisturbed snow height at the toe of the debris was 110 cm. The depth to ground from the deepest debris was 250 cm.

Overall, we half-wittingly placed a massive amount of trust in a rotten snow pack that was not shy about giving us negative feedback. The signs were there, we just couldn't bother to listen. Springtime and a more stable snowpack are just around the corner, but such a measured perspective and any semblance of deep though were completely absent on this calm bluebird day.

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?No
Collapsing (Whumphing)?Yes
Cracking (Shooting cracks)?Yes
Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.
Weather

Blue skies, 5 to 15 F

Snow surface

Faceted powder

Snowpack

Pits showed extremely poor strength and very little cohesion in top 1-2 feet.

Photos & Video
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