Avalanche: Chugach State Park

Location: O'Malley Peak, NW Buttress

Date:
Observer:
Route & General Observations

The slab that released was located on a small bench above a pitch of water ice/cliffs, O’Malley Peak, NW Buttress.

Avalanche Details
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Trigger Foot PenetrationAvalanche Type0
Aspect West NorthwestElevation 4300ft
Slope Angle 30degCrown Depth 24in
Width 40ftVertical Run 35ft
Avalanche Details

After climbing up a pitch of ice on O'Malley Peak, I pulled myself up onto a snowy bench. After taking a couple steps on the slab, it cracked, separated, and began to slide under my feet. Ultimately, the whole snow shelf (40'x35') just broke off and fell. I had to quickly climb off the top of the slab as it fell over the crag below, very high consequence fall. Thankfully, I was at the top where it separated so I was able to scramble off by the time it had traveled 3-4'.

The slab itself was hard and about 24" thick at the crown and narrowed to roughly 14" at the bottom. After it fell off the crag, it continued down the runout above Deep Lake (stopped within 200 yards of lake). It did not cause secondary slides.

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)?No
Cracking (Shooting cracks)?Yes
Observer Comments

There weren't any obvious signs of instability from the start (no avy debris in the area at all). Snow did feel quite weird underfoot though.

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.
Weather

20mph winds, maybe 3-4 inches of accumulation the week prior, temp was 20*F

Snow surface

Slab had powder on top(8-10"), then more of a styrofoam texture at the base.

Snowpack

Did not test prior to climbing.

Photos & Video
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