Snow Peak Avalanche

Avalanche date/time

Saturday, May 4, 2019 at 08:30

Number of avalanches in this report

1

The size of avalanche

2

Slab thickness

40cm

Slab width

200m

Run length

600m

Avalanche Character

• Wind slab

Trigger type

Skier

Trigger subtype

Accidental

Remote trigger distance

200m

Start zone aspect

• S

Start zone elevation band

• Alpine

Start zone elevation

2,730m

Start zone incline

39°

Runout zone elevation

2,300m

Weak layer crystal type

• Storm snow

Crust near weak layer

Yes

Wind exposure

Cross-loaded slope

Vegetation cover

Open slope

Snow Peak Avalanche - Sat Mar 4 8:30am. Size 2 skier accidental. 3 involved, 1 caught for 10m before getting free, the 1 trigger skier was able to self arrest immediately, 1 not caught. Windslab on thick sun crust, crown 40cm+, propagation ~200m across and 60m up. S-SW aspect at 2730m - crossloaded. Triggered on steepest slope along the ridge about 60m below summit - slope angle just under 40deg.

We had a few small cracks and a whumpf before the avalanche. The slab seemed to be bonded well lower down and was much more shallow, we all agreed to continue. It got deep quickly higher up and clearly the bond was poorer, and it failed at the "crux" of the climb. Propagation was impressive, 2 skiers were more exposed to the slope than they initially thought. The slab took what felt like ages to gain momentum, which was a good thing. In hindsight, trying 1 more kick turn after the whumpf was unnecessary, since we knew we were on windslab and were given enough instability clues. We had already decided earlier during the climb to not ski the southern bowl feature that ended up sliding since we didn't trust it.

Our communication throughout was fantastic, and ultimately resulted in nobody getting fully caught. There is a fine line on Snow Peak between exposing yourself to this southern avalanche slope, and exposing yourself to the massive overhanging cornice on RH side. We were probably too far left today, and triggered an avalanche to let us know! We all agreed that the feedback of triggering the slope was helpful long term, since typically nothing slides and it subconsciously tells you what you did was "safe". This will provide a bit of a mental reset for our group, and perhaps we will turn around earlier next time since it was a bit too close today. The clues were there, it was up to us to listen. Hope this helps. Stay safe out there.