Miller Ridge area, Pemberton
We went out this morning with the mindset that the new snow + wind would have created some touchy avalanche conditions. We’ve also been keeping an eye on the Dec. 9 interface which is a melt-freeze crust in some areas but rife with Surface Hoar on top of that crust in others. What we found was a very reactive storm and windslab showing full feature propagation with crowns as deep as 120cm, all failing on ~5mm surface hoar that’s been incrementally buried this week.
We skied very low angle terrain with small slopes at the entrance off a treeline ridge feature. So even though these slab avalanches went “full feature” we were keeping the terrain very small and low angle. We triggered two avalanche up to sz. 1.5 on E-NE aspects on 27-32 degree terrain...lower angles than usual, perhaps, but it just goes to show how touchy this layer can be.
Be very careful of all open slopes at treeline elevations where surface hoar may have survived. We decided to leave the field due in part to these observations but also deteriorating weather.