Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Possible
- Größe
- 1–2
Recent Avalanches: It's been 9 days since the last reported human-triggered avalanches. Which were a cluster of three remotely triggered wind slabs in the Seattle Creek area in Turangain Pass. In the Summit Lake area, the last human-triggered avalanche was a month ago.
The Summit Lake area has been in a major snowfall drought so far in December. Our last measurable precipitation was December 7th, and the last known significant human-triggered avalanche was November 22nd. This lack of any significant weather is causing our snowpack to enter a mostly dormant phase, with cold temps causing weak snow to form in the snowpack but otherwise little activity with buried weak layers.
However, Summit Lake has seen much stronger and more frequent winds during this prolonged high-pressure weather. Which, when combined with a weaker and shallower snowpack, means human-triggered avalanches on stubborn wind slabs with weak snow underneath about 1' deep remain possible. This type of setup is most common along ridgelines and convex rollovers, but since wind-affected snow is widespread in the alpine, a pocket of wind slab could exist in atypical locations. You can look for stiff and hollow-feeling snow surfaces to identify where these wind slabs could be triggered.
Glide Avalanches: The cycle of glide avalanches has been very active throughout the season so far, but in the past week the activity seems to have slowed down significantly. Despite this encouraging trend, we always recommend identifying glide cracks and trying to minimize your time spent underneath them to avoid these potentially large and destructive avalanches.