Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Very Likely
- Size
- 2–3
If you were Santa deciding whether this season's snowpack was naughty or nice, you'd have an easy answer. Lurking beneath a charming (and powdery) exterior is a dangerous character flaw—weak October snow buried beneath a dense 2-3+' slab. The facet layer is most prevalent on mid and upper elevation shady slopes (NW-N-NE-E facing).
Our snowpack's true nature has been revealed a number of times this winter, including yesterday. Partial clearing skies revealed numerous large to very large avalanches that released as a result of Thursday's storm. Perhaps most notable is a huge avalanche on Galena Peak (photo above/right) that would have destroyed your truck, the garage it was parked in, and the neighborhood you live in. Other large avalanches occurred in the Smokys (photo, photo) and Sawtooths (photo, photo). Observers on Titus Ridge watched a slope below them crack as they skied along the low angle ridge. Continued loading due to wind last night and snowfall today will keep our dangerous snowpack on the brink.
While the snowpack deserves a few lumps of coal, you deserve some powder skiing and riding. Luckily for all of us that have been good boys and girls this year, there is incredible powder conditions to be enojyed in low angle terrain. Sticking to gentler slopes is the primary way to avoid the persistent slab, but also avoid being below steeper terrain since the possibility of remote triggering is real.
(12/24/2021) This very large natural avalanche released in the NW bowl of Galena Peak as a result of Thursday's storm. It broke over 1000' wide and failed on weak October snow low in the snowpack.