Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely
- Size
- 3
The Dry January Layer (DJL) of faceted snow is 2-4 feet deep and buried by a strong slab and supportable crusts, with the last reported human-triggered avalanche failing on the DJL was nearly two weeks ago. An outlier large natural avalanche, however, ran at the end of the storm on March 6th in Stairs Gulch, extreme terrain in mid-Big Cottonwood Canyon.
The bulk of the avalanche failing on the PWL occurred during the mid-February avalanche cycle, with two outliers releasing at the end of the last storm.
We now view the PWL as dormant and human triggered avalanches are unlikely but not impossible. If you're looking for trouble, however, you may find it in recently wind loaded, steep, thin, rocky terrain in the highest elevations on the north side of the compass; you know, extreme terrain like Stairs Gulch, Lone Peak, the Coalpit Headwall, Airplane Peak; etc.
Looking ahead: with the skyrocketing temperatures next week, we anticipate the PWL becoming active again as melt water percolates down to the faceted grains and wet slab avalanches become our central avalanche problem. Stay tuned.