Storm Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
Recent avalanches: Observers near Seward saw evidence of a natural avalanche cycle in the wake of Tuesday's storm on the peaks surrounding Seward. Additional natural avalanches were observed on Sunday, Feb. 1 northwest of Lost Lake that were small to large in size and likely occurred on Thursday, January 29.
Another storm today will bring a wave of rain, strong winds from the east, and 6 to 12" of snow falling above ~2,000' on a variety of surfaces. Temperatures today are expected to cool only slightly, with another 0.6 to 0.8" of rain falling below ~2,000'. Wet, storm slab activity is likely to continue today where the snowpack is seeing rain. Pay particular attention to unsupported, convex slopes in the mid-elevation bands (think steep, rolly terrain adjacent to Lost Lake) where the additional water weight will be stressing an already wet snowpack. Even a small avalanche today will be quite heavy and difficult to escape, given how dense and saturated the storm slab is. Keep terrain choices conservative, and consider the consequences (i.e., terrain traps) if a slope does slide.
In areas above the rain/ snow line, strong winds from the east and new snow will be building fresh wind slabs and storm slabs 1-2' deep. These will be deposited on a variety of surfaces, including a recently formed rain crust that may extend as high as 3,000' in the Seward zone. Triggering a smaller storm slab today still has the potential to affect the deeper layer of facets that could produce a very large avalanche in connected terrain.
Wet loose: We saw some evidence of wet loose avalanches in steep terrain, below ~2,500'. These are likely to be small, but could still prove troublesome in consequential terrain.
Photo: Mik Dalpes
Natural storm slab debris is seen on the north side of Bear Mountain, near Seward in the wake of Tuesday's warm, wet weather.
