Regions
Northwest Inland.
Confidence
Poor - Due to the number of field observations
Weather Forecast
A strong ridge of high pressure continues to dominate with no sign of a breakdown in sight. A nasty Above Freezing Layer of air will plague the region for most of the forecast period.Monday: Freezing Level: Valley Bottom. Precip: Nil; Wind: Mod SWTuesday: Freezing Level: Inversion, Above Freezing Air from 1200 – 2700m; Precip: Nil; Wind: Lht, SW.Wednesday: Freezing Level: Inversion, Above Freezing Air from 1200 – 2700m; Precip: Nil; Wind: Lht, SW.
Avalanche Summary
No new avalanche activity reported on Saturday. The last significant cycle tapered off Jan 15th. It featured natural avalanches to size 3.5 with releases on all aspects and elevations.
Snowpack Summary
Previously strong winds have left widespread wind loading/wind damaged snow in their wake. Most of these wind slabs are probably growing old and tired but may still pose a problem in bigger terrain. Warming temps along with a bit of rain at lower elevations has formed a variety of crusts at and below treeline. The early January surface hoar is most active in the region at treeline. It was a player during the last cycle even in low angled terrain. Look for it in the upper 50 cm of the snowpack. Professionals continue to keep an eye on the basal facets which can be found down near the ground.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.