Regions
Northwest Inland.
Danger may be moderate, but keep the lurking deep persistent slab problem in the back of your mind. Avoid shallow and variable snowpack areas and slopes prone to large triggers like cornices.
Weather Forecast
WEDNESDAY: Cloudy with flurries and sunny breaks. The freezing level gradually climbs to 1200 m. Ridge winds are light increasing to strong from the SE. THURSDAY: Periods of snow -10-15 cm. The freezing level is near 1500 m and winds are moderate from the E-SE. FRIDAY: A mix of sun and cloud. The freezing level is around 1200-1400 m and winds ease to light.
Avalanche Summary
A couple natural size 2 wind slabs were observed on immediate lee alpine slopes on Monday. One size 3 natural storm slab was observed in the Southwest corner of the region on Sunday. This slide probably occurred 1-2 days earlier. It released on a northeast aspect in the alpine. There were a handful of large persistent slab avalanches triggered on basal facets in the mountains north of Kispiox last week.
Snowpack Summary
Roughly 15-30 cm of snow has fallen in the past week, with the highest accumulations occurring in the southwest of the region. Strong to extreme ridgetop winds have shifted the new snow into hard or soft wind slabs in exposed terrain, adding to an ongoing wind slab problem. A layer of surface hoar from early January can be found in isolated locations between 60 and 140 cm down. There hasn't been any activity reported on this layer for a couple of weeks now and it is becoming less of a concern. In shallower areas the snowpack sits on a weak base layer of facetted snow. Recently, this layer has been active in the north of the region, responsible for several large avalanches in unsupported alpine terrain.
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.