Avalanche Forecast

Moderate - The snowpack structure is generally well understood. Uncertainty is due to the fact that deep persistent slabs are particularly difficult to forecast.

Sunday Night: Mostly clear. No new snow expected. Moderate northwest wind trending to strong at higher elevations. Above freezing layer breaking down. Freezing level dropping to near valley bottom, alpine low around -3 C. 

Monday: Mix of sun and cloud. No new snow expected. Moderate northwest wind trending to strong at higher elevations, but tapering off over the day. Alpine low around -5 and freezing levels rise to around 1250 m late in the day. 

Tuesday: Mostly sunny. No new snow expected. Light southwest wind trending to moderate northwest at higher elevations. Freezing levels at valley bottom overnight, and rising to 750 m through the day. 

Wednesday: Partly cloudy. No new snow expected. Moderate northwest wind trending to extreme at higher elevations. Freezing levels at valley bottom overnight, and rising to 750 m through the day. 

On Saturday, there were several reports of snowballing/pinwheeling/point-releases, a few small cornice failures, and small, loose-wet avalanches on steep solar aspects. 

On Friday, several natural wind slab avalanches were reported in Kootenay Pass. They were mostly on northeast aspects at treeline. 

On Thursday, numerous storm slab avalanches were reported up to size 2. 

During the warm previous storm, mid-last week, a large widespread avalanche cycle occurred with most avalanches releasing within the storm snow and some on Jan 11 surface hoar layer. Strong solar radiation and warm temperatures were also at play after the storm, producing numerous avalanches at all elevations and scouring avalanche paths to the ground in places.

There are reports of a new surface crust on steep solar aspects from the warm temperatures and sun on Saturday, and surface hoar growing in sheltered areas.

10-20 cm of recent snow combined with strong winds formed wind slabs and buried a series of recent surface hoar layers and melt-freeze crusts found down 15 cm and another down 25 cm. These extend to 2400 m and are most prevalent (thicker) on southerly aspects. 

Digging deeper, down 50-60 cm is yet another surface hoar layer that has seen recent avalanche activity. A well-consolidated mid-pack exists below this and above the early December crust/facet interface. 

The early December crust/facet layer has been responsible for sporadic but very large, persistent slab avalanches over the past month. The crust is now buried 120-200 cm deep except in thin, wind-affected areas near ridgetops. Daytime warming, sun, cornice fall, and smaller avalanches through the forecast period may be enough to wake this layer up and initiate large to very large avalanches.

• In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
• If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
• Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
• Avoid terrain traps where the consequence of any avalanche could be serious.
• A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.