Avalanche Forecast

Archived

Mar 2nd, 2024–Mar 3rd, 2024

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

Esplanade, North Selkirk, West Purcell, Badshot-Battle, Central Selkirk, Goat, Retallack.

Continue to choose conservative, low consequence terrain and beware of overhead and adjacent slopes. Remote triggering is a concern.

Solar input could weaken this already scary snowpack.

Confidence

Moderate

Avalanche Summary

Numerous large to very large natural and human triggered persistent slab avalanches continue to be reported throughout the region. Some have run full path to valley bottoms. Many of the human triggered avalanches have been reported as remotely triggered (from a distance). This speaks to the sensitivity of the persistent slab.

As natural avalanche activity tapers, the snowpack will remain primed for rider-triggered avalanches.

Snowpack Summary

A variety of surfaces can be found including a new crust on sun exposed terrain and wind effect in the alpine.

50 to 120 cm overlies a layer of surface hoar in wind-sheltered terrain, weak facets, or a hard melt-freeze crust on south and west-facing slopes.

A thick and hard widespread crust that formed in early February is buried about 70 to 150 cm deep and extends up to 2400 m. This crust may have a layer of facets above it. The snowpack below this crust is generally not concerning except in shallow alpine terrain.

Weather Summary

Saturday Night

Mostly cloudy with 5 to 10 cm of new snow. 15 to 30 km/h southeast alpine wind switching to southwest. Treeline temperature -11°C.

Sunday

A mix of sun and cloud with 5 cm of new snow. 5 to 25 km/h south alpine wind. Treeline temperature -9°C.

Monday

Mostly cloudy with 5 to 10 cm of new snow. 10 to 25 km/h southwest alpine wind. Treeline temperature -8°C.

Tuesday

Mostly cloudy with trace amounts of new snow. 5 to 20 km/h northwest alpine wind. Treeline temperature -14°C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Conservative terrain selection is critical, choose only well supported, low consequence lines.
Remote triggering is a concern, watch out for adjacent and overhead slopes.
Be aware of the potential for surprisingly large avalanches due to deeply buried weak layers.
Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Avoid exposure to steep sun exposed slopes.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.