Avalanche Forecast

Archived

Mar 1st, 2024–Mar 2nd, 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

North Columbia, South Columbia, Esplanade, Jordan, North Selkirk, West Purcell, Badshot-Battle, Central Selkirk, Goat, Gold, Retallack, Whatshan.

Persistent slabs continue to be primed for rider triggering even though natural avalanche activity has tapered off. Stick to low consequence terrain.

Confidence

Moderate

Avalanche Summary

Numerous large to very large natural and human triggered persistent slab avalanches continue to be reported through the latter part of the week. Many of the human triggered avalanches have been reported as remotely triggered (from a distance). This speaks to the sensitivity of the persistent slab.

Expect persistent slab avalanche activity to continue.

Snowpack Summary

70 to 110 cm of recent snow sits on a variety of layers, including surface hoar in wind-sheltered terrain, weak facets, or a hard melt-freeze crust on sun-exposed south and west-facing slopes. Gusty southerly winds have stripped fresh snow in exposed areas and loaded lee features with over 130 cm of wind-blown snow.

A thick and hard widespread crust that formed in early February is buried 60 to 120 cm deep and is found up to around 2400 m. This crust may have a layer of facets above it and is a troublesome avalanche layer.

The remainder of the snowpack is settled.

Weather Summary

Friday Night

Mostly cloudy isolated flurries. 20 to 40 km/h southeast ridgetop wind. Treeline temperature -8 °C. Freezing level at valley bottom.

Saturday

Mostly cloudy with sunny breaks. 15 to 30 km/h southeast ridgetop wind. Treeline temperature -4 °C. Freezing level 1000 m.

Sunday

Mostly cloudy with scattered flurries, 3-5 of snow. 15 to 30 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level valley bottom.

Monday

Mix of sun and cloud. 10 to 20 km/h southeast ridgetop wind. Treeline temperature -5 °C. Freezing level at valley bottom.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Only the most simple non-avalanche terrain free of overhead hazard is appropriate at this time.
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.

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.