Avalanche Forecast

Archived

Mar 19th, 2025–Mar 20th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

North Columbia, South Columbia, Esplanade, Jordan, North Selkirk, Dogtooth, Badshot-Battle, Central Selkirk, Goat, Gold.

Human-triggered avalanches are likely.

Choose conservative terrain and regroup in safe spots.

Confidence

Moderate

Avalanche Summary

On Tuesday five very large (size 3) natural avalanches were reported, two were triggered by cornice failures. Numerous large (size 2) natural and human-triggered avalanches were also reported. On Monday, several size 2 and one size 3 natural avalanches were reported. There were also four size 2 remotely-triggered avalanches, two by riders and two by a snowcat.

Large human-triggered avalanches continue to remain likely.

Snowpack Summary

Up to 25 cm of new snow has fallen since Monday. A sun crust and/or moist snow can be found on slopes exposed to the sun.

Three persistent weak layers consisting of surface hoar and/or facets are found in the middle of the snowpack. The early March layer is between 60 and 120 cm down. The mid-February layer is between 70 and 150 cm deep and a layer from late January is down 150 cm. In lower elevations, these layers sit over a crust.

Below this, the snowpack is well settled.

Weather Summary

Wednesday night

Cloudy with 0 to 5 cm of snow. 30 to 50 km/h south ridgetop wind. Treeline temperature -6 °C.

Thursday

Cloudy with 5 to 10 cm of snow. 20 to 30 km/h southwest ridgetop wind. Treeline temperature -5 °C.

Friday

Cloudy with 5 to 15 cm of snow. 30 to 50 km/h southwest ridgetop winds. Treeline temperature -5 °C.

Saturday

Moslty cloudy with 0 to 5 cm of snow. 20 to 30 km/h west ridgetop winds. Treeline temperature -5 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.

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.

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.