Avalanche Forecast

Archived

Dec 24th, 2025–Dec 25th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Sea To Sky, Brandywine, Garibaldi, Homathko, Spearhead, Tantalus.

Sunshine doesn't mean stability! Santa brought a week of fresh snow that still needs time to settle.

A gift from me to you: the best and safest riding is in sheltered terrain 🎄🎁

Confidence

High

We have a good understanding of the snowpack structure and confidence in the weather forecast

Avalanche Summary

Last Sunday, a snowcat in the Whistler area triggered a size 2 persistent slab on a northwest aspect in the alpine.

On Tuesday, near Whistler, skiers and explosives were able to trigger size 1 to 2 storm slabs in the alpine and treeline. One notable result stepped down to the mid-December crust.

Looking forward to Thursday, the recent storm snow still needs time to stabilize. Wind-loaded terrain at upper elevations will be the prime suspect for human-triggered avalanches.

Snowpack Summary

20 to 30 cm of recent storm snow overlies roughly 150 cm of new snow in the past week. Strong southerly wind has left a variety of surfaces - wind slabs and loaded pockets in lee features, scoured rock in open terrain, and storm slabs and softer snow in sheltered areas.

This week's storm snow buries a melt-freeze crust that exists at 2200 m and below. The depth of this crust is highly variable due to extensive recent wind transport.

A crust with facets, formed in mid-November, is buried an estimated 80 to 150 cm deep. With limited observations, especially in the alpine (which did not have the same mid-pack crust development), we're not ready to rule out this layer of concern quite yet.

Weather Summary

Wednesday Night
Mostly cloudy. 3 to 4 cm of snow. 10 km/h southwest ridgetop wind. Treeline temperature -5 °C.

Thursday
Mostly sunny. 10 km/h southeast ridgetop wind. Treeline temperature -3 °C.

Friday
Mostly cloudy. 2 to 10 cm of snow. 10 km/h west ridgetop wind. Treeline temperature -6 °C.

Saturday
Mostly sunny. 1 cm of snow. 10 km/h northwest ridgetop wind. Treeline temperature -11 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
Don't let the desire for deep powder pull you into high consequence terrain.
Be especially cautious as you transition into wind-affected terrain.
Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Problems

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.

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.