Avalanche Forecast

Archived

Feb 20th, 2025–Feb 21st, 2025

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Vancouver Island, East Island, North Island, South Island, West Island.

Heavy precipitation and warming temperatures are expected to result in dangerous avalanche conditions on Friday. Travel in avalanche terrain is not recommended.

Confidence

Moderate

Avalanche Summary

On Thursday, the field team observed small wind slab avalanches. On Wednesday, a skier triggered a small wind slab on a north aspect.

Widespread natural avalanche activity should be expected heading into the weekend as the series of storms brings periods of heavy snowfall and rain.

Snowpack Summary

At higher elevations, new storm snow falls on old wind-affected snow, facets, surface hoar, and/or a melt-freeze crust. The bond of the new snow to the underlying layers is unknown. In exposed terrain, the wind has redistributed the storm snow into fresh wind slabs in leeward terrain.

A widespread crust, sometimes accompanied by a thin layer of weak facets, was buried 30-70 cm beneath predominantly low-density snow before the storm.

The mid and lower snowpack contains no other layers of concern.

Weather Summary

Thursday Night

Cloudy with 10 to 30 mm of mixed precipitation. 50 to 70 km/h southwest ridgetop wind. Freezing level 1400 m.

Friday

Cloudy with 20 to 40 mm of mixed precipitation. 70 to 90 km/h southwest ridgetop wind. Freezing level 1200-1700 m.

Saturday

Cloudy with 20 to 60 mm of mixed precipitation. 70 to 100 km/h southwest ridgetop wind. Freezing level 1400-2000 m.

Sunday

Cloudy with 20 to 40 mm of mixed precipitation. 50 to 80 km/h southwest ridgetop wind. Freezing level 1300-1800 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.
A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
Be aware of the potential for large avalanches due to buried weak layers.

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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.