Avalanche Forecast

Archived

Mar 1st, 2022–Mar 2nd, 2022

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 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, human triggered possible.

Regions

South Coast.

Reactive storm slabs continue to build at higher elevations and thicker slabs will likely exist on leeward slopes due to wind redistributed storm snow. At lower elevations, loose wet avalanches are likely as rain soaks the snowpack.

Confidence

Moderate - Forecast precipitation (either snow or rain) amounts are uncertain.

Weather Forecast

Strong southwesterly winds result in an onshore flow of a cool, and unstable air mass. This brings moderate to heavy snow at upper elevations for the Vancouver Island ranges and the Coast Mountains.

Tuesday Night: 10-15 mm of precipitation expected with strong southwest winds. Freezing levels 1400 m.

Wednesday: Another 10 mm of precipitation falling as snow above 1300 m. Strong southwest wind continues.

Thursday: Drying and cooling trend with the freezing level dropping to 900 m with light northwest winds at ridgetop and clearing skies.

Avalanche Summary

On Monday, several storm slabs were reported up to size 2. This followed a widespread natural storm slab avalanche cycle on Sunday. Skier-controlled storm slabs were triggering remotely and propagating widely at treeline and below as shown in this MIN report. Natural avalanche activity will likely continue through Wednesday with reactive storm slabs in the alpine and upper treeline and loose wet avalanches below treeline.

Snowpack Summary

30-60 cm of new snow from yesterday is becoming soaked by rain. Above 1400 m, snow may begin to accumulate over the rain soaked surface as the freezing level sinks back down. The new snow sits over a variety of weak surfaces including facets, surface hoar and sun crust, to which it appeared to be bonding poorly yesterday.

50-80 cm below the surface, a 30cm thick crust caps the underlying snowpack which is well settled and strong.

Terrain and Travel

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
Watch for fresh storm slabs building throughout the day.
The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
Keep in mind that wet avalanches can be destructive due to their high density.

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.

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.