Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Dec 26th, 2018–Dec 28th, 2018

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 unlikely, human triggered possible.
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, human triggered possible.

Regions

Vancouver Island.

Main concerns: Wind Slab, Loose Wet, Cornice Fall.

Travel and Terrain Advice

Santa delivers a late Christmas present with some nice snow falling overnight on the 25th. But be wary...

Avoid wind loaded lee (NE-NW) alpine slopes, open lee slopes at treeline and crossloaded features during and after the storm Christmas night (Tues Dec 25).

Continue to give cornices a wide berth both after Tuesdays storm and as temps and freezing levels rise late Friday (esp if there is rainfall). 

As temps climb and if rain falls on our snowpack late Friday, avoid exposure above terrain traps (rocks, creeks, cliffs, depressions, gullies, etc) as loose wet slides tend to have significant strength, weight and power.

Avalanche Summary

New avalanche activity limited to some loose dry surface snow sloughing on steep treeline cool shaded terrain (NW-NE).

Snowpack Summary

Warm daytime temps and cool nights have begun to tighten/stabilize our multi layered snowpack.

Snowpack Details

Surface: Alpine characterized by wind effected snow. Treeline and below, there is still some nice new snow preserved on northern aspects. However, on solar aspects the surface snow is now moist and heavier. Upper: A supportive and tightening layer of recent snowfall, with the Dec 23rd storm shear gaining stability and becoming less of a concern. Mid: The Dec 22nd crust is thin and well buried at treeline and alpine elevations, but it is thicker and can still be felt in the shallower snow below treeline. Lower: Well settled.

Past Weather

0 to 8 cm of new snow fell mid Monday Dec 24th with mild temps and light winds. Cold overnight temps Monday Dec 24th into Tuesday Dec 25th (Christmas) then tightened and helped stabilize our snowpack.

Weather Forecast

A moderate storm snow event late Tuesday (Christmas) night into Wednesday morning will bring snow with heavy SE winds. A lull Thursday is then followed by a significant warm up starting late Friday with potential rain to all elevations (freezing levels above 2000 m).

Wednesday Dec 26th - 10-25 cm of new snow with the largest amount forecast for the east (Strathcona) region. Winds strong (up to 60 km/h) from the SE. Temps ranging from -1 to -5. Freezing levels near 800 to 950 m.

Thursday Dec 27th - a trace to 4 cm of new snow. Winds variable and light rising to moderate SW by days end. Temps ranging from -1 to -4. Freezing level 800 to 950 m.

Friday Dec 28th - 1 to 5 cm of new snow potentially switching to rain late in the day/overnight at all elevations (weather models in debate as to how high the rain will go and in what quantity). Winds light SW rising to moderate. Temps -2 rising sharply later on up to +2. Freezing levels 700 rising to 2400 m. Nasty!

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.

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.