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

Feb 11th, 2022–Feb 12th, 2022

Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.

Regions

Northwest Inland.

Dynamic weather requires dynamic decision making. Current snowpack conditions vary with elevation, and could change through the day with above zero temperatures and sunshine. Keep a constant watch for signs of instability and prepare for challenging travel.

Confidence

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

Weather Forecast

Freezing levels will vary greatly across the region. Expect as high as 2000 m around smithers, lower as you look further north, and as low as 500 m around Ningunsaw.

FRIDAY NIGHT: Mostly clear in Smithers and south, mostly cloudy north of Smithers. 0-2 cm of snow expected. Moderate to strong west wind. Possible above freezing layer making for temperatures above 0 °C between 1200 and 2200 m in the southern end of the region. 

SATURDAY: Mostly clear in Smithers and south, mostly cloudy north of Smithers. 0-2 cm of snow expected. Strong west wind. Possible above freezing layer making for temperatures above 0 °C between 1200 and 2200 m in the southern end of the region. 

SUNDAY: Mostly cloudy. 0-2 cm of snow expected. Light southwest wind. Above freezing layer breaking down, freezing levels around 750 m. 

MONDAY: Partly cloudy. Possible trace of snow expected. Moderate northwest wind. Freezing levels at valley bottom in the morning, rising as high as 1000 m in the south of the region. 

Avalanche Summary

No new avalanches were reported on Friday before 4 pm.

On Wednesday, a warm, wet, windy storm produced a natural avalanche cycle, with numerous large avalanches reported (up to size 3.5). During the height of the storm, most avalanches were reported as loose wet, wet slabs, and glide slabs. In areas where the freezing level was lower (in the north of the region), some avalanches started as wind slabs or cornice falls, and became loose wet as they ran to lower elevations. As the temperature cooled overnight, avalanche activity continued, with large, natural, wind slab and cornice triggered avalanches occuring through until Thursday morning. 

Snowpack Summary

Below 2000 m (1000 m in the north end of the region), 10-30 mm of rain fell throughout the day on Wednesday, soaking the upper snowpack. In most places, a firm crust has formed on the surface. At treeline, this crust may be supportive to skis and snowshoes, but breakable under a snowmobile or a boot. Below treeline, the crust is thinner, weaker, and overlies moist snow.

Above 2000 m in the southern end of the region there are areas that received up to 30cm of snow, but observations so far suggest that this terrain was hammered by the wind, scouring some terrain and forming unreactive wind effected surfaces elsewhere.

See here for a summary of the conditions on Thursday in the Microwave area from our field team.

In the northern end of the region, where there was still dry snow available for transport, Thursday's wind formed reactive windslabs and cornices in the alpine. 

In some areas a combination of two thin crusts with faceting above and below exists 40 to 50 cm deep. Deeper in the snowpack, two weak layers may exist around 60 to 120 cm deep. The first is a surface hoar layer from mid-January and the second is a layer of faceted snow from early January. These layers haven't produced recent avalanches, but they are producing concerning results in snowpack tests, and the potential remains until these layers bond to the snowpack.

Terrain and Travel

  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • A crust on the surface will help bind the snow together, but may make for tough travel conditions.
  • Be alert to conditions that change with elevation and sun exposure.
  • Although their spatial distribution is isolated, wind slabs are reactive.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.

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.