Avalanche Forecast
Issued: Feb 9th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
dsaly,
Avalanche Canada
Outflow winds are expected to pick up and impact loose snow. Be wary of wind loaded slopes, especially where a slab builds over weak surface hoar.
Summary
Confidence
Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.
Weather Forecast
TUESDAY NIGHT - Cold and mostly clear / moderate northwest wind / alpine low temperature near -28
WEDNESDAY - Sunny / moderate increasing to strong east wind / alpine high temperature near -20
THURSDAY - Sunny / moderate to strong east wind / alpine high temperature near -18
FRIDAY - Sun with increasing cloud / moderate to strong northwest wind / alpine high temperature near -15
Avalanche Summary
On Monday, skiers were able trigger unsupported pillows failing on surface hoar down 25-40 cm near Terrace. In the north of the region, skiers found reactive wind slabs in immediate lee features in the alpine. A handful of small (size 1-1.5) natural wind slab avalanches were observed by road patrols.
On Sunday, 2 size 1 natural avalanches were reported in near Bear Pass, its likely that winds had more impact in the northern areas of the forecast region.
On Saturday, a size 2 persistent slab avalanche was intentionally triggered on a north aspect at 1200 m, failing down 35 cm on surface hoar. Skiers also reported a reactive weak layer down 35 cm producing cracking underfoot and sudden results in test profiles between 800 and 1100 m. In the far north, a handful of small (size 1.5) wind slab avalanches failed naturally.
On Friday, numerous dry loose avalanches were reported up to size 2 during the storm in steep terrain.Â
On Thursday, reports indicated several small features were reactive up to size 1 on the surface hoar that was buried in late January.Â
Snowpack Summary
Cold temperatures are encouraging surface faceting and variable winds are impacting loose snow. Increasing outflow winds will reverse load features.Â
The late January interface is down 30-70 cm, this consists of surface hoar in sheltered locations, a crust on solar features, and facets and stiff wind affected snow at upper elevations. Below treeline, 10-30 cm of snow sits above isolated pockets of surface hoar and a crust that is more prominent on solar aspects.Â
The mid-pack seems to be well settled. Deep persistent layers appear to have mostly become unreactive, with the exception of the Bear Pass area and the far reaches south of Kitimat.Â
Terrain and Travel
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Watch your sluff: it may run faster and further than you expect.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Outflow winds will redistribute loose snow building reactive slabs and reverse loading features. Avalanches will be most likely in wind loaded areas and where the snow feels stiff or punchy. Be mindful of loose-snow or sluff in steeper features. Note that winds have been higher further north in the forecast region (around Bear Pass), and avalanche hazard may be higher where winds have penetrated into lower elevations.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
30-70 cm sits above a buried weak interface that consists of surface hoar, facets, and/ or a crust. As the snow above this layer becomes more consolidated, the likelihood of avalanches may increase.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Feb 10th, 2021 4:00PM
