Avalanche Forecast
Regions: McGregor, North Rockies, Pine Pass.
Make conservative terrain choices and give the storm snow time to heal. There is some uncertainty in the intensity of Saturday's weather and how the snowpack will handle it.
Confidence
Low
Avalanche Summary
No new avalanches were reported in the past few days in the region but observations are limited.
If you are out in the backcountry please consider filling out a Mountain Information Network report.
Snowpack Summary
As a cold front passes over the region new snow will add to the storm slab problem. At lower elevations, a rain crust exists down 30cm, with reported elevations extending up roughly 1200 m.
Snowpack depths are shallower than normal, and several buried weak layers have been a concern over the past few weeks. One is a recently buried surface hoar layer found up to 60cm deep in sheltered terrain features at treeline and above. At this same depth, a crust exists on steep south facing slopes. Another layer of facets, crust, and surface hoar was buried around Christmas and is now up to 80cm cm deep. Finally, a layer of large, weak facets buried in November is found near the bottom of the snowpack. This layer is likely most problematic in alpine terrain, where shallower avalanches could scrub down to these basal facets.
Recent observations suggest the buried weak layers are gaining strength, but not enough to trust them in high consequence terrain.
Weather Summary
Friday Night
Stormy with 5 to 10cm of new snow expected. Strong southwest winds and a low of -3 at 1500m.
Saturday
Stormy with up to 15cm of new snow. Strong southwest winds shifting to moderate northwest and a high of -3 at 1500m.
Sunday
A mix of sun and cloud with light flurries bringing trace amounts of new snow. Moderate westerly winds and a high of -6 at 1500m.
Monday
Stormy with up to 15cm of new snow expected. Strong northwest winds and a high of -3 at 1500m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Dial back your terrain choices if you are seeing more than 20 cm of new snow.
- Be carefull around freshly wind loaded features.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Avalanche Problems
Storm Slabs
Rider triggerable storm slabs could increase in size and sensitivity throughout the day.
Be aware that storm slab avalanches could step down to deeper layers resulting in a larger and more destructive avalanche.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 2
Persistent Slabs
Several buried weak layers remain a concern for human triggering. At treeline elevations, the main concern is surface hoar and crust layers in the middle of the snowpack, especially on steep convex openings. In the alpine, the main concern is weak facets at the bottom of the snowpack, especially on rocky slopes with variable snow depths.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 2.5