Avalanche Forecast
Regions: Glacier.
Rising freezing level Thursday may weaken cornices and cause them to fail.
Watch for this overhead hazard and plan to travel early on exposed slopes.
Weather Forecast
This week a ridge of high pressure brings dry days, some valley cloud and seasonal temperatures.
Tonight: Cloudy with clear periods, Alp low -8*C, light NW winds
Thurs: Sun and cloud, Alp high -2*C, light SW ridgetop winds, fz lvl:1300m
Fri: Sun and cloud, Alp high -3*C, mod SW winds, fz lvl:1100 m
Sat: Sun and cloud, Alp high -4*C, mod SW winds
Snowpack Summary
Surface hoar rowing on surface, 5-8mm BTL, 2-4mm TL and above. Variable breakable surface crust exists on S-W aspects. Wind-affect can be found at treeline and above. The Jan 20 (2-4mm) surface hoar down 35cm, and Jan 11 (2-5mm) surface hoar down 70-90cm. The Dec 1 crust/facet combo is down ~1.5 - 2.5m and will require a big trigger to come alive.
Avalanche Summary
Observations from Jan 25th:
No new avalanches observed in the highway corridor nor in the Sir Donald/Avalanche Crest area.
A backcountry report of a natural cornice fall in the loop brook drainage triggering a size 3.0 avalanche.
A field team in the Sir D/Avalanche Crest zone ski-cut small features to 40* with no results.
Confidence
The weather pattern is stable
Avalanche Problems
Wind Slabs
Wind slabs can be found in the Alpine and at Treeline. Watch for these firm deposits of snow on lee features. The Jan 20th surface hoar is present beneath these slabs.
- Convex features and steep unsupported slopes will be most prone to triggering.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2
Persistent Slabs
Several persistent weak layers (see snowpack summary) are present in the upper 1m. Test the strength of these layers before committing to your line.
- Be wary of slopes that did not previously avalanche
- If triggered the persistent slabs may step down to deeper layers resulting in very large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2.5
