Avalanche Forecast
Issued: Dec 29th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
bchristie,
Avalanche Canada
Avoid wind exposed slopes at treeline and above, and you'll likely find cold, blower pow. Wind slabs are the main avalanche concern, but consider that ANY problem could get amplified into an emergency on these cold, short days.
Summary
Confidence
Moderate - Uncertainties in both the snowpack structure and the weather forecast limit our confidence.
Weather Forecast
Cold arctic air will persist until Sunday, when we are back into a warmer, wetter, westerly weather pattern.Â
WEDNESDAY NIGHT: Overcast. 5-15 cm of snow expected. Strong west winds trending to northwest at higher elevations. Treeline low around -11 C.
THURSDAY: Overcast. 0-5 cm of snow expected. Moderate to strong northwest wind. Treeline temperatures around -8 C.
FRIDAY: A mix of sun and cloud. Possible trace of snow expected. Light to moderate northwest wind, treeline temperatures around -10 C.
SATURDAY: Overcast. 2-10 cm of snow expected. Strong southwest wind. Freezing levels rising to 500m
Avalanche Summary
No new avalanches were reported on Tuesday and Wednesday.
Over the past few days there have been some reports of small (size 1) loose dry avalanches (sluffs) and some small isolated wind slab avalanches.Â
Snowpack Summary
With plenty of soft, light snow available for transport, expect wind slab formation if wind speed picks up. A northwesterly wind direction means atypical cross-loading and reverse loading patterns.Â
30-50 cm now sits over a freezing rain crust below 1500 m and above this elevation it may rest on a layer of large surface hoar crystals. Our field team reported easy shears on this layer in their MIN report last week.Â
The lower snowpack is generally well bonded.
Terrain and Travel
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- Recent new snow may be hiding windslabs that were easily visible before the snow fell.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Wind Slabs
With plenty of soft, light snow available for wind transport, we expect to see wind slab formation in the alpine and open areas near treeline. A north or northwest wind means atypical cross-loading and reverse loading patterns. Be especially cautious near ridgetops.
Aspects: North East, East, South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 30th, 2021 4:00PM
