Avalanche Forecast
Issued: Dec 12th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs and Loose Wet.
jminifie,
Avalanche Canada
Warm, clear weather will make travel conditions favourable for the next few days but keep in mind that the early season snowpack is shallow and deeper layers should be investigated before committing to large terrain features.
Summary
Confidence
Low
Avalanche Summary
No new avalanches were reported over the weekend though evidence of a small natural avalanche cycle was reported through the most recent storm.
Whumpfing was reported from the Mt. Washington area on Sunday in recent Mountain Information Network reports.
Keep sharing your observations by submitting a MIN report! They are especially helpful in the early season when snowpack information can be limited.
Snowpack Summary
Up to 60cm of new snow arrived with strong southerly winds between last Thursday and Sunday afternoon. With the current trend of generally mild and calm weather, the upper snowpack will continue to settle and stabilize.
Higher elevation snowpack depths range from 100-140cm. A layer exists in the lower snowpack that is comprised of a crust and weak, sugary facet crystals. Avalanche professionals in the area reported moderate Sudden Planar snowpack tests and whumpfing on this layer over the weekend. This could be something to investigate further before committing to larger pieces of terrain.
Weather Summary
Monday night
Mostly clear. Temperature -4ËšC. Winds from the north at 20km/h.
Tuesday
Partly cloudy. A low of -4ËšC and a high of +1ËšC with an inversion in the alpine. Winds from the north at 10km/h
Wednesday
Mainly clear. A low of -4ËšC and a high of +2ËšC in a warm alpine inversion. Winds from the north at 20km/h
Thursday
Mainly clear. A low of -4ËšC and a high of +2ËšC in a warm alpine inversion. Winds from the north at 15km/h
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- The likelihood of deep persistent slab avalanches will increase with each day of warm weather.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
- Avalanche hazard may have improved, but be mindful that deep instabilities are still present.
- If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
- As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
Problems
Deep Persistent Slabs
A layer involving a crust and sugary facets has been reported to exist in the lower snowpack. This layer has produced whumpfs and planar snowpack test results. With warm weather forecast for the coming days under an inversion, one should investigate this layer further and be suspicious of larger, convex terrain features.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Even though it's December, steep solar aspects could produce loose wet avalanches with warm alpine temperatures during the inversion over the next few days. Keep an eye on daytime warming and remember that loose wet avalanches can step down to deeper instabilities.
Aspects: South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 13th, 2022 4:00PM
