Avalanche Forecast
Issued: Mar 25th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
zryan,
Avalanche Canada
Wind slabs may be reactive to human triggering at upper elevations. Use caution in lee and cross-loaded terrain near ridge crests.
Summary
Confidence
Weather Forecast
FRIDAY NIGHT: Mainly cloudy. 15 to 35 km/h southwest wind, alpine temperature -3 C. Freezing level dropping to 1000m
SATURDAY: Cloudy with light precipitation, 15-40 km/h southwest winds, alpine temperature rising to -2 C. Freezing level reaching 2000 m.
SUNDAY: Cloudy with precipitation, 5 cm of new snow accumulation at higher elevations. 20-50 km/h southwest winds, alpine temperature rising to 0 C. Freezing level reaching 2600 m.
MONDAY: Cloudy with snowfall, 5-10 cm accumulation. 15-30 km/h northwest winds, alpine temperature rising to -3 C. Freezing level reaching 2000 m.
Avalanche Summary
Widespread wet loose and wet slab avalanche activity was observed on Wednesday during the warm spell. Several large (size 2-3) cornice failures were also observed.
Several large (size 2-3) persistent slab avalanches occurred during the warm-up on Wednesday and Thursday. These slabs were 70 to 150 cm deep, on all aspects from 2100-2300 m. Looking forward, riders may still be able to trigger this layer in isolated areas.
Snowpack Summary
5 to 15 cm of recent snow may have formed small wind slabs in lee terrain features in the alpine from southwest wind. Below 2300 m and to the mountain top on solar aspects, a melt-freeze crust exists, with moist snow below.
A weak layer may be found around 50 to 100 cm deep. The layer consists of surface hoar crystals in treeline terrain on northerly aspects or weak faceted grains above a hard melt-freeze crust on sun-exposed slopes (i.e., east, south, west). It has been reactive between 1800 and 2300 m but given the recent rain, it is most likely to be triggered between 2000 and 2300 m. It should still be treated as suspect if you find it in your riding area.
The remainder of the snowpack is well-bonded.
Terrain and Travel
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Carefully evaluate steep lines for wind slabs.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Wind slabs may exist in steep, lee terrain features in the high alpine.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Persistent Slabs
A weak layer may be found around 50 to 100 cm deep. The layer is most likely to be triggered between 2000 and 2300 m, on all aspects. The likelihood of triggering this layer is decreasing, but the consequence of doing so would be high.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 26th, 2022 4:00PM
