Avalanche Forecast
Issued: Apr 2nd, 2021 4:00PM
The alpine rating is Wind Slabs and Cornices.
, the treeline rating is , and the below treeline rating is Known problems includeHigh elevation north aspects hold the best snow but are also the most likely place to encounter wind slabs. Be ready to back off slopes as warm temperatures moisten and weaken the upper snowpack. Check out our latest blog post on managing these not-quite-yet-spring conditions.
Summary
Confidence
High -
Weather Forecast
Friday night: Mainly cloudy with continuing isolated flurries. Light to moderate southwest wind. Alpine high temperatures around -6. Freezing level valley bottom.
Saturday: Cloudy with continuing isolated flurries, increasing overnight. Moderate to strong south winds. Alpine high temperatures around -4. Freezing levels to 1800 m.
Sunday: 10-15 cm new snow overnight then clearing. Light southwest wind shifting northwest over the day. Alpine high temperatures around -5. Freezing level 1500 m.
Monday: Sunny. Light to moderate northwest wind. Alpine high temperatures around -2. Freezing level 1800 m.
Avalanche Summary
No reports of avalanche activity since Wednesday when small (size 1) natural and skier triggered loose wet avalanches were observed on south aspects, running on a recent crust layer. One recent natural size 2 cornice failure was also noted.
On Tuesday, a skier triggered size 2.5 involvement was reported in neighboring Glacier National Park resulted in lost gear and minor injuries. The avalanche is suspected to have run on a buried crust in the upper snowpack.
Snowpack Summary
Light accumulations of new snow have added to wind affected surfaces in alpine areas and to settled dry snow on more sheltered, shaded aspects above 2000 metres. Below this elevation and on solar aspects it dusts crusty surfaces. Below about 1500 metres, surface conditions of the diminishing snowpack will vary according to alternating light rain, wet flurries, and overnight refreezes.
At alpine and treeline elevations, a widespread crust exists (except on north-facing slopes above 1800 m) buried 50-100 cm deep. Overall the snow seems to be bonding well at this interface, although there have been a few isolated avalanches running on deeper crust layers over the past few weeks.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Extra caution is needed around cornices under the current conditions.
- A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
Problems
Wind Slabs
Recently formed wind slabs may remain reactive to human triggering in wind loaded terrain features at upper elevations.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices become weak with daytime warming. Cornice falls are dangerous in their own right and they can also trigger slabs on slopes below.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 3rd, 2021 4:00PM