Avalanche Forecast
Issued: Mar 3rd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Wind Slabs and Persistent Slabs.
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Avalanche Canada
Warm temperatures and sunshine will elevate avalanche conditions, especially on south-facing slopes. Stick to low angle shaded terrain.
Summary
Confidence
Weather Forecast
A ridge of high pressure brings dry, warm, and sunny weather.
WEDNESDAY NIGHT: Clear skies, light south wind, treeline temperatures drop to -3 C.
THURSDAY: Sunny, light south wind, freezing level climbs to 2100 m with treeline temperatures around +1 C.
FRIDAY: Mix of sun and cloud, moderate south wind, freezing level climbs to 1800 m with treeline temperatures around -1 C.
SATURDAY: Cloudy with scattered flurries and 5-10 cm of new snow, light southwest wind, freezing level climbs to 1500 m with treeline temperatures around -3 C.
Avalanche Summary
On Thursday the primary concern is natural avalanches on steep sun-exposed slopes. These will most likely present as wet loose avalanches, but larger wind and persistent slab avalanches are also possible. Read the latest Forecaster Blog for concerns about the warming.
Since the weekend, avalanche activity has primarily been limited to small (size 1) wind slab and dry loose avalanches on a variety of aspects. There have been a few reports of sporadic persistent slab avalanches in the past month failing on the late January persistent weak layer. While this layer is trending towards being unreactive, the current warming trend could temporarily heighten the likelihood of avalanches on this layer.
Snowpack Summary
Rising freezing levels and sunshine will be melting, and potentially destabilizing, snow surfaces the next few days. Higher elevations have been impacted by recent wind from the southwest, likely leaving wind slabs lurking on shaded north and east slopes.
The lower snowpack has been strengthening with reactivity on persistent weak layers on the decline. The two layers of concern have been a layer of facets that was buried in mid-February (60-100 cm deep) and a layer of surface hoar and/or crusts that was buried in late January (80-120 cm deep). The impulse of warming over the next few days will likely be the final test on these layers, as there is some uncertainty about whether they will become reactive with warming temperatures.
Terrain and Travel
- Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
- Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
- The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
- Expect slab conditions to change drastically as you move into wind exposed terrain.
Problems
Loose Wet
Wet loose avalanches are likely to release naturally on steep sun-exposed slopes.
Aspects: South East, South, South West.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Reactive wind slabs likely exist in steep open terrain at alpine and treeline elevations, especially on north and east aspects.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Warming temperatures could temporarily increase the likelihood of large persistent slab avalanches. There are two potential layers of concern buried 60-120 cm deep across the region that have produced some sporadic activity over the past weeks.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 4th, 2021 4:00PM
