Avalanche Forecast
Regions: Crowsnest North, Crowsnest South.
7AM UPDATE: Winds were stronger than forecast last night.
Watch for changing conditions throughout the day. New snow is expected to bond poorly to the underlying surface.
Confidence
Moderate
Avalanche Summary
In the past few days, a few natural and human-triggered size 1 loose wet avalanches were observed from steep terrain on solar aspects.
On Saturday, avalanches up to size 2.5 were reported in the Crowsnest South area, including some deep releases. We suspect these deep persistent slabs occurred as a result of strong sun and warmer temperatures. This problem will likely reemerge throughout the spring when the snowpack undergoes rapid changes from sun, rain or warming.
If you have any observations from this data sparse region, especially regarding a potential deep persistent slab problem, let us know what you are seeing by submitting a report to the Mountain Information Network.
Snowpack Summary
Up to 15 cm of new snow may accumulate at upper elevations by end of day Friday. This new snow overlies a sun crust on solar aspects, a rain crust below 1700 m, and wind-affected snow in exposed terrain at higher elevations. Small facets and/or surface hoar may also exist in shaded and wind-sheltered terrain.
A melt-freeze crust with facets above can be found 50 to 120 cm deep. The layer is currently dormant and has not produced any recent avalanche activity in the region but professionals are still tracking it to watch for signs of it waking up.
The weak layer at the base of the snowpack produced some large avalanches with strong sun and warm temperatures earlier in the week. Activity on this layer is anticipated to taper with cooler, cloudier weather but we will continue to monitor this layer for signs of reactivity.
Weather Summary
Thursday night
Cloudy with clear periods and isolated flurries. Alpine temperatures drop to a low of -6 °C. Ridge wind 15 to 45 km/h from the southwest. Freezing level at valley bottom.
Friday
Flurries, trace to 10 cm of accumulation. Alpine temperatures reach a high of -5 °C. Ridge wind south 10-35 km/h. Freezing level rises to 1400 metres.
Saturday
Flurries, 5 to 10 cm of accumulation. Alpine temperatures reach a high of -3 °C. Ridge wind light from the west. Freezing level rises to 1600 metres.
Sunday
Cloudy with sunny periods and isolated flurries. Alpine temperatures reach a high of -7 °C. Ridge wind light from the east. Freezing level at valley bottom.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Use small low consequence slopes to test the bond of the new snow.
- Watch for signs of slab formation throughout the day.
Avalanche Problems
Wind Slabs
New snow and wind may form small but reactive wind slabs in lee areas.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2