Avalanche Forecast
Regions:
Wind slabs may remain reactive to human triggers on lee aspects in the alpine.
Avoid steep, rocky, and wind affected areas where triggering slabs are more likely.
Confidence
Moderate
Avalanche Summary
No new avalanches were reported on Thursday. However, observations are currently very limited in this region.
Observations are limited at this time of year, please consider sharing any information or photos you have on the Mountain Information Network to help guide our forecasts.
Snowpack Summary
35-45 cm of snow last week and south winds formed wind slabs on lee aspects at upper elevations.
The new snow sits over previously wind-affected snow on north and east-facing slopes and a crust on south-facing slopes.
A weak layer of surface hoar/crust/facets buried in early January is now buried well over 1 m deep. This layer has produced recent avalanche activity in the White Pass region and remains a concern in terrain where the snowpack is thin. The lower snowpack consists of basal facets, particularly in shallow areas.
Weather Summary
Friday Night
Mostly cloudy / 30 km/h east ridgetop wind / Temperature at treeline around -7 C / Freezing level valley bottom
Saturday
Cloudy with flurries; 5-15 cm, then another 5-15 cm overnight / 30 km/h southeast ridgetop wind / Temperature at treeline around -6 C / Freezing level 900 m
Sunday
Mix of sun and cloud / 10 km/h east ridgetop wind / Temperature at treeline around -6 C / Freezing level 1000 m
Monday
Mostly cloudy / 15 km/h north ridgetop wind / Temperature at treeline around -7 C / Freezing level 700 m
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
- Use caution on large alpine slopes, especially around thin areas that may propagate to deeper instabilities.
- Cornice failure may trigger large avalanches.
Avalanche Problems
Wind Slabs
Wind slabs may remain reactive to human triggers on lee aspects in the alpine.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2
Persistent Slabs
A layer of facets sitting on a crust buried in January has recently been reactive in the White Pass area. Triggering is most likely in areas where the snowpack is thin and weak, or with a heavy load like a cornice fall or the weight of a smaller avalanche in motion triggering this deeper layer.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3