Avalanche Forecast
Issued: Apr 17th, 2023 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeForecast snow and light to moderate northeast wind Monday night may form fresh wind slabs on lee features.
Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Summary
Confidence
Low
Avalanche Summary
A naturally triggered large wind slab avalanche was reported on a north facing slope in the alpine on Sunday. See MIN
A size 3 persistent slab avalanche was reported on a southeast aspect in the alpine west of Kelsall lake on Thursday. It was suspected to have been triggered by solar radiation.
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
20-30 cm of recent snow and light to moderate south wind may have formed wind slabs in isolated lee features in the alpine.
The recent snow sits over previously wind-affected snow surfaces on northerly aspects and sun crust on other aspects.
A weak layer of surface hoar/crust/facets buried in early January is now around 100 cm down in most areas. Operators continue to monitor this layer. A significant warming event or a large trigger (like a falling cornice) are the most likely things to activate this layer.
Weather Summary
Monday Night
Snow; 10-15 cm / 20 km/h northeast ridgetop wind / Temperature at treeline around -7 C / Freezing level valley bottom
Tuesday
Cloudy with flurries; 5-10 cm, then another 5-15 cm overnight / 30 km/h east ridgetop wind / Temperature at treeline around -2 C / Freezing level 1200 m
Wednesday
Mix of sun and cloud / 30 km/h east ridgetop wind / Temperature at treeline around -2 C / Freezing level 1300 m
Thursday
Mix of sun and cloud with isolated flurries; 0-3 cm / 30 km/h northeast ridgetop wind / Temperature at treeline around -4 C / Freezing level 1100 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.
- Cornice failure may trigger large avalanches.
Problems
Wind Slabs
Forecast snow and light to moderate northeast wind Monday night may form fresh wind slabs on lee features.
Aspects: South, South West, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 18th, 2023 4:00PM