Avalanche Forecast
Issued: Apr 12th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
jsmith,
Avalanche Canada
Lingering wind slabs may remain reactive to human triggers on lee aspects at treeline and above.
Watch for recently formed and reactive wind slabs as you transition into wind affected terrain.
Summary
Confidence
Moderate
Avalanche Summary
A naturally triggered size 2.5 wind slab was reported on a northeast aspect in the alpine on Wednesday.
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
20-40 cm of recent snowfall has been redistributed into wind slabs on north-to-east-facing terrain features by southwest winds. The recent snow sits over wind-affected surfaces or a crust on south-facing slopes.
A weak layer buried in late March exists as surface hoar and facets on north facing slopes and a crust elsewhere. It has produced recent avalanche activity in the coastal areas. This layer may become reactive here too with new snow loads.
The middle of the snowpack is strong and contains numerous hard crusts. Near the ground, weak faceted crystals exist. There hasn't been avalanche activity on this layer recently, but it remains on our radar as it may become active with abrupt changes to the snowpack, such as rapid loading (heavy snowfall or rain) or prolonged warming.
Weather Summary
Wednesday night
Mostly cloudy with isolated flurries; 0-5 cm / 20 km/h southwest ridgetop wind / Temperature at treeline around -8 C / Freezing level valley bottom
Thursday
Mostly cloudy with isolated flurries; 0-3 cm / 15 km/h southwest ridgetop wind / Temperature at treeline around -6 C / Freezing level 1100 m
Friday
Mix of sun and cloud / 20 km/h southeast ridgetop wind / Temperature at treeline around -5 C / Freezing level 1200 m
Saturday
Mix of sun and cloud with isolated flurries; 3-5 cm / 30 km/h southeast ridgetop wind / Temperature at treeline around -3 C / Freezing level 1400 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 freshly wind loaded terrain features.
- Cornice failure may trigger large avalanches.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Problems
Wind Slabs
Lingering wind slabs may remain reactive to human triggers on lee aspects at treeline and above.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 13th, 2023 4:00PM
