Avalanche Forecast
Issued: Apr 13th, 2023 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeLingering and reactive wind slabs remain at higher elevations.
Seek out terrain that has not been wind-affected.
Summary
Confidence
Moderate
Avalanche Summary
A naturally triggered size 2.5 wind slab was reported on a northeast aspect in the alpine on Wednesday. It failed at a depth of 40 cm on what is expected to be a melt-freeze crust that developed before our last storm.
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
Thursday Night
Mostly cloudy with isolated flurries; 2-8 cm / 15 to 20 km/h southwest ridgetop wind / Temperature at treeline around -7 C
Friday
Mix of sun and cloud / trace / 25 to 35 km/h southeast ridgetop wind / Temperature at treeline around -4 C / Freezing level 1200 m
Saturday
Mostly cloudy with snow; 10 to 15 cm / 30 km/h south ridgetop wind gusts to 50 / Temperature at treeline around -3 C / Freezing level 1200 m
Sunday
Mostly cloudy; 3 to 6 cm / 15 to 25 km/h south winds / Temperature at treeline -4 C / Freezing level 1200 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, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 14th, 2023 4:00PM