Avalanche Forecast
Issued: Apr 19th, 2023 4:00PM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeWind slabs may linger in lee terrain features. Small avalanches could step down to a buried layer and form large avalanches.
Summary
Confidence
Moderate
Avalanche Summary
We haven't received any recent reports of avalanche observations. The most recent avalanches occurred about a week ago on the facet layer described in the Snowpack Summary (e.g., this MIN).
Snowpack Summary
Around 10 to 20 cm of snow fell since the weekend with periods of strong southerly wind, which may have formed wind slabs in lee terrain features. The snow may not bond well to underlying layers, including faceted snow in shaded aspects at high elevations or a hard melt-freeze crust found on all aspects up to 1700 m and to mountain tops on southerly slopes.
A layer of facets and a crust from early April is buried up to 60 cm at treeline and alpine elevations. There's uncertainty in how this layer is bonding, but it was the culprit of many large avalanches around April 12.
The base of the snowpack remains faceted and weak. We haven't received any notes of recent avalanche activity on this layer, but the concern remains for steep and rocky slopes with a thin snowpack.
Cornices are large and looming at this time of year.
Weather Summary
Wednesday Night
Clear skies with no precipitation, 10 km/h southwest wind, treeline temperature -7 °C.
Thursday
Cloudy with afternoon snowfall, accumulation 1 to 3 cm, 20 to 40 km/h south wind, treeline temperature -6 °C, freezing level 1200 m.
FridayCloudy with snowfall, accumulation 5 cm, 20 km/h southwest wind, treeline temperature -3 °C, freezing level 1600 m.
SaturdayCloudy with snowfall, accumulation 2 to 5 cm, 20 to 40 km/h south wind, treeline temperature -1 °C, freezing level 1700 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Approach lee and cross-loaded slopes with caution.
- Use ridges or ribs to avoid areas of wind loaded snow.
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Wind slabs may linger in lee terrain features from recent snow and strong southerly wind. Small avalanches could step down to a layer of facets and a crust buried 60 cm that could result in large avalanches.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 20th, 2023 4:00PM