This is an ARCHIVED advisory from avalanche.ca
It is archived as part of the avalanche-center.org incident records

Date Issued: Saturday, January 27, 2024 at 04:00
Valid Until: Sunday, January 28, 2024 at 04:00
Prepared by: ahanna

Wind slabs sitting over a weak layer may become increasingly reactive as temperatures start to rise this weekend.

Saturday
Alpine: 3 - Considerable
Treeline: 2 - Moderate
Below Treeline: 2 - Moderate

Travel and Terrain Advice

    Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
    Extra caution for areas experiencing rapidly warming temperatures for the first time.
    A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
	
Avalanche Problem 1: Wind slab
Elevation: Treeline, Alpine
Slopes: North, Northeast, East, Southeast, Northwest
Chances of Avalanches: Possible
Expected Size: Small - Large

Wind has transported recent snow into wind slabs on north to east aspects at upper elevations. Wind slabs sit over a weak layer of facets and may be sensitive to trigger and propagate widely.


Avalanche Problem 2: Wet Loose
What Elevation: Below treeline
Which Slopes: North, Northeast, East, Southeast, south, Southwest, West, Northwest
Chances of Avalanches: Possible
Expected Size: Small - Small

Loose wet avalanches will become increasingly likely as temperatures rise above freezing. 


Avalanche Summary

A few wind slab avalanches were reported east of Prince George on Thursday. They were skier-controlled size 1.5 on steep north-facing convex rolls, running on the January facet layer.

Snowpack Summary

Recent snow has been redistributed by wind at upper elevations. At lower elevations, a thin crust or moist snow may be found at the surface.

20-40 cm of snow sits over a layer of facets formed during the mid January cold snap. Bonding at this interface varies through the region.

A prominent crust is found 30 to 50 cm deep. It extends up to 1900 m in the Cariboos and up to 1400 m around Pine Pass. In the Sugarbowl area, a layer of small surface hoar or facets has been observed near the crust.

The midpack is generally strong and well bonded, except for areas east of the Divide, where the snowpack is shallow and faceted with depths of 60 to 100 cm around treeline.

Weather Summary

Friday night

Mostly cloudy with flurries bringing a trace to 5 cm of snow. Southwest alpine wind 30-50 km/h. Treeline temperature 0 °C. Freezing level 1500 m.

Saturday

A mix of sun and cloud. Southwest alpine wind 30-50 km/h. Treeline temperature +2 °C. Freezing level 2000 m.


Confidence: Moderate

    Uncertainty is due to how the snowpack will react to the forecast weather.