Regions
Northwest Inland.
Happy New Year! Warm air and sun may create some touchy pockets of wind slab in the short term. Avalanche danger trending down for the weekend.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain
Weather Forecast
Mostly clear with freezing levels at valley bottoms and overnight valley temperatures around -18. Warm air has started to develop at higher elevations, between 1400-2100 metres. This warm air is not able to descend into the colder valleys. Forecast upper elevation southerly winds are expected to continue to push warmer air into the alpine. Saturday is forecast to be the warmest day of this inversion for the northwest inland region. Sunday may continue to have alpine temperatures at or slightly below freezing. Clear nights should allow for the snow surface to re-freeze.
Avalanche Summary
No recent avalanches have been reported. With solar radiation and warming forecast for the next few days, loose wet avalanches will become more likely on steep, sun-exposed slopes.
Snowpack Summary
Light amounts (10-15cm) of snow fell last weekend. Variable winds have likely shifted the new snow into wind slabs in upper elevation lee terrain. Although these wind slabs have likely gained strength, I'd remain cautious on steep, unsupported slopes in the immediate lee of ridge crests. Solar radiation has also come into play, and depending on the time of day, steep solar aspects may be moist or refrozen.We're still dealing with a thin, early-season snowpack for much of the Northwest Inland region. Shedin creek snow pillow is at historical minimum snow depth, and Tsai creek snow pillow is setting new historical minimum snow depth. Between 80 and 100 cm of snow can be found at tree-line in the south and west of the region, with closer to 60 cm in the east. A weak basal layer probably exists in most areas, and I suspect that the ongoing cold temperatures have continued to promote faceting in the snowpack, especially in shallow, rocky areas.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.