We have some uncertainty in the likelihood and distribution of persistent slabs. In times of uncertainty, conservative terrain choices are the best defense.
Rider triggerable wind slabs could still linger in the alpine. If triggered, wind slabs may step down to deeper layers, causing larger avalanches.
A persistent weak layer is buried 1 - 2 m. This is a low-probability, high-consequence problem. Signs of instability may not be obvious. The best defence is smaller, low-consequence terrain.
On Tuesday our field team reported a recent cornice-triggered size 3 persistent slab avalanche on a northeast aspect that ran to valley bottom.
On Monday, this MIN reported a size 2 natural wind slab but no results on ski cuts or other signs of instability.
Over the weekend a few dry loose avalanches were observed in steep terrain. A skier accidentally triggered a cornice while trying to access a ski line, this resulted in a dry loose avalanche on the slope below.
New snow dusts wind-pressed surfaces and wind slab in exposed alpine terrain. 20 to 40 cm of soft snow from last week can be found in wind-sheltered areas. Reports suggest this snow is bonding fairly well to previous surfaces.
A thick crust from late January can be found at a wide range of depths, from 75 to 150 cm. Where it is shallowest, facets are most likely to exist above it, and the more problematic it is expected to be.
We do not have concerns about the snowpack below this layer.
Wednesday Night
Mostly cloudy. 10 km/h southeast ridgetop wind. Treeline temperature -4 °C.
Thursday
Mostly sunny. 10 km/h southwest ridgetop wind. Treeline temperature -3 °C.
Friday
Mix of sun and clouds. 2 to 5 cm of snow. 50 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1100 m.
Saturday
Mix of sun and clouds. 1 to 10 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -3 °C.
More details can be found in the Mountain Weather Forecast.
