Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Regions
Northwest Coastal.
Above freezing temperatures are possible near treeline on Thursday. This could make wind slabs more sensitive to triggering.
Confidence
Poor - Due to the number of field observations
Weather Forecast
Thursday: A mix of sun and cloud with an above freezing layer developing somewhere around 1500 m. Friday: Increasing cloud with precipitation beginning during the day. Moderate accumulations are expected. The freezing level should rise to 1000m by Saturday morning. Winds increase to moderate or strong from the S-SE. Saturday: Continued light to moderate precip. The freezing level continues to climb and ridge winds remain strong.
Avalanche Summary
There are no new reports of natural or rider triggered avalanches. Please let us know what you're seeing out there. Email us at [email protected].
Snowpack Summary
Conditions vary significantly throughout the region, at different elevations, and on different aspects. The common theme is that the snowpack is generally shallow, quite facetted (sugary), and wind affected. In the past couple days we've seen 15-40 cm of low density snow fall. This snow buries a previous surface that was heavily wind affected, with possible pockets of surface. New dense wind slabs may be found on a variety of aspects in open terrain. The mid-November crust-facet layer is now 40-60 cm deep and continues to show easy to moderate shears in snowpack tests. Deeper in the snowpack, at 80 cm down there is another crust that is breaking down and becoming bonded to the surrounding snow.
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.