Brief periods of sunshine could destabilize the surface snow on Sunday morning. Be alert for lingering wind slabs up in the alpine in the north of the region.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain on Sunday
Weather Forecast
There may be sunny breaks on Sunday morning before some convective flurries in the afternoon, with brief periods of intense precipitation. Temperatures are staying cool for this time of year. SUNDAY: A mix of sun and cloud with convective flurries in the afternoon (3-5cm possible) / Light to moderate south west wind / Alpine temperature -6 / Freezing level decreasing to 500m in the afternoonMONDAY: Mix of sun and cloud / Light to moderate west wind / Alpine temperature -5 / Freezing level 700m TUESDAY: Cloudy with sunny periods / Light west wind / Alpine temperature -5 / Freezing level 800m.
Avalanche Summary
A few wet loose natural avalanches to size 1 were reported on sunny aspects on Saturday. We'd expect the same on Sunday with warming temperatures and direct sun.
Snowpack Summary
At tree line and below, we're into a spring cycle with a good re-freeze overnight (supportive crust) followed by daytime warming to +6 and wet surface snow. New snow amounts over the past three days (1-8cm) have been absorbed into the spring snowpack cycle. Alpine areas around Squamish likely received about 60-100 cm of storm snow and more wind early last week. In these areas the more recent snow is possibly sitting on a mixture of weak grains including a crust on solar aspects and potentially facets/surface hoar on polar aspects. Below the storm snow the snowpack is generally well settled and strong.
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.