Regions
Northwest Coastal.
The weather is due to change with snowfall forecast for Wednesday and Thursday. Avalanche danger will gradually increase as the snow starts to accumulate Thursday.
Confidence
Low - Due to the number of field observations
Weather Forecast
TUESDAY: Mix of sun and cloud. Light southwest wind. Alpine temperature -2. Freezing level 1100 m. WEDNESDAY: Flurries, accumulation 5-10cm. Light to moderate south wind. Alpine temperature -2. Freezing level 1100 m. THURSDAY: Periods of snow, accumulation 10-20cm. Moderate south wind. Alpine temperature -1. Freezing level 1200 m.
Avalanche Summary
Reports from this weekend indicate loose wet activity on steep slopes facing the sun at tree line and in the alpine. These avalanches were reported as size 1-2 and were isolated to the recent surface snow only. Several naturally triggered wind slabs up to size 2 on steep alpine features were reported near Bear Pass on Saturday.
Snowpack Summary
10-20 cm of recent storm snow and strong variable winds have formed wind slabs on a variety of aspects at treeline and above.In the south of the region, two layers of surface hoar are buried early-March and mid-March are approximately 70-100 cm deep. The layers are most prominent on north to east aspects and were buried In the north of the region, these layers are around 40 cm deep.Bellow these March layers the mid-pack is generally well-settled and strong. However, in the portions of the region with a shallower snowpack, such as the far north, have weak sugary facets near the bottom of the snowpack.
Problems
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.
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.