Regions
Northwest Coastal.
Forecast new snow and strong winds are expected to create touchy storm slabs reactive to human triggers; especially in wind affected terrain.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
THURSDAY: Snow; accumulation 10-15 cm. Strong southwest wind. Alpine temperature -1. Freezing level 1000 m. THURSDAY NIGHT: Snow; accumulation 10-15 cm. Strong southwest wind. Freezing level 800 m. FRIDAY: Snow; accumulation 5-15 cm. Moderate to strong south wind. Alpine temperature -1. Freezing level 1000 m.SATURDAY: Cloudy with flurries. Light west wind. Alpine temperature -1. Freezing level 1000 m.
Avalanche Summary
No new avalanches were reported in this region on Tuesday. However, I would expect the incoming storm on Thursday to form fresh storm slabs reactive to human triggers; especially in wind affected terrain at treeline and above.
Snowpack Summary
The incoming snow and strong winds on Thursday will create touchy storm slabs 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 and most prominent on north to east aspects. Further north, these layers are around 40 cm deep.Below these March layers the mid-pack is generally well-settled and strong. However in the far north of the region there are weak sugary facets near the bottom of the snowpack.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.