A good sized storm is poised to hit the region late on Friday. Avalanche danger will increase accordingly.
Confidence
Fair - Timing of incoming weather is uncertain on Friday
Weather Forecast
Synopsis: A storm impacts this region late on Friday.Thursday: Dry. Winds light westerly. Freezing level around 1000 m.Friday: 5-10 cm new snow is expected, starting late in the day. Extreme southwesterly winds to 90 km/h at ridgetop. Freezing level 1100 m.Saturday: Light snow in the morning, dry in the afternoon. Winds becoming light northwesterly. Freezing level 1000 m.
Avalanche Summary
Small loose snow avalanches have been reported in the recent new snow.
Snowpack Summary
Southeastern parts of the region have seen 30-50cm new snow in the last few days, while western areas have seen more like 10-20 cm. Mostly this snow has been light and overlies old wind slabs on higher north and east facing terrain and sun crusts on solar aspects. There may be localized areas where the wind has blown the new snow into isolated wind slabs in exposed areas. A surface hoar/facet/sun crust layer from mid February (12th) may be buried in the top 35 cm or so, but has not been widely reported from this region. Mid and lower snowpack layers are generally well settled and stable.
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.