Regions
Northwest Inland.
There is low confidence in this forecast due to limited observations. As always, and especially when confidence is low, it is essential to supplement this information with your own observations. And don't forget to post them to the MIN!
Weather Forecast
Expect another 3-8 cm by Wednesday morning accompanied by strong to extreme southerly winds and freezing levels spiking as high as 1200m. Lingering light flurries are expected for Wednesday with alpine winds easing to moderate westerlies and freezing levels dropping well below valley bottoms. Continued light snowfall is expected for Thursday with 2-5 cm of accumulation, moderate southwesterly alpine winds, and freezing levels rising throughout the day. The next major system is expected to make landfall early Friday morning with moderate snow, extreme winds and freezing levels as high as 1200 m.
Avalanche Summary
Recent reports include several Size 1.5 loose dry sluffs that ran surprisingly far from steep, rocky alpine start zones on southeast to east aspects.
Snowpack Summary
Early season snowpack observations are still limited in the region but there is likely enough snow for avalanches at treeline and above. The average snowpack depth at treeline is reported to be around 50-90cm, and there's around 120cm or more in the alpine. Approximately 10-15cm of recent snow buried a thin layer of surface hoar that grew late last week. Recent reports include moderate to hard, sudden collapse snowpack test results in facets above a thick rain crust from early November that can probably be found down approximately 20-40cm. Forecast warming and wind is expected to promote settlement and slab formation, increasing the sensitivity of this weakness.
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.