Hazard may change dependent on the amount of new snow. More snow than forecast may push the hazard rating higher than the forecast.
Confidence
Fair - Intensity of incoming weather systems is uncertain
Weather Forecast
A series of Pacific storms will bring snow to the forecast area for the next 7 to 10 days. Forecast models vary on amounts and some parts of the area may see larger amounts of precipitation.Tuesday night: Freezing Level: Valley bottom; Precip: 5-10cm Wind: Light to moderate south west, and strong west to south west at ridge top.Wednesday: Freezing Level: 1100m; Precip: 5-10cm Wind: Moderate south west and strong to extreme south west at ridge top.Thursday: Freezing level: 1100m; Precip: 5-10cm Wind: Generally west and moderate to strong at ridge top.Friday: Freezing level: 900m; Precip: 5-10cm Wind: South moderate, gusting to strong at ridge top.
Avalanche Summary
Numerous size 1 to 1.5 skier controlled and natural avalanches have been reported in the past 24 hrs. Expect the size and number to increase with increased snowfall and strong ridge top winds.
Snowpack Summary
The new storm snow is sitting on a variety of old surfaces that include multiple layers of surface hoar, facetted snow from the past few weeks of cold clear weather, with some old suncrust on steep south facing slopes. Moderate temperatures in the forecast should help with bonding, but redistribution by strong ridge top winds will create wind slabs on lee slopes. These wind slabs will be a prime cause for concern for the near future. In some parts of the forecast area there exists areas of shallow snowpack that should be regarded as potential locations to trigger large destructive avalanches.
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.