Northwest Coastal

A Special Public Avalanche Warning is in effect for this region. Another 30-50 cm of new snow will drive the avalanche danger on Sunday.

Moderate - Intensity of incoming weather systems is uncertain on Sunday

SATURDAY NIGHT: 20-30 cm of snow, strong to extreme wind out of the southeast, alpine temperatures around -5 C.SUNDAY: Another 10-20 cm of snow throughout the day, wind easing but still strong from the south, freezing level steady around 800 m, alpine high temperatures around -5 C.MONDAY: Steady flurries with localized accumulations of 10-20 cm, strong wind from the south, freezing level steady around 800 m, alpine high temperatures around -5 C.TUESDAY: Another front approaches and brings 20-35 cm of snow, strong wind from the southwest, freezing level steady around 800 m, alpine high temperatures around -5 C.

A few size 1-2 natural avalanches were reported in steep terrain features on Saturday in the Shames and Terrace area. Some larger natural avalanches were reported in north-facing terrain on Friday. There have been several reports of skiers in the Shames area feeling large settlements in low angle terrain (whumpfs), a sign that the storm slabs would be very reactive to human-triggering in steeper terrain.Harsh weather conditions have limited observations over the past week, but with the enormous amount of snowfall there have likely been several cycles of natural avalanche activity.

The onslaught of storms continues with another 30-50 cm of new snow possible by the end of the day on Sunday. Both snowfall amounts and wind effect will be more pronounced near the coast.A total of 100-150 cm of recent storm snow sits above a potential weak layer. This layer is composed of surface hoar, weak facets (sugary snow), and crusts. The surface hoar is likely to be especially prominent on sheltered slopes at treeline while surface faceting was likely more widespread. Reports from the Shames area on Saturday suggest the storm snow is bonding poorly to this layer (as indicated in snowpack tests and whumpfing).Deeper in the snowpack, there are reports of several crusts including an early season crust with facets near the bottom of the snowpack.