Avalanche Forecast

Fair - Intensity of incoming weather systems is uncertain

A series of wet storms are set to impact the coast until Tuesday morning then a cooling trend. Saturday night: 15-25 mm precip can be expected between 4pm Saturday and 4am Sunday with freezing levels around 1700 m and strong southwesterly winds. Sunday: A further 15-25 mm precip is expected with freezing levels around 1900 m and southwest ridgetop winds gusting to 60 km/h. Monday: Another pulse looks to bring 10-20 mm precip with freezing levels around 1900 m and southwest ridgetop winds gusting to 60 km/h. Tuesday: Possibility of lingering storms that could bring highly variable precipitation. A cooling trend is expected to lower freezing levels to around 1000 m. Winds are expected to diminish.

Over the past week, very large slab avalanches have been running on the mid-March persistent weak layer. What makes this spooky is that the majority of these avalanches have been remote triggered, some from as far as 200m away. This interface remains very reactive. While it's a few days old now, the photo in this Mountain Information Network post provides a very powerful visual: https://bit.ly/1CS2Nld

This region has a very serious persistent slab problem that exists under the upper layers of dense storm snow. Depending on how much recent snow has fallen, a facet/crust persistent weak layer buried mid-March lies anywhere from 50-150 cm below the surface. This interface has been incredibly volatile recently and remains sensitive to human triggering, especially where the slab is thinner. Recent compression tests have produced sudden planar failures at this interface. At lower elevations, rain has saturated the snowpack. Layers below the critical mid-March interface are generally considered to be well-settled and strong.