Stay alert to changing conditions. Avalanche hazard will increase at upper elevations as snow accumulates. Dial back terrain if you are seeing 20 cm of new snow.
New snow is expected to rapidly accumulate on Friday, accompanied with strong southwest winds and a gradual rise in temperature. Anticipate the development of a touchy, widespread storm slab problem as snow accumulates.
A fast-moving storm with intense snowfall and fierce wind moves in Friday
Thursday night: Clearing overnight, light west wind becoming southwest, treeline temperatures around -5 C, freezing level dropping to 300 m.
Friday: Increasing cloud, 5-15 cm of snow starting in the afternoon as an potent storm moves in overnight, southwest wind increasing to strong, treeline temperatures rising to -1 C, freezing level rising to 800 m by end of day.
Saturday: Cloudy, 40-70 cm of snow expected to accumulate by end of day, strong southwest wind, treeline temperatures rising to near 0 C overnight during heaviest precipitation and dropping through the day, freezing level rising to 1100m and dropping to 500 m by end of day.
Sunday: Cloudy, 15-25 cm of snow, moderate southwest wind, treeline temperatures near -4 C, freezing level around 500 m.
No recent avalanche activity has been reported.
A potent storm moves in Friday bringing 5-15 cm of new snow and strong southwest wind by late afternoon. This is expected to build increasingly reactive storm slabs at upper elevations.
We have uncertainty about the presence of a layer of surface hoar or facets above a substantial crust that formed in early December. Check out this MIN report from close to Mt. Gillespie on Sunday that shows these surface hoar crystals. Where weak snow above the crust exists, we anticipate a persistent slab problem to develop with rapid loading from the incoming storm. Send us your observations of what is above the crust where you are travelling using the Mountain Information Network.
Last week's rainy atmospheric river event has eroded snow depths at and below treeline to below the threshold depth for avalanches.
