Avalanche Forecast

Moderate

Debris from several large avalanches was observed in the runouts of the MacDonald gullies on Friday. Poor visibility likely hid an avalanche cycle at upper elevations from view.

On Thursday, a size 1.5 slab was observed from just lookers left of the Grizzly couloir.

Up to 20cm and counting has fallen today, Friday, and has built fresh storm slabs in smooth terrain.

As storm snow continues to pile up, it may overload the weak November 17th layer of surface hoar (5-30mm), facets, and crust. This buried surface hoar is largest at and below treeline, and will likely become a persistent avalanche problem as it gets more deeply buried over the weekend.

The early season snowpack is thin and variable, with an average depth of 50cm at the parking lots, just over a meter at treeline, and up to 130cm in the alpine. These values are below threshold for burying hazards, covering creeks, and bridging crevasses.

There will be a brief break between systems Friday night into Saturday morning.

A cold front from the NW will bring more snowfall starting Saturday evening, with an additional 15-25cm of accumulation by Sunday evening.

An Arctic high will bring clearing skies and plummeting temps into next week.

More details can be found in the Mountain Weather Forecast.

• Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
• Early season avalanches at any elevation have the potential to be particularly dangerous due to obstacles that are exposed or just below the surface.