Snowfall intensities Saturday morning could produce rates of over 6 cm snowfall per hour! With heavy snowfall and strong wind, expect storm slabs to build in size and sensitivity through the day.
A crust with weak, facetted snow above and below is buried by roughly 50-150 cm of snow. This layer is unlikely to be human-triggered, the forecasted rapid and heavy load of new snow will stress the snowpack and may provide more insight into the dormancy of this deeper instability.
Snowfall intensities Saturday morning could produce rates of over 6 cm snowfall per hour! With heavy snowfall and strong wind, expect storm slabs to build in size and sensitivity through the day.
With freezing levels forecast to rise over the weekend, watch for rain falling on snow and saturating the snowpack. In the case of wet avalanches, the first 24 hours of rain-on-snow are the most hazardous as large, destructive avalanches are most likely to occur.
A fresh 10-15 cm snow accumulated Friday morning and buried a layer of weak, sugary, unconsolidated snow produced by the recent cold weather.
A number of layers persist deeper in the snowpack, consisting of facets, surface hoar, and crusts.
Total snow depths are roughly 90-140 cm at treeline and up to 200 cm in the alpine.
Friday explosives control work trigger size 1-2 slab avalanches up to 20 cm deep.
Please continue to post your observations and photos to the Mountain Information Network.
Friday night
Snow, 15-25 cm overnight. Alpine temperatures rise to -4 C by morning. Southwest wind 25-45 km/hr. Freezing level rising to 900 m.
Saturday
Heavy precipitation, strong winds, and rising freezing levels are forecast throughout the day. Expect to encounter a variety of precipitation forms including freezing rain at roadside elevations.
Heavy snowfall, 30-50 cm. Alpine high temperature -2 C. Ridgetop winds southwest 40 gusting to 75 km/hr. Freezing level rising to 1500-1700 m.
SundaySnow, wet flurries, or freezing rain, 15-30 cm. Alpine high temperature 0 C. Ridgetop winds southwest 30-60 km/hr. Freezing level rising above 2000 m.
MondaySnow, wet flurries, or rain, 50 mm. Alpine high temperature 0 C. Ridgetop winds southwest 40 gusting to 90 km/hr. Freezing level 2000 m.
More details can be found in the Mountain Weather Forecast.
