Avalanche Forecast
Issued: Jan 18th, 2018 5:00PM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate -
Weather Forecast
Friday: Mainly cloudy. Light variable winds. Alpine high temperatures around -5.Saturday: Mainly cloudy with isolated flurries and a trace of new snow. Light to moderate southeast winds. Alpine high temperatures of -5.Sunday: Mainly cloudy with isolated flurries and a trace of new snow. Moderate to strong east winds. Alpine high temperatures around -7.
Avalanche Summary
Reports from Wednesday include observations of thin (5 cm) storm slabs becoming highly reactive to skier traffic in the Howson Range, producing small remotely triggered (from a distance) and sympathetically triggered (by an adjacent release) slides. These small slabs were also running naturally in any terrain over a 37 degree incline.Reports from Monday included one remotely triggered Size 1 avalanche on a 50 cm deep surface hoar layer at 1000 m. Although small, this avalanche may be an indicator that the upper snowpack has settled into a more reactive slab.
Snowpack Summary
Snowfall from Wednesday and Thursday brought a variable 10-20 cm of new snow to the region. The new snow has buried a temperature crust left over from warm temperatures on the weekend. This crust likely exists well into the alpine. Beneath the crust, the same warm temperatures also worked to settle the upper snowpack, potentially forming a slab above buried weak layers in the top 50 cm of the snowpack. The potential weak layers include a few crusts and surface hoar layers that formed in early January and December. Recent reports suggest the snow is well bonded to most of these layers, but the recent settlement of the upper snowpack may have changed that.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 19th, 2018 2:00PM