Avalanche Forecast
Issued: Jan 20th, 2018 4:32PM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
High -
Weather Forecast
Sunday: A mix of sun and cloud with isolated flurries and a trace of new snow. Strong southwest winds. Alpine high temperatures around -7Monday: A mix of sun and cloud with isolated flurries and a trace of new snow. Strong southwest winds. Alpine high temperatures of -8.Tuesday: Cloudy with sunny periods. Moderate southwest winds. Alpine high temperatures of -9.
Avalanche Summary
Reports from the southeast of the region on Friday showed several small (Size 1) loose dry slides releasing with ski cutting in steep terrain around treeline. Only one natural storm slab release (Size 1.5) has been reported since Thursday's storm. The slab depth was roughly 20cm and it also occurred in the southeast of the region. Improving visibility may allow for more observations of recent activity.Looking forward, expect ongoing moderate to strong winds to promote lee loading as well as slab formation and reactivity even as snowfall tapers off.
Snowpack Summary
Up to 30 cm of new snow from last week's storm has buried both a new layer of feathery surface hoar in sheltered areas as well as sun crust on solar aspects. The new snow will need time to form a reliable bond to this previous surface. Moderate to strong winds have also been encouraging slab formation at higher elevations and continuously loading loose snow into deeper wind slabs in lee areas. Beneath the new snow, Previous southwest winds formed wind slabs that are now buried in lee terrain at higher elevations.An unstable weak layer from mid-December (predominantly feathery surface hoar crystals and/or a sun crust) is found at treeline and below treeline elevations. Deeper in the snowpack, an early-season rain crust and sugary facets exists. Slabs may still fail on these layers under the weight of a person, a machine, or large wind slab release. Although the snowpack structure is variable across the region, these persistent slab problems are generally widespread. Snowpack depths are across the region are similarly variable, but typically shallower in the east.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 21st, 2018 2:00PM