Avalanche Forecast
Regions: Olympics.
Older wind slab will need to watched for mainly near ridges on Tuesday. Any new snowfall may form small shallow areas of storm slab.
Detailed Forecast
A couple more weak short waves and weak bands of precipitation should move out of a large weak trough and over the Northwest on Tuesday. This should cause periods of mostly light snow in the Olympics on Tuesday with a slight warming trend.
Older wind slab will need to watched for mainly near ridges on north to southeast slopes. These layers may be stubborn to trigger but watch for signs of firmer wind transported snow.
New snowfall should be light at Hurricane Ridge on Tuesday. Any new snowfall may shallowly bury surface hoar and near surface faceted snow from around New Years on shaded sheltered slopes. Although unlikely it may form small shallow areas of storm slab.
Snowpack Discussion
Fair weather was seen the last couple days of December through the weekend. This weather caused consolidation and stabilizing of snow from December. It also caused new surface hoar and near surface faceted snow in many sheltered areas.
NWAC pro observer Matt Schonwald was at Hurricane Ridge on New Years Day in warmer weather and found 1-2 inch sun crusts on south slopes and sastrugi and small building wind slab on north slopes. But he did not see any failures in snow pit tests. Some surface hoar was being preserved in shaded sheltered areas. Cornices had become more isolated.
A skier on Turns All Year also reported settled stable powder on north slopes on New Years Day.
Fair weather seen Sunday and Monday in the Olympics should not bring much change to Hurricane Ridge.
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Avalanche Problems
Wind Slabs
Release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Wind Slabs form in specific areas, and are confined to lee and cross-loaded terrain features. They can be avoided by sticking to sheltered or wind-scoured areas..
Wind Slab avalanche. Winds blew from left to right. The area above the ridge has been scoured, and the snow drifted into a wind slab on the slope below.
Wind slabs can take up to a week to stabilize. They are confined to lee and cross-loaded terrain features and can be avoided by sticking to sheltered or wind scoured areas.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 1
Storm Slabs
Release of a soft cohesive layer (a slab) of new snow that breaks within the storm snow or on the old snow surface. Storm-slab problems typically last between a few hours and few days. Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
You can reduce your risk from Storm Slabs by waiting a day or two after a storm before venturing into steep terrain. Storm slabs are most dangerous on slopes with terrain traps, such as timber, gullies, over cliffs, or terrain features that make it difficult for a rider to escape off the side.
Storm slabs usually stabilize within a few days, and release at or below the trigger point. They exist throughout the terrain, and can be avoided by waiting for the storm snow to stabilize.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely
Expected Size: 1 - 1