Avalanche Forecast
Regions: Olympics.
Older wind slab and possible loose wet avalanches should be the main problems to watch for at Hurricane on Wednesday.
Detailed Forecast
A large weak low pressure system will drift toward California on Wednesday. A shot of drier air with some weak light showers should eject from the low and over the Northwest. This may bring some light snow showers to Hurricane with slightly warmer temperatures.
Mostly older wind slab will still need to be watched for at Hurricane mainly on north to east slopes. Look for signs of firmer wind transported snow that can indicate wind slab layers.
Some sun or solar effects and slightly warmer temperatures should also be seen on Wednesday. Loose wet avalanches seem like a possible bet as well on steep solar slopes. Watch for wet snow deeper than a few inches and initial natural small loose wet releases on solar slopes that usually precede loose wet avalanches.
Snowpack Discussion
Fair weather was seen for almost a week around the New Year. This weather should have caused consolidation and stabilizing of snow from December at Hurricane.
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 some 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 continued Sunday and Monday at Hurricane. Some light snow may have been seen there on Tuesday.
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
Loose Wet
Release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. They generally move slowly, but can contain enough mass to cause significant damage to trees, cars or buildings. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
Travel when the snow surface is colder and stronger. Plan your trips to avoid crossing on or under very steep slopes in the afternoon. Move to colder, shadier slopes once the snow surface turns slushly. Avoid steep, sunlit slopes above terrain traps, cliffs areas and long sustained steep pitches.
Several loose wet avalanches, and lots of pinwheels and roller balls.
Loose wet avalanches occur where water is running through the snowpack, and release at or below the trigger point. Avoid terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.
Aspects: South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 1