Avalanche Forecast
Regions: Olympics.
Dangerous avalanche conditions will persist Thursday, especially in terrain receiving wind transported snow. Lower elevations will begin to slowly stabilize. Avoid steep open slopes in higher terrain. Give safe margins near and below growing cornices. Storm snow is very deep! Tree-well and snow immersion hazards are very dangerous, so keep communication with your partner at all times.
Detailed Forecast
Moderate rain and snow late Wednesday should taper to light to moderate showers with a cooling trend overnight Wednesday and Thursday. Â
Increasing crest level winds are expected Wednesday night and Thursday.Â
The avalanche danger will lower slightly Thursday, but mainly at lower elevations with little wind exposure. Near and above treeline, strong winds should continue to build wind slabs along lee slopes below ridges and exposed open terrain.
Dangerous avalanche conditions will persist due to the likelihood for triggering a large and potentially deadly avalanche. Recent storm and wind slabs will require time to heal, so be patient and match your terrain selection appropriately.
Significantly transformed snow conditions have taken place during this extended storm cycle. Tree-well and snow immersion hazards are very dangerous, so keep communication with your partner at all times.
Snowpack Discussion
The NWAC weather station at Hurricane Ridge has received 7 inches of water equivalent over the past 7 days. It appears all that has fallen as snow with the total depth at Hurricane Ridge increasing 40 inches since 1/17.Â
An estimated 3-4 feet of snow rests above the most recent crust on sheltered slopes. Moderate to occasionally strong S-SW winds have continued to transport new and recent snowfall in the Hurricane Ridge area over the last several days. Two separate avalanche cycles may have occurred since Sunday. New storm snow instabilities have had little time to settle due to the consistent loading in the Hurricane Ridge area during this extended storm cycle.Â
A high degree of uncertainty exists in this area due to the lack of observations over the last week, however weather station data would support significant storm and wind slabs exist in the Hurricane Ridge area.
Observations
No recent observations
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, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
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: All elevations.
Likelihood: Possible
Expected Size: 1 - 1