Avalanche Forecast
Regions: Olympics.
The weather should have limited effects on snow conditions on Thursday. Mainly watch for lingering areas of firmer wind slab on previous lee slopes.
Detailed Forecast
A weak dissipating front should move through an upper ridge and across the Northwest on Thursday. This should cause some light rain or snow in most areas of the Olympics with a minor drop in snow levels.
This weather should have limited effects on snow conditions in the Olympics.
Mainly watch for lingering areas of firmer wind transported snow and wind slab on previous lee slopes from the back end of the storm early this week.
New snow amounts should be limited on Thursday and any new wind slab should be unlikely, shallow and small if any.
Loose wet avalanches will not be indicated due to the cloud cover and cooling. Storm slab will also not be listed due to the expected limited amounts of new snow.Â
As a general backcountry travel safety note, tread carefully at lower elevations and on wind scoured aspects where terrain hazards (exposed rocks, trees, streams, etc.) are present.Â
Snowpack Discussion
Strong southwest flow carried a wet front across the Olympic Saturday night. The front tapped subtropical moisture which pushed snow levels high and resulted in about 1 inch of rain at the NWAC site at Hurricane. Snow on the back end of this storm Sunday and Monday was about 7 inches.
NWAC pro-observer Katy Reid was at Hurricane on Sunday. She mainly reported poor coverage and shallow new snow well bonded to previous MF snow. She also reported stable MF layers in the mid and base pack where it existed. Here is her video from Sunday on our YouTube Channel.
Some sun with mild temperatures is being seen west of the crest on Wednesday. Small loose wet avalanches might be possible on steep solar slopes.
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.
Likelihood: Unlikely
Expected Size: 1 - 1