Avalanche Forecast
Regions: Cascades - North West.
Natural or human triggered wind and storm slab should be likely or very likely near and above treeline on Saturday. Travel in avalanche terrain is not recommended on Saturday.
Detailed Forecast
Update Saturday morning: A north/south oriented front and heavy moisture with a warming trend is over the Olympics and north Cascades on Saturday morning. The patrol at Mt Baker reports natural wind and storm slab and widespread 10 inch wind and storm slab on Saturday morning with sympathetic and remote triggering. Travel in avalanche terrain in the Mt Baker area is currently not recommended on Saturday.
There will be a lot of difference in conditions depending on elevation in this area on Saturday!
If you venture out at low elevations use caution where creeks, rocks and other early season terrain hazards lurk just below the surface; your body and equipment will thank you!Â
Snowpack Discussion
Mt. Baker was the hands down winner over the last 48 hours, with almost 4 feet of snow through Friday afternoon! Crystal, Chinook and Paradise also did quite well with 1-2 feet over the same time period. Lower storm totals were seen elsewhere including the Cascade Passes. Â
Along the west slopes of the Cascades we heard from Crystal mountain pro-patrol today. Morning avalanche control work at Crystal produced widespread 8-10" storm slabs that released within the new storm snow. Storm slabs were the most sensitive in areas with the least wind effect. We also heard from the NPS ranger at Paradise that a skier triggered storm slab caught and carried a skier on a SE aspect of Mazama Bowl Friday afternoon. The shallow slab was about 10 cm (4") deep, 30 m across and ran 25 m vertically, failing within the storm snow. The skier went for a ride but was uninjured. We expect that in the Mt. Baker area where due to the higher storm totals, storms slabs were more reactive and deeper.Â
Below treeline new snow has begun to cover terrain anchors and fill in creeks, though many areas need more snow to transform the landscape to full winter conditions. This particularly applies to the Cascade Passes where the snowdepth is still quite shallow. Â
It's early season and the forecasts are based on limited field observations. Keep that fact in the forefront of your mind if entering avalanche terrain this weekend.Â
Avalanche Problems
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: Very Likely
Expected Size: 1 - 1
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: Very Likely
Expected Size: 1 - 1