Avalanche Forecast
Regions: Cascades - North West.
Very dangerous avalanche conditions will continue in the Mt. Baker area with the possibility for very large and destructive avalanches on Tuesday. Be aware of overhead terrain where avalanches may run well into the tracks and runouts.
Detailed Forecast
Here we go again - a frontal system will bring another round of snowfall to the Mt. Baker area Tuesday with the potential for 10-15 inches of snow during the day. There should be less wind and warming versus Sunday's system, but the additional loading on the back of this already active storm cycle will once again ramp up the avalanche danger in the Mt. Baker area Tuesday. Backcountry travel in avalanche terrain should be avoided Tuesday.Â
Recent storm instabilities have not had time to settle and stabilize. Storm slabs will entrain copious amounts of recent snowfall, quickly becoming large and dangerous.Â
Recent wind slabs lurk beneath the lower density snow at all elevations. Many of these older wind slabs are very deep. Fresh or deeper recent wind slabs may produce large or even very large avalanches, entraining significant amounts of loose dry snow.
Be aware of overhead terrain where avalanches may run well into the tracks and runouts. Very dangerous avalanche conditions will continue with the possibility for very large and destructive avalanches on Tuesday.
Deep snow exists throughout the Mt Baker area. Snow immersion and tree-well hazards continue to increase and pose significant danger. Maintain constant communication with your travel partners.
Snowpack Discussion
A very active weather pattern over the last week continues to target the Mt Baker area. More than 5 feet of snow sits above the most recent melt-freeze crust - it is deep out there! The most recent storm cycle wrapped up Sunday night with cooler temperatures, light winds and snow showers adding an additional 8 inches Monday.Â
Besides the consistent moderate to heavy snowfall seen during Sunday's storm, strong winds transported snow forming wind slabs on a variety of aspects. Many of these wind slabs are very deep. Storm slabs were easy to trigger on Sunday and again on Monday.Â
Poor visibility and frequent storm conditions have limited observations above treeline during this period.Â
Observations:Â
An avalanche professional in the Glacier Creek area reported little wind and occasionally heavy snow showers on Monday. A reactive storm layer within the most recent storm snow allowed storm slabs of 6-10" to be easily triggered on all aspects up to 5600'. A few natural storm slabs were observed as well.Â
On Monday morning, Mt. Baker pro-patrol reported control results producing widespread and easily-triggered 1'+ soft slab or loose dry avalanches that broke wide and ran far. Poor visibility prevented observations into the surrounding backcountry terrain.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: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 2