Avalanche Forecast
Regions: Stevens Pass.
The avalanche danger Friday will center around wet avalanche concerns and become increasingly dangerous with elevation.
Detailed Forecast
Moist and mild southwesterly flow will carry wet fronts across the area Thursday night and Friday. Snow levels will remain high, around 7000 feet, before beginning to cool later Friday afternoon.Â
The avalanche danger Friday will center around wet avalanche concerns and increase with elevation. Small loose wet and wet slab avalanches are possible below treeline, with the potential for larger wet avalanches near and above treeline where more recent snow is available for entrainment above the most recent rain crust. Isolated glide avalanches cannot be ruled in any elevation band where smooth rock surfaces become lubricated by continuing rainfall and the entire snowpack releases.
Friday will be a poor day for backcountry travel no matter how you cut it.  Â
Remember, due to the unseasonably low snowpack especially at lower elevations, numerous terrain hazards such as open creeks, partially covered rocks and vegetation are widespread. Â
Snowpack Discussion
Mild weather the last week of January led to significant snowpack consolidation. Surface hoar formed during the end of January below treeline has likely been destroyed by intermittent bouts of rain earlier this week and not reported as an active layer in recent avalanches.Â
The snow level oscillated around 4000 feet this week... with a few inches of new snow accumulating generally near and above treeline. The most new snow and wind transport occurred in the Mt. Baker area near and above treeline early this week.Â
NWAC observers this week reported small wet loose avalanches involving new and shallow storm snow in the Stevens Pass and Paradise areas. In the Mt. Baker area on Monday, wind transport of new storm snow was evident near and above treeline and cornice breaks were noted near Artist's Points.Â
Observer Tom C. was in the Rainy Pass area near Stevens on Thursday. With a transition to rain in the late morning, Tom observed natural small wet loose and wet slabs releasing on steeper slopes below treeline involving the most recent snow over a rain crust. Â
Small wet loose, Rainy Creek. 2-5-15 by T. Curtis
The mid and lower snowpack west of the crest should consist of layers of stable consolidated rounded grains or melt forms and crusts from multiple warm periods this winter.
Avalanche Problems
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: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 1
Wet Slabs
Release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slab avalanches can be very destructive.
Avoid terrain where and when you suspect Wet Slab avalanche activity. Give yourself a wide safety buffer to handle the uncertainty
A Wet Slab avalanche. In this avalanche, the meltwater pooled above a dusty layer of snow. Note all the smaller wet loose avalanches to either side.
Wet slabs occur when there is liquid water in the snowpack, and can release during the first few days of a warming period. Travel early in the day and avoiding avalanche paths when you see pinwheels, roller balls, loose wet avalanches, and during rain-on-snow events.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1