Avalanche Forecast
Regions: Snoqualmie Pass.
Be aware of heightened avalanche danger in steeper terrain and near terrain traps relating to wet avalanches.
Detailed Forecast
Sunday should be quite warm (freezing levels 11-12 kft) and mostly sunny, although periods of high clouds may affect the north Cascades.  Despite the high freezing levels, a few factors should help tamp down the avalanche danger Sunday; rain will have tapered off Saturday allowing the snowpack to drain, weak solar input, and stiff winds in the alpine will all help limit the likelihood of wet avalanches.
Keep in the mind that although the likelihood of triggering an avalanche is not great, the central and north Cascades have had more recent snow available for entrainment with the potential for larger slides near and above treeline.Â
Generally avoid steep slopes especially near terrain traps where you might be able to push off enough saturated snow to start an avalanche large enough to take you for a ride. Wet slabs, human or natural triggered, are unlikely Sunday but be aware of their destructive potential in the central and north Cascades.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
The most recent snow from last weekend became involved in generally small natural avalanches Friday and Friday night during periods of heavier rain and warmth. 48 hr storm totals through Sat AM for NWAC stations west of the crest were 1.5 to 3 inches of rain from Snoqualmie Pass and north and 0.25 - 1.5 inches south of Snoqualmie. Mt. Baker received the most precipitation and Crystal the least.
Our NWAC pro-observers were at Stevens Pass for a class Tuesday and found a potential persistent weak layer of 2 mm facets on the Jan 15th crust. Here is a link to the Instagram video. While in this particular pit it gave a pretty remarkable score of PST 15/100 End it will not be listed as an avalanche problem due to a lack of activity on this layer, inconsistent distribution and the fact is should require a very large trigger.
On Saturday, professional ski patrol across the west slopes resorts reported a very saturated upper snowpack and little in the way of new avalanche activity. One small glide avalanche released in a steep smooth rock section at Alpental.Â
West of the crest the middle and lower snowpack should consist mostly of stable rounded grains or melt forms and crusts from 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: Possible
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: Alpine, Treeline.
Likelihood: Unlikely
Expected Size: 1 - 2