Avalanche Forecast
Regions: Cascades - South East.
Lack of observations east of Cascade crest will require greater assessment of conditions by the back country travelers. Above treeline is mainly where there has been enough snow for wind to transport snow and form wind slab. Be especially wary of small loose wet avalanches on solar slopes near terrain traps.
Detailed Forecast
Little change should be seen on Saturday with mostly sunny weather, warm temperatures at higher elevations, light alpine winds, with inversions and cool temperatures in the Cascade passes and at lower elevations along the Cascade east slopes.
Especially in areas where the temperatures have become so mild, the snowpack should continue to gradually consolidate and strengthen, and the avalanche danger should continue to gradually decrease Friday to Saturday.
Above treeline is where there has was enough snow for wind to transport snow and form wind slab. More recent wind slab may be found on west-facing aspects and older wind slabs may be seen on more usual northwest to southeast aspects. Older wind slab should become increasingly stubborn, while newer, fresher wind slabs may be more reactive. Watch for areas of wind-scoured slopes which transport snow onto lee features and avoid the latter. These slabs should be small due to the limited amount of snow available for transport.
Snow on steep solar slopes should have mostly slid or consolidated in sunny warm weather late in the week. But continue to watch for loose wet snow on steep solar slopes especially near sun warmed terrain features.
Lack of observations east of the crest will require greater assessment of conditions by the backcountry traveler.
Early season terrain hazards still exist, such as poorly covered rocks, vegetation and creeks, particularly at lower elevations. Many areas below treeline in the central east and southeast Cascades will have too little snow for avalanches.
Snowpack Discussion
Warm, wet weather before Thanksgiving caused first storm, then wet snow avalanches in the Washington Pass area.  Post-Thanksgiving about 2 feet of snow accumulated in the Washington Pass area and this amount has settled above the Thanksgiving Day crust.
A series of frontal systems produced snow over the week following Thanksgiving at all stations in the Cascades: Locations on the east side of the Cascade crest had about 5-15".
An upper ridge this week has brought sunshine and greatly warming temperatures at higher elevations. Meanwhile an inversion and offshore surface flow is causing cool temperatures in the Cascade Passes and at low elevations along the Cascade east slopes. Winds have become light at most locations on Friday but moderate east winds have been seen such as at the top of Dirty Face Peak near Lake Wenatchee on Wednesday and Thursday.
Observations
North
A party of NCMG guides was in the Washington Pass area on Thursday and noted the temperature inversion at the Pass, good bonds to the Thanksgiving crust, some small loose wet activity on solar slopes, with little avalanche concerns below treeline.
Central
Last Saturday 12/2 , backcountry professionals skiing at Ingalls Peak reported generally stable conditions with some small, unreactive wind slab.
A report via the NWAC Observations for the Teanaway-Hawkins Mtn area for Wednesday indicated a new crop of surface hoar, stabilizing wind slab and a couple small loose wet avalanches on steep solar slopes.
The Mission pro-patrol on Friday reported generally to little snow for avalanches.
South
No recent observations.
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, West, North West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 1
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: South East, South, South West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1