Avalanche Forecast

Sunny and generally much warmer weather will be seen on Sunday with light winds.

This weather will help to further gradually stabilize previous wind slab layers leading to an overall decreasing danger. But continue to watch for signs of wind transported snow near ridges or on specific terrain features such steep rollovers on Sunday especially in the alpine and near treeline areas.

Heads up also that it will be sunny and warm and wet loose avalanches may be possible on steep solar aspects. There was a foot of snow in the alpine in the north to central Cascades near and west of the crest Thursday night. Watch for initial signs of damp loose snow such as roller balls and damp surface snow deeper than a few inches or natural loose snow releases. Wet loose snow avalanches would be most likely on steep solar slopes in gullies and cirques receiving sun. But solar input is also at its least at this time of year so damp or wet snow should not be extensive.

A front crossed the Northwest Thursday afternoon and night. Temperatures began quite warm and cooled during the storm. This initially produced rain or wet snow that gradually turned to snow eventually reaching lower elevations.  Numerous reports indicate this caused a favorable profiles in the new snow and good bonding of new snow to previous wet snow. New snow amounts vary from north to south and with elevation. Upper elevations and areas in the north received about 20-30 cm (8-12 inches) new snow with lower elevations and areas in the south getting about 10-20 cm (4-8 inches).

The older snowpack consists mainly of  a mix of crusts and consolidated old snow layers.  Recent dry  and warm periods helped to consolidate and stabilized the older snowpack and eliminate weak layers near and west of the crest per numerous recent field tests.  There are some older faceted layers both above and below a mid December melt-freeze crust in some areas, however multiple bridging crusts are generally present in the upper snowpack and the weaker grains are showing rounding. 

The biggest current concern would be for any newly formed wind slab layers as Thursday's front was accompanied by very strong ridge top winds, initially southwesterly, shifting to northwesterly.  A photo of one ski triggered storm slab from Friday at Stevens Pass by NWAC observer Tom Curtis is below.

But while winds were strong with wind transport evident in many areas, multiple tests have all indicated an overall good stability and most new snow has been non-reactive to ski tests, stability tests and most explosive tests.

Sunny but cool weather should not greatly change conditions on Saturday.

Snowdepths remain well below normal, generally ranging from 1-2 meters in the alpine regions to less than 1 meter near and below treeline with significantly lower snowdepths below about 3500 feet. 

There will be less danger in areas that received less snow such as Hurricane Ridge and Crystal Mountain. The avalanche danger will continue to be low at lower elevations due to the low snowpack.