Avalanche Forecast

A very weak front should cross the Northwest on Tuesday night and Wednesday morning. Little if any precipitation should be seen and there should be no big changes in snow conditions.

Clouds should decrease on Wednesday with cooler temperatures than the past couple days.

The main concern on Wednesday should be for small areas of slab layers on north or lee slopes. This should be mainly north to southeast slopes above tree line. Such layers would likely require larger triggers such as a falling cornice or a snow mobile.

Wet loose snow avalanches seem unlikely on Wednesday give all the recent consolidation, recent wet loose avalanche activity, cooler temperatures and potential high clouds and will not be listed as a concern. Avoid steep solar aspects or gullies in the sun if you see surface snow there deeper than a few inches or natural wet loose avalanches.

The most recent storm cycle to impact the Northwest was about 10-14 January.  The storm produced about 2 - 4 feet of snow at Hurricane and at most NWAC sites near and west of the crest. The tail end of the storm cycle 12-14 January was accompanied by a warming trend that brought rain to mid and low elevations and upside down heavy dense snow and slab layers to high elevations. The main slab avalanche activity in the recent storm cycle occurred on Sunday 12 January followed by large wet loose avalanches mainly on Tuesday 14 January.

Last Wednesday through today has seen a return to sunshine and warm temperatures at higher elevations. This weather has mainly caused snowpack consolidation and stabilizing and smaller wet loose snow avalanches.

The warm days and cooler nights lately should have been producing generally stable surface crusts on most slopes in most of the area. A generally favorable mid and lower snowpack of crust layers and melt form crystals should be seen in most of the area. Spring conditions and melt freeze snow through the entire snowpack has been reported on some solar aspects. The avalanche danger is low at lower elevations where there is little snow and and ample terrain and vegetation anchors.

Colder more winter like layers are locally surviving on some shaded north or lee slopes and this is where small areas of surviving slab layers should be most likely. NWAC observers at Hurricane and at Nason Ridge the past couple days are reporting moderate or hard sudden collapse and sudden planar results in snow pit tests in the upper snow pack due to crusts and thin faceted snow layers. Such layers would likely require larger triggers such as a falling cornice or a snow mobile.

ECTP29 SC Q1 at 67 cm due to crust and facet layers at Nason Ridge, NWAC observer Tom Curtis, 20 January.

Faceted crystals from the upper snow pack, Klahhane Ridge near Hurricane Ridge, NWAC observer Katy Reid, 20 January.

Quite a difference on north and south slopes in the vicinity of Hurricane Ridge,NWAC observer Katy Reid, 20 January.

Cornice/avalanche fatality on Lewis Peak: A climber apparently walked onto a cornice on the summit of Lewis Peak east of Everett about Noon on Saturday, 18 January and was killed in the resulting cornice fall and triggered avalanche. A report will be available soon on the NWAC web site. Try to assess as best possible the likelihood of cornices and that you are over solid ground before venturing onto snow covered summits and ridges.

Local non-avalanche hazard Snoqualmie Pass area:  On 13 January a heavy local freezing rain event occurred in the Snoqualmie Pass area above about 4500 feet, covering the surface with about a 2-3 inch ice crust.  This crust should break down over time but a fall on a slope on this surface could result in a long and dangerous ride!