Avalanche Forecast

A cooling trend continues with scattered light showers overnight Tuesday and early Wednesday with light to moderate winds.

The 4-8 inches of recent snow since Sunday will be available for wind transport and will support wind slabs forming near and above treeline on a variety of exposed slopes.

The next strong storm is forecast to arrive Wednesday night, however if the storm arrives earlier than forecast expect increasing danger late Wednesday. Watch for changing weather conditions through the day Wednesday and be prepared to alter plans accordingly.  

Early season hazards still exist. Many creek beds have still not filled in for the winter and multiple crust surfaces may may travel at lower elevations more difficult than anticipated.

Since Sunday most east slope areas have received 4-8 inches of snow.

In the northeast Cascades, very light amounts of new snowfall have been noted at Snotels since late last week.  No freezing rain crust exists in ski terrain along the Hwy 20 corridor nor has buried SH been discovered in avalanche terrain.

Extensive freezing rain accumulated at mid and lower elevations along the central-east slopes of the Cascades as well as in the Stevens and Snoqualmie Pass areas Thursday night and Friday. This significant freezing rain event has likely destroyed or capped a variety of existing snow surface forms. The newly formed crust is limiting the current avalanche potential and formed over a relatively strong older snowpack. 

Older wind slabs have been trending toward unreactive in the Washington Pass area, but with limited field observations and areas of new wind slabs noted on the Cascade West slopes, we are leaving wind slabs in the forecast, mainly for shallow fresh wind slabs.

Snowdepth decreases substantially the further east of the Cascade crest one travels. In many areas below treeline, there is not enough snow to present an avalanche danger. 

Observations

North

On Monday, NCMG found  4-6 inches (10-15 cm) of lower density snowfall over a well consolidated base with little signs of recent wind transport in the Washington Pass area. No new avalanches have been observed in this area over the last two days. The 1/5 freezing rain crust found further south has not been found along the Hwy 20 corridor. 

Central

A public observation from Friday 1/5 in the Mission Ridge backcountry noted a 1/4" thick freezing rain crust up to 5000' making for treacherous travel conditions. 

Basal facets (2-3mm) observed on 1/2 above 5000' on NW-N-E aspects and failing in snowpit tests in the Blewett Pass area (and likely the Mission Ridge area) will need to be watched when enough snow returns to this area to create a potential avalanche problem.  

South

No recent observations