Avalanche forecast

West Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

It takes multiple days for 8" of water to drain the snowpack, leaving us with a lingering threat for very large glide avalanches. Identify and reduce exposure to steep bedrock slopes and large "brown frown" open cracks. At upper elevations, you can trigger slabs on steep wind-loaded slopes, particularly under fresh, sharp cornices.

Avalanche problems

  • Glide Cracks

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3

    Although much of the wet avalanche activity remains behind us, it takes time for water to fully drain an 80+" snowpack. Deep rain rills serve as a reminder that the lower and mid-elevation snowpacks formed a drainage network to let massive amounts of water drain. Glide avalanches tend to linger the longest after a massive rain event (ending early Saturday) as water continues to lubricate bedrock faces. A glide avalanche frequently takes the entire season's snowpack along with it, making them nearly unsurvivable if you are in the wrong spot and a surficial crust doesn't prevent the problem. The glide threat is becoming low probability, but remains high consequence. We don't know when a particularly slope will avalanche, but our terrain selection can help us avoid the problem. Don't linger under smooth bed surfaces (which can be identified by satellite imagery) and/or "brown frowns of glide cracks."  

     

    Glide cracks were spotted on a number of slopes on 1/14 in the nearby West Central Zone. Give these areas a wide berth by not traveling on or beneath them.

    Photo: Irene Henninger

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

     Significant new snow fell above 5000-5500' through Friday night, with some wind tranport likely maintaining instability on specific terrain features at upper elevations. Use fresh, sharp cornices to provide visual clues to navigate around the problem. Firm, punchy snow layers or thicker deposits overlying the crust can also help you identify wind-loaded areas. Steer around potentially wind-loaded start zones steeper than 35 degrees.

    Example: Wind slab triggered on a wind loaded slope just below ridgeline.

    Photo: Sarah Ehm

Avalanche Discussion

The weather improved in the North Cascades as a deluge finally shut off early Saturday.   About 8" of water was recorded at the Mt Baker station since early Thursday morning and the rain line likely rose to at least 6500' during the peak of the storm, perhaps higher.  Photos from Bagley Lakes show a cycle of large wet loose avalanches that ran on many steep slopes during the storm. Smaller wet loose avalanches could be found as the sun impacted fresh snow.

NWAC professionals found water draining the snowpack and improving stability in the nearby West Central zone. Glide cracks were present and open. They did not find any unexpected or concerning avalanches. 

Regions covered