Avalanche forecast

West Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
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Out of date — this forecast expired 4 years ago.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

A natural avalanche cycle Monday led to mainly human-triggered avalanches Tuesday. Likelihood of triggering an avalanche will continue to slowly decrease, but it is still likely that you can trigger a large avalanche on steep, unsupported slopes Wednesday. Steer around slopes steeper than 35 degrees until one more day has passed since this large, warm precipitation event.

Avalanche problems

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    Mid and lower elevation were saturated over a foot deep with water on Tuesday. There were reports of easily triggered wet loose avalanches in near treeline areas, and also signs of wet slab avalanches. We’re uncertain how reactive they will remain on Wednesday, but keep them in mind for another day. 

    As the water drains, keep tabs on how wet the snow that you’re traveling on is. Pay attention to how easy it is to trigger wet loose avalanches from the top of steep slopes, or if any are still running naturally. It is harder to determine whether you might trigger a wet slab avalanche, but you’d be most likely to trigger one on a large, unsupported slope, a location to consider steering around in areas greater than 35 degrees on Wednesday.

    (3/1/2022) Several wet slab avalanche crowns are visible in this photo from about 4400ft on a NE aspect in the Baker backcountry. Photo: Lee Lazzara

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    In above treeline areas thick slabs of drier snow are present. The storm brought over 3 feet of snow to the upper elevations, and it settled into very dense slabs. Avalanches were reported in wind loaded and non-wind loaded areas, mainly because of the sheer quantity of new snow (weight) we received and its upside-down nature. 

    Limited information is known about above treeline areas at this time, but if you plan to head out on Wednesday, consider letting the snowpack adjust for one more day, and same as above, avoid steep slopes. Don’t ignore obvious signs of instability like shooting cracks, whumphs, or recent avalanche activity.  Approach any steep slope with caution and remain aware of terrain above you.

    (3/1/2022)

    A widely propagating crown, typical of the unusual avalanche conditions which were present in the last few days. This avalanche may have had a mix of moist snow on top and dry snow beneath, Typical of this strange avalanche cycle. E, 5000ft in the Baker backcountry.

    Photo: Lee Lazzara

Avalanche Discussion

Uncertainty exists as to how long the snowpack instabilities will remain a concern for. Likelihood may trend more towards Possible for both avalanche problems on Wednesday, but information is limited at this time. With such large amounts of water and the cooling trend not taking place as much until Wednesday night, consider taking it easy in the backcountry for one more day. 

The Heather Meadows weather station at Mt Baker received 9 inches of water since Saturday evening. Most of it came in as moist snow at that elevation, until Monday night when rain began saturating the snowpack. Precipitation didn’t let up Monday night, and instead snowlines rose as over an inch of rain fell. A natural avalanche cycle with large and very large avalanches happened during the day Monday, and probably overnight as well while rain absorbed into the snowpack at higher elevations than before. Wet loose and slab avalanches were reported in areas that don’t typically run, with crowns seen in unusual places. Activity remained elevated Tuesday as precipitation only slightly let up. Visibility remained poor on Tuesday, but several large debris piles and crowns of at least 3 feet were seen in a limited area. A weak old snow surface might be to blame for avalanches running as deep as the old snow interface. We expect to see many more large and unusual avalanches once visibility improves.

Regions covered