Avalanche forecast

Stevens Pass

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

A slight bump in easterly winds may drift some more snow on Monday. Identify large, steep terrain features that may hold stiffer or cohesive slabs to steer around. With strong sun and slightly warming temperatures, slopes in the direct sun may become more reactive.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2.5

    Another bump in Easterly winds may drift low density cold snow into shallow slabs. Easterlies blew strong through the pass on Saturday. At least a few recent wind slabs were observed, one human triggered from exposed slopes in the clear cuts near Henry Creek, and another higher up on the west face of Rock. Identify large, open, and steep slopes where cohesive drifts of snow may exist. Slabs may be easier to trigger on slopes receiving direct sun, and any areas with fresh drifting. Look for surface textures and feel for stiffer snow as you travel to get an idea of steeper areas you may want to steer around.

    If you receive any "red flag" signs of instability like whumpfing collapses or recent large avalanches, stick to lower-angle and supported terrain. The 4-6ft of recent storm snow is resting on crusts and weaker snow buried in late December, and a few deeper and larger avalanches have occurred around the 11th. While triggering one of these monsters is unlikely, some potential still exists for the time being. A smaller slab could potentiall step down to these deeper layers in larger terrain features. 

    (1/14/2024)

    A small windslab  likely released on 1/13 with strong easterly winds. 

    Photo: Matt Primomo

Avalanche Discussion

Martin Luther King Jr day should be another beautiful day in the mountains. Snow surfaces are still very nice cold powder in many sheltered areas. You may find varying degrees of wind stiffened snow on higher exposed slopes. With slightly warming temperatures, the sun may start to affect snow surfaces on steep south facing slopes just a little bit on Monday. 

On Sunday, we toured near Smithbrook, finding fresh and overhung cornices on northeast aspects. The snow surfaces on south facing slopes were just ever so slightly affected by the sun later in the day. Small facets likely formed above the new thin suncrust, called radiation recrystallization. An interesting 'step down' avalanche was observed on the NE side of Jove Peak (see photo below). This may have been from the heavy snowfall event and strong winds on the 11th. Another larger avalanche was estimated to have run on the 11th off the S side of Rock Mountain in the Camp Chutes. It stopped low in the track. On Saturday, a number of folks in the clear cut zone of Henry Creek found lots of wind affected snow surfaces from the active east winds. Above 4,500ft observers reported much less wind, and less wind affeced snow, so the easterlies may have been confined to lower elevations in some areas. On open, exposed areas to the wind, you might find stiff wind board-like snow surfaces mixed in with softer areas. 

Between the 6th and 11th the zone picked up around 5 feet of snow, with strong to extreme winds at times. Many avalanches that occurred have become difficult to observe as they're sifted over by wind drifting, or buried by more recent snow. 3 larger avalanches have stood out; The very large step down slide on the NE side of Jove (est 1/11), A large avalanche on the S side of Rock Mountain west of Berne (est 1/11), and an explosive triggered slab 6ft deep in a heavily wind loaded area near Gemini Pass at Stevens Pass Mtn Resort on the 10th. The layer responsible for these larger slides is likely the Solstice crust, which is now about 4 feet below the surface in much of the zone. Snow profiles have shown these weak layers to consist of faceted melt forms, and some snowpack tests have given sudden and propagating results. Although these deeper weak layers appear to be dormant for the time being, they're worth considering in your terrain selection. They could become active again with a large enough load.

Further east there is a similar but shallower snowpack structure. Here, persistent slabs are trending less likely, but remain on the menu. 

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