Lawinenlagebericht

West Slopes Central

Northwest Avalanche Center
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Lawinengefahr

Thu
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
1 · Gering
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Kernpunkte

A small avalanche or finding a thinner spot in the snowpack could re-awaken larger persistent slab avalanches.  Tread carefully in and around higher consequence terrain, especially on the northern half of the compass.  You may see small loose avalanches release on steep slopes below rocky features as the sun rises and temperatures moderate. 

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Unlikely
    Größe
    2–2.5

    Other than a few photographs of a collection of large crowns on the north side of Mt Pilchuck, we know very little about the current state of this problem in the West Central zone. Here’s what we do know: 

    • Weak snow grains (facets) sometimes paired with a thin crust, were documented prior to the last storm. 
    • This snowpack structure is incredibly similar to other NWAC forecast zones. 
    • These weak layers should be most common on shaded aspects. 
    • There is no easy way to assess a slope’s stability. 
    • The further away from the last storm cycle we get, the less likely an avalanche may be, but the consequences are the same. 

    You’re most likely to trigger an avalanche in areas where the snowpack is thinner such as near rocks, along convexities, or on unsupported supported slopes.  You may need a large trigger; groups of people, cliff drops, or small wind slab avalanche to unlock deeper instabilities.  Stack the odds in your favor by avoiding complex, higher-consequence terrain.

    (2/9/2025)

    This slew of natural avalanches in the West Fork of Swift Creek/West North were reported on Sunday. The time of occurrence and weak layer are hard to pin down. Whatever the details, it's proof the layering is still out there to produce slab avalanches. North aspect at 5500'.

    Photo: Andrew Richardson

Avalanche Discussion

This zone has likely seen less wind than areas further north, but without good data at upper elevations, we don't know the extent of recent wind-transported snow from N-NE higher elevation winds. Watch out for textured surfaces or wind lips that point toward firm pillow-like slabs. Triggering a wind slab avalanche would have consequences on its own, but you definitely don't want a smaller wind slab avalanche to step down and trigger a larger and less survivable persistent slab avalanche.  Tread carefully around big open slopes. 

After a cold start, Wednesday will offer some temperature moderation with afternoon mid-mountain high temperatures in the mid to upper 20s.  While not listed as an avalanche problem, ample sunshine and warmer temperatures may kick off a round of small loose avalanches on very steep sunny slopes, especially near and below exposed rock features.  Whether these small loose avalanches are of the dry or wet variety isn't all that important, just make sure you don't get surprised by one near a terrain trap at any elevation.    

Below the recent snow, two potential weak layers exist. Weak sugary faces often with a thin crust formed during the long January Drought (JDL). Just below, you will also find facets above and below a slightly thicker crust from 1/10. Warm sunny weather generally destroyed these layers on southerly aspects and instead left one stout crust buried on 1/30. Uncertainty around these layers continues to keep travelers on their toes.

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